Acute kidney injury in patients with cirrhosis: Acute Disease Quality Initiative (ADQI) and International Club of Ascites (ICA) joint multidisciplinary consensus meeting.

Patients with cirrhosis are prone to developing acute kidney injury (AKI), a complication associated with a markedly increased in-hospital morbidity and mortality, along with a risk of progression to chronic kidney disease. Whereas patients with cirrhosis are at increased risk of developing any phenotype of AKI, hepatorenal syndrome (HRS), a specific form of AKI (HRS-AKI) in patients with advanced cirrhosis and ascites, carries an especially high mortality risk. Early recognition of HRS-AKI is crucial since administration of splanchnic vasoconstrictors may reverse the AKI and serve as a bridge to liver transplantation, the only curative option. In 2023, a joint meeting of the International Club of Ascites (ICA) and the Acute Disease Quality Initiative (ADQI) was convened to develop new diagnostic criteria for HRS-AKI, to provide graded recommendations for the work-up, management and post-discharge follow-up of patients with cirrhosis and AKI, and to highlight priorities for further research.

Serum lactate and mean arterial pressure thresholds in patients with cirrhosis and septic shock.

BACKGROUND: The Sepsis-3 guidelines have incorporated serum lactate levels of >2 mmol/L in septic shock definition to account for higher observed mortality. Further evidence is needed to support this threshold in cirrhosis, as well as target mean arterial pressure (MAP) during resuscitation. METHODS: This observational cohort study investigated the association between initial serum lactate and resuscitation MAP levels on in-hospital mortality in patients with and without cirrhosis. Patients admitted to the intensive care unit for the treatment of septic shock between 2006 and 2021 in a quaternary academic center were included. Patients with cirrhosis documented on imaging and International Classification of Disease codes (n=595) were compared to patients without cirrhosis (n=575). The association of intensive care unit admission lactate levels and median 2-hour MAP with in-hospital mortality and the need for continuous renal replacement therapy was assessed. The association between median 24-hour MAP and in-hospital mortality was analyzed post hoc. RESULTS: Within the cirrhosis group, admission lactate levels of 2-4 and >4 mmol/L were associated with increased in-hospital mortality compared to lactate <2 mmol/L [adjusted odds ratio (aOR): 1.69, CI: 1.03-2.81, aOR: 4.02, CI: 2.53-6.52]. Median 24-hour MAP 60-65 and <60 mm Hg were also associated with increased in-hospital mortality compared with MAP >65 mm Hg (aOR: 2.84, CI: 1.64-4.92 and aOR: 7.34, CI: 3.17-18.76). In the noncirrhosis group, associations with in-hospital mortality were weaker for lactate 2-4 and >4 mmol/L (aOR: 1.32, CI: 0.77-2.27 and aOR: 2.25, CI: 1.40-3.67) and median 24-hour MAP 60-65 and <60 mm Hg (aOR: 1.70, CI: 0.65-4.14 and aOR: 4.41, CI: 0.79-29.38). CONCLUSIONS: These findings support utilizing lactate >2 mmol/L in the definition of septic shock, as well as a target MAP of >65 mm Hg during resuscitation in patients with cirrhosis.

Comparative efficacy of terlipressin and norepinephrine for treatment of hepatorenal syndrome-acute kidney injury: A systematic review and meta-analysis.

The treatment of choice for hepatorenal syndrome-acute kidney injury (HRS-AKI) is vasoconstrictor therapy in combination with albumin, preferably norepinephrine or terlipressin as recommended by recent guidelines. In the absence of larger head-to-head trials comparing the efficacy of terlipressin and norepinephrine, meta-analysis of smaller studies can provide insights needed to understand the comparative effects of these medications. Additionally, recent changes in the HRS diagnosis and treatment guidelines underscore the need for newer analyses comparing terlipressin and norepinephrine. In this systematic review, we aimed to assess reversal of hepatorenal syndrome (HRS) and 1-month mortality in subjects receiving terlipressin or norepinephrine for the management of HRS-AKI. We searched literature databases, including PubMed, Cochrane, Clinicaltrials.gov, International Clinical Trials Registry Platform, Embase, and ResearchGate, for randomized controlled trials (RCTs) published from January 2007 to June 2023 on June 26, 2023. Only trials comparing norepinephrine and albumin with terlipressin and albumin for the treatment of HRS-AKI in adults were included, and trials without HRS reversal as an endpoint or nonresponders were excluded. Pairwise meta-analyses with the random effects model were conducted to estimate odds ratios (ORs) for HRS reversal and 1-month mortality as primary outcomes. Additional outcomes assessed, included HRS recurrence, predictors of response, and incidence of adverse events (AEs). We used the Cochrane risk of bias assessment tool for quality assessment. We included 7 RCTs with a total of 376 subjects with HRS-AKI or HRS type 1. This meta-analysis showed numerically higher rates of HRS reversal (OR 1.33, 95% confidence interval [CI] [0.80-2.22]; P = 0.22) and short-term survival (OR 1.50, 95% CI [0.64-3.53]; P = 0.26) with terlipressin, though these results did not reach statistical significance. Terlipressin was associated with AEs such as abdominal pain and diarrhea, whereas norepinephrine was associated with cardiovascular AEs such as chest pain and ischemia. Most of the AEs were reversible with a reduction in dose or discontinuation of therapy across both arms. Of the terlipressin-treated subjects, 5.3% discontinued therapy due to serious AEs compared to 2.7% of the norepinephrine-treated subjects. Limitations of this analysis included small sample size and study differences in HRS-AKI diagnostic criteria. As more studies using the new HRS-AKI criteria comparing terlipressin and norepinephrine are completed, a clearer understanding of the comparability of these 2 therapies will emerge.

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations

To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU. The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development. In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements. We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence. Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

Role of Terlipressin in Patients With Hepatorenal Syndrome-Acute Kidney Injury Admitted to the ICU: A Substudy of the CONFIRM Trial.

This study assessed the potential advantages of treating hepatorenal syndrome-acute kidney injury (HRS-AKI) with terlipressin versus placebo in the ICU setting. DESIGN: Patients were randomly assigned in a 2:1 ratio to receive terlipressin or placebo for up to 14 days. SETTING: A retrospective analysis of data from the phase III CONFIRM study. PARTICIPANTS: Adult patients with HRS-AKI admitted to the ICU. MAIN OUTCOMES AND MEASURES: In this substudy, we evaluated outcomes of the ICU stay and the need for organ support, including renal replacement therapy (RRT). RESULTS: Among 300 patients with HRS-AKI from the CONFIRM study, 45 were treated in the ICU (terlipressin, 31/199 [16%]; placebo, 14/101 [14%]). On ICU admission, baseline demographics were similar across treatment arms, including severity of liver dysfunction. Among patients alive at the end of the ICU stay, those randomized to terlipressin had a significantly shorter median length of ICU stay than placebo (4 vs 11 d; p < 0.001). Terlipressin-treated patients had a significantly larger improvement in renal function from baseline versus placebo (-0.7 vs +0.2 mg/dL; p = 0.001), including when accounting for the interaction between treatment and day-of-patient-admission to the ICU (-0.7 vs +0.9 mg/dL; p < 0.001). Cumulative requirement for RRT through day 90 was improved in the terlipressin arm versus placebo (10/31 [32%] vs 8/14 [57%]; p = 0.12), although not significantly. Of 13 patients who received a liver transplant, five out of five (100%) in the placebo arm needed RRT through day 90 versus five out of eight (63%) in the terlipressin arm. CONCLUSIONS: In this subanalysis of CONFIRM, patients admitted to the ICU with HRS-AKI who received terlipressin were more likely to achieve renal function improvement, based on serum creatinine changes by the end of treatment, and had significantly shorter lengths of ICU stay than patients randomized to the placebo arm.

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations.

OBJECTIVES: To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU. DESIGN: The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development. INTERVENTIONS: In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements. MEASUREMENTS AND MAIN RESULTS: We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence. CONCLUSIONS: Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

Intensive care management of liver transplant recipients.

PURPOSE OF REVIEW: Liver transplantation remains the only definitive treatment for advanced liver disease and liver failure. Current allocation schemes utilized for liver transplantation mandate a 'sickest first' approach, thus most liver transplants occur in patients with severe systemic illness. For intensive care providers who care for liver transplant recipients, a foundation of knowledge of technical considerations of orthotopic liver transplantation, basic management considerations, and common complications is essential. This review highlights the authors' approach to intensive care management of the postoperative liver transplant recipient with a review of common issues, which arise in this patient population. RECENT FINDINGS: The number of centers offering liver transplantation continues to increase globally and the number of patients receiving liver transplantation also continues to increase. The number of patients with advanced liver disease far outpaces organ availability and, therefore, patients undergoing liver transplant are sicker at the time of transplant. Outcomes for liver transplant patients continue to improve owing to advancements in surgical technique, immunosuppression management, and intensive care management of liver disease both pretransplant and posttransplant. SUMMARY: Given a global increase in liver transplantation, an increasing number of intensive care professionals are likely to care for this patient population. For these providers, a foundational knowledge of the common complications and key management considerations is essential.

Respiratory events with terlipressin and albumin in hepatorenal syndrome: A review and clinical guidance.

Hepatorenal syndrome-acute kidney injury (HRS-AKI) is a serious complication of severe liver disease with a clinically poor prognosis. Supportive care using vasoconstrictors and intravenous albumin are the current mainstays of therapy. Terlipressin is an efficacious vasoconstrictor that has been used for 2 decades as the first-line treatment for HRS-AKI in Europe and has demonstrated greater efficacy in improving renal function compared to placebo and other vasoconstrictors. One of the challenges associated with terlipressin use is monitoring and mitigating serious adverse events, specifically adverse respiratory events, which were noted in a subset of patients in the recently published CONFIRM trial, the largest randomized trial examining terlipressin use for HRS-AKI. In this article, we review terlipressin's pharmacology, hypothesize how its mechanism contributes to the risk of respiratory compromise and propose strategies that will decrease the frequency of these events by rationally selecting patients at lower risk for these events.

Persistent But Not Transient Acute Kidney Injury Was Associated With Lower Transplant-Free Survival in Patients With Acute Liver Failure: A Multicenter Cohort Study.

OBJECTIVES: Acute liver failure (ALF) is an orphan disease often complicated by acute kidney injury (AKI). We assessed the impact of transient versus persistent AKI on survival in patients with ALF. DESIGN: International multicenter retrospective cohort. SETTING: U.S. ALF Study Group prospective registry. PATIENTS: Patients with greater than or equal to 18 years and ALF in the registry from 1998 to 2016 were included. Patients with less than 3 days of follow-up, without kidney function evaluation on day 3, or with cirrhosis were excluded. INTERVENTIONS: AKI was defined by Kidney Disease Improving Global Outcomes guidelines on day 1. Kidney recovery was defined on day 3 as transient AKI, by a return to no-AKI within 48 hours or persistent AKI if no such recovery or renal replacement therapy (RRT) was observed. Primary outcome was transplant-free survival (TFS) at 21 days. MEASUREMENTS AND MAIN RESULTS: Among 1,071 patients with ALF, 339 (31.7%) were males, and median (interquartile range) age was 39 years (29-51 yr). Acetaminophen-related ALF was found in 497 patients (46.4%). On day 1, 485 of 1,071 patients (45.3%) had grade 3-4 hepatic encephalopathy (HE), 500 of 1,070 (46.7%) required invasive mechanical ventilation (IMV), 197 of 1,070 (18.4%) were on vasopressors, and 221 of 1,071 (20.6%) received RRT. On day 1, 673 of 1,071 patients (62.8%) had AKI. On day 3, 72 of 1,071 patients (6.7%) had transient AKI, 601 of 1,071 (56.1%) had persistent AKI, 71 of 1,071 (6.6%) had late onset AKI, and 327 of 1,071 (30.5%) remained without AKI. Following adjustment for confounders (age, sex, race, etiology, HE grade, use of IMV and vasopressors, international normalized ratio, and year), although persistent acute kidney injury (adjusted odds ratio [aOR] [95% CI] 0.62 [0.44-0.88]) or late onset AKI (aOR [95% CI] 0.48 [0.26-0.89]) was associated with lower TFS, transient AKI was not (aOR [95% CI] 1.89 [0.99-3.64]). CONCLUSIONS: In a multicenter cohort of patients with ALF, persistent but not transient AKI was independently associated with lower short-term TFS.

Immunosuppressive drugs and associated complications in abdominal organ transplantation.

PURPOSE OF REVIEW: Intensive care management of patients who have undergone organ transplantation of liver, small bowel, pancreas, and/or kidney requires a basic knowledge of immunosuppression principles and the management of immunosuppressive medications. This review highlights the core principles of immunosuppression management in abdominal organ transplantation with a focus on complications arising from immunosuppressive drugs, both in the immediate postoperative period and in long-term usage. RECENT FINDINGS: The general principles of management of immunosuppression in the abdominal organ transplant population have remained largely unchanged. Improvements in drug monitoring coupled with improvements in knowledge of pathways involved in allograft rejection have further refined immunosuppressive therapy. Infectious and central nervous system complications remain prevalent and are common complications of immunosuppressive drug therapy. SUMMARY: For the intensive care professional who cares for abdominal organ transplant recipients, a foundational knowledge of the core principles of immunosuppression management is essential. In addition, an understanding of the common immunosuppressive drug regimens and the complications associated with these regimens is required for optimal management, risk assessment, and outcomes.

Use of the Molecular Adsorbent Recirculating System in Acute Liver Failure: Results of a Multicenter Propensity Score-Matched Study.

OBJECTIVES: The molecular adsorbent recirculating system removes water-soluble and albumin-bound toxins and may be beneficial for acute liver failure patients. We compared the rates of 21-day transplant-free survival in acute liver failure patients receiving molecular adsorbent recirculating system therapy and patients receiving standard medical therapy. DESIGN: Propensity score-matched retrospective cohort analysis. SETTING: Tertiary North American liver transplant centers. PATIENTS: Acute liver failure patients receiving molecular adsorbent recirculating system at three transplantation centers (n = 104; January 2009-2019) and controls from the U.S. Acute Liver Failure Study Group registry. INTERVENTIONS: Molecular adsorbent recirculating system treatment versus standard medical therapy (control). MEASUREMENTS AND MAIN RESULTS: One-hundred four molecular adsorbent recirculating system patients were propensity score-matched (4:1) to 416 controls. Using multivariable conditional logistic regression adjusting for acute liver failure etiology (acetaminophen: n = 248; vs nonacetaminophen: n = 272), age, vasopressor support, international normalized ratio, King's College Criteria, and propensity score (main model), molecular adsorbent recirculating system was significantly associated with increased 21-day transplant-free survival (odds ratio, 1.90; 95% CI, 1.07-3.39; p = 0.030). This association remained significant in several sensitivity analyses, including adjustment for acute liver failure etiology and propensity score alone ("model 2"; molecular adsorbent recirculating system odds ratio, 1.86; 95% CI, 1.05-3.31; p = 0.033), and further adjustment of the "main model" for mechanical ventilation, and grade 3/4 hepatic encephalopathy ("model 3"; molecular adsorbent recirculating system odds ratio, 1.91; 95% CI, 1.07-3.41; p = 0.029). In acetaminophen-acute liver failure (n = 51), molecular adsorbent recirculating system was associated with significant improvements (post vs pre) in mean arterial pressure (92.0 vs 78.0 mm Hg), creatinine (77.0 vs 128.2 µmol/L), lactate (2.3 vs 4.3 mmol/L), and ammonia (98.0 vs 136.0 µmol/L; p ≤ 0.002 for all). In nonacetaminophen acute liver failure (n = 53), molecular adsorbent recirculating system was associated with significant improvements in bilirubin (205.2 vs 251.4 µmol/L), creatinine (83.1 vs 133.5 µmol/L), and ammonia (111.5 vs 140.0 µmol/L; p ≤ 0.022 for all). CONCLUSIONS: Treatment with molecular adsorbent recirculating system is associated with increased 21-day transplant-free survival in acute liver failure and improves biochemical variables and hemodynamics, particularly in acetaminophen-acute liver failure.

When Is a Critically Ill Cirrhotic Patient Too Sick to Transplant? Development of Consensus Criteria by a Multidisciplinary Panel of 35 International Experts.

BACKGROUND: Critically ill cirrhotic patients are increasingly transplanted, but there is no consensus about futile liver transplantation (LT). Therefore, the decision to delay or deny LT is often extensively debated. These debates arise from different opinions of futility among transplant team members. This study aims to achieve a multinational and multidisciplinary consensus on the definition of futility in LT and to develop well-articulated criteria for not proceeding with LT due to futility. METHODS: Thirty-five international experts from anesthesiology/intensive care, hepatology, and transplant surgery were surveyed using the Delphi method. More than 70% of similar answers to a question were necessary to define agreement. RESULTS: The panel recommended patient and graft survival at 1 year after LT to define futility. Severe frailty and persistent fever or <72 hours of appropriate antimicrobial therapy in case of ongoing sepsis were considered reasons to delay LT. A simple assessment of the number of organs failing was considered the most appropriate way to decide whether LT should be delayed or denied, with respiratory, circulatory and metabolic failures having the most influence in this decision. The thresholds of severity of organ failures contraindicating LT for which a consensus was achieved were a Pao2/FiO2 ratio<150 mm Hg, a norepinephrine dose >1 µg/kg per minute and a serum lactate level >9 mmol/L. CONCLUSIONS: Our expert panel provides a consensus on the definition of futile LT and on specific criteria for postponing or denying LT. A framework that may facilitate the decision if a patient is too sick for transplant is presented.

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Cardiovascular, Endocrine, Hematologic, Pulmonary, and Renal Considerations.

OBJECTIVES: To develop evidence-based recommendations for clinicians caring for adults with acute or acute on chronic liver failure in the ICU. DESIGN: The guideline panel comprised 29 members with expertise in aspects of care of the critically ill patient with liver failure and/or methodology. The Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy were followed throughout. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development. SETTING: The panel was divided into nine subgroups: cardiovascular, hematology, pulmonary, renal, endocrine and nutrition, gastrointestinal, infection, perioperative, and neurology. INTERVENTIONS: We developed and selected population, intervention, comparison, and outcomes questions according to importance to patients and practicing clinicians. For each population, intervention, comparison, and outcomes question, we conducted a systematic review aiming to identify the best available evidence, statistically summarized the evidence whenever applicable, and assessed the quality of evidence using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements. MEASUREMENTS AND MAIN RESULTS: In this article, we report 29 recommendations (from 30 population, intervention, comparison, and outcomes questions) on the management acute or acute on chronic liver failure in the ICU, related to five groups (cardiovascular, hematology, pulmonary, renal, and endocrine). Overall, six were strong recommendations, 19 were conditional recommendations, four were best-practice statements, and in two instances, the panel did not issue a recommendation due to insufficient evidence. CONCLUSIONS: Multidisciplinary international experts were able to formulate evidence-based recommendations for the management acute or acute on chronic liver failure in the ICU, acknowledging that most recommendations were based on low-quality indirect evidence.

The gastrointestinal system in the critically ill cirrhotic patient.

PURPOSE OF REVIEW: ICU admissions due to complications of advanced liver disease continue to rise. Among indications for admission to the ICU in patients with cirrhosis, gastrointestinal issues such as bleeding are common. In patients in whom gastrointestinal issues are not the principal indication for ICU, gastrointestinal issues such as nutrition and ileus remain important concerns for generalized intensive care support. This review highlights current trends in management of gastrointestinal issues in patients with cirrhosis admitted to the ICU. RECENT FINDINGS: General management of upper gastrointestinal bleeding remains largely unchanged. Improvements in interventional techniques have increased the options for difficult to control bleeding, these include the development of expandable esophageal stents and expanded experience with advanced interventional radiology techniques for the management of bleeding gastric varices. Frailty as an important prognostic marker in advanced liver disease and liver transplantation is the subject of several new studies and serves to highlight the importance of nutrition in the management of the critically ill cirrhotic patient. SUMMARY: Gastrointestinal complications are frequent in the critically ill cirrhotic patient. Recognition and intervention in a timely manner may minimize morbidity and mortality and result in improved outcomes for this vulnerable population.

A 360° Rotational Positioning Protocol of Organ Donors May Increase Lungs Available for Transplantation.

OBJECTIVES: To evaluate the improvement in lung donation and immediate lung function after the implementation of a 360° rotational positioning protocol within an organ procurement organization in the Midwest. DESIGN: Retrospective observational study. SETTING: The Midwest Transplant Network from 2005 to 2017. Rotational positioning of donors began in 2008. SUBJECTS: Potential deceased lung donors. INTERVENTIONS: A 360° rotational protocol. Presence of immediate lung function in recipients, change in PaO2:FIO2 ratio during donor management, initial and final PaO2:FIO2 ratio, and proportion of lungs donated were measured. Outcomes were compared between rotated and nonrotated donors. MEASUREMENTS AND MAIN RESULTS: A total of 693 donors were analyzed. The proportion of lung donations increased by 10%. The difference between initial PaO2:FIO2 ratio and final PaO2:FIO2 ratio was significantly different between rotated and nonrotated donors (36 ± 116 vs 104 ± 148; p < 0.001). Lungs transplanted from rotated donors had better immediate function than those from nonrotated donors (99.5% vs 68%; p < 0.001). CONCLUSIONS: There was a statistically significant increase in lung donations after implementing rotational positioning of deceased donors. Rotational positioning significantly increased the average difference in PaO2:FIO2 ratios. There was also superior lung function in the rotated group. The authors recommend that organ procurement organizations consider adopting a rotational positioning protocol for donors to increase the lungs available for transplantation.