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S J Knechtle

Publications and source records attributed to S J Knechtle.

At least 109 records · Page 6Linked to original sources
PubMed1994

Portal hypertension: surgical management in the 1990s.

BACKGROUND: Although liver transplantation offers definitive treatment for portal hypertension with end-stage liver failure, surgical portosystemic shunts avoid the risks of transplantation and immunosuppressive therapy, and transjugular intrahepatic portosystemic shunt (TIPS) creates a portosystemic shunt with minimal operative risk. The appropriate applications of these modalities are discussed. METHODS: All adults undergoing primary liver transplantation alone (PLT, n = 265), PLT after TIPS (n = 34), PLT after surgical shunts (n = 12), surgical shunt alone (n = 13), TIPS alone (n = 35), or surgical shunt after PLT (n = 5) served as the basis of this study. RESULTS: In contrast to surgical shunts before PLT, TIPS before PLT increased the 1-year graft survival. Surgical shunts alone were done in 18 patients with normal or near normal liver function with 100% survival. TIPS alone offered effective symptomatic relief to most patients, all of whom were judged not to be surgical candidates. CONCLUSIONS: TIPS, surgical shunts, and liver transplantation each have a logical role in management of portal hypertension. Surgical candidates with Child's B or C liver failure should be treated with liver transplantation, and TIPS offers effective treatment for nonsurgical candidates. Surgical shunts can be performed with excellent results in patients with Child's A liver disease. Portal vein occlusion with normal liver function can be successfully treated with surgical shunts.

Adolescent↗
PubMed1994

Urological complications and enteric conversion after pancreas transplantation with bladder drainage.

In summary, we feel that excellent 5-year patient and graft survival results can be obtained using SPK transplantation with bladder drainage technique. Despite the good results, a significant morbidity with prolonged hospitalization is seen after pancreas transplantation. This increased morbidity is due to infectious complications, rejection and urological complications. As a result of the popularity of bladder drainage, the complications after pancreas transplantation have shifted from intraabdominal to urological. Enteric conversion after SPK transplantation is the treatment of choice for chronic hematuria and a duodenal segment leak. In our hands this method appeared to be a safe and reliable procedure with a low complication rate. Enteric conversion should be considered in early leaks after failure of one attempt to suture repair the anastomotic site. In larger leaks or late leaks, it is advisable to perform an immediate enteric conversion. With the considerations above one might ask why enteric conversion is not our current primary choice for the initial transplant procedure. We have, however, noted a higher incidence of postoperative intraabdominal septic complications as well as mycotic aneurysms at the arterial suture line in a small series of 16 primarily enterically drained pancreas transplants. We also fear that the leakage rate after primary duodenoenteric drainage could be higher because of significant edema after transplantation in the preserved duodenal segment. We doubt, therefore, that the primary anastomosis with the bowel is as safe as one performed during enteric conversion when preservation injury has been resolved. At that point the patient is in stable condition and on significantly lower doses of immunosuppression than at the time of transplantation. This study demonstrates that urological complications constitute a major part of the morbidity after SPK transplantation. Despite this fact, appropriate treatment including enteric conversion can resolve most of the complications and prevent long-term morbidity or even graft loss.

Drainage↗
PubMed1993

A controlled, double-blind, randomized trial of verapamil and cyclosporine in cadaver renal transplant patients.

Calcium channel blockers have immunomodulating effects in vitro and may be effective in preventing cyclosporine nephrotoxicity. We studied the effect of verapamil following renal transplantation on the incidence of rejection and cyclosporine nephrotoxicity in a double-blind, placebo-controlled trial. Patients were randomly assigned to placebo (n = 28) or verapamil (n = 32) at doses of 80 mg twice a day. There was no difference in the incidence of rejection or cyclosporine toxicity in the two study arms. Recipients randomized to verapamil had lower mean cyclosporine doses at all intervals during a 1-year follow-up. Although cyclosporine doses were lower in the placebo group, the mean cyclosporine levels were equivalent in the two groups. Recipients in the verapamil-treated group had a higher mean serum creatinine at the end of the study--1.7 mg/dL versus 1.4 mg/dL in the placebo group. Actual 1-year graft survival was 89% for the placebo recipients versus 91% in the verapamil-treatment group. When compared with placebo, the concomitant use of low-dose verapamil results in lower cyclosporine doses but equivalent cyclosporine blood levels. Reduction in the incidence of rejection or cyclosporine nephrotoxicity were not observed.

Adult↗
PubMed1993

Urological complications in 210 consecutive simultaneous pancreas-kidney transplants with bladder drainage.

OBJECTIVE: The urological complications of 210 patients who underwent simultaneous pancreas-kidney (SPK) transplantation over a 7-year period were reviewed. SUMMARY BACKGROUND DATA: Worldwide, bladder drainage has become the accepted method of exocrine drainage after pancreas transplantation. With the increasing use of bladder drainage, the surgical post-transplant complications have shifted from intra-abdominal complications to urological complications. METHODS: Two hundred ten diabetic patients received SPK transplants with bladder drainage. A retrospective review was conducted to analyze the incidence, type, and management of urological complications. RESULTS: The most frequent urological complications were hematuria, leak from the duodenal segment, recurrent urinary tract infections, urethritis, and ureteral stricture and disruption. Complications related to the renal transplant included ureteral stricture and leaks, as well as lymphoceles. CONCLUSIONS: Despite the high incidence of urological complications, 5-year actuarial patient and graft survival are excellent. Only one graft and one patient were lost secondary to urological complications.

Adult↗
PubMed1993

Risk factors for primary dysfunction after liver transplantation--a multivariate analysis.

In a retrospective analysis on 323 orthotopic liver transplant procedures performed between July 1984 and October 1991 the incidence of two forms of primary dysfunction (PDF) of the liver: primary nonfunction (PNF), and initial poor function (IPF) were studied. The incidence of PDF was 22% (73/323) with 6% PNF (20/323) and 16% IPF (53/323), while 78% (250/323) had immediate function (IF). Occurrence of both IPF and PNF resulted in a higher graft failure rate (P < 0.001), retransplantation rate (P < 0.001), and patient mortality (P < 0.003) within the first three months after OLTx. Univariate analyses of donor and recipient factors and their influence on PDF demonstrated that longer donor hospitalization (> 3 days), older donor age (> 49 years), extended preservation times (> 18 hr), and fatty changes in the donor liver biopsy, as well as reduced-size livers, younger recipient age, and renal insufficiency prior to OLTx, significantly affected the incidence of IPF and PNF. Multivariate analysis of potential risk factors showed that reduced-size liver (P = 0.0001), fatty changes on donor liver biopsy (P = 0.001), older donor age (P = 0.009), retransplantation (P = 0.01), renal insufficiency (P = 0.02), and prolonged cold ischemia times (P = 0.02) were independently associated with a higher incidence of IPF and PNF. No statistical correlation was found between PDF and etiology of ESLD, nutritional status of the recipient, UNOS status, and Child-Pugh classification in this study. We conclude that PNF and IPF are both separate clinical entities that have a significant effect on outcome after OLTx. Routine donor liver biopsies are recommended to decrease the rate of IPF and PNF. The combination of risk factors shown to be significant for PDF should be avoided--and, if that is not possible, the only variable that can be controlled, the preservation time, should be kept as short as possible.

Adolescent↗
PubMed1993

Retransplantation of the liver--a seven-year experience.

Three hundred and four patients underwent 362 liver transplants between July 1984 and April 1992. Fifty-eight retransplants were performed in 44 patients (14.5%). Thirty-four patients underwent two (77.3%), seven patients three (15.9%), two patients four (4.5%), and one patient five (2.3%) transplants. Poor function accounted for 23 retransplants (6.4%), technical problems for 19 retransplants (5.2%), and rejection for 15 retransplants (4.1%). One-month patient survivals after retransplantation for poor function, technical problems, or rejection were similar (79.0%, 73.4%, and 80.0%, respectively). No difference in retransplantation rates were seen between adults and children receiving whole liver transplants (WLT) (11.6% versus 19.1%). However, retransplantation for poor function was more common in pediatric recipients receiving reduced-size liver transplants (RLT) (20.0% versus 0.0%, P < 0.01), while retransplantation for hepatic artery thrombosis (HAT) was more common in pediatric recipients receiving WLT (16.7% versus 2.8%, P < 0.05). The presence of multiorgan system failure of greater than four was associated with a high mortality (90%), whereas patients undergoing emergent retransplantation who had less than four systems fail had a survival of 73.9% and patients who underwent elective retransplantation had a survival rate of 81.8%. Length of stay and cost of liver transplantation was higher in patients undergoing retransplantation when compared with primary transplants (29.7 +/- 14.9 days versus 58.4 +/- 38.9 days and $122,358 +/- 59,782 versus $289,302 +/- 126,907, P < 0.01). The overall actuarial one-year patient survival in primary transplants was 86.6% and in retransplants 74.8%, and at five years these were 71.4% versus 62.5%, respectively (P < 0.05). Our results support continued retransplantation of the liver unless the patient's medical condition dictates otherwise.

Adolescent↗
PubMed1993

Renal transplantation at the University of Wisconsin in the cyclosporine era.

1. Immunological graft loss in the cyclosporine (CsA) era has been decreasing over the past decade with current 94% immunological graft survival at one year. 2. The rates of both immunological graft loss and graft loss from all causes gradually decrease after the first year for primary transplants. This implies that rejection gradually becomes less likely between one and 10 years follow-up. 3. On CsA immunosuppression, better DR matching results in significantly less immunological graft loss and a slower rate of late graft loss. 4. Roughly equal proportions of cadaveric renal transplants are lost due to acute rejection, chronic rejection, and death with a functioning graft (25-30% each). 5. Improving immunological graft outcome correlates with a lower incidence of a first rejection episode. Although OKT3 increases the success of rejection treatment, having a rejection episode nevertheless increases one's risk of immunological graft loss. 6. Cardiovascular deaths are by far the leading cause of mortality (42%) in this series. Improved strategies of prevention and treatment of cardiovascular disease are needed in this patient group. 7. Long-term CsA immunosuppression usually is not associated with graft loss due to CsA toxicity. Late graft loss from acute and chronic rejection is far more common, implying the need for continued immunosuppression even in patients with long-surviving grafts. 8. There is no measurable benefit of 3 or more random blood transfusions prior to cadaveric renal transplantation in the CsA era.

Academic Medical Centers↗
PubMed1993

Histocompatibility and liver transplantation.

BACKGROUND: The role of histocompatibility between donor and recipient in liver transplant rejection is unclear because of a paucity of data. The influence of human leukocyte antigen (HLA) type on immunologic graft loss was examined for primary liver transplantations performed at this center. METHODS: Immunologic graft loss included patient death or retransplantation as a result of rejection or impending graft loss caused by either late hepatic artery thrombosis or severe, unremitting rejection requiring FK 506 rescue therapy. HLA A, B, and DR matching was available on 205 donor-recipient combinations, and an additional 31 patients had A and B matching only. RESULTS: A mismatch of class I antigens (HLA A and B) was predictive of immunologic graft loss (p = 0.018). DR mismatch did not correlate with graft loss. When the A and B loci were analyzed separately, an A mismatch correlated significantly with immunologic graft loss (p = 0.02), in contrast to a B mismatch (p = 0.17). Better matching significantly improved patient survival (p = 0.02) and overall graft survival (p = 0.009). CONCLUSIONS: The beneficial effect of HLA class I antigen compatibility on liver transplantation outcome is in contrast to pancreatic and kidney transplantation in which class II antigen matching but not class I matching is beneficial. Immunologic mechanisms of hepatic allograft rejection may differ from those involved in kidney transplant rejection.

Forecasting↗
PubMed1993

Long-term results of liver transplantation for biliary atresia.

BACKGROUND: Biliary atresia can be treated by portoenterostomy, which is primarily palliative, or by liver transplantation, which is primarily curative. The purpose of this study was to determine the long-term outcome of liver transplantation for the treatment of biliary atresia. METHODS: During an 8-year period, 45 patients who underwent liver transplantation for biliary atresia and 10 patients who were referred to our center for portoenterostomy were retrospectively analyzed. RESULTS: No patient with biliary atresia died awaiting liver transplantation. The waiting time for all patients was 36.7 +/- 42.8 days. Thirty-four patients (75.6%) required one transplant, whereas 11 patients (24.4%) required 17 retransplants. Twenty-two patients (48.9%) required 39 reoperations (1.8 per patient). There were 4.9 infectious episodes, 2.2 rejection episodes, and 4.4 readmissions per patient. However, 91% of reoperations, 80% of infections, and 78% of rejections occurred within 6 months of transplantation. The overall 7-year actuarial patient and graft survival for patients with biliary atresia was 86.2% and 62.7%, respectively. CONCLUSIONS: Our results indicate that long-term patient survival after liver transplantation for biliary atresia is excellent. However, portoenterostomy continues to have an initial complementary but limited long-term role in the treatment of infants with biliary atresia.

Biliary Atresia↗
PubMed1993

Two hundred consecutive simultaneous pancreas-kidney transplants with bladder drainage.

BACKGROUND: Since 1982, 288 pancreas transplantations have been performed at the University of Wisconsin. This report reviews our experience with 200 consecutive simultaneous pancreas-kidney (SPK) transplantations during a 7-year period. METHODS: Two hundred consecutive SPK transplantations were performed between December 1985 to October 1992. Immediate posttransplant function and surgical and infectious complications were evaluated. Frequency of rejection episodes were analyzed, as was 5-year patient and graft survival. RESULTS: All but four pancreas transplants functioned immediately after transplantation. Three pancreas transplants failed because of thrombosis and one from primary nonfunction. Five-year patient survival was 90.2%, kidney survival 80.3%, and pancreas survival 78.6%. There were 54 surgical complications. Fifteen patients have died since 1985. The most frequent cause of death was infection (three patients). A total of 678 infectious episodes were recorded. Urinary tract infection (n = 344) was the most frequent type of infection. Enteric conversion was necessary in 35 patients, with the most frequent indication being a leak of the duodenal segment. CONCLUSIONS: We concluded from this series that SPK transplantation is associated with higher cost and morbidity as compared with kidney transplantation alone. However, excellent long-term survival in combination with the clearly demonstrated benefits for secondary diabetic complications indicate that SPK transplantation is the procedure of choice for carefully selected patients with diabetes.

Adolescent↗