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Biomedical subjects

J R Lake

Publications and source records attributed to J R Lake.

At least 55 records · Page 3Linked to original sources
PubMed1997

Endoscopic sclerotherapy compared with percutaneous transjugular intrahepatic portosystemic shunt after initial sclerotherapy in patients with acute variceal hemorrhage. A randomized, controlled trial.

BACKGROUND: Hemorrhage from esophageal varices remains a substantial management problem. Endoscopic sclerotherapy was preferred for more than a decade, but fluoroscopically placed intrahepatic portosystemic stents have recently been used with increasing frequency. OBJECTIVE: To compare sclerotherapy with transjugular intrahepatic portosystemic shunt (TIPS) in patients with bleeding from esophageal varices. DESIGN: Randomized, controlled clinical trial. SETTING: Three teaching hospitals. PATIENTS: 49 adults hospitalized with acute variceal hemorrhage from November 1991 to December 1995: 25 assigned to sclerotherapy and 24 assigned to TIPS. INTERVENTION: Patients assigned to repeated sclerotherapy had the procedure weekly. In those assigned to TIPS, an expandable mesh stent was fluoroscopically placed between an intrahepatic portal vein and an adjacent hepatic vein. MEASUREMENTS: Pretreatment measures included demographic and laboratory data. Postrandomization data included index hospitalization survival, duration of follow-up, successful obliteration of varices, rebleeding from varices, number of variceal rebleeding events, total days of hospitalization for variceal bleeding, blood transfusion requirements after randomization, prevalence of encephalopathy, and total health care costs. RESULTS: Mean follow-up (+/-SE) was 567 +/- 104 days in the sclerotherapy group and 575 +/- 109 days in the TIPS group. Varices were obliterated more reliably by TIPS than by sclerotherapy (P < 0.001). Patients having TIPS were significantly less likely to rebleed from esophageal varices than patients receiving sclerotherapy (3 of 24 compared with 12 of 25; P = 0.012). No other follow-up measures differed significantly between groups. A trend toward improved survival, which was not statistically significant, was noted in the TIPS group (hazard ratio, 0.53 [95% CI, 0.18 to 1.5]). CONCLUSIONS: In obliterating varices and reducing rebleeding events from esophageal varies, TIPS was more effective than sclerotherapy. However, TIPS did not decrease morbidity after randomization or improve health care costs. It seemed to produce better survival, but the increase in survival was not statistically significant.

Adult↗
PubMed1997

A controlled analysis of the transjugular intrahepatic portosystemic shunt in liver transplant recipients. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Liver Transplantation Database.

BACKGROUND: The transjugular intrahepatic portosystemic shunt (TIPS) is an important treatment for complications of portal hypertension. As some authors have suggested that TIPS may facilitate liver transplantation technically, the objective of this study was to determine the impact of TIPS on the liver transplant operation and its outcome. METHODS: The analysis was designed as a retrospective cohort study using a multicenter database. Fifty-five patients with TIPS were matched with 55 controls on the basis of 10 pretransplant laboratory, clinical, and demographic features. TIPS patients and control patients were compared with regard to duration of surgery, intraoperative blood product usage, liver and renal function, volume of ascites, survival, and hospital stay. For confirmatory purposes, a parallel analysis using linear regression methods was performed. RESULTS: By matched analysis, TIPS patients had less ascites at surgery (mean 0.9+/-0.20 vs. 2.2+/-0.37 L, P=0.005) and a slightly shorter time from incision to cross-clamp (mean 2.1+/-0.10 vs. 2.5+/-0.15 hr, P=0.03). However, there were not significant differences for total operative time (mean 6.0+/-0.17 vs. 6.3+/-0.25 hr, P=1.00), blood product usage, or any other outcome variable. Regression analysis confirmed these results. CONCLUSIONS: TIPS does not significantly impact the course of liver transplantation surgery. Therefore, preoperative portal decompression solely to facilitate liver transplantation is not an appropriate indication for TIPS.

Cohort Studies↗
PubMed1997

Antibody to the host cellular gene-derived epitope GOR-1 in liver transplant recipients with hepatitis C virus infection.

The presence of anti-GOR was determined in paired pre-orthotopic liver transplantation (pre-OLT) and post-OLT sera from 87 OLT patients with hepatitis C virus infection. Before OLT, 48/87 patients were seropositive for anti-GOR, but this marker had no relationship with the clinical and biochemical parameters, or viremia level. Anti-GOR was less commonly detected in patients infected with genotype 3a, compared with genotypes 1 and 2, which might be related to the less conserved nature of the proposed shared epitope (amino acid sequence 9-18) in genotype 3a isolates. After OLT (median follow-up 16 months), anti-GOR was detected in 31/87 patients and it had no correlation with the clinical and biochemical parameters, viremia level, histologic disease activity, and clinical outcome. Changes in anti-GOR status (before OLT versus after OLT) were also not related to any of the clinical parameters. Although anti-GOR is commonly detected in OLT patients infected with hepatitis C virus genotypes 1 and 2, it has no clinical or prognostic significance.

Adult↗
PubMed1997

The impact of surgical complications after liver transplantation on resource utilization.

OBJECTIVE: To evaluate the impact of surgical complications on length of stay and hospital charges after liver transplantation. DESIGN: A retrospective economic evaluation of the outcomes during initial hospitalization after liver transplantation. SETTING: University hospital treating referred patients. PATIENTS: The study population was 109 patients undergoing 111 liver transplantations during fiscal year 1993. MAIN OUTCOME MEASURES: Hospital charges and length of stay during the initial hospitalization after liver transplantation. Multivariate regression methods were used to analyze the impact of surgical complications on costs. RESULTS: Of the 111 transplantations, 30 (27%) had a surgical complication that required a return to the operating room during the initial hospitalization. The effect of a surgical complication was to increase the mean hospital charges (excluding physician charges) from $150,092 to $347,728 (difference of mean, $197,636; confidence interval of difference, $114,153 to $319,326). The median length of stay was 16 days for patients without complications and 45 days for those with complications. Univariate and multivariate models suggested that surgical complications had the greatest effect on length of stay and hospital charges among the factors studied. Complications tended to occur more frequently among patients with United Network for Organ Sharing (UNOS) status 1 (42% vs 22%), but this did not reach statistical significance (P = .09). CONCLUSIONS: Surgical complications after liver transplantation have a marked impact on the cost of the procedure. The magnitude of this effect is greater than that of UNOS status, presence of rejection, or other demographic or clinical factors studied. Complications tend to occur in the most ill patients. Identifying strategies to reduce the risk of complications, particularly in patients with UNOS status 1, likely can reduce the cost of transplantation.

Adolescent↗
PubMed1997

Hepatitis G virus in patients with cryptogenic liver disease undergoing liver transplantation.

To examine the prevalence of hepatitis G virus (HGV) in end-stage liver disease of unknown cause and the role of HGV infection in posttransplantation hepatitis, we studied 46 patients undergoing liver transplantation (mean age, 50 years; M:F, 18:28) with cryptogenic cirrhosis. HGV RNA was detected by polymerase chain reaction (PCR) and was quantified by a branched DNA (bDNA) assay. The prevalence of HGV RNA was determined in samples collected before and after liver transplantation and was found to be 22% and 67%, respectively. We evaluated the prevalence of posttransplantation hepatitis in 25 patients, 16 of whom were HGV-positive and 9 were HGV-negative. The proportion of patients with hepatitis was not significantly different in the two groups (38% in HGV-positive and 22% in HGV-negative patients). The median histological scores were significantly higher in liver biopsies from patients with HGV infection than in those without HGV infection (2 [range, 0-14] and 1 [range, 0-3]; P = .01), but the histological scores were low overall. The duration of follow-up was similar in the two groups. HGV RNA levels were not correlated with the severity of liver disease based on histological score (r = -.08). Graft survival and patient survival were not significantly different. We concluded that liver disease was frequent (32%) after transplantation in patients with a pretransplantation diagnosis of cryptogenic cirrhosis, although the disease was generally mild. Although HGV RNA was demonstrable in the majority (67%) of patients after transplantation, there was no relationship between the presence of HGV RNA and the presence of posttransplantation liver disease. The finding of posttransplantation hepatitis in the absence of known viruses (A-G), suggests that other, as-yet-unidentified viruses may be important.

Adult↗
PubMed1997

Changes in quality of life after liver transplantation among adults. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Liver Transplantation Database (LTD).

Quality of life is an important factor to consider when assessing the value of liver transplantation. Using a large, prospective database of liver transplantation recipients from three clinical centers in the United States, we examined the quality of life of 346 adults before and 1 year after surgery. Five quality of life domains were evaluated (measures of disease, psychological distress and well-being, personal function, social/role function, and general health perception) with standardized questionnaires completed according to established protocol. The largest numbers of patients were distressed by fatigue and muscle weakness, both before transplantation and 1 year after surgery. Compared to baseline, recipients at follow-up noted fewer disease-related symptoms (P < .001) and lower levels of distress overall (P < .001). However, levels of distress due to excess appetite (P < .001), headaches (P = .02), and poor/blurred vision (P = .05) were more likely to increase than decrease. Although 57% to 64% of the recipients were distressed by each of the psychological conditions examined at follow-up, distress was more likely to decrease than increase (P < .001), and well-being was comparable to the general population. All measures of personal functioning improved significantly (P < .05). Fifty-eight percent of the patients prevented by their disease from going to work or school before transplantation were no longer so limited at follow-up. With the exception of marriage (P = .23), all facets of social/role functioning improved more often than worsened (P < .01). Perception of health improved remarkably, with 13.4 times as many recipients reporting improved health as reporting worse health (P < .001). We conclude that liver transplantation markedly improves the quality of life of patients with end-stage liver disease.

Adolescent↗
PubMed1997

Minimal criteria for placement of adults on the liver transplant waiting list: a report of a national conference organized by the American Society of Transplant Physicians and the American Association for the Study of Liver Diseases.

This report summarizes a recent meeting cosponsored by the American Society of Transplant Physicians and the American Association for the Study of Liver Diseases to formulate minimal criteria by which patients with severe liver disease will be placed on the waiting list for liver transplantation. The participants agreed that only patients in immediate need of liver transplantation should be placed on the waiting list. Patients should not be placed in anticipation of some future need for such therapy. It was agreed that minimal criteria could assist but not replace the clinical judgment of the transplant professionals at individual centers. The criteria will be summarized below for adult patients with acute or chronic liver disease. The most important non-disease-specific criterion for placement on the transplant waiting list was an estimated 90% chance of surviving 1 year. This translated into a Child-Pugh score of > or = 7 for patients with cirrhosis which places the patient in Child-Pugh class B or C. Cirrhotic patients who have experienced gastrointestinal bleeding caused by portal hypertension or a single episode of spontaneous bacterial peritonitis would meet the minimal criteria irrespective of their Child-Pugh score. There were disease-specific criteria also. These include a sole minimal criterion for patients with fulminant hepatic failure regardless of etiology of the onset of stage 2 hepatic encephalopathy. A requirement for 6 months abstinence from alcohol before placement on the transplant waiting list was considered appropriate for most patients with alcoholic liver disease. Exceptional cases could get access to the waiting list through a regional review process. Chronic cholestatic diseases present difficulties because of a different natural history than that of chronic hepatocellular diseases. The use of specific risk scores for primary biliary cirrhosis and primary sclerosing cholangitis will likely replace Childs-Pugh classification as the scoring systems become refined. Minimal criteria for any patient with a primary hepatocellular cancer would admit any patient with a tumor confined to the liver irrespective of size or number of tumors, after careful investigation had failed to show spread to lymph nodes, the portal vein, or distant organs. Unusual or rare indications for liver transplantation, including Budd-Chiari syndrome, Wilson's disease, and other hereditary disorders, were also discussed. Finally, it was agreed that there should be no absolute contraindications to placement of patients on the liver transplant waiting list. These criteria should be open to regular review to accommodate advances in the field.

Adult↗
PubMed1997

Nicotine abstinence syndrome precipitated by central but not peripheral hexamethonium.

A rodent model of nicotine dependence has been developed based on continuous subcutaneous (s.c.) infusion of nicotine tartrate. Nicotine abstinence syndrome was precipitated by s.c. injection of the nicotinic antagonist mecamylamine, which freely crosses the blood-brain barrier. In contrast, the nicotinic antagonist hexamethonium crosses the blood-brain barrier very poorly. This study determined whether central or peripheral administration of hexamethonium could precipitate nicotine abstinence. In the first experiment, 26 nicotine-dependent rats were injected s.c. with 0.5, 5 or 10 mg/kg hexamethonium dichloride or saline alone and observed for 20 min. Few abstinence signs were observed in any group; there was no significant drug effect. In the second experiment, 18 rats were cannulated in the third ventricle and rendered nicotine dependent. One week later, rats were injected through the cannula with 12 or 18 ng hexamethonium or saline alone and observed for 20 min. Both dose groups differed significantly from the saline-injected group, and there was a significant positive linear trend of signs as a function of dose. The high dose had no significant effect in 14 nondependent rats. We conclude that hexamethonium is much more potent by the central route, and there is a major central nervous system component in nicotine dependence.

Animals↗
PubMed1997

Selection of patients for liver transplantation in 1997 and beyond.

Liver transplantation is now accepted as the standard surgical-medical treatment for end-stage liver disease, as well as replacement therapy for certain inborn errors of metabolism. While improvements in surgical methods and new immunosuppressive agents have improved survival, there remains a chronic shortage of available donor organs. This article offers guidelines for the physician, discussing indications for liver transplantation, controversial selection issues, contraindications, and finally, the future of liver transplantation.

Contraindications↗
PubMed1997

Transmission of hepatitis B by transplantation of livers from donors positive for antibody to hepatitis B core antigen. The National Institute of Diabetes and Digestive and Kidney Diseases Liver Transplantation Database.

BACKGROUND & AIMS: Organ donors are a potential source of transmissible disease after transplantation. The aim of this study was to evaluate the risk of acquiring hepatitis B among transplantation recipients of livers from donors without serum hepatitis B surface antigen (HBsAg) but with antibody to hepatitis B core antigen (anti-HBc). METHODS: The transplantation experience of four centers between 1989 and 1994 was reviewed. Recipients of livers from 674 donors were considered informative for hepatitis B virus transmission. RESULTS: Hepatitis B developed in 18 of 23 recipients of livers from anti-HBc-positive donors (78%) compared with only 3 of 651 recipients of anti-HBc-negative donor livers (0.5%) (P < 0.0001). HBsAg persisted in all recipients with donor-related hepatitis B. Liver histology showed chronic hepatitis of moderate severity in 2 of 13 recipients at 1 year and 5 of 8 recipients between 1.6 and 4.5 years from transplantation. Liver transplantation from an anti-HBc-positive donor was associated with decreased 4-year survival (adjusted mortality hazard ratio of 2.4; 95% confidence interval, 1.4-4.0). CONCLUSIONS: De novo posttransplantation hepatitis B infection occurs at a high rate in recipients of donors with anti-HBc. Transmission of hepatitis B through transplantation suggests that the virus may persist in the liver despite serological resolution of infection.

Hepatitis B↗
PubMed1997

Transjugular intrahepatic portosystemic shunt as a form of treatment for portal hypertension: indications and contraindications.

The TIPS clearly has had a major impact on the treatment of complications of portal hypertension in the cirrhotic patient. Currently, TIPS is performed in community hospitals as well as university centers in the United States. While the shunt is placed under local anesthesia in a nonoperative fashion, it must be remembered that it does function as a highly effective side-to-side shunt with its attendant complications including hepatic encephalopathy and occasional liver failure. Early reports of clinical and hemodynamic results after TIPS have clearly demonstrated it to be an effective bridge to liver transplantation. Nonetheless, transplantation candidates who experience their initial episode of variceal hemorrhage still should be managed with sclerotherapy or variceal band ligation. However, if bleeding recurs during a course of treatment or cannot be acutely controlled, TIPS has proved invaluable in stabilizing patients prior to liver transplantation. Refractory variceal bleeding in Child's class C patients, in whom the perioperative mortality associated with surgical shunts is high, is also reasonable indication for TIPS. Potential, but less well-proved indications for TIPS include refractory ascites, hepatic hydrothorax, and the Budd-Chiari syndrome. Refractory variceal hemorrhage in Child's class A or B patients, bleeding from portal hypertensive gastropathy, and HRS represent possible, but unproved, indications. Preoperative reduction in portal hypertension prior to liver transplantation does not appear to represent an appropriate indication for TIPS. In spite of the wide acceptance of TIPS, it will be important to continue to study its indications and its complications so that it can be optimally used in the treatment of patients with portal hypertension.

Algorithms↗
PubMed1996

Outcome of patients with renal insufficiency undergoing liver or liver-kidney transplantation.

Renal insufficiency (RI) is a common finding with end-stage liver disease. RI is generally not regarded as a contraindication to liver transplantation. However, the impact of RI on outcome following transplantation and the role of combined liver-kidney transplant are not well understood. The effect of RI on patients with fulminant hepatic failure (FHF) or chronic liver disease (cirrhosis) was investigated using the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Liver Transplantation Database. Patients were analyzed based on the presence of RI, defined as creatinine >1.6 mg/dl, or on dialysis. Patients undergoing liver-kidney transplantation were analyzed separately. For patients with FHF, the RI group had a lower patient survival rate at 1 year (50% vs. 83%, P=0.04) and tended to have a lower graft survival rate (50% vs. 71%). Stay in the intensive care unit (ICU) was prolonged in the RI group but hospital stay was not. Among patients with cirrhosis, RI did not affect patient survival, except for patients on dialysis or those with liver-kidney transplants. One-year patient and graft survival rates were 65% and 60% for the dialysis group, 74% and 70% for the liver-kidney transplant group, 89% and 86% for RI patients not on dialysis, and 89 and 84% for non-RI patients. ICU and hospital stays were prolonged for all of the RI groups compared with the non-RI patients. Patients with RI had higher rates of posttransplant dialysis; however, the differences tended to equalize after 4 weeks. We conclude that RI in FHF and RI requiring dialysis or liver-kidney transplantation in cirrhosis predict lower posttransplant patient and graft survival rates. Patients with RI have longer hospital and ICU stays and an increased need for dialysis, which likely increases the cost of transplantation. Whether liver-kidney transplantation improves outcome and thus represents an appropriate use of cadaver kidneys requires further study.

Adult↗
PubMed1996

Incidence and significance of Aspergillus cultures following liver and kidney transplantation.

Aspergillus infection is a rare but devastating complication following solid organ transplantation, with mortality rates that approach 100%. Aspergillus species (sp) are also ubiquitous in our environment and may contaminate culture plates. To determine the significance of positive Aspergillus cultures, we analyzed all positive cultures from the liver and kidney transplant services at our center for the treatments used and clinical outcomes. Aspergillus sp. were cultured from 4.5% of liver and 2.2% of kidney transplant recipients. A. fumigatus was the most common isolate, followed by A. niger and A. flavus. The lung was the most common site of positive cultures. Body fluids (ascites, pleural fluid) were common sources of positive cultures but were never associated with clinical disease. Positive brain biopsies occurred in 10% of patients. Analysis of risk factors for significant infection revealed that cultures with >2 colonies or more than one site of infection were predictive of significant infection and portended a poor prognosis even with aggressive therapy. Two or fewer colonies from a single site likely represented contamination and may be followed with repeat cultures. The high mortality rate associated with Aspergillus sp. infections in transplant recipients highlights the need for better anti-fungal prophylaxis and treatment.

Adult↗
PubMed1996

Fibrosing cholestatic hepatitis in renal transplant recipients.

Fibrosing cholestatic hepatitis in a specific histologic manifestation of hepatitis B virus infection consisting of periportal fibrosis, hepatocyte ballooning, cholestasis, a relatively scant inflammatory infiltrate, and marked overexpression of hepatitis B viral antigens in hepatocytes. Until recently, fibrosing cholestatic hepatitis had been reported only in recipients of liver allografts. In this report, we present two patient in whom this lesion developed following renal transplantation. Both patients had previous liver biopsies showing relatively mild histologic changes. In one patient, the lesion developed early after retransplantation, during the period of maximal immunosuppression. However, in the second patient this lesion developed after withdrawal of immunosuppression. In both cases, death occurred within a few months because of progressive liver disease. Since this lesion can develop in "relatively healthy" hepatitis B carriers following transplantation of organs other than liver, these patients should have careful monitoring of their liver disease. Moreover, since the disease may progress despite withdrawal of immunosuppression, these patients would clearly benefit from the development of more effective therapies for posttransplant hepatitis B.

Adult↗
PubMed1996

The use of the T tube after orthotopic liver transplantation.

An end-to-end choledochocholedochostomy (CD) over a T tube or a Roux-en-Y choledochojejunostomy (CDJ) have been the standard method of biliary reconstruction following orthotopic liver transplantation (OLTx). The objective of this study was to assess whether or not use of the T tube leads to increased biliary tract complications. Biliary tract complications were categorized as bile leak, stenosis, or obstruction that required therapeutic intervention. OLTx was performed in 161 patients over an 18-month period. Fifty-one patients were excluded from the study leaving a total of 110 patients for evaluation. Fifty-nine had their bile duct reconstructed over a T tube (CD T tube, group I) while the remaining 51 patients underwent bile duct reconstruction without a T tube (CD, group II). No difference was noted between groups I and II in their survival rate, rate of conversion to Roux-en-Y CDJ, or biliary complication rates. Our results indicate that CD (i.e., without a T tube) is both a safe and effective technique to reconstruct the biliary tract following hepatic transplantation. Routine use of a T tube with a CD anastomosis is unnecessary in most liver transplant patients. In addition, the omission of a T tube has reduced the number of radiological procedures performed at our center.

Biliary Tract Diseases↗