Major Thromboembolic Complications in Liver Transplantation: The Role of Rotational Thromboelastometry and Cryoprecipitate Transfusion.

BackgroundAlthough hemorrhage is a major concern during liver transplantation (LT), the risk for thromboembolism is well recognized. Implementation of rotational thromboelastometry (ROTEM) has been associated with the increased use of cryoprecipitate; however, the role of ROTEM-guided transfusion strategy and cryoprecipitate administration in the development of major thromboembolic complications (MTCs) has never been documented.MethodsWe conducted a study on patients undergoing LT before and after the implementation of ROTEM. We defined MTC as intracardiac thrombus, pulmonary embolism, hepatic artery thrombosis, and ischemic stroke in 30 d after LT. We used a propensity score to match patients during the 2 study periods.ResultsAmong 2330 patients, 119 (4.9%) developed MTC. The implementation of ROTEM was significantly associated with an increase in cryoprecipitate use (1.1 ± 1.1 versus 2.9 ± 2.3 units, P < 0.001) and MTC (4.2% versus 9.5%, P < 0.001). Further analysis demonstrated that the use of cryoprecipitate was an independent risk factor for MTC (odds ratio 1.1, 95% confidence interval 1.04-1.24, P = 0.003). Patients with MTC had significantly lower 1-y survival.ConclusionsOur study suggests that the implementation of ROTEM and the use of cryoprecipitate play significant roles in the development of MTC in LT. The benefits and risks of cryoprecipitate transfusion should be carefully evaluated before administration

Takotsubo syndrome after liver transplantation: An association with intraoperatively administered epinephrine and fentanyl.

Takotsubo syndrome (TTS) can develop after liver transplant (LT), but its predisposing factors are poorly understood. In this study, we aimed to determine if perioperative factors were associated with posttransplant TTS. Adult patients who underwent primary LT between 2006 and 2018 were included. Patients with and without TTS were identified and matched by propensity scores. Of 2181 LT patients, 38 developed postoperative TTS with a mean left ventricular ejection fraction of 25.5% (±7.8%). Multivariable logistic regression revealed two preoperative risk factors (alcoholic cirrhosis and model for end-stage liver disease-sodium scores) for TTS. Post-propensity match analyses showed that TTS patients had significantly higher doses of epinephrine and lower doses of fentanyl during LT compared with non-TTS patients. A higher dose of epinephrine and a lower dose of fentanyl was associated with a higher predicted probability of TTS. All TTS patients had full recovery of cardiac function and had comparable 1-year survival. In conclusion, TTS occurred at a rate of 1.7% after LT and was associated with two pretransplant risk factors. The higher doses of epinephrine and lower doses of fentanyl administered during LT were associated with posttransplant TTS. More studies on the relationship between intraoperative medications and TTS are warranted

Myocardial injury in patients with hemodynamic derangements during and/or after liver transplantation.

Myocardial injury, defined as an elevation of cardiac troponin (cTn) resulting from ischemia, is associated with substantial mortality in surgical patients, and its incidence, risk factors, and impact on patients undergoing liver transplantation (LT) are poorly understood. In this study, adult patients who experienced perioperative hemodynamic derangements and had cTn measurements within 30 days after LT between 2006 and 2013 were studied. Of 502 patients, 203 (40.4%) met the diagnostic criteria (cTn I ≥0.1 ng/mL) of myocardial injury. The majority of myocardial injury occurred within the first three postoperative days and presented without clinical signs or symptoms of myocardial infarction. Thirty-day mortality in patients with myocardial injury was 11.4%, significantly higher compared with that in patients without myocardial injury (3.4%, P<.01). Cox analysis indicated the peak cTn was significantly associated with 30-day mortality. Multivariable logistic analysis identified three independent risk factors: requirement of ventilation before transplant (odds ratios (OR) 1.6, P=.006), RBC≥15 units (OR 1.7, P=.006), and the presence of PRS (OR 2.0, P=.028). We concluded that post-LT myocardial injury in this high-risk population was common and associated with mortality. Our findings may be used in pretransplant stratification. Further studies to investigate this postoperative cardiac complication in all LT patients are warranted

Venovenous Bypass Is Associated With a Lower Incidence of Acute Kidney Injury After Liver Transplantation in Patients With Compromised Pretransplant Renal Function.

BackgroundAlthough the hemodynamic benefits of venovenous bypass (VVB) during liver transplantation (LT) are well appreciated, the impact of VVB on posttransplant renal function is uncertain. The aim of this study was to determine if VVB was associated with a lower incidence of posttransplant acute kidney injury (AKI).MethodsMedical records of adult (≥18 years) patients who underwent primary LT between 2004 and 2014 at a tertiary hospital were reviewed. Patients who required pretransplant renal replacement therapy and intraoperative piggyback technique were excluded. Patients were divided into 2 groups, VVB and non-VVB. AKI, determined by the Acute Kidney Injury Network criteria, was compared between the 2 groups. Propensity match was used to control selection bias that occurred before VVB and multivariable logistic regression was used to control confounding factors during and after VVB.ResultsOf 1037 adult patients who met the study inclusion criteria, 247 (23.8%) received VVB. A total of 442 patients (221 patients in each group) were matched. Aftermatch patients were further divided according to a predicted probability AKI model using preoperative creatinine (Cr), VVB, and intraoperative variables into 2 subgroups: normal and compromised pretransplant renal functions. In patients with compromised pretransplant renal function (Cr ≥1.2 mg/dL), the incidence of AKI was significantly lower in the VVB group compared with the non-VVB group (37.2% vs 50.8%; P = .033). VVB was an independent risk factor negatively associated with AKI (odds ratio, 0.1; 95% confidence interval, 0.1-0.4; P = .001). Renal replacement in 30 days and 1-year recipient mortality were not significantly different between the 2 groups. The incidence of posttransplant AKI was not significantly different between the 2 groups in patients with normal pretransplant renal function (Cr <1.2 mg/dL).ConclusionsIn this large retrospective study, we demonstrated that utilization of intraoperative VVB was associated with a significantly lower incidence of posttransplant AKI in patients with compromised pretransplant renal function. Further studies to assess the role of intraoperative VVB in posttransplant AKI are warranted

Preoperative beta blockade and severe intraoperative bradycardia in liver transplantation.

Nonselective Beta blockade (NSBB) is commonly prescribed for liver transplantation (LT) candidates, but its impact on intraoperative hemodynamics is not well understood. In this study, we investigated if preoperative NSBB was associated with severe bradycardia during LT and if severe intraoperative bradycardia was associated with 30-day mortality. Adult patients undergoing LT between 2005 and 2014 were included. Propensity matching was used to control selection bias. Intraoperative hemodynamics were compared between patients with and without preoperative NSBB. Univariate and multivariate methods were used in statistical analysis. Of 1452 patients, 370 who received preoperative NSBB were matched in a 1:1 ratio with those who did not. Propensity matching eliminated all significant differences between the two groups. Patients who received preoperative NSBB had a significantly higher incidence of severe intraoperative bradycardia compared with the non-BB group (9.6% vs 3.2%, P = 0.001, OR 2.95, 95% CI 1.42-6.12, P = 0.004). Intraoperative hypotension and postreperfusion syndrome were not significantly different between the two groups. Severe intraoperative bradycardia was associated with increased 30-day mortality. In conclusion, preoperative NSBB was associated with severe intraoperative bradycardia in LT. In patients who receive preoperative NSBB, severe intraoperative bradycardia should be closely monitored in LT. Further studies assessing safety of preoperative NSBB and intraoperative bradycardia in LT are warranted

Acute respiratory distress syndrome after orthotopic liver transplantation.

PurposeAcute respiratory distress syndrome (ARDS) is a devastating complication with substantial mortality. The aims of this study were to identify the incidence, preoperative and intraoperative risk factors, and impact of ARDS on outcomes in patients after orthotopic liver transplantation (OLT).Materials and methodsAdult OLT patients between January 2004 and October 2013 at our center were included. Postoperative ARDS was determined using the criteria proposed by the Berlin Definition. Multivariate logistic models were used to identify preoperative and intraoperative risk factors for ARDS.ResultsOf 1726 patients during the study period, 71 (4.1%) developed ARDS. In the preoperative model, encephalopathy (odds ratio [OR], 2.22; P = .022), preoperative requirement of intubation (OR, 2.06; P = .020), and total bilirubin (OR, 1.02; P = .003) were independent risk factors. In the intraoperative model, large pressor bolus was the sole risk factor for ARDS (OR, 2.69; P = .001). Postoperatively, patients with ARDS had a 2-fold increase in 1-year mortality, mechanical ventilation time, and length of hospital stay.ConclusionsAcute respiratory distress syndrome occurred at a rate of 4.1% following OLT in adult patients and was associated with preoperative encephalopathy, requirement of intubation, and total bilirubin and intraoperative large boluses of pressors. Acute respiratory distress syndrome was associated with increased mortality, longer ventilation time, and hospital stay

Acute respiratory distress syndrome after orthotopic liver transplantation.

PurposeAcute respiratory distress syndrome (ARDS) is a devastating complication with substantial mortality. The aims of this study were to identify the incidence, preoperative and intraoperative risk factors, and impact of ARDS on outcomes in patients after orthotopic liver transplantation (OLT).Materials and methodsAdult OLT patients between January 2004 and October 2013 at our center were included. Postoperative ARDS was determined using the criteria proposed by the Berlin Definition. Multivariate logistic models were used to identify preoperative and intraoperative risk factors for ARDS.ResultsOf 1726 patients during the study period, 71 (4.1%) developed ARDS. In the preoperative model, encephalopathy (odds ratio [OR], 2.22; P = .022), preoperative requirement of intubation (OR, 2.06; P = .020), and total bilirubin (OR, 1.02; P = .003) were independent risk factors. In the intraoperative model, large pressor bolus was the sole risk factor for ARDS (OR, 2.69; P = .001). Postoperatively, patients with ARDS had a 2-fold increase in 1-year mortality, mechanical ventilation time, and length of hospital stay.ConclusionsAcute respiratory distress syndrome occurred at a rate of 4.1% following OLT in adult patients and was associated with preoperative encephalopathy, requirement of intubation, and total bilirubin and intraoperative large boluses of pressors. Acute respiratory distress syndrome was associated with increased mortality, longer ventilation time, and hospital stay

Intraoperative Hypertension and Thrombocytopenia Associated With Intracranial Hemorrhage After Liver Transplantation.

BackgroundIntracranial hemorrhage (ICH) is a devastating complication. Although hypertension and thrombocytopenia are well-known risk factors for ICH in the general population, their roles in ICH after liver transplantation (LT) have not been well established.MethodsWe performed a retrospective study and hypothesized that intraoperative hypertension and thrombocytopenia were associated with posttransplant ICH. New onset of spontaneous hemorrhage in the central nervous system within 30 days after LT were identified by reviewing radiologic reports and medical records. Risk factors were identified by multivariate logistic regression. Receiver operating characteristic analysis and Youden index were used to find the cutoff value with optimal sensitivity and specificity.ResultsOf 1836 adult patients undergoing LT at University of California, Los Angeles, 36 (2.0%) developed ICH within 30 days after LT. Multivariate logistic regression demonstrated that intraoperative mean arterial pressure ≥105 mm Hg (≥10 min) (odds ratio, 6.5; 95% confidence interval, 2.7-7.7; P < 0.001) and platelet counts ≤30 × 10/L (odds ratio, 3.3; 95% confidence interval, 14-7.7; P = 0.006) were associated with increased risk of postoperative ICH. Preoperative total bilirubin ≥7 mg/dL was also a risk factor. Thirty-day mortality in ICH patients was 48.3%, significantly higher compared with the non-ICH group (3.0%; P < 0.001). Patients with all 3 risk factors had a 16% chance of developing ICH.ConclusionsIn the current study, postoperative ICH was uncommon but associated with high mortality. Prolonged intraoperative hypertension and severe thrombocytopenia were associated with postoperative ICH. More studies are warranted to confirm our findings and develop a strategy to prevent this devastating posttransplant complication