Clinical practice of early extubation after liver transplantation

Predictive Score for Early Successful Tracheal Extubation After Liver Transplant: A Case-Control Study

OBJECTIVES

Prolonged tracheal intubation and mechanical ventilation after liver transplant increase postoperative complications. Hence, timely extubation should be considered; however, a standard clinical criteria set or scoring system to select patients has not been established for early extubation after livertransplant.We investigated the factors that affect early extubation to design a predictive scoring system for early extubation.

MATERIALS AND METHODS

This study is a case-control study of adult liver transplant patients. Preoperative, intraoperative, and postoperative clinical data were collected. Early extubation was defined as tracheal extubation immediately or up to 6 hours posttransplant. The variables were compared between the early extubation group and the delayed extubation (>6 hours) group.

RESULTS

Our study enrolled 237 patients; among them, 57 patients (24%) were in the early extubation group, and 180 (76%) were in the delayed extubation group. Multiple logistic regression analysis showed that postoperative base excess level at admission to the intensive care unit, number of units of packed red blood cells transfused during surgery, urine volume, and excess base level 6 hours after surgery were the main predictors of successful early extubation.

CONCLUSIONS

The initial base excess level at the entrance to the intensive care unit(postsurgery) and 6 hours after surgery, packed red blood cell volume transfused during surgery, and urine volume 6 hours after surgery are the main predictors for a successful early tracheal extubation.These factors are considered for the Shiraz Extubation Predictor formula.

The Practice of Fast-Track Liver Transplant Anesthesia

Prior to the 1990s, prolonged postoperative intubation and admission to the intensive care unit was considered the standard of care following liver transplantation. Advocates of this practice speculated that this time allowed patients to recover from the stress of major surgery and allowed their clinicians to optimize the recipients' hemodynamics. As evidence in the cardiac surgical literature on the feasibility of early extubation grew, clinicians began applying these principles to liver transplant recipients. Further, some centers also began challenging the dogma that patients need to be cared for in the intensive care unit following liver transplantation and instead transferred patients to the floor or stepdown units immediately following surgery, a technique known as "fast-track" liver transplantation. This article aims to provide a history of early extubation for liver transplant recipients and offer practical advice on how to select patients that may be able to bypass the intensive care unit and be recovered in a non-traditional manner.

Comprehensive quality initiative leads to immediate postoperative extubation following liver transplant

BACKGROUND

Immediate postoperative extubation (IPE) can reduce perioperative complications and length of stay (LOS), however it is performed variably after liver transplant across institutions and has historically excluded high-risk recipients from consideration. In late 2012, we planned and implemented a single academic institution structured quality improvement (QI) initiative to standardize perioperative care of liver transplant recipients without exceptions. We hypothesized that such an approach would lead to a sustained increase in IPE after primary (PAC) and delayed abdominal closure (DAC).

METHODS

We retrospectively studied 591 patients from 2013 to 2018 who underwent liver transplant after initiative implementation. We evaluated trends in incidence of IPE versus delayed extubation (DE), and reintubation, LOS, and mortality.

RESULTS

Overall, 476/591 (80.5%) recipients underwent PAC (278 IPE, 198 DE) and 115/591 (19.5%) experienced DAC (39 IPE, 76 DE). When comparing data from 2013 to data from 2018, the incidence of IPE increased from 9/67 (13.4%) to 78/90 (86.7%) after PAC and from 1/12 (8.3%) to 16/23 (69.6%) after DAC. For the same years, the incidence of IPE after PAC for recipients with MELD scores ≥30 increased from 0/19 (0%) to 12/17 (70.6%), for recipients who underwent simultaneous liver-kidney transplant increased from 1/8 (12.5%) to 4/5 (80.0%), and for recipients who received massive transfusion (>10 units of packed red blood cells) increased from 0/17 (0%) to 10/13 (76.9%). Reintubation for respiratory considerations <48 h after IPE occurred in 3/278 (1.1%) after PAC and 1/39 (2.6%) after DAC. IPE was associated with decreased intensive care unit (HR of discharge: 1.92; 95% CI: 1.58, 2.33; P < 0.001) and hospital LOS (HR of discharge: 1.45; 95% CI: 1.20, 1.76; P < 0.001) but demonstrated no association with mortality.

CONCLUSION

A structured QI initiative led to sustained high rates of IPE and reduced LOS in all liver transplant recipients, including those classified as high risk.

Adult liver transplant anesthesiology practice patterns and resource utilization in the United States: Survey results from the society for the advancement of transplant anesthesia

INTRODUCTION

Liver transplant anesthesiology is an evolving and expanding subspecialty, and programs have, in the past, exhibited significant variations of practice at transplant centers across the United States. In order to explore current practice patterns, the Quality & Standards Committee from the Society for the Advancement of Transplant Anesthesia (SATA) undertook a survey of liver transplant anesthesiology program directors.

METHODS

Program directors were invited to participate in an online questionnaire. A total of 110 program directors were identified from the 2018 Scientific Registry of Transplant Recipients (SRTR) database. Replies were received from 65 programs (response rate of 59%).

RESULTS

Our results indicate an increase in transplant anesthesia fellowship training and advanced training in transesophageal echocardiography (TEE). We also find that the use of intraoperative TEE and viscoelastic testing is more common. However, there has been a reduction in the use of veno-venous bypass, routine placement of pulmonary artery catheters and the intraoperative use of anti-fibrinolytics when compared to prior surveys.

CONCLUSION

The results show considerable heterogeneity in practice patterns across the country that continues to evolve. However, there appears to be a movement towards the adoption of specific structural and clinical practices.

Immediate Postoperative Extubation Decreases Pulmonary Complications in Liver Transplant Patients

BACKGROUND

Fast-track anesthesia in liver transplantation (LT) has been discussed over the past few decades; however, factors associated with immediate extubation after LT surgery are not well defined. This study aimed to identify predictive factors and examine impacts of immediate extubation on post-LT outcomes.

METHODS

A total of 279 LT patients between January 2014 and May 2017 were included. Primary outcome was immediate extubation after LT. Other postoperative outcomes included reintubation, intensive care unit stay and cost, pulmonary complications within 90 days, and 90-day graft survival. Logistic regression was performed to identify factors that were predictive for immediate extubation. A matched control was used to study immediate extubation effect on the other postoperative outcomes.

RESULTS

Of these 279 patients, 80 (28.7%) underwent immediate extubation. Patients with anhepatic time >75 minutes and with total intraoperative blood transfusion ≥12 units were less likely to be immediately extubated (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.26-0.89; P = 0.02; OR, 0.11; 95% CI, 0.05-0.21; P < 0.001). The multivariable analysis showed immediate extubation significantly decreased the risk of pulmonary complications (OR, 0.34; 95% CI, 0.15-0.77; P = 0.01). According to a matched case-control model (immediate group [n = 72], delayed group [n = 72]), the immediate group had a significantly lower rate of pulmonary complications (11.1% versus 27.8%; P = 0.012). Intensive care unit stay and cost were relatively lower in the immediate group (2 versus 3 d; P = 0.082; $5700 versus $7710; P = 0.11). Reintubation rates (2.8% versus 2.8%; P > 0.9) and 90-day graft survival rates (95.8% versus 98.6%; P = 0.31) were similar.

CONCLUSIONS

Immediate extubation post-LT in appropriate patients is safe and may improve patient outcomes and resource allocation.

Enhanced recovery in liver transplantation: A value-based approach to complex surgical care

BACKGROUND

Value-based healthcare focuses on improving outcomes relative to cost. We aimed to study the impact of an enhanced recovery pathway for liver transplant recipients on providing value.

METHODS

In total, 379 liver recipients were identified: pre-enhanced recovery pathway (2017, n = 57) and post-enhanced recovery pathway (2018-2020, n = 322). The enhanced recovery pathway bundle was defined through multidisciplinary efforts and included optimal fluid management, end-of-case extubation, multimodal analgesia, and a standardized care pathway. Pre- and post-enhanced recovery pathway patients were compared with regard to extubation rates, lengths of stay, complications, readmissions, survival, and costs.

RESULTS

Pre- and post-enhanced recovery pathway recipient model for end-stage liver disease score and balance of risk scores were similar, although post-enhanced recovery pathway recipients had a higher median donor risk index (1.55 vs 1.39, P = .003). End-of-case extubation rates were 78% post-enhanced recovery pathway (including 91% in 2020) versus 5% pre-enhanced recovery pathway, with post-enhanced recovery pathway patients having decreased median intraoperative transfusion requirements (1,500 vs 3,000 mL, P < .001). Post-enhanced recovery pathway recipients had shorter median intensive care unit (1.6 vs 2.3 days, P = .01) and hospital stays (5.4 vs 8.0 days, P < .001). Incidence of severe (Clavien-Dindo ≥3) complications during the index hospitalization were similar between pre-enhanced recovery pathway versus post-enhanced recovery pathway groups (33% vs 23%, P = .13), as were 30-day readmissions (26% vs 33%, P = .44) and 1-year survival (93.0% vs 94.5%, P = .58). The post-enhanced recovery pathway cohort demonstrated a significant reduction in median direct cost per case ($11,406; P < .001).

CONCLUSION

Implementation of an enhanced recovery pathway in liver transplantation is feasible, safe, and effective in delivering value, even in the setting of complex surgical care.

Predictors of success of immediate tracheal extubation in living donor liver transplantation recipients

Background

Early tracheal extubation of recipients following liver transplantation (LT) has been gradually replacing the standard postoperative prolonged mechanical ventilation, contributing to better patient and graft survival and reduced costs. There are no universally accepted predictors of the success of immediate extubation in LT recipients. We hypothesized several potential predictors of successful immediate tracheal extubation in living donor liver transplantation (LDLT) recipients.

Aim

Evaluation of the validity of the following hypothesized factors: model for end-stage liver disease (MELD) score, duration of surgery, number of intraoperatively transfused packed red blood cells (RBCs) units, and end of surgery (EOS) serum lactate, as predictors of success of immediate tracheal extubation in living donor liver transplantation (LDLT) recipients.

Methods

In this prospective clinical investigation, perioperative data of adult living donor liver transplantation (LDLT) recipients were recorded. “Immediate extubation” was defined as tracheal extubation immediately and up to 1 hour post-transplant in the operating room. Patients were divided into the extubated group who were successfully extubated with no need for reintubation, and the non-extubated group who failed to meet the criteria of extubation, or were re-intubated within 4 hours of extubation.

Results

We enrolled 64 patients candidates for LDLT; 50 patients (76.9%) in group 1 were extubated early after LDLT while 14 patients (23.07%) in group 2 were transferred to the intensive care unit intubated. After data analysis, we found that EOS serum lactate, duration of surgery and number of packed RBCs units transfused intraoperatively were good predictors of success of immediate extubation (p < 0.001). MELD scores did not show any significant impact on the results (p = 0.54). Other factors such as EOS urine output and blood gases indices were shown to have a significant effect on the decision of extubation (p = 0.03 and 0.006, respectively).

Conclusions

EOS serum lactate, duration of surgery and number of packed RBCs units transfused were potential predictors of post-transplant early extubation.

Association Between Fast-Track Extubation After Orthotopic Liver Transplant, Postoperative Vasopressor Requirement, and Acute Kidney Injury

OBJECTIVES

Acute kidney injury is a significant cause of morbidity after orthotopic liver transplant. Early extubation after liver transplant may have a beneficial effect on postoperative renal function. This may be the result of reduction in vasopressor-mediated vasoconstriction used to counteract the hypotension associated with sedative use and the effects of positive-pressure ventilation. Previous studies explored advantages of early extubation after liver transplant but focused on resource usage rather than clinical benefit. This study was designed to determine the association between fast-track extubation and reduction in postoperative vasopressor requirement and whether this had any association with acute kidney injury incidence or renal replacement therapy requirement.

MATERIALS AND METHODS

Data were collected from 144 orthotopic liver transplants. A propensity-matched case-control analysis was conducted on a subgroup of 33 patients who were fast-track extubated and with 33 propensity score-matched control patients who were not. The primary outcome was median days of postoperative vasopressor use, and secondary outcomes included incidence of acute kidney injury, renal replacement therapy requirement, and critical care admission duration.

RESULTS

The fast-track extubation group had a shorter postoperative vasopressor requirement (0 vs 2 days; P < .01) and a reduced need for renal replacement therapy (3% vs 21.2%; P = .05). Median critical care admission duration (3 vs 4 days; P = .03) and hospital admission duration (14 vs 19 days; P = .04) were shorter in the fast-track extubation group.

CONCLUSIONS

This is the first study to reveal a significant association between fast-track extubation and reduced postoperative vasopressor requirement. Additionally, this was associated with a trend toward reduced renal replacement requirement after liver transplant. It suggests that early extubation may not just be a resource benefit to an institution but may convey a clinical benefit to patients through a reduction in organ failure and requirement for organ support.

Fast-Track Liver Transplantation: Six-year Prospective Cohort Study with an Enhanced Recovery After Surgery (ERAS) Protocol

Introduction

Enhanced recovery after surgery (ERAS) has been shown to facilitate discharge, decrease length of stay, improve outcomes and reduce costs. We used this concept to design a comprehensive fast-track pathway (OR-to-discharge) before starting our liver transplant activity and then applied this protocol prospectively to every patient undergoing liver transplantation at our institution, monitoring the results periodically. We now report our first six years results.

Patients and methods

Prospective cohort study of all the liver transplants performed at our institution for the first six years. Balanced general anesthesia, fluid restriction, thromboelastometry, inferior vena cava preservation and temporary portocaval shunt were strategies common to all cases. Standard immunosuppression administered included steroids, tacrolimus (delayed in the setting of renal impairment, with basiliximab induction added) and mycophenolate mofetil. Tacrolimus dosing was adjusted using a Bayesian estimation methodology. Oral intake and ambulation were started early.

Results

A total of 240 transplants were performed in 236 patients (191♂/45♀) over 74 months, mean age 56.3±9.6 years, raw MELD score 15.5±7.7. Predominant etiologies were alcohol (n = 136) and HCV (n = 82), with hepatocellular carcinoma present in 129 (54.7%). Nine patients received combined liver and kidney transplants. The mean operating time was 315±64 min with cold ischemia times of 279±88 min. Thirty-one patients (13.1%) were transfused in the OR (2.4±1.2 units of PRBC). Extubation was immediate (< 30 min) in all but four patients. Median ICU length of stay was 12.7 hours, and median post-transplant hospital stay was 4 days (2-76) with 30 patients (13.8%) going home by day 2, 87 (39.9%) by day 3, and 133 (61%) by day 4, defining our fast-track group. Thirty-day-readmission rate (34.9%) was significantly lower (28.6% vs. 44.7% p=0.015) in the fast-track group. Patient survival was 86.8% at 1 year and 78.6% at five years.

Conclusion

Fast-Tracking of Liver Transplant patients is feasible and can be applied as the standard of care

Predictive score for immediate extubation after liver transplantation

INTRODUCTION

Evidence suggests that immediate extubation after liver transplantation provides graft and economic benefits without compromising patient outcomes. This study tried to determine the incidence of immediate extubation, demonstrate related factors, and develop a predictive model from the significant factors.

METHODS

This retrospective descriptive study included 240 out of 271 liver transplantation patients in the hospital liver transplant registry between 2004 and 2016. Extubated and non-extubated groups were statistically compared.

RESULTS

The incidence of immediate extubation was 32.1%. It was associated with a MELD score ≤ 25 (adjusted OR, 5.17; 95% CI, 1.64-16.24; p = .005); packed red cells (PRC) transfusion ≤1600 ml (adjusted OR, 3.45; 95% CI, 1.82-6.53; p < .001); and no requirement for post-operative vasopressors (adjusted OR, 5.83; 95% CI, 2.30-14.77; p < .001). The immediate-extubation group had fewer complications and shorter hospital stays. A Siriraj Liver transplant Extubation Score (SLES) of 5 yielded the best prediction of safe immediate extubation.

CONCLUSIONS

An incidence of 32.1% was found for immediate extubation following liver transplantation. Associated factors were a MELD score ≤ 25, a lower amount of transfused blood, and no requirement for post-operative vasopressors. An SLES score of 5 predicted safe immediate extubation.

Immediate versus conventional postoperative tracheal extubation for enhanced recovery after liver transplantation: IPTE versus CTE for enhanced recovery after liver transplantation

INTRODUCTION

To systematically compare immediate postoperative tracheal extubation (IPTE) with conventional tracheal extubation (CTE) and to determine whether IPTE can achieve an enhanced recovery for adult patients underwent liver transplantation (LT) without additional risks. We designed a systematic review and meta-analysis.

METHODS

The RCTs, cohorts, case-controls, or case series that explored outcomes of IPTE after LT for adults were involved in our study. The Newcastle-Ottawa scale was used to assess the risk of bias.

RESULTS

A total of 15 studies (n = 4144) were included, consisting of 10 studies (retrospective cohorts; n = 3387) for quantitative synthesis and 5 studies (1 prospective cohort, and 4 case series; n = 757) for qualitative synthesis. The pooled estimates suggested IPTE could reduce time to discharge from ICU stay (TDICU) (mean difference [MD] -2.12 days, 95% confidence interval [CI] -3.04 to -1.19 days), time to discharge from the hospital (TDH) (MD -6.43 days, 95% CI -9.53 to -3.33 days), re-intubation rate (RI) (odds ratio [OR] 0.29, 95% CI 0.22-0.39), morbidity rate (MR) (OR 0.15, 95% CI 0.08-0.30) and graft dysfunction rate (GD) (IPTE vs CTE: 0.3% vs 3.8%, P < .01), and had comparable ICU survival rate (ICUS) (OR 6.67 95% CI 1.34-33.35) when compared with CTE after LT.

CONCLUSIONS

IPTE can achieve an enhanced recovery for adult patients underwent LT without additional re-intubation, morbidity, and mortality risks. However, further work needs to be done to establish the extent definitively through carefully designed and conducted RCTs.

Early Bacterial Pneumonia After Hepatic Transplantation: Epidemiologic Profile

BACKGROUND

Postoperative pulmonary complications are major cause of morbidity and mortality in patients receiving liver transplantation (LT), particularly bacterial pneumonia occurring within the first 100 days after transplantation. Our aim in this study was to determine the incidence, microorganisms involved, associated factors, and morbidity of bacterial pneumonia presenting in the first 100 days posttransplant.

METHODS

We performed a cohort study in which patients receiving liver transplantation were included prospectively in our national database (Database of Infections in Transplantation of Solid Organs). The study period was from July 14, 2009 to July 24, 2015.

RESULTS

One hundred six patients were transplanted during the 6-year period. We documented 9 bacterial pneumonia cases with an incidence of 8.5 per 100 patients; 2 patients had hospital-acquired pneumonia (HAP) and 7 had ventilator-associated pneumonia (VAP). In 4 of the 9 bacterial pneumonia cases, patients presented with bacteremia. Eleven microorganisms were isolated these 9 patients. Microbiologic diagnosis methods included 5 cases of alveolar bronchoalveolar lavage (BAL), 1 case of BAL and pleural fluid puncture, 1 case of pleural fluid puncture, and 1 case through sputum study. Of the 11 isolated organisms, 9 corresponded to Gram-negative bacilli (GNB): Klebsiella spp, n = 3; Acinetobacter baumannii, n = 4; Morganella morganii, n = 1; and Pseudomonas aeruginosa, n = 1. Regarding the resistance profile, 7 presented with a multiresistance profile (MDR) and extreme resistance (XDR). Univariate analysis identified the Model for End-Stage Liver Disease (MELD) pretransplant score as a factor associated with developing pneumonia (P < .001, 95% confidence interval [CI] 2.872-10.167), and early extubation, before 8 hours posttransplant, as a protective factor (P = .008; relative risk [RR] 0.124; 95% CI 0 .041-0.377). Hospital stay was longer in patients with pneumonia compared to those without pneumonia (P < .0001, 95% CI 17.79-43.11 days). There was also an increased risk of death in patients with pneumonia (RR 17.963; 95% CI 5106-63,195).

CONCLUSIONS

Early bacterial pneumonia after hepatic transplantation is associated with higher morbidity and mortality. At our center, 4 of 9 patients had bacteremia. GNB cases with MDR and XDR profiles are predominant. Early extubation is a protective factor.

Analgesia after liver transplantation

This article addresses postoperative analgesia in patients with end-stage liver disease who have undergone liver transplantation (LT). Postoperative analgesia determines how patients perceive LT. Although important, this topic is underrepresented in the current literature. With an increased frequency of fast tracking in LT, efficient intra- and postoperative analgesia are undergoing changes. We herein review the current literature, compare the benefits and disadvantages of the therapeutic options, and make recommendations based on the current literature and clinical experience.

Intraoperative predictors of early tracheal extubation after living-donor liver transplantation

BACKGROUND

Prolonged mechanical ventilation after liver transplantation has been associated with deleterious clinical outcomes, so early tracheal extubation posttransplant is now increasing. However, there is no universal clinical criterion for predicting early extubation in living-donor liver transplantation (LDLT). We investigated specific predictors of early extubation after LDLT.

METHODS

Perioperative data of adult patients undergoing LDLT were reviewed. "Early" extubation was defined as tracheal extubation in the operating room or intensive care unit (ICU) within 1 h posttransplant, and we divided patients into early extubation (EX) and non-EX groups. Potentially significant (P < 0.10) perioperative variables from univariate analyses were entered into multivariate logistic regression analyses. Individual cut-offs of the predictors were calculated by area under the receiver operating characteristic curve (AUC) analysis.

RESULTS

Of 107 patients, 66 (61.7%) were extubated early after LDLT. Patients in the EX group showed shorter stays in the hospital and ICU and lower incidences of reoperation, infection, and vascular thrombosis. Preoperatively, model for end-stage liver disease score, lung disease, hepatic encephalopathy, ascites, and intraoperatively, surgical time, transfusion of packed red blood cell (PRBC), urine output, vasopressors, and last measured serum lactate were associated with early extubation (P < 0.05). After multivariate analysis, only PRBC transfusion of ≤ 7.0 units and last serum lactate of ≤ 8.2 mmol/L were selected as predictors of early extubation after LDLT (AUC 0.865).

CONCLUSIONS

Intraoperative serum lactate and blood transfusion were predictors of posttransplant early extubation. Aggressive efforts to ameliorate intraoperative circulatory issues would facilitate successful early extubation after LDLT.