Michelle Mourad, MD

Targeting “discharge before noon” (DBN) for hospitalized patients has been proposed as a way to improve hospital throughput and patient safety by reducing emergency department (ED) boarding and crowding. In this issue, Kirubarajan et al¹ report no association between morning discharge and length of stay (LOS) for either the ED or hospitalization.¹ This large (189,781 patients) 7-year study from seven quite different Canadian hospitals adds important data to a literature that remains divided about whether DBN helps or hurts hospital LOS and ED boarding.

Unlike trials reporting interventions to encourage DBN, this observational study was unique in that it took each day as the unit of observation. This method cleverly allowed the authors to examine whether days with more discharges before noon conferred a lower mean ED and inpatient LOS among patients admitted on those days. Their approach appropriately reframes the central issue as one of patient flow.

Kirubarajan et al’s most notable, and perhaps surprising, finding is the lack of association between morning discharge and ED LOS. Computer modeling supports the hypothesis that ED throughput will improve on days with earlier inpatient bed availability.² Several studies have also noted earlier ED departure times and decreased ED wait times after implementing interventions to promote DBN.³ Why might the authors’ findings contradict previous studies? Their outcomes may in part be due to high ED LOS (>14 hours), exceeding Canadian published targets and reports from the United States.^4,5 Problems relating to ED resources, practice, and hospital census may have overwhelmed DBN as factors in boarding. The interpretation of their findings is limited by the authors’ decision to report only ED LOS, rather than including the time between a decision to admit and ED departure (boarding time).

While early studies that focused on interventions to promote DBN noted decreased inpatient LOS after their implementation, later studies found no effect or even an increase in LOS for general internal medicine patients. Concerns have been raised about the confounding effect of concurrent initiatives aimed at improving LOS as well as misaligned incentives to delay discharge to the following morning. As the number of conflicting studies mounts, and with the current report in hand, it is tempting to conclude that for the DBN evidence base as a whole, we are observing random variation around no effect.

With growing doubt about benefits of morning discharge, perhaps we should turn our attention away from the question of how to increase DBN and consider instead why and at what cost. Hospitals are delicate organisms; a singular focus on one metric will undoubtedly impact others. Does the effort to discharge before noon consume valuable morning hours and detract from the care of other patients? Are patients held overnight unnecessarily to comply with DBN? Are there consequences in patient, nursing, or trainee satisfaction? Is bedside teaching affected?

And as concepts of patient-centered care are increasingly valued, we may ask whether DBN is such a concept, or is it rather an increasingly dubious strategy aimed at regularizing hospital operations? The need for a more holistic assessment of “discharge quality” is apparent. Instead of focusing on a particular hour, initiatives should determine the “best, earliest discharge time” for each patient and align multidisciplinary efforts toward this patient-centered goal. Such efforts are already underway in pediatric hospitals, where fixed discharge times are being replaced by discharge milestones embedded into the electronic medical record.⁶ An instrument to track “discharge readiness” such as this one, paired with ongoing analysis of the barriers to timely discharge, might better facilitate throughput by targeting the entire admission, rather than concentrating pressure on its final hours.

Targeting “discharge before noon” (DBN) for hospitalized patients has been proposed as a way to improve hospital throughput and patient safety by reducing emergency department (ED) boarding and crowding. In this issue, Kirubarajan et al¹ report no association between morning discharge and length of stay (LOS) for either the ED or hospitalization.¹ This large (189,781 patients) 7-year study from seven quite different Canadian hospitals adds important data to a literature that remains divided about whether DBN helps or hurts hospital LOS and ED boarding.

Unlike trials reporting interventions to encourage DBN, this observational study was unique in that it took each day as the unit of observation. This method cleverly allowed the authors to examine whether days with more discharges before noon conferred a lower mean ED and inpatient LOS among patients admitted on those days. Their approach appropriately reframes the central issue as one of patient flow.

Kirubarajan et al’s most notable, and perhaps surprising, finding is the lack of association between morning discharge and ED LOS. Computer modeling supports the hypothesis that ED throughput will improve on days with earlier inpatient bed availability.² Several studies have also noted earlier ED departure times and decreased ED wait times after implementing interventions to promote DBN.³ Why might the authors’ findings contradict previous studies? Their outcomes may in part be due to high ED LOS (>14 hours), exceeding Canadian published targets and reports from the United States.^4,5 Problems relating to ED resources, practice, and hospital census may have overwhelmed DBN as factors in boarding. The interpretation of their findings is limited by the authors’ decision to report only ED LOS, rather than including the time between a decision to admit and ED departure (boarding time).

While early studies that focused on interventions to promote DBN noted decreased inpatient LOS after their implementation, later studies found no effect or even an increase in LOS for general internal medicine patients. Concerns have been raised about the confounding effect of concurrent initiatives aimed at improving LOS as well as misaligned incentives to delay discharge to the following morning. As the number of conflicting studies mounts, and with the current report in hand, it is tempting to conclude that for the DBN evidence base as a whole, we are observing random variation around no effect.

With growing doubt about benefits of morning discharge, perhaps we should turn our attention away from the question of how to increase DBN and consider instead why and at what cost. Hospitals are delicate organisms; a singular focus on one metric will undoubtedly impact others. Does the effort to discharge before noon consume valuable morning hours and detract from the care of other patients? Are patients held overnight unnecessarily to comply with DBN? Are there consequences in patient, nursing, or trainee satisfaction? Is bedside teaching affected?

And as concepts of patient-centered care are increasingly valued, we may ask whether DBN is such a concept, or is it rather an increasingly dubious strategy aimed at regularizing hospital operations? The need for a more holistic assessment of “discharge quality” is apparent. Instead of focusing on a particular hour, initiatives should determine the “best, earliest discharge time” for each patient and align multidisciplinary efforts toward this patient-centered goal. Such efforts are already underway in pediatric hospitals, where fixed discharge times are being replaced by discharge milestones embedded into the electronic medical record.⁶ An instrument to track “discharge readiness” such as this one, paired with ongoing analysis of the barriers to timely discharge, might better facilitate throughput by targeting the entire admission, rather than concentrating pressure on its final hours.

Targeting “discharge before noon” (DBN) for hospitalized patients has been proposed as a way to improve hospital throughput and patient safety by reducing emergency department (ED) boarding and crowding. In this issue, Kirubarajan et al¹ report no association between morning discharge and length of stay (LOS) for either the ED or hospitalization.¹ This large (189,781 patients) 7-year study from seven quite different Canadian hospitals adds important data to a literature that remains divided about whether DBN helps or hurts hospital LOS and ED boarding.

Unlike trials reporting interventions to encourage DBN, this observational study was unique in that it took each day as the unit of observation. This method cleverly allowed the authors to examine whether days with more discharges before noon conferred a lower mean ED and inpatient LOS among patients admitted on those days. Their approach appropriately reframes the central issue as one of patient flow.

Kirubarajan et al’s most notable, and perhaps surprising, finding is the lack of association between morning discharge and ED LOS. Computer modeling supports the hypothesis that ED throughput will improve on days with earlier inpatient bed availability.² Several studies have also noted earlier ED departure times and decreased ED wait times after implementing interventions to promote DBN.³ Why might the authors’ findings contradict previous studies? Their outcomes may in part be due to high ED LOS (>14 hours), exceeding Canadian published targets and reports from the United States.^4,5 Problems relating to ED resources, practice, and hospital census may have overwhelmed DBN as factors in boarding. The interpretation of their findings is limited by the authors’ decision to report only ED LOS, rather than including the time between a decision to admit and ED departure (boarding time).

While early studies that focused on interventions to promote DBN noted decreased inpatient LOS after their implementation, later studies found no effect or even an increase in LOS for general internal medicine patients. Concerns have been raised about the confounding effect of concurrent initiatives aimed at improving LOS as well as misaligned incentives to delay discharge to the following morning. As the number of conflicting studies mounts, and with the current report in hand, it is tempting to conclude that for the DBN evidence base as a whole, we are observing random variation around no effect.

With growing doubt about benefits of morning discharge, perhaps we should turn our attention away from the question of how to increase DBN and consider instead why and at what cost. Hospitals are delicate organisms; a singular focus on one metric will undoubtedly impact others. Does the effort to discharge before noon consume valuable morning hours and detract from the care of other patients? Are patients held overnight unnecessarily to comply with DBN? Are there consequences in patient, nursing, or trainee satisfaction? Is bedside teaching affected?

And as concepts of patient-centered care are increasingly valued, we may ask whether DBN is such a concept, or is it rather an increasingly dubious strategy aimed at regularizing hospital operations? The need for a more holistic assessment of “discharge quality” is apparent. Instead of focusing on a particular hour, initiatives should determine the “best, earliest discharge time” for each patient and align multidisciplinary efforts toward this patient-centered goal. Such efforts are already underway in pediatric hospitals, where fixed discharge times are being replaced by discharge milestones embedded into the electronic medical record.⁶ An instrument to track “discharge readiness” such as this one, paired with ongoing analysis of the barriers to timely discharge, might better facilitate throughput by targeting the entire admission, rather than concentrating pressure on its final hours.

The discharge process is a critical bottleneck for efficient patient flow through the hospital. Delayed discharges translate into delays in admissions and other patient transitions, often leading to excess costs, patient dissatisfaction, and even patient harm.^1-3 The emergency department is particularly impacted by these delays; bottlenecks there lead to overcrowding, increased overall hospital length of stay, and increased risks for bad outcomes during hospitalization.²

Academic medical centers in particular may struggle with delayed discharges. In a typical teaching hospital, a team composed of an attending physician and housestaff share responsibility for determining the discharge plan. Additionally, clinical teaching activities may affect the process and quality of discharge.^4-6

The prevalence and causes of delayed discharges vary greatly.^7-9 To improve efficiency around discharge, many hospitals have launched initiatives designed to discharge patients earlier in the day, including goal setting (“discharge by noon”), scheduling discharge appointments, and using quality-improvement methods, such as Lean Methodology (LEAN), to remove inefficiencies within discharge processes.^10-12 However, there are few data on the prevalence and effectiveness of different strategies.

The aim of this study was to survey academic hospitalist and general internal medicine physician leaders to elicit their perspectives on the factors contributing to discharge timing and the relative importance and effectiveness of early-discharge initiatives.

Study Design, Participants, and Oversight

We obtained a list of 115 university-affiliated hospitals associated with a residency program and, in most cases, a medical school from Vizient Inc. (formerly University HealthSystem Consortium), an alliance of academic medical centers and affiliated hospitals. Each member institution submits clinical data to allow for the benchmarking of outcomes to drive transparency and quality improvement.¹³ More than 95% of the nation’s academic medical centers and affiliated hospitals participate in this collaborative. Vizient works with members but does not set nor promote quality metrics, such as discharge timeliness. E-mail addresses for hospital medicine physician leaders (eg, division chief) of major academic medical centers were obtained from each institution via publicly available data (eg, the institution’s website). When an institution did not have a hospital medicine section, we identified the division chief of general internal medicine. The University of California, San Francisco Institutional Review Board approved this study.

Survey Development and Domains

We developed a 30-item survey to evaluate 5 main domains of interest: current discharge practices, degree of prioritization of early discharge on the inpatient service, barriers to timely discharge, prevalence and perceived effectiveness of implemented early-discharge initiatives, and barriers to implementation of early-discharge initiatives.

Respondents were first asked to identify their institutions’ goals for discharge time. They were then asked to compare the priority of early-discharge initiatives to other departmental quality-improvement initiatives, such as reducing 30-day readmissions, improving interpreter use, and improving patient satisfaction. Next, respondents were asked to estimate the degree to which clinical or patient factors contributed to delays in discharge. Respondents were then asked whether specific early-discharge initiatives, such as changes to rounding practices or communication interventions, were implemented at their institutions and, if so, the perceived effectiveness of these initiatives at meeting discharge targets. We piloted the questions locally with physicians and researchers prior to finalizing the survey.

Data Collection

We sent surveys via an online platform (Research Electronic Data Capture).¹⁴ Nonresponders were sent 2 e-mail reminders and then a follow-up telephone call asking them to complete the survey. Only 1 survey per academic medical center was collected. Any respondent who completed the survey within 2 weeks of receiving it was entered to win a Kindle Fire.

Data Analysis

We summarized survey responses using descriptive statistics. Analysis was completed in IBM SPSS version 22 (Armonk, NY).

Survey Respondent and Institutional Characteristics

Of the 115 institutions surveyed, we received 61 responses (response rate of 53%), with 39 (64%) respondents from divisions of hospital medicine and 22 (36%) from divisions of general internal medicine. A majority (n = 53; 87%) stated their medicine services have a combination of teaching (with residents) and nonteaching (without residents) teams. Thirty-nine (64%) reported having daily multidisciplinary rounds.

Early Discharge as a Priority

Forty-seven (77%) institutional representatives strongly agreed or agreed that early discharge was a priority, with discharge by noon being the most common target time (n = 23; 38%). Thirty (50%) respondents rated early discharge as more important than improving interpreter use for non-English-speaking patients and equally important as reducing 30-day readmissions (n = 29; 48%) and improving patient satisfaction (n = 27; 44%).

Factors Delaying Discharge

The most common factors perceived as delaying discharge were considered external to the hospital, such as postacute care bed availability or scheduled (eg, ambulance) transport delays (n = 48; 79%), followed by patient factors such as patient transport issues (n = 44; 72%). Less commonly reported were workflow issues, such as competing primary team priorities or case manager bandwidth (n = 38; 62%; Table 1).

Initiatives to Improve Discharge

The most commonly implemented initiatives perceived as effective at improving discharge times were the preemptive identification of early discharges to plan discharge paperwork (n = 34; 56%), communication with patients about anticipated discharge time on the day prior to discharge (n = 29; 48%), and the implementation of additional rounds between physician teams and case managers specifically around discharge planning (n = 28; 46%). Initiatives not commonly implemented included regular audit of and feedback on discharge times to providers and teams (n = 21; 34%), the use of a discharge readiness checklist (n = 26; 43%), incentives such as bonuses or penalties (n = 37; 61%), the use of a whiteboard to indicate discharge times (n = 23; 38%), and dedicated quality-improvement approaches such as LEAN (n = 37; 61%; Table 2).

Our study suggests early discharge for medicine patients is a priority among academic institutions. Hospitalist and general internal medicine physician leaders in our study generally attributed delayed discharges to external factors, particularly unavailability of postacute care facilities and transportation delays. Having issues with finding postacute care placements is consistent with previous findings by Selker et al.¹⁵ and Carey et al.⁸ This is despite the 20-year difference between Selker et al.’s study and the current study, reflecting a continued opportunity for improvement, including stronger partnerships with local and regional postacute care facilities to expedite care transition and stronger discharge-planning efforts early in the admission process. Efforts in postacute care placement may be particularly important for Medicaid-insured and uninsured patients.

Our responders, hospitalist and internal medicine physician leaders, did not perceive the additional responsibilities of teaching and supervising trainees to be factors that significantly delayed patient discharge. This is in contrast to previous studies, which attributed delays in discharge to prolonged clinical decision-making related to teaching and supervision.^4-6,8 This discrepancy may be due to the fact that we only surveyed single physician leaders at each institution and not residents. Our finding warrants further investigation to understand the degree to which resident skills may impact discharge planning and processes.

Institutions represented in our study have attempted a variety of initiatives promoting earlier discharge, with varying levels of perceived success. Initiatives perceived to be the most effective by hospital leaders centered on 2 main areas: (1) changing individual provider practice and (2) anticipatory discharge preparation. Interestingly, this is in discordance with the main factors labeled as causing delays in discharges, such as obtaining postacute care beds, busy case managers, and competing demands on primary teams. We hypothesize this may be because such changes require organization- or system-level changes and are perceived as more arduous than changes at the individual level. In addition, changes to individual provider behavior may be more cost- and time-effective than more systemic initiatives.

Our findings are consistent with the work published by Wertheimer and colleagues,¹¹ who show that additional afternoon interdisciplinary rounds can help identify patients who may be discharged before noon the next day. In their study, identifying such patients in advance improved the overall early-discharge rate the following day.

Our findings should be interpreted in light of several limitations. Our survey only considers the perspectives of hospitalist and general internal medicine physician leaders at academic medical centers that are part of the Vizient Inc. collaborative. They do not represent all academic or community-based medical centers. Although the perceived effectiveness of some initiatives was high, we did not collect empirical data to support these claims or to determine which initiative had the greatest relative impact on discharge timeliness. Lastly, we did not obtain resident, nursing, or case manager perspectives on discharge practices. Given their roles as frontline providers, we may have missed these alternative perspectives.

Our study shows there is a strong interest in increasing early discharges in an effort to improve hospital throughput and patient flow.

Acknowledgments

The authors thank all participants who completed the survey and Danielle Carrier at Vizient Inc. (formally University HealthSystem Consortium) for her assistance in obtaining data.

Disclosures

Hemali Patel, Margaret Fang, Michelle Mourad, Adrienne Green, Ryan Murphy, and James Harrison report no conflicts of interest. At the time the research was conducted, Robert Wachter reported that he is a member of the Lucian Leape Institute at the National Patient Safety Foundation (no compensation except travel expenses); recently chaired an advisory board to England’s National Health Service (NHS) reviewing the NHS’s digital health strategy (no compensation except travel expenses); has a contract with UCSF from the Agency for Healthcare Research and Quality to edit a patient-safety website; receives compensation from John Wiley & Sons for writing a blog; receives royalties from Lippincott Williams & Wilkins and McGraw-Hill Education for writing and/or editing several books; receives stock options for serving on the board of Acuity Medical Management Systems; receives a yearly stipend for serving on the board of The Doctors Company; serves on the scientific advisory boards for amino.com, PatientSafe Solutions Inc., Twine, and EarlySense (for which he receives stock options); has a small royalty stake in CareWeb, a hospital communication tool developed at UCSF; and holds the Marc and Lynne Benioff Endowed Chair in Hospital Medicine and the Holly Smith Distinguished Professorship in Science and Medicine at UCSF.

The discharge process is a critical bottleneck for efficient patient flow through the hospital. Delayed discharges translate into delays in admissions and other patient transitions, often leading to excess costs, patient dissatisfaction, and even patient harm.^1-3 The emergency department is particularly impacted by these delays; bottlenecks there lead to overcrowding, increased overall hospital length of stay, and increased risks for bad outcomes during hospitalization.²

Academic medical centers in particular may struggle with delayed discharges. In a typical teaching hospital, a team composed of an attending physician and housestaff share responsibility for determining the discharge plan. Additionally, clinical teaching activities may affect the process and quality of discharge.^4-6

The prevalence and causes of delayed discharges vary greatly.^7-9 To improve efficiency around discharge, many hospitals have launched initiatives designed to discharge patients earlier in the day, including goal setting (“discharge by noon”), scheduling discharge appointments, and using quality-improvement methods, such as Lean Methodology (LEAN), to remove inefficiencies within discharge processes.^10-12 However, there are few data on the prevalence and effectiveness of different strategies.

The aim of this study was to survey academic hospitalist and general internal medicine physician leaders to elicit their perspectives on the factors contributing to discharge timing and the relative importance and effectiveness of early-discharge initiatives.

Study Design, Participants, and Oversight

We obtained a list of 115 university-affiliated hospitals associated with a residency program and, in most cases, a medical school from Vizient Inc. (formerly University HealthSystem Consortium), an alliance of academic medical centers and affiliated hospitals. Each member institution submits clinical data to allow for the benchmarking of outcomes to drive transparency and quality improvement.¹³ More than 95% of the nation’s academic medical centers and affiliated hospitals participate in this collaborative. Vizient works with members but does not set nor promote quality metrics, such as discharge timeliness. E-mail addresses for hospital medicine physician leaders (eg, division chief) of major academic medical centers were obtained from each institution via publicly available data (eg, the institution’s website). When an institution did not have a hospital medicine section, we identified the division chief of general internal medicine. The University of California, San Francisco Institutional Review Board approved this study.

Survey Development and Domains

We developed a 30-item survey to evaluate 5 main domains of interest: current discharge practices, degree of prioritization of early discharge on the inpatient service, barriers to timely discharge, prevalence and perceived effectiveness of implemented early-discharge initiatives, and barriers to implementation of early-discharge initiatives.

Respondents were first asked to identify their institutions’ goals for discharge time. They were then asked to compare the priority of early-discharge initiatives to other departmental quality-improvement initiatives, such as reducing 30-day readmissions, improving interpreter use, and improving patient satisfaction. Next, respondents were asked to estimate the degree to which clinical or patient factors contributed to delays in discharge. Respondents were then asked whether specific early-discharge initiatives, such as changes to rounding practices or communication interventions, were implemented at their institutions and, if so, the perceived effectiveness of these initiatives at meeting discharge targets. We piloted the questions locally with physicians and researchers prior to finalizing the survey.

Data Collection

We sent surveys via an online platform (Research Electronic Data Capture).¹⁴ Nonresponders were sent 2 e-mail reminders and then a follow-up telephone call asking them to complete the survey. Only 1 survey per academic medical center was collected. Any respondent who completed the survey within 2 weeks of receiving it was entered to win a Kindle Fire.

Data Analysis

We summarized survey responses using descriptive statistics. Analysis was completed in IBM SPSS version 22 (Armonk, NY).

Survey Respondent and Institutional Characteristics

Of the 115 institutions surveyed, we received 61 responses (response rate of 53%), with 39 (64%) respondents from divisions of hospital medicine and 22 (36%) from divisions of general internal medicine. A majority (n = 53; 87%) stated their medicine services have a combination of teaching (with residents) and nonteaching (without residents) teams. Thirty-nine (64%) reported having daily multidisciplinary rounds.

Early Discharge as a Priority

Forty-seven (77%) institutional representatives strongly agreed or agreed that early discharge was a priority, with discharge by noon being the most common target time (n = 23; 38%). Thirty (50%) respondents rated early discharge as more important than improving interpreter use for non-English-speaking patients and equally important as reducing 30-day readmissions (n = 29; 48%) and improving patient satisfaction (n = 27; 44%).

Factors Delaying Discharge

The most common factors perceived as delaying discharge were considered external to the hospital, such as postacute care bed availability or scheduled (eg, ambulance) transport delays (n = 48; 79%), followed by patient factors such as patient transport issues (n = 44; 72%). Less commonly reported were workflow issues, such as competing primary team priorities or case manager bandwidth (n = 38; 62%; Table 1).

Initiatives to Improve Discharge

The most commonly implemented initiatives perceived as effective at improving discharge times were the preemptive identification of early discharges to plan discharge paperwork (n = 34; 56%), communication with patients about anticipated discharge time on the day prior to discharge (n = 29; 48%), and the implementation of additional rounds between physician teams and case managers specifically around discharge planning (n = 28; 46%). Initiatives not commonly implemented included regular audit of and feedback on discharge times to providers and teams (n = 21; 34%), the use of a discharge readiness checklist (n = 26; 43%), incentives such as bonuses or penalties (n = 37; 61%), the use of a whiteboard to indicate discharge times (n = 23; 38%), and dedicated quality-improvement approaches such as LEAN (n = 37; 61%; Table 2).

Our study suggests early discharge for medicine patients is a priority among academic institutions. Hospitalist and general internal medicine physician leaders in our study generally attributed delayed discharges to external factors, particularly unavailability of postacute care facilities and transportation delays. Having issues with finding postacute care placements is consistent with previous findings by Selker et al.¹⁵ and Carey et al.⁸ This is despite the 20-year difference between Selker et al.’s study and the current study, reflecting a continued opportunity for improvement, including stronger partnerships with local and regional postacute care facilities to expedite care transition and stronger discharge-planning efforts early in the admission process. Efforts in postacute care placement may be particularly important for Medicaid-insured and uninsured patients.

Our responders, hospitalist and internal medicine physician leaders, did not perceive the additional responsibilities of teaching and supervising trainees to be factors that significantly delayed patient discharge. This is in contrast to previous studies, which attributed delays in discharge to prolonged clinical decision-making related to teaching and supervision.^4-6,8 This discrepancy may be due to the fact that we only surveyed single physician leaders at each institution and not residents. Our finding warrants further investigation to understand the degree to which resident skills may impact discharge planning and processes.

Institutions represented in our study have attempted a variety of initiatives promoting earlier discharge, with varying levels of perceived success. Initiatives perceived to be the most effective by hospital leaders centered on 2 main areas: (1) changing individual provider practice and (2) anticipatory discharge preparation. Interestingly, this is in discordance with the main factors labeled as causing delays in discharges, such as obtaining postacute care beds, busy case managers, and competing demands on primary teams. We hypothesize this may be because such changes require organization- or system-level changes and are perceived as more arduous than changes at the individual level. In addition, changes to individual provider behavior may be more cost- and time-effective than more systemic initiatives.

Our findings are consistent with the work published by Wertheimer and colleagues,¹¹ who show that additional afternoon interdisciplinary rounds can help identify patients who may be discharged before noon the next day. In their study, identifying such patients in advance improved the overall early-discharge rate the following day.

Our findings should be interpreted in light of several limitations. Our survey only considers the perspectives of hospitalist and general internal medicine physician leaders at academic medical centers that are part of the Vizient Inc. collaborative. They do not represent all academic or community-based medical centers. Although the perceived effectiveness of some initiatives was high, we did not collect empirical data to support these claims or to determine which initiative had the greatest relative impact on discharge timeliness. Lastly, we did not obtain resident, nursing, or case manager perspectives on discharge practices. Given their roles as frontline providers, we may have missed these alternative perspectives.

Our study shows there is a strong interest in increasing early discharges in an effort to improve hospital throughput and patient flow.

Acknowledgments

The authors thank all participants who completed the survey and Danielle Carrier at Vizient Inc. (formally University HealthSystem Consortium) for her assistance in obtaining data.

Disclosures

Hemali Patel, Margaret Fang, Michelle Mourad, Adrienne Green, Ryan Murphy, and James Harrison report no conflicts of interest. At the time the research was conducted, Robert Wachter reported that he is a member of the Lucian Leape Institute at the National Patient Safety Foundation (no compensation except travel expenses); recently chaired an advisory board to England’s National Health Service (NHS) reviewing the NHS’s digital health strategy (no compensation except travel expenses); has a contract with UCSF from the Agency for Healthcare Research and Quality to edit a patient-safety website; receives compensation from John Wiley & Sons for writing a blog; receives royalties from Lippincott Williams & Wilkins and McGraw-Hill Education for writing and/or editing several books; receives stock options for serving on the board of Acuity Medical Management Systems; receives a yearly stipend for serving on the board of The Doctors Company; serves on the scientific advisory boards for amino.com, PatientSafe Solutions Inc., Twine, and EarlySense (for which he receives stock options); has a small royalty stake in CareWeb, a hospital communication tool developed at UCSF; and holds the Marc and Lynne Benioff Endowed Chair in Hospital Medicine and the Holly Smith Distinguished Professorship in Science and Medicine at UCSF.

The discharge process is a critical bottleneck for efficient patient flow through the hospital. Delayed discharges translate into delays in admissions and other patient transitions, often leading to excess costs, patient dissatisfaction, and even patient harm.^1-3 The emergency department is particularly impacted by these delays; bottlenecks there lead to overcrowding, increased overall hospital length of stay, and increased risks for bad outcomes during hospitalization.²

Academic medical centers in particular may struggle with delayed discharges. In a typical teaching hospital, a team composed of an attending physician and housestaff share responsibility for determining the discharge plan. Additionally, clinical teaching activities may affect the process and quality of discharge.^4-6

The prevalence and causes of delayed discharges vary greatly.^7-9 To improve efficiency around discharge, many hospitals have launched initiatives designed to discharge patients earlier in the day, including goal setting (“discharge by noon”), scheduling discharge appointments, and using quality-improvement methods, such as Lean Methodology (LEAN), to remove inefficiencies within discharge processes.^10-12 However, there are few data on the prevalence and effectiveness of different strategies.

The aim of this study was to survey academic hospitalist and general internal medicine physician leaders to elicit their perspectives on the factors contributing to discharge timing and the relative importance and effectiveness of early-discharge initiatives.

Study Design, Participants, and Oversight

We obtained a list of 115 university-affiliated hospitals associated with a residency program and, in most cases, a medical school from Vizient Inc. (formerly University HealthSystem Consortium), an alliance of academic medical centers and affiliated hospitals. Each member institution submits clinical data to allow for the benchmarking of outcomes to drive transparency and quality improvement.¹³ More than 95% of the nation’s academic medical centers and affiliated hospitals participate in this collaborative. Vizient works with members but does not set nor promote quality metrics, such as discharge timeliness. E-mail addresses for hospital medicine physician leaders (eg, division chief) of major academic medical centers were obtained from each institution via publicly available data (eg, the institution’s website). When an institution did not have a hospital medicine section, we identified the division chief of general internal medicine. The University of California, San Francisco Institutional Review Board approved this study.

Survey Development and Domains

We developed a 30-item survey to evaluate 5 main domains of interest: current discharge practices, degree of prioritization of early discharge on the inpatient service, barriers to timely discharge, prevalence and perceived effectiveness of implemented early-discharge initiatives, and barriers to implementation of early-discharge initiatives.

Respondents were first asked to identify their institutions’ goals for discharge time. They were then asked to compare the priority of early-discharge initiatives to other departmental quality-improvement initiatives, such as reducing 30-day readmissions, improving interpreter use, and improving patient satisfaction. Next, respondents were asked to estimate the degree to which clinical or patient factors contributed to delays in discharge. Respondents were then asked whether specific early-discharge initiatives, such as changes to rounding practices or communication interventions, were implemented at their institutions and, if so, the perceived effectiveness of these initiatives at meeting discharge targets. We piloted the questions locally with physicians and researchers prior to finalizing the survey.

Data Collection

We sent surveys via an online platform (Research Electronic Data Capture).¹⁴ Nonresponders were sent 2 e-mail reminders and then a follow-up telephone call asking them to complete the survey. Only 1 survey per academic medical center was collected. Any respondent who completed the survey within 2 weeks of receiving it was entered to win a Kindle Fire.

Data Analysis

We summarized survey responses using descriptive statistics. Analysis was completed in IBM SPSS version 22 (Armonk, NY).

Survey Respondent and Institutional Characteristics

Of the 115 institutions surveyed, we received 61 responses (response rate of 53%), with 39 (64%) respondents from divisions of hospital medicine and 22 (36%) from divisions of general internal medicine. A majority (n = 53; 87%) stated their medicine services have a combination of teaching (with residents) and nonteaching (without residents) teams. Thirty-nine (64%) reported having daily multidisciplinary rounds.

Early Discharge as a Priority

Forty-seven (77%) institutional representatives strongly agreed or agreed that early discharge was a priority, with discharge by noon being the most common target time (n = 23; 38%). Thirty (50%) respondents rated early discharge as more important than improving interpreter use for non-English-speaking patients and equally important as reducing 30-day readmissions (n = 29; 48%) and improving patient satisfaction (n = 27; 44%).

Factors Delaying Discharge

The most common factors perceived as delaying discharge were considered external to the hospital, such as postacute care bed availability or scheduled (eg, ambulance) transport delays (n = 48; 79%), followed by patient factors such as patient transport issues (n = 44; 72%). Less commonly reported were workflow issues, such as competing primary team priorities or case manager bandwidth (n = 38; 62%; Table 1).

Initiatives to Improve Discharge

The most commonly implemented initiatives perceived as effective at improving discharge times were the preemptive identification of early discharges to plan discharge paperwork (n = 34; 56%), communication with patients about anticipated discharge time on the day prior to discharge (n = 29; 48%), and the implementation of additional rounds between physician teams and case managers specifically around discharge planning (n = 28; 46%). Initiatives not commonly implemented included regular audit of and feedback on discharge times to providers and teams (n = 21; 34%), the use of a discharge readiness checklist (n = 26; 43%), incentives such as bonuses or penalties (n = 37; 61%), the use of a whiteboard to indicate discharge times (n = 23; 38%), and dedicated quality-improvement approaches such as LEAN (n = 37; 61%; Table 2).

Our study suggests early discharge for medicine patients is a priority among academic institutions. Hospitalist and general internal medicine physician leaders in our study generally attributed delayed discharges to external factors, particularly unavailability of postacute care facilities and transportation delays. Having issues with finding postacute care placements is consistent with previous findings by Selker et al.¹⁵ and Carey et al.⁸ This is despite the 20-year difference between Selker et al.’s study and the current study, reflecting a continued opportunity for improvement, including stronger partnerships with local and regional postacute care facilities to expedite care transition and stronger discharge-planning efforts early in the admission process. Efforts in postacute care placement may be particularly important for Medicaid-insured and uninsured patients.

Our responders, hospitalist and internal medicine physician leaders, did not perceive the additional responsibilities of teaching and supervising trainees to be factors that significantly delayed patient discharge. This is in contrast to previous studies, which attributed delays in discharge to prolonged clinical decision-making related to teaching and supervision.^4-6,8 This discrepancy may be due to the fact that we only surveyed single physician leaders at each institution and not residents. Our finding warrants further investigation to understand the degree to which resident skills may impact discharge planning and processes.

Institutions represented in our study have attempted a variety of initiatives promoting earlier discharge, with varying levels of perceived success. Initiatives perceived to be the most effective by hospital leaders centered on 2 main areas: (1) changing individual provider practice and (2) anticipatory discharge preparation. Interestingly, this is in discordance with the main factors labeled as causing delays in discharges, such as obtaining postacute care beds, busy case managers, and competing demands on primary teams. We hypothesize this may be because such changes require organization- or system-level changes and are perceived as more arduous than changes at the individual level. In addition, changes to individual provider behavior may be more cost- and time-effective than more systemic initiatives.

Our findings are consistent with the work published by Wertheimer and colleagues,¹¹ who show that additional afternoon interdisciplinary rounds can help identify patients who may be discharged before noon the next day. In their study, identifying such patients in advance improved the overall early-discharge rate the following day.

Our findings should be interpreted in light of several limitations. Our survey only considers the perspectives of hospitalist and general internal medicine physician leaders at academic medical centers that are part of the Vizient Inc. collaborative. They do not represent all academic or community-based medical centers. Although the perceived effectiveness of some initiatives was high, we did not collect empirical data to support these claims or to determine which initiative had the greatest relative impact on discharge timeliness. Lastly, we did not obtain resident, nursing, or case manager perspectives on discharge practices. Given their roles as frontline providers, we may have missed these alternative perspectives.

Our study shows there is a strong interest in increasing early discharges in an effort to improve hospital throughput and patient flow.

Acknowledgments

The authors thank all participants who completed the survey and Danielle Carrier at Vizient Inc. (formally University HealthSystem Consortium) for her assistance in obtaining data.

Disclosures

Hemali Patel, Margaret Fang, Michelle Mourad, Adrienne Green, Ryan Murphy, and James Harrison report no conflicts of interest. At the time the research was conducted, Robert Wachter reported that he is a member of the Lucian Leape Institute at the National Patient Safety Foundation (no compensation except travel expenses); recently chaired an advisory board to England’s National Health Service (NHS) reviewing the NHS’s digital health strategy (no compensation except travel expenses); has a contract with UCSF from the Agency for Healthcare Research and Quality to edit a patient-safety website; receives compensation from John Wiley & Sons for writing a blog; receives royalties from Lippincott Williams & Wilkins and McGraw-Hill Education for writing and/or editing several books; receives stock options for serving on the board of Acuity Medical Management Systems; receives a yearly stipend for serving on the board of The Doctors Company; serves on the scientific advisory boards for amino.com, PatientSafe Solutions Inc., Twine, and EarlySense (for which he receives stock options); has a small royalty stake in CareWeb, a hospital communication tool developed at UCSF; and holds the Marc and Lynne Benioff Endowed Chair in Hospital Medicine and the Holly Smith Distinguished Professorship in Science and Medicine at UCSF.

Pleural effusion can occur in myriad conditions including infection, heart failure, liver disease, and cancer.¹ Consequently, physicians from many disciplines routinely encounter both inpatients and outpatients with this diagnosis. Often, evaluation and treatment require thoracentesis to obtain fluid for analysis or symptom relief.

Although historically performed at the bedside without imaging guidance or intraprocedural monitoring, thoracentesis performed in this fashion carries considerable risk of complications. In fact, it has 1 of the highest rates of iatrogenic pneumothorax among bedside procedures.² However, recent advances in practice and adoption of newer technologies have helped to mitigate risks associated with this procedure. These advances are relevant because approximately 50% of thoracenteses are still performed at the bedside.³ In this review, we aim to identify the most recent key practices that enhance the safety and the effectiveness of thoracentesis for practicing clinicians.

Information Sources and Search Strategy

With the assistance of a research librarian, we performed a systematic search of PubMed-indexed articles from January 1, 2000 to September 30, 2015. Articles were identified using search terms such as thoracentesis, pleural effusion, safety, medical error, adverse event, and ultrasound in combination with Boolean operators. Of note, as thoracentesis is indexed as a subgroup of paracentesis in PubMed, this term was also included to increase the sensitivity of the search. The full search strategy is available in the Appendix. Any references cited in this review outside of the date range of our search are provided only to give relevant background information or establish the origin of commonly performed practices.

Study Eligibility and Selection Criteria

Studies were included if they reported clinical aspects related to thoracentesis. We defined clinical aspects as those strategies that focused on operator training, procedural techniques, technology, management, or prevention of complications. Non-English language articles, animal studies, case reports, conference proceedings, and abstracts were excluded. As our intention was to focus on the contemporary advances related to thoracentesis performance, (eg, ultrasound [US]), our search was limited to studies published after the year 2000. Two authors, Drs. Schildhouse and Lai independently screened studies to determine inclusion, excluding studies with weak methodology, very small sample sizes, and those only tangentially related to our aim. Disagreements regarding study inclusion were resolved by consensus. Drs. Lai, Barsuk, and Mourad identified additional studies by hand review of reference lists and content experts (Figure 1).

Conceptual Framework

All selected articles were categorized by temporal relationship to thoracentesis as pre-, intra-, or postprocedure. Pre-procedural topics were those outcomes that had been identified and addressed before attempting thoracentesis, such as physician training or perceived risks of harm. Intraprocedural considerations included aspects such as use of bedside US, pleural manometry, and large-volume drainage. Finally, postprocedural factors were those related to evaluation after thoracentesis, such as follow-up imaging. This conceptual framework is outlined in Figure 2.

The PubMed search returned a total of 1170 manuscripts, of which 56 articles met inclusion criteria. Four additional articles were identified by experts and included in the study.^4-7 Therefore, 60 articles were identified and included in this review. Study designs included cohort studies, case control studies, systematic reviews, meta-analyses, narrative reviews, consensus guidelines, and randomized controlled trials. A summary of all included articles by topic can be found in the Table.
 

PRE-PROCEDURAL CONSIDERATIONS

Physician Training

Studies indicate that graduate medical education may not adequately prepare clinicians to perform thoracentesis.⁸ In fact, residents have the least exposure and confidence in performing thoracentesis when compared to other bedside procedures.^9,10 In 1 survey, 69% of medical trainees desired more exposure to procedures, and 98% felt that procedural skills were important to master.¹¹ Not surprisingly, then, graduating internal medicine residents perform poorly when assessed on a thoracentesis simulator.¹²

Supplemental training outside of residency is useful to develop and maintain skills for thoracentesis, such as simulation with direct observation in a zero-risk environment. In 1 study, “simulation-based mastery learning” combined an educational video presentation with repeated, deliberate practice on a simulator until procedural competence was acquired, over two 2-hour sessions. In this study, 40 third-year medicine residents demonstrated a 71% improvement in clinical skills performance after course completion, with 93% achieving a passing score. The remaining 7% also achieved passing scores with extra practice time.¹² Others have built upon the concept of simulation-based training. For instance, 2 studies suggest that use of a simulation-based curriculum improved both thoracentesis knowledge and performance skills in a 3-hour session.^13,14 Similarly, 1 prospective study reported that a half-day thoracentesis workshop using simulation and 1:1 direct observation successfully lowered pneumothorax rates from 8.6% to 1.8% in a group of practicing clinicians. Notably, additional interventions including use of bedside US, limiting operators to a focused group, and standardization of equipment were also a part of this quality improvement initiative.⁷ Although repetition is required to gain proficiency when using a simulator, performance and confidence appear to plateau with only 4 simulator trials. In medical students, improvements derived through simulator-based teaching were sustained when retested 6 months following training.¹⁵

An instrument to ensure competency is necessary, given variability in procedural experience among both new graduates and practicing physicians,. Our search did not identify any clinically validated tools that adequately assessed thoracentesis performance. However, some have been proposed¹⁶ and 1 validated in a simulation environment.¹² Regarding the incorporation of US for effusion markup, 1 validated tool used an 11-domain assessment covering knowledge of US machine manipulation, recognition of images with common pleural effusion characteristics, and performance of thoracic US with puncture-site marking on a simulator. When used on 22 participants, scores with the tool could reliably differentiate between novice, intermediate, and advanced groups (P < 0.0001).¹⁷

Patient Selection

Coagulopathies and Anticoagulation. Historically, the accepted cutoff for performing thoracentesis is an international normalized ratio (INR) less than 1.5 and a platelet count greater than 50,000/µL. McVay et al.¹⁸ first showed in 1991 that use of these cutoffs was associated with low rates of periprocedural bleeding, leading to endorsement in the British Thoracic Society (BTS) Pleural Disease Guideline 2010.¹⁹ Other recommendations include the 2012 Society for Interventional Radiology guidelines that endorse correction of an INR greater than 2, or platelets less than 50,000/µL, based almost exclusively on expert opinion.⁵

However, data suggest that thoracentesis may be safely performed outside these parameters. For instance, a prospective study of approximately 9000 thoracenteses over 12 years found that patients with an INR of 1.5-2.9 or platelets of 20,000 - 49,000/µL experienced rates of bleeding complications similar to those with normal values.²⁰ Similarly, a 2014 review²¹ found that the overall risk of hemorrhage during thoracentesis in the setting of moderate coagulopathy (defined as an INR of 1.5 - 3 or platelets of 25,000-50,000/µL), was not increased. In 1 retrospective study of more than 1000 procedures, no differences in hemorrhagic events were noted in patients with bleeding diatheses that received prophylactic fresh frozen plasma or platelets vs. those who did not.²² Of note, included studies used a variety of criteria to define a hemorrhagic complication, which included: an isolated 2 g/dL or more decrement in hemoglobin, presence of bloody fluid on repeat tap with associated hemoglobin decrement, rapid re-accumulation of fluid with a hemoglobin decrement, or transfusion of 2 units or more of whole blood.

Whether it is safe to perform thoracentesis on patients taking antiplatelet therapy is less well understood. Although data are limited, a few small-scale studies^23,24 suggest that hemorrhagic complications following thoracentesis in patients receiving clopidogrel are comparable to the general population. We found no compelling data regarding the safety of thoracentesis in the setting of direct oral anticoagulants, heparin, low-molecular weight heparin, or intravenous direct thrombin inhibitors. Current practice is to generally avoid thoracentesis while these therapeutic anticoagulants are used.

Invasive mechanical ventilation. Pleural effusion is common in patients in the intensive care unit, including those requiring mechanical ventilation.²⁵ Thoracentesis in this population is clinically important: fluid analysis in 1 study was shown to aid the diagnosis in 45% of cases and changes in treatment in 33%.²⁶ However, clinicians may be reluctant to perform thoracentesis on patients who require mechanical ventilation, given the perception of a greater risk of pneumothorax from positive pressure ventilation.

Despite this concern, a 2011 meta-analysis including 19 studies and more than 1100 patients revealed rates of pneumothorax and hemothorax comparable to nonventilated patients.²⁵ Furthermore, a 2015 prospective study that examined thoracentesis in 1377 mechanically ventilated patients revealed no difference in complication rates as well.²⁰ Therefore, evidence suggests that performance of thoracentesis in mechanically ventilated patients is not contraindicated.

Skin Disinfection and Antisepsis Precautions

The 2010 BTS guidelines list empyema and wound infection as possible complications of thoracentesis.¹⁹ However, no data regarding incidence are provided. Additionally, an alcohol-based skin cleanser (such as 2% chlorhexidine gluconate/70% isopropyl alcohol), along with sterile gloves, field, and dressing are suggested as precautionary measures.¹⁹ In 1 single-center registry of 2489 thoracenteses performed using alcohol or iodine-based antiseptic and sterile drapes, no postprocedure infections were identified.²⁷ Of note, we did not find other studies (including case reports) that reported either incidence or rate of infectious complications such as wound infection and empyema. In an era of modern skin antiseptics that have effectively reduced complications such as catheter-related bloodstream infection,²⁸ the incidence of this event is thus likely to be low.

INTRAPROCEDURAL CONSIDERATIONS

Use of Bedside Ultrasound

Portable US has particular advantages for evaluation of pleural effusion vs other imaging modalities. Compared with computerized tomography (CT), bedside US offers similar performance but is less costly, avoids both radiation exposure and need for patient transportation, and provides results instantaneously.^29,30 Compared to chest x-ray (CXR), US is more sensitive at detecting the presence, volume, and characteristics of pleural fluid^30,31 and can be up to 100% sensitive for effusions greater than 100 mL.²⁹ Furthermore, whereas CXR typically requires 200 mL of fluid to be present for detection of an effusion, US can reliably detect as little as 20 mL of fluid.²⁹ When US was used to confirm thoracentesis puncture sites in a study involving 30 physicians of varying experience and 67 consecutive patients, 15% of sites found by clinical exam were inaccurate (less than 10 mm fluid present), 10% were at high risk for organ puncture, and a suitable fluid pocket was found 54% of times when exam could not.⁴

A 2010 meta-analysis of 24 studies and 6605 thoracenteses estimated the overall rate of pneumothorax at 6%; however, procedures performed with US guidance were associated with a 70% reduced risk of this event (odds ratio, 0.30; 95% confidence interval, 0.20 - 0.70).³² In a 2014 randomized control trial of 160 patients that compared thoracentesis with US guidance for site marking vs no US use, 10 pneumothoraces occurred in the control group vs 1 in the US group (12.5% vs 1.25%, P = 0.009).³³ Similarly, another retrospective review of 445 consecutive patients with malignant effusions revealed a pneumothorax rate of 0.97% using US in real time during needle insertion compared to 8.89% for unguided thoracenteses (P < 0.0001).³⁴ Several other studies using US guidance for either site markup or in real time reported similar pneumothorax rates, ranging from 1.1% - 4.8%.^35-37 However, it is unclear if real-time US specifically provides an additive effect vs site marking alone, as no studies directly comparing the 2 methods were found.

Benefits of US also include a higher rate of procedural success, with 1 study demonstrating a 99% success rate when using US vs. 90% without (P = 0.030).³³ A larger volume of fluid removed has been observed with US use as well, and methods have been described using fluid-pocket depth to guide puncture site localization and maximize drainage.³⁸ Finally, US use for thoracentesis has been associated with lower costs and length of stay.^39,40

Intercostal Artery Localization

Although rare (incidence, 0.18%-2%^20,21,39), the occurrence of hemothorax following thoracentesis is potentially catastrophic. This serious complication is often caused by laceration of the intercostal artery (ICA) or 1 of its branches during needle insertion.⁴¹

While risk of injury is theoretically reduced by needle insertion superior to the rib, studies using cadaver dissection and 3D angiography show significant tortuosity of the ICA.^6,41-43 The degree of tortuosity is increased within 6 cm of the midline, in more cephalad rib spaces, and in the elderly (older than 60 years).^41-43 Furthermore, 1 cadaveric study also demonstrated the presence of arterial collaterals branching off the ICA at multiple intercostal spaces, ranging between 8 cm and 11 cm from the midline.⁴¹ This anatomic variability may explain why some have observed low complication and hemothorax rates with an extreme lateral approach.³⁵ Bedside US with color flow Doppler imaging has been used to identify the ICA, with 88% sensitivity compared to CT imaging while adding little to exam time.^44,45 Of note, a 37% drop in the rate of hemothorax was observed in 1 study with routine US guidance alone.³⁹

Pleural Pressure Monitoring and Large-Volume Thoracentesis

While normal intrapleural pressures are approximately -5 to -10 cm H₂O,⁴⁶ the presence of a pleural effusion creates a complex interaction between fluid, compressed lung, and chest wall that can increase these pressures.⁴⁷ During drainage of an effusion, pleural pressures may rapidly drop, provoking re-expansion pulmonary edema (REPE). While rare (0 -1%), clinically-diagnosed REPE is a serious complication that can lead to rapid respiratory failure and death.^20,48 REPE is postulated to be caused by increased capillary permeability resulting from inflammation, driven by rapid re-inflation of the lung when exposed to highly negative intrapleural pressures.^47,49

Measurement of intrapleural pressure using a water manometer during thoracentesis may minimize REPE by terminating fluid drainage when intrapleural pressure begins to drop rapidly.^50,51 A cutoff of -20 cm H₂O has been cited repeatedly as safe since being suggested by Light in 1980, but this is based on animal models.^50,52 In 1 prospective study of 185 thoracenteses in which manometry was performed, 15% of patients had intrapleural pressure drop to less than -20 cm H₂O (at which point the procedure was terminated) but suffered no REPE.⁵⁰

Manometry is valuable in the identification of an unexpandable or trapped lung when pleural pressures drop rapidly with only minimal fluid volume removal.^47,53 Other findings correlated with an unexpandable lung include a negative opening pressure⁴⁷ and large fluctuations in pressure during the respiratory cycle.⁵⁴

While development of symptoms (eg, chest pain, cough, or dyspnea) is often used as a surrogate, the correlation between intrapleural pressure and patient symptoms is inconsistent and not a reliable proxy.⁵⁵ One study found that 22% of patients with chest pain during thoracentesis had intrapleural pressures lower than -20 cm H₂O compared with 8.6% of asymptomatic patients,⁵⁶ but it is unclear if the association is causal.

Thoracentesis is often performed for symptomatic relief and removal of large fluid volume. However, it remains common to halt fluid removal after 1.5 L, a threshold endorsed by BTS.¹⁹ While some investigators have suggested that removal of 2 L or more of pleural fluid does not compromise safety,^57,58 a 4- to 5-fold rise in the risk of pneumothorax was noted in 2 studies.^20,59 when more than 1.5 L of fluid was removed. The majority of these may be related to pneumothorax ex vacuo, a condition in which fluid is drained from the chest, but the lung is unable to expand and fill the space (eg, “trapped lung”), resulting in a persistent pneumothorax. This condition generally does not require treatment.⁶⁰ When manometry is employed at 200-mL intervals with termination at an intrapleural pressure of less than 20 mm H₂O, drainage of 3 L or more has been reported with low rates of pneumothorax and very low rates of REPE.^50,51 However, whether this is cause and effect is unknown because REPE is rare, and more work is needed to determine the role of manometry for its prevention.

POSTPROCEDURAL CONSIDERATIONS

Postprocedure Imaging

Performing an upright CXR following thoracentesis is a practice that remains routinely done by many practitioners to monitor for complications. Such imaging was also endorsed by the American Thoracic Society guidelines.⁶¹ However, more recent data question the utility of this practice. Multiple studies have confirmed that post-thoracentesis CXR is unnecessary unless clinical suspicion for pneumothorax or REPE is present.^36,58,62,63 The BTS guidelines also advocate this approach.¹⁹ Interestingly, a potentially more effective way to screen for postprocedure complications is through bedside US, which has been shown to be more sensitive than CXR in detecting pneumothorax.⁶⁴ In 1 study of 185 patients, bedside US demonstrated a sensitivity of 88% and a specificity of 97% for diagnosing pneumothorax in patients with adequate quality scans, with positive and negative likelihood ratios of 55 and 0.17, respectively.⁶⁵

Thoracentesis remains a core procedural skill for hospitalists, critical care physicians, and emergency physicians. It is the foundational component when investigating and treating pleural effusions. When the most current training, techniques, and technology are used, data suggest this procedure is safe to perform at the bedside. Our review highlights these strategies and evaluates which aspects might be most applicable to clinical practice.

Our findings have several implications for those who perform this procedure. First, appropriate training is central to procedural safety, and both simulation and direct observation by procedural experts have been shown by multiple investigators to improve knowledge and skill. This training should integrate the use of US in performing a focused thoracic exam.

Second, recommendations regarding coagulopathy and a “safe cutoff” of an INR less than 1.5 or platelets greater than 50,000/µL had limited evidentiary support. Rather, multiple studies suggest no difference in bleeding risk following thoracentesis with an INR as high as 3.0 and platelets greater than 25,000/µL. Furthermore, prophylactic transfusion with fresh frozen plasma or platelets before thoracentesis did not alter bleeding risk and exposes patients to transfusion complications. Thus, routine use of this practice can no longer be recommended. Third, further research is needed to understand the bleeding risk for patients on antiplatelet medications, heparin products, and also direct oral anticoagulants, given the growing popularity in their use and the potential consequences of even temporary cessation. Regarding patients on mechanical ventilation, thoracentesis demonstrated no difference in complication rates vs. the general population, and its performance in this population is encouraged when clinically indicated.

Intraprocedural considerations include the use of bedside US. Due to multiple benefits including effusion characterization, puncture site localization, and significantly lower rates of pneumothorax, the standard of care should be to perform thoracentesis with US guidance. Both use of US to mark an effusion immediately prior to puncture or in real time during needle insertion demonstrated benefit; however, it is unclear if 1 method is superior because no direct comparison studies were found. Further work is needed to investigate this potential.

Our review suggests that the location and course of the ICA is variable, especially near the midline, in the elderly, and in higher intercostal spaces, leaving it vulnerable to laceration. We recommend physicians only attempt thoracentesis at least 6 cm lateral to the midline due to ICA tortuosity and, ideally, 12 cm lateral, to avoid the presence of collaterals. Although only 2 small-scale studies were found pertaining to the use of US in identifying the ICA, we encourage physicians to consider learning how to screen for its presence as a part of their routine thoracic US exam in the area underlying the planned puncture site.

Manometry is beneficial because it can diagnose a nonexpandable lung and allows for pleural pressure monitoring.^52,53 A simple U-shaped manometer can be constructed from intravenous tubing included in most thoracentesis kits, which adds little to overall procedure time. While low rates of REPE have been observed when terminating thoracentesis if pressures drop below -20 cm H₂O or chest pain develops, neither measure appears to have reliable predictive value, limiting clinical utility. Further work is required to determine if a “safe pressure cutoff” exists. In general, we recommend the use of manometry when a nonexpandable (trapped) lung is suspected, because large drops in intrapleural pressure, a negative opening pressure, and respiratory variation can help confirm the diagnosis and avoid pneumothorax ex vacuo or unnecessary procedures in the future. As this condition appears to be more common in the setting of larger effusions, use of manometry when large-volume thoracenteses are planned is also reasonable.

Postprocedurally, routine imaging after thoracentesis is not recommended unless there is objective concern for complication. When indicated, bedside US is better positioned for this role compared with CXR, because it is more sensitive in detecting pneumothorax, provides instantaneous results, and avoids radiation exposure.

Our review has limitations. First, we searched only for articles between defined time periods, restricted our search to a single database, and excluded non-English articles. This has the potential to introduce selection bias, as nonprimary articles that fall within our time restrictions may cite older studies that are outside our search range. To minimize this effect, we performed a critical review of all included studies, especially nonprimary articles. Second, despite the focus of our search strategy to identify any articles related to patient safety and adverse events, we cannot guarantee that all relevant articles for any particular complication or risk factor were captured given the lack of more specific search terms. Third, although we performed a systematic search of the literature, we did not perform a formal systematic review or formally grade included studies. As the goal of our review was to categorize and operationalize clinical aspects, this approach was necessary, and we acknowledge that the quality of studies is variable. Lastly, we aimed to generate clinical recommendations for physicians performing thoracentesis at the bedside; others reviewing this literature may find or emphasize different aspects relevant to practice outside this setting.

In conclusion, evaluation and treatment of pleural effusions with bedside thoracentesis is an important skill for physicians of many disciplines. The evidence presented in this review will help inform the process and ensure patient safety. Physicians should consider incorporating these recommendations into their practice.

Acknowledgments

The authors thank Whitney Townsend, MLIS, health sciences informationist, for assistance with serial literature searches.

Disclosure

Nothing to report.

Pleural effusion can occur in myriad conditions including infection, heart failure, liver disease, and cancer.¹ Consequently, physicians from many disciplines routinely encounter both inpatients and outpatients with this diagnosis. Often, evaluation and treatment require thoracentesis to obtain fluid for analysis or symptom relief.

Although historically performed at the bedside without imaging guidance or intraprocedural monitoring, thoracentesis performed in this fashion carries considerable risk of complications. In fact, it has 1 of the highest rates of iatrogenic pneumothorax among bedside procedures.² However, recent advances in practice and adoption of newer technologies have helped to mitigate risks associated with this procedure. These advances are relevant because approximately 50% of thoracenteses are still performed at the bedside.³ In this review, we aim to identify the most recent key practices that enhance the safety and the effectiveness of thoracentesis for practicing clinicians.

Information Sources and Search Strategy

With the assistance of a research librarian, we performed a systematic search of PubMed-indexed articles from January 1, 2000 to September 30, 2015. Articles were identified using search terms such as thoracentesis, pleural effusion, safety, medical error, adverse event, and ultrasound in combination with Boolean operators. Of note, as thoracentesis is indexed as a subgroup of paracentesis in PubMed, this term was also included to increase the sensitivity of the search. The full search strategy is available in the Appendix. Any references cited in this review outside of the date range of our search are provided only to give relevant background information or establish the origin of commonly performed practices.

Study Eligibility and Selection Criteria

Studies were included if they reported clinical aspects related to thoracentesis. We defined clinical aspects as those strategies that focused on operator training, procedural techniques, technology, management, or prevention of complications. Non-English language articles, animal studies, case reports, conference proceedings, and abstracts were excluded. As our intention was to focus on the contemporary advances related to thoracentesis performance, (eg, ultrasound [US]), our search was limited to studies published after the year 2000. Two authors, Drs. Schildhouse and Lai independently screened studies to determine inclusion, excluding studies with weak methodology, very small sample sizes, and those only tangentially related to our aim. Disagreements regarding study inclusion were resolved by consensus. Drs. Lai, Barsuk, and Mourad identified additional studies by hand review of reference lists and content experts (Figure 1).

Conceptual Framework

All selected articles were categorized by temporal relationship to thoracentesis as pre-, intra-, or postprocedure. Pre-procedural topics were those outcomes that had been identified and addressed before attempting thoracentesis, such as physician training or perceived risks of harm. Intraprocedural considerations included aspects such as use of bedside US, pleural manometry, and large-volume drainage. Finally, postprocedural factors were those related to evaluation after thoracentesis, such as follow-up imaging. This conceptual framework is outlined in Figure 2.

The PubMed search returned a total of 1170 manuscripts, of which 56 articles met inclusion criteria. Four additional articles were identified by experts and included in the study.^4-7 Therefore, 60 articles were identified and included in this review. Study designs included cohort studies, case control studies, systematic reviews, meta-analyses, narrative reviews, consensus guidelines, and randomized controlled trials. A summary of all included articles by topic can be found in the Table.
 

PRE-PROCEDURAL CONSIDERATIONS

Physician Training

Studies indicate that graduate medical education may not adequately prepare clinicians to perform thoracentesis.⁸ In fact, residents have the least exposure and confidence in performing thoracentesis when compared to other bedside procedures.^9,10 In 1 survey, 69% of medical trainees desired more exposure to procedures, and 98% felt that procedural skills were important to master.¹¹ Not surprisingly, then, graduating internal medicine residents perform poorly when assessed on a thoracentesis simulator.¹²

Supplemental training outside of residency is useful to develop and maintain skills for thoracentesis, such as simulation with direct observation in a zero-risk environment. In 1 study, “simulation-based mastery learning” combined an educational video presentation with repeated, deliberate practice on a simulator until procedural competence was acquired, over two 2-hour sessions. In this study, 40 third-year medicine residents demonstrated a 71% improvement in clinical skills performance after course completion, with 93% achieving a passing score. The remaining 7% also achieved passing scores with extra practice time.¹² Others have built upon the concept of simulation-based training. For instance, 2 studies suggest that use of a simulation-based curriculum improved both thoracentesis knowledge and performance skills in a 3-hour session.^13,14 Similarly, 1 prospective study reported that a half-day thoracentesis workshop using simulation and 1:1 direct observation successfully lowered pneumothorax rates from 8.6% to 1.8% in a group of practicing clinicians. Notably, additional interventions including use of bedside US, limiting operators to a focused group, and standardization of equipment were also a part of this quality improvement initiative.⁷ Although repetition is required to gain proficiency when using a simulator, performance and confidence appear to plateau with only 4 simulator trials. In medical students, improvements derived through simulator-based teaching were sustained when retested 6 months following training.¹⁵

An instrument to ensure competency is necessary, given variability in procedural experience among both new graduates and practicing physicians,. Our search did not identify any clinically validated tools that adequately assessed thoracentesis performance. However, some have been proposed¹⁶ and 1 validated in a simulation environment.¹² Regarding the incorporation of US for effusion markup, 1 validated tool used an 11-domain assessment covering knowledge of US machine manipulation, recognition of images with common pleural effusion characteristics, and performance of thoracic US with puncture-site marking on a simulator. When used on 22 participants, scores with the tool could reliably differentiate between novice, intermediate, and advanced groups (P < 0.0001).¹⁷

Patient Selection

Coagulopathies and Anticoagulation. Historically, the accepted cutoff for performing thoracentesis is an international normalized ratio (INR) less than 1.5 and a platelet count greater than 50,000/µL. McVay et al.¹⁸ first showed in 1991 that use of these cutoffs was associated with low rates of periprocedural bleeding, leading to endorsement in the British Thoracic Society (BTS) Pleural Disease Guideline 2010.¹⁹ Other recommendations include the 2012 Society for Interventional Radiology guidelines that endorse correction of an INR greater than 2, or platelets less than 50,000/µL, based almost exclusively on expert opinion.⁵

However, data suggest that thoracentesis may be safely performed outside these parameters. For instance, a prospective study of approximately 9000 thoracenteses over 12 years found that patients with an INR of 1.5-2.9 or platelets of 20,000 - 49,000/µL experienced rates of bleeding complications similar to those with normal values.²⁰ Similarly, a 2014 review²¹ found that the overall risk of hemorrhage during thoracentesis in the setting of moderate coagulopathy (defined as an INR of 1.5 - 3 or platelets of 25,000-50,000/µL), was not increased. In 1 retrospective study of more than 1000 procedures, no differences in hemorrhagic events were noted in patients with bleeding diatheses that received prophylactic fresh frozen plasma or platelets vs. those who did not.²² Of note, included studies used a variety of criteria to define a hemorrhagic complication, which included: an isolated 2 g/dL or more decrement in hemoglobin, presence of bloody fluid on repeat tap with associated hemoglobin decrement, rapid re-accumulation of fluid with a hemoglobin decrement, or transfusion of 2 units or more of whole blood.

Whether it is safe to perform thoracentesis on patients taking antiplatelet therapy is less well understood. Although data are limited, a few small-scale studies^23,24 suggest that hemorrhagic complications following thoracentesis in patients receiving clopidogrel are comparable to the general population. We found no compelling data regarding the safety of thoracentesis in the setting of direct oral anticoagulants, heparin, low-molecular weight heparin, or intravenous direct thrombin inhibitors. Current practice is to generally avoid thoracentesis while these therapeutic anticoagulants are used.

Invasive mechanical ventilation. Pleural effusion is common in patients in the intensive care unit, including those requiring mechanical ventilation.²⁵ Thoracentesis in this population is clinically important: fluid analysis in 1 study was shown to aid the diagnosis in 45% of cases and changes in treatment in 33%.²⁶ However, clinicians may be reluctant to perform thoracentesis on patients who require mechanical ventilation, given the perception of a greater risk of pneumothorax from positive pressure ventilation.

Despite this concern, a 2011 meta-analysis including 19 studies and more than 1100 patients revealed rates of pneumothorax and hemothorax comparable to nonventilated patients.²⁵ Furthermore, a 2015 prospective study that examined thoracentesis in 1377 mechanically ventilated patients revealed no difference in complication rates as well.²⁰ Therefore, evidence suggests that performance of thoracentesis in mechanically ventilated patients is not contraindicated.

Skin Disinfection and Antisepsis Precautions

The 2010 BTS guidelines list empyema and wound infection as possible complications of thoracentesis.¹⁹ However, no data regarding incidence are provided. Additionally, an alcohol-based skin cleanser (such as 2% chlorhexidine gluconate/70% isopropyl alcohol), along with sterile gloves, field, and dressing are suggested as precautionary measures.¹⁹ In 1 single-center registry of 2489 thoracenteses performed using alcohol or iodine-based antiseptic and sterile drapes, no postprocedure infections were identified.²⁷ Of note, we did not find other studies (including case reports) that reported either incidence or rate of infectious complications such as wound infection and empyema. In an era of modern skin antiseptics that have effectively reduced complications such as catheter-related bloodstream infection,²⁸ the incidence of this event is thus likely to be low.

INTRAPROCEDURAL CONSIDERATIONS

Use of Bedside Ultrasound

Portable US has particular advantages for evaluation of pleural effusion vs other imaging modalities. Compared with computerized tomography (CT), bedside US offers similar performance but is less costly, avoids both radiation exposure and need for patient transportation, and provides results instantaneously.^29,30 Compared to chest x-ray (CXR), US is more sensitive at detecting the presence, volume, and characteristics of pleural fluid^30,31 and can be up to 100% sensitive for effusions greater than 100 mL.²⁹ Furthermore, whereas CXR typically requires 200 mL of fluid to be present for detection of an effusion, US can reliably detect as little as 20 mL of fluid.²⁹ When US was used to confirm thoracentesis puncture sites in a study involving 30 physicians of varying experience and 67 consecutive patients, 15% of sites found by clinical exam were inaccurate (less than 10 mm fluid present), 10% were at high risk for organ puncture, and a suitable fluid pocket was found 54% of times when exam could not.⁴

A 2010 meta-analysis of 24 studies and 6605 thoracenteses estimated the overall rate of pneumothorax at 6%; however, procedures performed with US guidance were associated with a 70% reduced risk of this event (odds ratio, 0.30; 95% confidence interval, 0.20 - 0.70).³² In a 2014 randomized control trial of 160 patients that compared thoracentesis with US guidance for site marking vs no US use, 10 pneumothoraces occurred in the control group vs 1 in the US group (12.5% vs 1.25%, P = 0.009).³³ Similarly, another retrospective review of 445 consecutive patients with malignant effusions revealed a pneumothorax rate of 0.97% using US in real time during needle insertion compared to 8.89% for unguided thoracenteses (P < 0.0001).³⁴ Several other studies using US guidance for either site markup or in real time reported similar pneumothorax rates, ranging from 1.1% - 4.8%.^35-37 However, it is unclear if real-time US specifically provides an additive effect vs site marking alone, as no studies directly comparing the 2 methods were found.

Benefits of US also include a higher rate of procedural success, with 1 study demonstrating a 99% success rate when using US vs. 90% without (P = 0.030).³³ A larger volume of fluid removed has been observed with US use as well, and methods have been described using fluid-pocket depth to guide puncture site localization and maximize drainage.³⁸ Finally, US use for thoracentesis has been associated with lower costs and length of stay.^39,40

Intercostal Artery Localization

Although rare (incidence, 0.18%-2%^20,21,39), the occurrence of hemothorax following thoracentesis is potentially catastrophic. This serious complication is often caused by laceration of the intercostal artery (ICA) or 1 of its branches during needle insertion.⁴¹

While risk of injury is theoretically reduced by needle insertion superior to the rib, studies using cadaver dissection and 3D angiography show significant tortuosity of the ICA.^6,41-43 The degree of tortuosity is increased within 6 cm of the midline, in more cephalad rib spaces, and in the elderly (older than 60 years).^41-43 Furthermore, 1 cadaveric study also demonstrated the presence of arterial collaterals branching off the ICA at multiple intercostal spaces, ranging between 8 cm and 11 cm from the midline.⁴¹ This anatomic variability may explain why some have observed low complication and hemothorax rates with an extreme lateral approach.³⁵ Bedside US with color flow Doppler imaging has been used to identify the ICA, with 88% sensitivity compared to CT imaging while adding little to exam time.^44,45 Of note, a 37% drop in the rate of hemothorax was observed in 1 study with routine US guidance alone.³⁹

Pleural Pressure Monitoring and Large-Volume Thoracentesis

While normal intrapleural pressures are approximately -5 to -10 cm H₂O,⁴⁶ the presence of a pleural effusion creates a complex interaction between fluid, compressed lung, and chest wall that can increase these pressures.⁴⁷ During drainage of an effusion, pleural pressures may rapidly drop, provoking re-expansion pulmonary edema (REPE). While rare (0 -1%), clinically-diagnosed REPE is a serious complication that can lead to rapid respiratory failure and death.^20,48 REPE is postulated to be caused by increased capillary permeability resulting from inflammation, driven by rapid re-inflation of the lung when exposed to highly negative intrapleural pressures.^47,49

Measurement of intrapleural pressure using a water manometer during thoracentesis may minimize REPE by terminating fluid drainage when intrapleural pressure begins to drop rapidly.^50,51 A cutoff of -20 cm H₂O has been cited repeatedly as safe since being suggested by Light in 1980, but this is based on animal models.^50,52 In 1 prospective study of 185 thoracenteses in which manometry was performed, 15% of patients had intrapleural pressure drop to less than -20 cm H₂O (at which point the procedure was terminated) but suffered no REPE.⁵⁰

Manometry is valuable in the identification of an unexpandable or trapped lung when pleural pressures drop rapidly with only minimal fluid volume removal.^47,53 Other findings correlated with an unexpandable lung include a negative opening pressure⁴⁷ and large fluctuations in pressure during the respiratory cycle.⁵⁴

While development of symptoms (eg, chest pain, cough, or dyspnea) is often used as a surrogate, the correlation between intrapleural pressure and patient symptoms is inconsistent and not a reliable proxy.⁵⁵ One study found that 22% of patients with chest pain during thoracentesis had intrapleural pressures lower than -20 cm H₂O compared with 8.6% of asymptomatic patients,⁵⁶ but it is unclear if the association is causal.

Thoracentesis is often performed for symptomatic relief and removal of large fluid volume. However, it remains common to halt fluid removal after 1.5 L, a threshold endorsed by BTS.¹⁹ While some investigators have suggested that removal of 2 L or more of pleural fluid does not compromise safety,^57,58 a 4- to 5-fold rise in the risk of pneumothorax was noted in 2 studies.^20,59 when more than 1.5 L of fluid was removed. The majority of these may be related to pneumothorax ex vacuo, a condition in which fluid is drained from the chest, but the lung is unable to expand and fill the space (eg, “trapped lung”), resulting in a persistent pneumothorax. This condition generally does not require treatment.⁶⁰ When manometry is employed at 200-mL intervals with termination at an intrapleural pressure of less than 20 mm H₂O, drainage of 3 L or more has been reported with low rates of pneumothorax and very low rates of REPE.^50,51 However, whether this is cause and effect is unknown because REPE is rare, and more work is needed to determine the role of manometry for its prevention.

POSTPROCEDURAL CONSIDERATIONS

Postprocedure Imaging

Performing an upright CXR following thoracentesis is a practice that remains routinely done by many practitioners to monitor for complications. Such imaging was also endorsed by the American Thoracic Society guidelines.⁶¹ However, more recent data question the utility of this practice. Multiple studies have confirmed that post-thoracentesis CXR is unnecessary unless clinical suspicion for pneumothorax or REPE is present.^36,58,62,63 The BTS guidelines also advocate this approach.¹⁹ Interestingly, a potentially more effective way to screen for postprocedure complications is through bedside US, which has been shown to be more sensitive than CXR in detecting pneumothorax.⁶⁴ In 1 study of 185 patients, bedside US demonstrated a sensitivity of 88% and a specificity of 97% for diagnosing pneumothorax in patients with adequate quality scans, with positive and negative likelihood ratios of 55 and 0.17, respectively.⁶⁵

Thoracentesis remains a core procedural skill for hospitalists, critical care physicians, and emergency physicians. It is the foundational component when investigating and treating pleural effusions. When the most current training, techniques, and technology are used, data suggest this procedure is safe to perform at the bedside. Our review highlights these strategies and evaluates which aspects might be most applicable to clinical practice.

Our findings have several implications for those who perform this procedure. First, appropriate training is central to procedural safety, and both simulation and direct observation by procedural experts have been shown by multiple investigators to improve knowledge and skill. This training should integrate the use of US in performing a focused thoracic exam.

Second, recommendations regarding coagulopathy and a “safe cutoff” of an INR less than 1.5 or platelets greater than 50,000/µL had limited evidentiary support. Rather, multiple studies suggest no difference in bleeding risk following thoracentesis with an INR as high as 3.0 and platelets greater than 25,000/µL. Furthermore, prophylactic transfusion with fresh frozen plasma or platelets before thoracentesis did not alter bleeding risk and exposes patients to transfusion complications. Thus, routine use of this practice can no longer be recommended. Third, further research is needed to understand the bleeding risk for patients on antiplatelet medications, heparin products, and also direct oral anticoagulants, given the growing popularity in their use and the potential consequences of even temporary cessation. Regarding patients on mechanical ventilation, thoracentesis demonstrated no difference in complication rates vs. the general population, and its performance in this population is encouraged when clinically indicated.

Intraprocedural considerations include the use of bedside US. Due to multiple benefits including effusion characterization, puncture site localization, and significantly lower rates of pneumothorax, the standard of care should be to perform thoracentesis with US guidance. Both use of US to mark an effusion immediately prior to puncture or in real time during needle insertion demonstrated benefit; however, it is unclear if 1 method is superior because no direct comparison studies were found. Further work is needed to investigate this potential.

Our review suggests that the location and course of the ICA is variable, especially near the midline, in the elderly, and in higher intercostal spaces, leaving it vulnerable to laceration. We recommend physicians only attempt thoracentesis at least 6 cm lateral to the midline due to ICA tortuosity and, ideally, 12 cm lateral, to avoid the presence of collaterals. Although only 2 small-scale studies were found pertaining to the use of US in identifying the ICA, we encourage physicians to consider learning how to screen for its presence as a part of their routine thoracic US exam in the area underlying the planned puncture site.

Manometry is beneficial because it can diagnose a nonexpandable lung and allows for pleural pressure monitoring.^52,53 A simple U-shaped manometer can be constructed from intravenous tubing included in most thoracentesis kits, which adds little to overall procedure time. While low rates of REPE have been observed when terminating thoracentesis if pressures drop below -20 cm H₂O or chest pain develops, neither measure appears to have reliable predictive value, limiting clinical utility. Further work is required to determine if a “safe pressure cutoff” exists. In general, we recommend the use of manometry when a nonexpandable (trapped) lung is suspected, because large drops in intrapleural pressure, a negative opening pressure, and respiratory variation can help confirm the diagnosis and avoid pneumothorax ex vacuo or unnecessary procedures in the future. As this condition appears to be more common in the setting of larger effusions, use of manometry when large-volume thoracenteses are planned is also reasonable.

Postprocedurally, routine imaging after thoracentesis is not recommended unless there is objective concern for complication. When indicated, bedside US is better positioned for this role compared with CXR, because it is more sensitive in detecting pneumothorax, provides instantaneous results, and avoids radiation exposure.

Our review has limitations. First, we searched only for articles between defined time periods, restricted our search to a single database, and excluded non-English articles. This has the potential to introduce selection bias, as nonprimary articles that fall within our time restrictions may cite older studies that are outside our search range. To minimize this effect, we performed a critical review of all included studies, especially nonprimary articles. Second, despite the focus of our search strategy to identify any articles related to patient safety and adverse events, we cannot guarantee that all relevant articles for any particular complication or risk factor were captured given the lack of more specific search terms. Third, although we performed a systematic search of the literature, we did not perform a formal systematic review or formally grade included studies. As the goal of our review was to categorize and operationalize clinical aspects, this approach was necessary, and we acknowledge that the quality of studies is variable. Lastly, we aimed to generate clinical recommendations for physicians performing thoracentesis at the bedside; others reviewing this literature may find or emphasize different aspects relevant to practice outside this setting.

In conclusion, evaluation and treatment of pleural effusions with bedside thoracentesis is an important skill for physicians of many disciplines. The evidence presented in this review will help inform the process and ensure patient safety. Physicians should consider incorporating these recommendations into their practice.

Acknowledgments

The authors thank Whitney Townsend, MLIS, health sciences informationist, for assistance with serial literature searches.

Disclosure

Nothing to report.

Pleural effusion can occur in myriad conditions including infection, heart failure, liver disease, and cancer.¹ Consequently, physicians from many disciplines routinely encounter both inpatients and outpatients with this diagnosis. Often, evaluation and treatment require thoracentesis to obtain fluid for analysis or symptom relief.

Although historically performed at the bedside without imaging guidance or intraprocedural monitoring, thoracentesis performed in this fashion carries considerable risk of complications. In fact, it has 1 of the highest rates of iatrogenic pneumothorax among bedside procedures.² However, recent advances in practice and adoption of newer technologies have helped to mitigate risks associated with this procedure. These advances are relevant because approximately 50% of thoracenteses are still performed at the bedside.³ In this review, we aim to identify the most recent key practices that enhance the safety and the effectiveness of thoracentesis for practicing clinicians.

Information Sources and Search Strategy

With the assistance of a research librarian, we performed a systematic search of PubMed-indexed articles from January 1, 2000 to September 30, 2015. Articles were identified using search terms such as thoracentesis, pleural effusion, safety, medical error, adverse event, and ultrasound in combination with Boolean operators. Of note, as thoracentesis is indexed as a subgroup of paracentesis in PubMed, this term was also included to increase the sensitivity of the search. The full search strategy is available in the Appendix. Any references cited in this review outside of the date range of our search are provided only to give relevant background information or establish the origin of commonly performed practices.

Study Eligibility and Selection Criteria

Studies were included if they reported clinical aspects related to thoracentesis. We defined clinical aspects as those strategies that focused on operator training, procedural techniques, technology, management, or prevention of complications. Non-English language articles, animal studies, case reports, conference proceedings, and abstracts were excluded. As our intention was to focus on the contemporary advances related to thoracentesis performance, (eg, ultrasound [US]), our search was limited to studies published after the year 2000. Two authors, Drs. Schildhouse and Lai independently screened studies to determine inclusion, excluding studies with weak methodology, very small sample sizes, and those only tangentially related to our aim. Disagreements regarding study inclusion were resolved by consensus. Drs. Lai, Barsuk, and Mourad identified additional studies by hand review of reference lists and content experts (Figure 1).

Conceptual Framework

All selected articles were categorized by temporal relationship to thoracentesis as pre-, intra-, or postprocedure. Pre-procedural topics were those outcomes that had been identified and addressed before attempting thoracentesis, such as physician training or perceived risks of harm. Intraprocedural considerations included aspects such as use of bedside US, pleural manometry, and large-volume drainage. Finally, postprocedural factors were those related to evaluation after thoracentesis, such as follow-up imaging. This conceptual framework is outlined in Figure 2.

The PubMed search returned a total of 1170 manuscripts, of which 56 articles met inclusion criteria. Four additional articles were identified by experts and included in the study.^4-7 Therefore, 60 articles were identified and included in this review. Study designs included cohort studies, case control studies, systematic reviews, meta-analyses, narrative reviews, consensus guidelines, and randomized controlled trials. A summary of all included articles by topic can be found in the Table.
 

PRE-PROCEDURAL CONSIDERATIONS

Physician Training

Studies indicate that graduate medical education may not adequately prepare clinicians to perform thoracentesis.⁸ In fact, residents have the least exposure and confidence in performing thoracentesis when compared to other bedside procedures.^9,10 In 1 survey, 69% of medical trainees desired more exposure to procedures, and 98% felt that procedural skills were important to master.¹¹ Not surprisingly, then, graduating internal medicine residents perform poorly when assessed on a thoracentesis simulator.¹²

Supplemental training outside of residency is useful to develop and maintain skills for thoracentesis, such as simulation with direct observation in a zero-risk environment. In 1 study, “simulation-based mastery learning” combined an educational video presentation with repeated, deliberate practice on a simulator until procedural competence was acquired, over two 2-hour sessions. In this study, 40 third-year medicine residents demonstrated a 71% improvement in clinical skills performance after course completion, with 93% achieving a passing score. The remaining 7% also achieved passing scores with extra practice time.¹² Others have built upon the concept of simulation-based training. For instance, 2 studies suggest that use of a simulation-based curriculum improved both thoracentesis knowledge and performance skills in a 3-hour session.^13,14 Similarly, 1 prospective study reported that a half-day thoracentesis workshop using simulation and 1:1 direct observation successfully lowered pneumothorax rates from 8.6% to 1.8% in a group of practicing clinicians. Notably, additional interventions including use of bedside US, limiting operators to a focused group, and standardization of equipment were also a part of this quality improvement initiative.⁷ Although repetition is required to gain proficiency when using a simulator, performance and confidence appear to plateau with only 4 simulator trials. In medical students, improvements derived through simulator-based teaching were sustained when retested 6 months following training.¹⁵

An instrument to ensure competency is necessary, given variability in procedural experience among both new graduates and practicing physicians,. Our search did not identify any clinically validated tools that adequately assessed thoracentesis performance. However, some have been proposed¹⁶ and 1 validated in a simulation environment.¹² Regarding the incorporation of US for effusion markup, 1 validated tool used an 11-domain assessment covering knowledge of US machine manipulation, recognition of images with common pleural effusion characteristics, and performance of thoracic US with puncture-site marking on a simulator. When used on 22 participants, scores with the tool could reliably differentiate between novice, intermediate, and advanced groups (P < 0.0001).¹⁷

Patient Selection

Coagulopathies and Anticoagulation. Historically, the accepted cutoff for performing thoracentesis is an international normalized ratio (INR) less than 1.5 and a platelet count greater than 50,000/µL. McVay et al.¹⁸ first showed in 1991 that use of these cutoffs was associated with low rates of periprocedural bleeding, leading to endorsement in the British Thoracic Society (BTS) Pleural Disease Guideline 2010.¹⁹ Other recommendations include the 2012 Society for Interventional Radiology guidelines that endorse correction of an INR greater than 2, or platelets less than 50,000/µL, based almost exclusively on expert opinion.⁵

However, data suggest that thoracentesis may be safely performed outside these parameters. For instance, a prospective study of approximately 9000 thoracenteses over 12 years found that patients with an INR of 1.5-2.9 or platelets of 20,000 - 49,000/µL experienced rates of bleeding complications similar to those with normal values.²⁰ Similarly, a 2014 review²¹ found that the overall risk of hemorrhage during thoracentesis in the setting of moderate coagulopathy (defined as an INR of 1.5 - 3 or platelets of 25,000-50,000/µL), was not increased. In 1 retrospective study of more than 1000 procedures, no differences in hemorrhagic events were noted in patients with bleeding diatheses that received prophylactic fresh frozen plasma or platelets vs. those who did not.²² Of note, included studies used a variety of criteria to define a hemorrhagic complication, which included: an isolated 2 g/dL or more decrement in hemoglobin, presence of bloody fluid on repeat tap with associated hemoglobin decrement, rapid re-accumulation of fluid with a hemoglobin decrement, or transfusion of 2 units or more of whole blood.

Whether it is safe to perform thoracentesis on patients taking antiplatelet therapy is less well understood. Although data are limited, a few small-scale studies^23,24 suggest that hemorrhagic complications following thoracentesis in patients receiving clopidogrel are comparable to the general population. We found no compelling data regarding the safety of thoracentesis in the setting of direct oral anticoagulants, heparin, low-molecular weight heparin, or intravenous direct thrombin inhibitors. Current practice is to generally avoid thoracentesis while these therapeutic anticoagulants are used.

Invasive mechanical ventilation. Pleural effusion is common in patients in the intensive care unit, including those requiring mechanical ventilation.²⁵ Thoracentesis in this population is clinically important: fluid analysis in 1 study was shown to aid the diagnosis in 45% of cases and changes in treatment in 33%.²⁶ However, clinicians may be reluctant to perform thoracentesis on patients who require mechanical ventilation, given the perception of a greater risk of pneumothorax from positive pressure ventilation.

Despite this concern, a 2011 meta-analysis including 19 studies and more than 1100 patients revealed rates of pneumothorax and hemothorax comparable to nonventilated patients.²⁵ Furthermore, a 2015 prospective study that examined thoracentesis in 1377 mechanically ventilated patients revealed no difference in complication rates as well.²⁰ Therefore, evidence suggests that performance of thoracentesis in mechanically ventilated patients is not contraindicated.

Skin Disinfection and Antisepsis Precautions

The 2010 BTS guidelines list empyema and wound infection as possible complications of thoracentesis.¹⁹ However, no data regarding incidence are provided. Additionally, an alcohol-based skin cleanser (such as 2% chlorhexidine gluconate/70% isopropyl alcohol), along with sterile gloves, field, and dressing are suggested as precautionary measures.¹⁹ In 1 single-center registry of 2489 thoracenteses performed using alcohol or iodine-based antiseptic and sterile drapes, no postprocedure infections were identified.²⁷ Of note, we did not find other studies (including case reports) that reported either incidence or rate of infectious complications such as wound infection and empyema. In an era of modern skin antiseptics that have effectively reduced complications such as catheter-related bloodstream infection,²⁸ the incidence of this event is thus likely to be low.

INTRAPROCEDURAL CONSIDERATIONS

Use of Bedside Ultrasound

Portable US has particular advantages for evaluation of pleural effusion vs other imaging modalities. Compared with computerized tomography (CT), bedside US offers similar performance but is less costly, avoids both radiation exposure and need for patient transportation, and provides results instantaneously.^29,30 Compared to chest x-ray (CXR), US is more sensitive at detecting the presence, volume, and characteristics of pleural fluid^30,31 and can be up to 100% sensitive for effusions greater than 100 mL.²⁹ Furthermore, whereas CXR typically requires 200 mL of fluid to be present for detection of an effusion, US can reliably detect as little as 20 mL of fluid.²⁹ When US was used to confirm thoracentesis puncture sites in a study involving 30 physicians of varying experience and 67 consecutive patients, 15% of sites found by clinical exam were inaccurate (less than 10 mm fluid present), 10% were at high risk for organ puncture, and a suitable fluid pocket was found 54% of times when exam could not.⁴

A 2010 meta-analysis of 24 studies and 6605 thoracenteses estimated the overall rate of pneumothorax at 6%; however, procedures performed with US guidance were associated with a 70% reduced risk of this event (odds ratio, 0.30; 95% confidence interval, 0.20 - 0.70).³² In a 2014 randomized control trial of 160 patients that compared thoracentesis with US guidance for site marking vs no US use, 10 pneumothoraces occurred in the control group vs 1 in the US group (12.5% vs 1.25%, P = 0.009).³³ Similarly, another retrospective review of 445 consecutive patients with malignant effusions revealed a pneumothorax rate of 0.97% using US in real time during needle insertion compared to 8.89% for unguided thoracenteses (P < 0.0001).³⁴ Several other studies using US guidance for either site markup or in real time reported similar pneumothorax rates, ranging from 1.1% - 4.8%.^35-37 However, it is unclear if real-time US specifically provides an additive effect vs site marking alone, as no studies directly comparing the 2 methods were found.

Benefits of US also include a higher rate of procedural success, with 1 study demonstrating a 99% success rate when using US vs. 90% without (P = 0.030).³³ A larger volume of fluid removed has been observed with US use as well, and methods have been described using fluid-pocket depth to guide puncture site localization and maximize drainage.³⁸ Finally, US use for thoracentesis has been associated with lower costs and length of stay.^39,40

Intercostal Artery Localization

Although rare (incidence, 0.18%-2%^20,21,39), the occurrence of hemothorax following thoracentesis is potentially catastrophic. This serious complication is often caused by laceration of the intercostal artery (ICA) or 1 of its branches during needle insertion.⁴¹

While risk of injury is theoretically reduced by needle insertion superior to the rib, studies using cadaver dissection and 3D angiography show significant tortuosity of the ICA.^6,41-43 The degree of tortuosity is increased within 6 cm of the midline, in more cephalad rib spaces, and in the elderly (older than 60 years).^41-43 Furthermore, 1 cadaveric study also demonstrated the presence of arterial collaterals branching off the ICA at multiple intercostal spaces, ranging between 8 cm and 11 cm from the midline.⁴¹ This anatomic variability may explain why some have observed low complication and hemothorax rates with an extreme lateral approach.³⁵ Bedside US with color flow Doppler imaging has been used to identify the ICA, with 88% sensitivity compared to CT imaging while adding little to exam time.^44,45 Of note, a 37% drop in the rate of hemothorax was observed in 1 study with routine US guidance alone.³⁹

Pleural Pressure Monitoring and Large-Volume Thoracentesis

While normal intrapleural pressures are approximately -5 to -10 cm H₂O,⁴⁶ the presence of a pleural effusion creates a complex interaction between fluid, compressed lung, and chest wall that can increase these pressures.⁴⁷ During drainage of an effusion, pleural pressures may rapidly drop, provoking re-expansion pulmonary edema (REPE). While rare (0 -1%), clinically-diagnosed REPE is a serious complication that can lead to rapid respiratory failure and death.^20,48 REPE is postulated to be caused by increased capillary permeability resulting from inflammation, driven by rapid re-inflation of the lung when exposed to highly negative intrapleural pressures.^47,49

Measurement of intrapleural pressure using a water manometer during thoracentesis may minimize REPE by terminating fluid drainage when intrapleural pressure begins to drop rapidly.^50,51 A cutoff of -20 cm H₂O has been cited repeatedly as safe since being suggested by Light in 1980, but this is based on animal models.^50,52 In 1 prospective study of 185 thoracenteses in which manometry was performed, 15% of patients had intrapleural pressure drop to less than -20 cm H₂O (at which point the procedure was terminated) but suffered no REPE.⁵⁰

Manometry is valuable in the identification of an unexpandable or trapped lung when pleural pressures drop rapidly with only minimal fluid volume removal.^47,53 Other findings correlated with an unexpandable lung include a negative opening pressure⁴⁷ and large fluctuations in pressure during the respiratory cycle.⁵⁴

While development of symptoms (eg, chest pain, cough, or dyspnea) is often used as a surrogate, the correlation between intrapleural pressure and patient symptoms is inconsistent and not a reliable proxy.⁵⁵ One study found that 22% of patients with chest pain during thoracentesis had intrapleural pressures lower than -20 cm H₂O compared with 8.6% of asymptomatic patients,⁵⁶ but it is unclear if the association is causal.

Thoracentesis is often performed for symptomatic relief and removal of large fluid volume. However, it remains common to halt fluid removal after 1.5 L, a threshold endorsed by BTS.¹⁹ While some investigators have suggested that removal of 2 L or more of pleural fluid does not compromise safety,^57,58 a 4- to 5-fold rise in the risk of pneumothorax was noted in 2 studies.^20,59 when more than 1.5 L of fluid was removed. The majority of these may be related to pneumothorax ex vacuo, a condition in which fluid is drained from the chest, but the lung is unable to expand and fill the space (eg, “trapped lung”), resulting in a persistent pneumothorax. This condition generally does not require treatment.⁶⁰ When manometry is employed at 200-mL intervals with termination at an intrapleural pressure of less than 20 mm H₂O, drainage of 3 L or more has been reported with low rates of pneumothorax and very low rates of REPE.^50,51 However, whether this is cause and effect is unknown because REPE is rare, and more work is needed to determine the role of manometry for its prevention.

POSTPROCEDURAL CONSIDERATIONS

Postprocedure Imaging

Performing an upright CXR following thoracentesis is a practice that remains routinely done by many practitioners to monitor for complications. Such imaging was also endorsed by the American Thoracic Society guidelines.⁶¹ However, more recent data question the utility of this practice. Multiple studies have confirmed that post-thoracentesis CXR is unnecessary unless clinical suspicion for pneumothorax or REPE is present.^36,58,62,63 The BTS guidelines also advocate this approach.¹⁹ Interestingly, a potentially more effective way to screen for postprocedure complications is through bedside US, which has been shown to be more sensitive than CXR in detecting pneumothorax.⁶⁴ In 1 study of 185 patients, bedside US demonstrated a sensitivity of 88% and a specificity of 97% for diagnosing pneumothorax in patients with adequate quality scans, with positive and negative likelihood ratios of 55 and 0.17, respectively.⁶⁵

Thoracentesis remains a core procedural skill for hospitalists, critical care physicians, and emergency physicians. It is the foundational component when investigating and treating pleural effusions. When the most current training, techniques, and technology are used, data suggest this procedure is safe to perform at the bedside. Our review highlights these strategies and evaluates which aspects might be most applicable to clinical practice.

Our findings have several implications for those who perform this procedure. First, appropriate training is central to procedural safety, and both simulation and direct observation by procedural experts have been shown by multiple investigators to improve knowledge and skill. This training should integrate the use of US in performing a focused thoracic exam.

Second, recommendations regarding coagulopathy and a “safe cutoff” of an INR less than 1.5 or platelets greater than 50,000/µL had limited evidentiary support. Rather, multiple studies suggest no difference in bleeding risk following thoracentesis with an INR as high as 3.0 and platelets greater than 25,000/µL. Furthermore, prophylactic transfusion with fresh frozen plasma or platelets before thoracentesis did not alter bleeding risk and exposes patients to transfusion complications. Thus, routine use of this practice can no longer be recommended. Third, further research is needed to understand the bleeding risk for patients on antiplatelet medications, heparin products, and also direct oral anticoagulants, given the growing popularity in their use and the potential consequences of even temporary cessation. Regarding patients on mechanical ventilation, thoracentesis demonstrated no difference in complication rates vs. the general population, and its performance in this population is encouraged when clinically indicated.

Intraprocedural considerations include the use of bedside US. Due to multiple benefits including effusion characterization, puncture site localization, and significantly lower rates of pneumothorax, the standard of care should be to perform thoracentesis with US guidance. Both use of US to mark an effusion immediately prior to puncture or in real time during needle insertion demonstrated benefit; however, it is unclear if 1 method is superior because no direct comparison studies were found. Further work is needed to investigate this potential.

Our review suggests that the location and course of the ICA is variable, especially near the midline, in the elderly, and in higher intercostal spaces, leaving it vulnerable to laceration. We recommend physicians only attempt thoracentesis at least 6 cm lateral to the midline due to ICA tortuosity and, ideally, 12 cm lateral, to avoid the presence of collaterals. Although only 2 small-scale studies were found pertaining to the use of US in identifying the ICA, we encourage physicians to consider learning how to screen for its presence as a part of their routine thoracic US exam in the area underlying the planned puncture site.

Manometry is beneficial because it can diagnose a nonexpandable lung and allows for pleural pressure monitoring.^52,53 A simple U-shaped manometer can be constructed from intravenous tubing included in most thoracentesis kits, which adds little to overall procedure time. While low rates of REPE have been observed when terminating thoracentesis if pressures drop below -20 cm H₂O or chest pain develops, neither measure appears to have reliable predictive value, limiting clinical utility. Further work is required to determine if a “safe pressure cutoff” exists. In general, we recommend the use of manometry when a nonexpandable (trapped) lung is suspected, because large drops in intrapleural pressure, a negative opening pressure, and respiratory variation can help confirm the diagnosis and avoid pneumothorax ex vacuo or unnecessary procedures in the future. As this condition appears to be more common in the setting of larger effusions, use of manometry when large-volume thoracenteses are planned is also reasonable.

Postprocedurally, routine imaging after thoracentesis is not recommended unless there is objective concern for complication. When indicated, bedside US is better positioned for this role compared with CXR, because it is more sensitive in detecting pneumothorax, provides instantaneous results, and avoids radiation exposure.

Our review has limitations. First, we searched only for articles between defined time periods, restricted our search to a single database, and excluded non-English articles. This has the potential to introduce selection bias, as nonprimary articles that fall within our time restrictions may cite older studies that are outside our search range. To minimize this effect, we performed a critical review of all included studies, especially nonprimary articles. Second, despite the focus of our search strategy to identify any articles related to patient safety and adverse events, we cannot guarantee that all relevant articles for any particular complication or risk factor were captured given the lack of more specific search terms. Third, although we performed a systematic search of the literature, we did not perform a formal systematic review or formally grade included studies. As the goal of our review was to categorize and operationalize clinical aspects, this approach was necessary, and we acknowledge that the quality of studies is variable. Lastly, we aimed to generate clinical recommendations for physicians performing thoracentesis at the bedside; others reviewing this literature may find or emphasize different aspects relevant to practice outside this setting.

In conclusion, evaluation and treatment of pleural effusions with bedside thoracentesis is an important skill for physicians of many disciplines. The evidence presented in this review will help inform the process and ensure patient safety. Physicians should consider incorporating these recommendations into their practice.

Acknowledgments

The authors thank Whitney Townsend, MLIS, health sciences informationist, for assistance with serial literature searches.

Disclosure

Nothing to report.