Increased Incidence of Transfusion-Related Acute Lung Injury During Orthotopic Liver Transplantation: A Short Report

Transfusion-Related Acute Lung Injury During Liver Transplantation: A Scoping Review

Liver transplantation is associated with significant blood loss, often requiring massive blood product transfusion. Transfusion-related acute lung injury (TRALI) is a devastating cause of transfusion-related deaths. While reports have investigated the general incidence of TRALI, the incidence of TRALI specifically following transfusion during liver transplant remains unclear. This scoping review summarizes existing literature regarding TRALI during the liver transplantation perioperative period. Databases were searched for all articles and abstracts reporting on TRALI after liver transplantation. Data collected included number of patients studied, patient characteristics, incidences of TRALI, TRALI characteristics, and patient outcomes. The primary outcome investigated was the incidence of TRALI in the setting of liver transplantation. Thirteen full-text citations were included in this review. The incidence of TRALI post-liver transplant was 0.68% (65 of 9,554). Based on reported transfusion data, patients diagnosed with TRALI received an average of 10.92 ± 10.81 units of packed red blood cells (pRBC), 20.05 ± 15.72 units of fresh frozen plasma, and 5.75 ± 10.00 units of platelets. Common interventions following TRALI diagnosis included mechanical ventilation with positive end-expiratory pressure, inhaled high-flow oxygen, inhaled pulmonary vasodilator, and pharmacologic treatment using pressors or inotropes, corticosteroids, or diuretics. Based on reported mortality data, 26.67% of patients (12 of 45) diagnosed with TRALI died during the postoperative period. This scoping review underscores the importance of better understanding the incidence and presentation of TRALI after liver transplant surgery. The clinical implications of these results warrant the development of identification and management strategies for liver transplant patients at increased risk for developing TRALI.

Tracheostomy Following Liver Transplantation

BACKGROUND

With increased demand for liver transplantation, sicker patients are being transplanted frequently. These patients are at a higher risk of significant postoperative morbidity, including respiratory failure. This study evaluated the phenotype that characterizes liver transplant candidates who may benefit from early tracheostomy.

METHODS

A single center retrospective review of all liver transplant candidates between January 2012 and December 2017. Patients who eventually required tracheostomies were identified and compared to their counterparts.

RESULTS

Of the 130 liver transplants performed during the study period, 11 patients required tracheostomy. Although patients in the tracheostomized population (TP) did not have significantly worse preoperative functional status (<4 metabolic equivalents; 64% vs 42%, P = .21), they had a higher native model for end-stage liver disease (MELD) score (37 vs 30, P < .05) at the time of transplantation. Patients who eventually succumbed to respiratory failure had lower arterial pressure of oxygen/fraction of inspired oxygen (PaO₂/FiO₂) ratios at the start of surgery and remained unchanged for the duration of surgery compared with the nontracheostomy group (P < .05). TP patients required more net fluid intraoperatively (7.3 vs 5.0 L, P < .05), increased length of time to attempted extubation (3.5 vs 1 day, P < .05), longer ventilation days (15 vs 1 day, P < .05), increased length of stay (37 vs 9 days, P < .05), and higher 1-year mortality (36% vs 8%, P < .05).

CONCLUSIONS

Based on our findings, patients with a high MELD score (>30), net postoperative fluid balance >6 L, and PaO₂/FiO₂ ratio ≤300 who fail to wean off mechanical ventilation after 72 hours may benefit from tracheostomy during the postoperative period.

Transfusion-related Acute Lung Injury in the Perioperative Patient

Transfusion-related acute lung injury is a leading cause of death associated with the use of blood products. Transfusion-related acute lung injury is a diagnosis of exclusion which can be difficult to identify during surgery amid the various physiologic and pathophysiologic changes associated with the perioperative period. As anesthesiologists supervise delivery of a large portion of inpatient prescribed blood products, and since the incidence of transfusion-related acute lung injury in the perioperative patient is higher than in nonsurgical patients, anesthesiologists need to consider transfusion-related acute lung injury in the perioperative setting, identify at-risk patients, recognize early signs of transfusion-related acute lung injury, and have established strategies for its prevention and treatment.

Respiratory Complications Before and After Liver Transplant

Respiratory complications before and after liver transplant are common, diverse, and potentially have a negative impact on patient outcomes. In this review, we discuss the most frequent respiratory conditions that patients may develop in the perioperative period. Their prevention and/or treatment may help to maximize the benefit these patients may derive from liver transplant. This review examines diagnostic and therapeutic approaches to these complications for hepatologists, surgeons, and critical care physicians.

Retrospective Comparative Study on Postoperative Pulmonary Complications After Orthotopic Liver Transplantation Using the Melbourne Group Scale (MGS-2) Diagnostic Criteria

Background

Postoperative pulmonary complications (PPCs) after orthotopic liver transplantation (OLT) are associated with poor postoperative survival. However, there are no standard criteria for diagnosis of PPCs. This retrospective study aimed to explore the reliability of the Melbourne Group Scale version 2 (MGS-2) for determining PPCs after OLT.

Material/Methods

A total of 121 patients were divided into 3 groups. In the PPC and non-PPC groups, PPCs were determined to be present or absent in accordance with both the MGS-2 and the conventional broad criteria for diagnosis of PPCs; in the potential-PPC group, PPCs were determined to be present only in accordance with the conventional broad criteria. The perioperative risk factors for PPCs and prognosis of patients in potential-PPC group were all compared with non-PPC groups and PPC groups.

Results

The preoperative characteristics of patients in the potential-PPC group were similar to those in non-PPC group. The length of intensive care unit stay (2.26±0.22 vs. 4.75±0.47 days; P=0.017), duration of hospitalization (33.33±1.70 vs. 48.78±2.53 days; P<0.001), and treatment cost (28.01±1.78 vs. 38.35±1.85×10 000 yuan; P=0.018) were significantly less in the potential-PPC group than in the PPC group. Furthermore, in accordance with the MGS-2 criteria for diagnosis of PPCs, patients with PPCs showed poorer overall survival rates than those without (P=0.038).

Conclusions

The MGS-2 appears to be a more suitable and reliable tool for diagnosis of PPCs and to identify the post-OLT patients with poorer perioperative characteristics and prognosis.

Intensive Care of Pulmonary Complications Following Liver Transplantation

Chronic liver disease has been associated with pulmonary dysfunction both before and after liver transplantation. Post-liver transplantation pulmonary complications can affect both morbidity and mortality often necessitating intensive care during the immediate postoperative period. The major pulmonary complications include pneumonia, pleural effusions, pulmonary edema, and atelectasis. Poor clinical outcomes have been known to be associated with age, severity of liver dysfunction, and preexisting lung disease as well as perioperative events related to fluid balance, particularly transfusion and fluid volumes. Delineating each and every one of these pulmonary complications and their associated risk factors becomes paramount in guiding specific therapeutic strategies.

Transfusion-Related Acute Lung Injury (TRALI) and Transfusion-Associated Circulatory Overload (TACO) in Liver Transplantation: A Case Report and Focused Review

Liver transplantation (LT) is a complex procedure in a patient with multi-organ system dysfunction and coagulation defects. The surgical procedure involves dissection, major vessel manipulation, and pathophysiologic effects of graft storage and reperfusion. As a result, LT frequently involves significant hemorrhage. Subsequent massive transfusion carries high risk of transfusion-associated complications. Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are the leading causes of transfusion associated mortality. In this case report and focused review, we present data that suggest that patients undergoing liver transplantation may be at higher risk for TRALI and TACO than the general population. Anesthesiologists can play a role in decreasing these risks by increasing recognition and reporting of TRALI and TACO, using point of care testing with thromboelastography to guide and decrease transfusion, and considering alternatives to traditional blood products like solvent/detergent plasma.

Prognostic impact of postoperative low platelet count after liver transplantation

BACKGROUND

The positive impact of platelets has been recently implicated in liver transplantation (LT). The aim of this study was to determine the risk factors for graft loss and mortality after LT, focusing on perioperative platelet counts.

METHODS

We reviewed all deceased donor LT from 2000 to 2012 and enrolled 975 consecutive recipients. The risk factors for graft loss and mortality were analyzed by multivariate analysis, using Cox's regression model.

RESULTS

Using cutoff values acquired by receiver operating characteristics curve analysis, multivariate analyses determined that viral hepatitis C (hazard ratio [HR]=1.32), donor age >40 (HR=1.33), higher peak serum alanine aminotransferase (HR=1.01), reoperation within 30 days (HR=1.51), and platelet count <72 500/μL on postoperative day (POD) 5 (HR=1.30) were independent risk factors for graft loss. Viral hepatitis C (HR=1.33), reoperation within 30 days (HR=1.35), and platelet count <72 500/μL on POD 5 (HR=1.38) were independent risk factors for mortality.

CONCLUSION

A low platelet count on POD 5 was associated with graft loss and mortality after LT. Platelet count <72 500/μL on POD 5 can be a predictor of poor graft and overall survival. Maintaining higher postoperative platelet counts could potentially improve graft and overall survival rates.

Perioperative "remote" acute lung injury: recent update

Perioperative acute lung injury (ALI) is a syndrome characterised by hypoxia and chest radiograph changes. It is a serious post-operative complication, associated with considerable mortality and morbidity. In addition to mechanical ventilation, remote organ insult could also trigger systemic responses which induce ALI. Currently, there are limited treatment options available beyond conservative respiratory support. However, increasing understanding of the pathophysiology of ALI and the biochemical pathways involved will aid the development of novel treatments and help to improve patient outcome as well as to reduce cost to the health service. In this review we will discuss the epidemiology of peri-operative ALI; the cellular and molecular mechanisms involved on the pathological process; the clinical considerations in preventing and managing perioperative ALI and the potential future treatment options.

Hepatic ischemia reperfusion injury: A systematic review of literature and the role of current drugs and biomarkers

Hepatic ischemia reperfusion injury (IRI) is not only a pathophysiological process involving the liver, but also a complex systemic process affecting multiple tissues and organs. Hepatic IRI can seriously impair liver function, even producing irreversible damage, which causes a cascade of multiple organ dysfunction. Many factors, including anaerobic metabolism, mitochondrial damage, oxidative stress and secretion of ROS, intracellular Ca(2+) overload, cytokines and chemokines produced by KCs and neutrophils, and NO, are involved in the regulation of hepatic IRI processes. Matrix Metalloproteinases (MMPs) can be an important mediator of early leukocyte recruitment and target in acute and chronic liver injury associated to ischemia. MMPs and neutrophil gelatinase-associated lipocalin (NGAL) could be used as markers of I-R injury severity stages. This review explores the relationship between factors and inflammatory pathways that characterize hepatic IRI, MMPs and current pharmacological approaches to this disease.