Preoperative Encephalopathy Research Articles

Is Cardiac Surgery Safe in Patients with Previous Liver Transplantation? A Narrative Review

Background Liver transplant patients have increased risk of developing cardiovascular disease and the outcome of these patients following cardiac surgery has been reported in small series of patients. The aim of this review was to examine and report safety outcomes of liver transplant patients undergoing cardiac surgery. Methods Literature review was conducted using three databases from inception to June 2023. Multiple search terms were used and limited to English language. Nine relevant articles were included. Outcomes of interest were short-term mortality, long-term survival, liver graft failure, major morbidity and infection in liver transplant recipients undergoing cardiac surgery. Results Cardiac risk factors (diabetes mellitus, hypertension, hyperlipidemia) were prevalent in liver transplant patients. 30-days mortality ranged across the studies from zero to 23.8%. 1-year survival ranged from 74-91% and 5-years survival ranged from 33-69%. Commonest causes of death were cardiac and sepsis. Predictors of mortality were preoperative encephalopathy, pulmonary hypertension, blood transfusion and postoperative increase in creatinine and bilirubin levels. Liver allograft rejection ranged from zero to 4.7% with no predictors reported. Liver dysfunction was seen in 33-46% of patients, and all were transient with recovery at the time of hospital discharge. Major morbidities were commonly reported and included respiratory and renal failure. Infection rates ranged from zero to 38% and the most common reported sites were pneumonia, sepsis, and surgical site infections. Conclusion Cardiac surgery can be performed in liver transplant patients with good short- and long-term results and acceptable morbidities.

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.

Predictive factors of neurological complications and one-month mortality after liver transplantation.

Background: Neurological complications are common after orthotopic liver transplantation (OLT). We aimed to characterize the risk factors associated with neurological complications and mortality among patients who underwent OLT in the post-model for end-stage liver disease (MELD) era.Methods: In a retrospective review, we evaluated 227 consecutive patients at the Keck Hospital of the University of Southern California before and after OLT to define the type and frequency of and risk factors for neurological complications and mortality.Results: Neurological complications were common (n = 98), with encephalopathy being most frequent (56.8%), followed by tremor (26.5%), hallucinations (11.2%), and seizure (8.2%). Factors associated with neurological complications after OLT included preoperative dialysis, hepatorenal syndrome, renal insufficiency, intra-operative dialysis, preoperative encephalopathy, preoperative mechanical ventilation, and infection. Preoperative infection was an independent predictor of neurological complications (OR 2.83, 1.47–5.44). One-month mortality was 8.8% and was independently associated with urgent re-transplant, preoperative intubation, and intra-operative arrhythmia.Conclusion: Neurological complications are common in patients undergoing OLT in the post-MELD era, with encephalopathy being most frequent. An improved understanding of the risk factors related to both neurological complications and one-month mortality post-transplantation can better guide perioperative care and help improve outcomes among OLT patients.

Variables Affecting Long Term Survival after Liver Transplantation.

Introduction: Understanding which variables are significant in long- term survival of liver transplant patients is essential for properly informing recipients of outcomes and in the improvement of transplant center outcome measures. Recipient and donor variables for patients with long- term survival, greater than 20 years, hold vital information regarding improvement in elongation of graft survival and donor selection. Methods: A retrospective review of our extensive liver transplant data registry was conducted, and recipient and donor characteristics were examined. Patients with greater than 20- year survival were compared to patients surviving less than 1 year in the same time period of transplantation. Univariate and stepwise multiple logistic regression analyses were performed to compare recipient and donor variables in these two groups. Results: Our liver transplant registry between 1985 and 1995 was analyzed for patient and donor qualities of significance in long- term outcomes. Patients with >20 years survival (N=211) were compared to patients with <1- year survival (N=128). Donor age <55 years (p=0.0027) was the most predictive donor quality indicator of long- term survival. However, donor sex, race, cause of death, and location (local vs. regional vs. national) were not significant. Recipient age <60 years (<0.0001), primary diagnosis (p<0.0001), acquired respiratory infection (p=0.0004), MELD <20 (p=0.0271), were prognostic of long- term survival. Recipient race, diagnosis of HCV, BMI, preoperative encephalopathy, preoperative renal impairment, preoperative INR >1.5, recurrent disease, cold ischemia time, MELD >30, and ABO compatibility did not have a substantial impact on recipient survival. Conclusions: Examination of the extensive liver transplant registry permits the identification of potential ideal donor and recipient characteristics, contributing to extended graft and patient survival. Donor age, recipient age, primary diagnosis, and MELD scores should be rigidly scrutinized to optimize long- term survival and transplant center outcomes.

Surgical outcomes after cardiac surgery in liver transplant recipients

This was a single-center retrospective study to assess the surgical outcomes and predictors of mortality of liver transplant recipients undergoing cardiac surgery. From 2000 to 2010, 61 patients with a functioning liver allograft underwent cardiac surgery. The mean interval between liver transplantation and cardiac surgery was 5.4 ± 4.4 years. Of the 61 patients, 33 (54%) were in Child-Pugh class A and 28 in class B. The preoperative and postoperative data were reviewed. The overall in-hospital mortality was 6.6%. The survival rate was 82.4% ± 5.1% at 1 year and 50.2% ± 8.2% at 5 years. Cox regression analysis identified preoperative encephalopathy (odds ratio, 5.2; 95% confidence interval, 1.8-15.5; P = .003) and pulmonary hypertension (odds ratio, 3.5; 95% confidence interval, 1.3-9.4; P = .045) as independent predictors of late mortality. The preoperative Model for End-Stage Liver Disease (MELD) scores of patients who died in-hospital or late postoperatively were significantly greater statistically than the scores of the others (in-hospital death, 23.7 ± 7.8 vs 13.1 ± 4.5, P < .001; late death, 15.2 ± 6.1 vs 12.3 ± 4.1, P = .038). The Youden index identified an optimal MELD score cutoff value of 13.5 (sensitivity, 56.0%; specificity, 67.6%). Kaplan-Meier survival analysis successfully demonstrated that the survival rate of the MELD score less than 13.5 (MELD <13.5) group was significantly greater than that of the MELD >13.5 group (MELD <13.5 group, 93.8% ± 4.2% at 1 year and 52.4% ± 11.8% at 5 years; MELD >13.5 group, 66.9% ± 9.6% at 1 year and 46.1% ± 11.1% at 5 years; P = .027). In contrast, the survival rate when stratified by Child-Pugh class (class A vs B) was not significantly different. Cardiac surgery in the liver allograft recipients was associated with acceptable surgical outcomes. Preoperative encephalopathy and pulmonary hypertension were independent predictors of late mortality. The cutoff value of 13.5 in the MELD score might be useful for predicting surgical mortality in cardiac surgery.

Are all readmissions the same?

The Patient Protection and Medicare Affordable Care Act (PPACA) is designed to improve the quality and reduce the costs of our health care system. With the Supreme Court recently upholding the tenets of PPACA, hospital readmissions will be further scrutinized: first, payments from the Centers for Medicare and Medicaid Services will be restricted for 3 conditions (pneumonia, heart failure, and myocardial infarction), and later, these restrictions will be broadened to all readmissions that are deemed to be avoidable. Liver transplantation, a high-cost service prone to readmissions in the first year after transplantation, is a likely target. In this issue of Liver Transplantation, Pereira et al. examine the clinical factors predicting readmission after liver transplantation. They report the largest single-center experience to date and assess readmissions for 766 patients who underwent transplantation between 2003 and 2010. The authors have identified a 45% 30-day readmission rate and disease-specific predictors: portal vein thrombosis before transplantation, hospitalization within 90 days before liver transplantation, renal insufficiency (creatinine > 1.9 mg/dL), and hypoalbuminemia (albumin 60 years old), higher Model for End-Stage Liver Disease scores (>19), preoperative encephalopathy, and marked muscle wasting are associated with a higher requirement for institutional care (eg, a skilled nursing facility) after discharge. These observations, gleaned from a large, single-center cohort, add important knowledge about factors associated with higher readmission rates after liver transplantation. Notwithstanding the laudable intentions behind PPACA provisions and the threat of future penalties imposed by the Centers for Medicare and Medicaid Services on the basis of those provisions, it is important to note that there are subtle but important confounding issues that may affect the present and future recording and reporting of readmission rates. For example, it is intuitive that shortening the original length of stay (LOS) after a procedure without the establishment of safety nets akin to medical homes will result in a higher readmission rate simply because if the LOS is longer, complications after transplantation will be managed during the original admission instead of requiring readmission within a few days of discharge. In addition, there is a recent trend showing a sharp rise in observation status for Medicare beneficiaries associated with a sharp decline in admission status. Although observation is expected to last <48 hours, there is no Medicare rule for how long patients can remain in this status, so observation status can be used to avoid any penalty associated with readmissions. Finally, for non-Medicare beneficiaries, payments for transplant services are already bundled so that case rates include certain readmissions and especially those related to transplant episodes. These contractual agreements include the sharing of financial risk with the provider: both LOS and readmission costs

507 Warren-Zeppa Distal Splenorenal Shunts

To define the long-term characteristics, prognostic factors, and outcomes of patients undergoing selective splenorenal shunting procedures for portal hypertension-induced recurrent upper gastrointestinal bleeding. A retrospective evaluation of a prospectively collected data set. From June 1971 through May 2005, 507 Warren-Zeppa shunts were performed at a single institution. Indications included: alcoholic cirrhosis, 52.6%; viral cirrhosis, 21.8%; cryptogenic cirrhosis, 8.4%; autoimmune cirrhosis, 5.8%; and other causes, 6.3%. Median survival was 81 months (5-year survival, 58.9%; 10-year survival, 34.4%; 20-year survival, 12.5%). patients with portal vein thrombosis and biliary cirrhosis demonstrated better survival than others (P = 0.03), while patients with alcoholic cirrhosis trended toward worse survival than those with nonalcoholic causes (P = 0.11). Multivariate analysis of preoperative risk factors found body hair loss (hazard ratio, 17.3; P > 0.005), preoperative encephalopathy (hazard ratio, 1.93; P > 0.003), diuretic use (hazard ratio, 1.43; P > 0.003), and age (hazard ratio, 1.02 per year of age; P > 0.051) were independent predictors of poor long-term survival. Multivariate analysis of operative factors demonstrated blood loss <500 mL was predictive of up to a 4-fold improved long-term survival (hazard ratio, 3.95; P < 0.013). Postoperative complications included: recurrent bleeding, 12%; ascites, 17.5%; and encephalopathy, 13.9%. Multivariate analysis of postoperative factors prospectively collected in 130 patients found that alcoholic recidivism (hazard ratio, 2.66; P > 0.001) was the only independent predictor of poor prognosis. The Warren-Zeppa shunt provides long-term survival and control of bleeding in most patients with portal hypertension. Excellent long-term survival can be obtained in properly selected patients with portal hypertension and relatively spared hepatic function.

Living-donor liver transplantation for fulminant hepatic failure in adult patients with a left-lobe graft

Living donors are practically the only source of organs in countries where the availability of cadaveric donors is severely restricted, such as Japan. A left-lobe graft, in which one third of the liver is donated, is therefore used for adult-to-adult living-donor liver transplantation (LDLT) in patients with fulminant hepatic failure (FHF). Fifteen adult patients with FHF, ranging from 22 to 59 years of age, were treated with LDLT with a left-lobe graft. Preoperative encephalopathy was grade II in 2 patients, grade III in 4 patients, and grade IV in 9 patients. The graft volume (GV) ranged from 260 to 570 mL, thus corresponding to 23% to 54% of the recipients' standard liver volume (SLV). The patients were divided into 2 groups according to their GV/SLV: a medium-size graft group (GV/SLV > or =30%; group M, n = 11) and a small-size graft group (GV/SLV <30%; group S, n = 4). The effects of GV/SLV on graft function and survival were compared. Postoperative neurologic complications were also evaluated. The donors are all doing well. Twelve (80%) of the 15 recipients are still alive, with a follow-up period of from 3 to 43 months. No statistically significant differences were observed in the postoperative serum levels of bilirubin and alanine aminotransferase, prothrombin time, or frequency of postoperative complications between the 2 groups. The graft and patient survival rates were 75% (3/4) and 75% (3/4) in group S and 73% (8/11) and 82% (9/11) in group M, respectively. All patients who survived the perioperative period recovered without any neurologic sequelae. The high success rate and low donor risk of LDLT may therefore justify its use for adult patients with FHF using a left-lobe graft.

Use of distal splenorenal shunt in children referred for liver transplant evaluation

Variceal bleeding remains a common cause of morbidity for children with both intrahepatic and extrahepatic portal hypertension. Occasionally, patients referred for liver transplant evaluation have significant variceal bleeding, despite adequate synthetic liver function. During a 7-year period, 322 children were referred for liver transplant evaluation. Six underwent distal splenorenal shunt surgery after evaluation. There were four boys and two girls. The average age was 11 ± 4 years, and the average weight was 39 ± 15 kg. The etiology of variceal bleeding was intrahepatic portal hypertension in five (1 biliary atresia, 2 chronic hepatitis, 2 congenital hepatic fibrosis) and extrahepatic portal vein thrombosis in one. Two patients had no previous attempts at sclerotherapy (one because of an abnormality in platelet function, the other because of extensive gastric varices), and four had multiple previous sclerotherapy treatments. No patient had preoperative encephalopathy. Three cases were Child's class A, and three were Child's class B. Preoperative evaluation of the portasystemic system was performed with magnetic resonance (MR) imaging or splenoportography. All patients underwent a distal splenorenal shunt procedure, four of whom also had splenopancreatic disconnection. One patient required 100 mL of blood replacement, and five required no blood. The average length of hospital stay was 9.8 ± 2.2 days. Postoperative complications were minimal. All patients are alive, without recurrent gastrointestinal bleeding or encephalopathy, and they have patent shunts, which was confirmed by MR or Doppler ultrasound at a mean of 25 ± 20 months after shunt surgery. Children who have significant cirrhosis, portal hypertension, recurrent variceal bleeding refractory to sclerotherapy, and adequate synthetic function can be effectively treated with a distal splenorenal shunt. While the choice between liver transplantation of shunting may be difficult, use of the distal splenorenal shunt does not preclude future liver transplantation for such children.

Prospective study of portasystemic encephalopathy after emergency portacaval shunt for bleeding varices

A prospective study of the development of encephalopathy was undertaken in 180 patients undergoing emergency portacaval shunt for bleeding esophageal varices between 1963 and 1978. The incidence of preoperative encephalopathy was 32 percent. Postoperatively, encephalopathy developed in 31.5 percent of 95 survivors and was severe in 7 percent of those survivors. Encephalopathy developed in most patients in the first and second follow-up years; in 10 year survivors, encephalopathy was virtually absent. Encephalopathy was more likely to occur in patients with encephalopathy at the time of shunt and in those who returned to alcoholism after shunt. Most encephalopathic episodes were precipitated by dietary indiscretion, often associated with alcoholism. Careful follow-up with attention to dietary compliance and abstinence from alcohol should make the risk of encephalopathy acceptable in relation to the unquestionable benefits of portacaval shunt in reducing the risk of variceal hemorrhage.

Dacron interposition shunts for portal hypertension. An analysis of morbidity correlates.

Analysis of 79 Dacron interposition shunts performed at Emory University from 1971 to 1977 identified a number of preoperative characteristics that correlate with short-term and long-term morbidity. Initial hospital mortality was related to the degree of elevation of the bilirubin and serum glutamic oxaloacetic transaminase (SGOT), to the presence of encephalopathy and to the urgency of the shunt procedure. Cumulative survival correlated best with the preoperative SGOT and bilirubin values, but other variables, including the Child's classification, preoperative encephalopathy, serum albumin, and the age of the patient at the time of operation, also exhibited significant associations. The hospital mortality of 13% and cumulative mortality of 48% in this series are in substantial agreement with similar reports in the literature. This experience differs widely from that described by most authors, however, in two other important respects: 1) significant hepatic encephalopathy has been observed in 45% of these hospital survivors, and 2) almost one-quarter of these patients have experienced spontaneous shunt closure. Thus, major shunt related complications have occurred in 70% of the patients to date. This incidence of undesirable consequences raises a serious question concerning the continued use of the Dacron interposition shunt for elective portal decompression.

Biosynthesis of insulin. The Ferdinand-Bertram-Award lecture (author's transl)

EEG recordings were done 1-3 months before and up to 5 years after shunt operations in 20 men and 7 women (aged 16 to 69 years) with liver cirrhosis, most of them of alcoholic aetiology, and with oesophageal bleeding. The EEG diagnosed encephalopathies before there were any clinical suspicions. Pre-operatively half of the patients (14) had EEG changes indicating encephalopathy. In only four patients who before operation had a normal EEG were there post-operative EEG changes indicating encephalopathy. In the other nine patients the EEG was normal before and after shunt operation. The abnormal EEGs which occurred post-operatively or got worse generally returned to pre-operative levels within 3-4 weeks. These studies indicate that in patients with pre-operative encephalopathy there is no improvement in the EEG after shunt operation. On the other hand, if pre-operatively there are no significant cerebral abnormalities, post-operative changes of encephalopathy are rare (14.8%).

Comparative group study between patients surviving five or more years after portacaval shunt procedure and those surviving less than one year

The classic criteria utilizing preoperative clinical evaluations and laboratory tests for predicting risk and long-term survival in cirrhotic patients undergoing portacaval shunting still appear to be the most useful. Analysis of the factors that could be determinant in separating patients who are going to survive a portacaval shunt for five or more years from the short-term survivors revealed the former group had a lesser incidence of preoperative encephalopathy, ascites, malnutrition, and hypoalbuminemia. None of the intraoperative factors were found to be decisive. However, the prompt and uncomplicated postshunt recovery was an accurate prediction for long-term survival. This could be explained by the assumption that these patients had a better hepatic functional reserve at the time of portal-systemic shunting. The early appearance in the postoperative period, of fluid retention, azotemia, oliguria, inability to eat, and the early appearance of the symptoms of portal encephalopathy were premonitory of short-term survival. Return to alcohol ingestion was also associated with short-term survival. The hepatorenal syndrome was usually the cause of death in the short-term survivors whereas nonhepatic disease was the cause of demise in the long-term survivors. The operative mortality for all patients undergoing portacaval shunting during an eight year period was 10.7 per cent. Of the patients who left the hospital alive, 16.1 per cent died within the subsequent twelve months, 53 per cent survived from thirteen to fifty-nine months after their operation, and 19.6 per cent survived sixty or more months.