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E B Edwards

Publications and source records attributed to E B Edwards.

29 records · Page 2Linked to original sources
PubMed1996

When perfectly HLA-matched kidneys are refused for transplant: implications for a national cooperative sharing system.

BACKGROUND: The transplant community attempts to maximize overall renal graft survival rates through nationwide sharing of perfectly-matched cadaveric kidneys. Although the number of such transplants is determined annually, the number available but not transplanted has never been assessed. There has also been no verification of the widespread claim that kidneys transplanted as paybacks for perfect matches are inferior. STUDY DESIGN: From records of the United Network for Organ Sharing, a complete accounting of six-antigen-matched kidney disposition was obtained, including a frequency distribution of reasons for refusal given when kidneys were refused for matched patients. Actuarial graft survival (GS) rates for matched, payback, and other cadaveric renal transplants were determined. RESULTS: Of the six-antigen-matched kidneys available, 97 percent were transplanted; 71 percent of those were accepted for matched patients. The two-year GS rate for matched patients was 84 percent, significantly higher than that for kidneys available for matched patients but transplanted into other patients (71.3 percent) and that for all other cadaveric kidneys (75.5 percent). Most reasons for refusal were related to donor quality. Kidneys refused for such reasons showed a 67.7 percent two-year GS rate in nonmatched patients and the highest rates of acute and chronic rejection and primary failure. The two-year GS rate for kidneys accepted as paybacks for matched kidneys (75.7 percent) was equivalent to that for all non-matched cadaveric kidneys (75.5 percent). CONCLUSIONS: If all normal-quality grafts refused for perfectly matched patients during 1990 through 1992 had been accepted for those patients, the number of transplants with typically superior survival rates could have increased by 25 percent, from 1,365 to 1,704. The payback requirement of the United Network for Organ Sharing does not seem to reduce the overall benefits of sharing perfectly matched kidneys nationwide.

Cadaver↗
PubMed1994

The effect of transplant center volume on cardiac transplant outcome. A report of the United Network for Organ Sharing Scientific Registry.

OBJECTIVE: The number of cardiac transplant programs continues to increase despite no increase in the number of hearts available for transplantation. As a result, the majority of heart transplant centers perform extremely small numbers of transplant operations annually. To determine the effect of small transplantation volume on transplant outcome, the following study was performed. DESIGN: Using the Scientific Registry of the United Network for Organ Sharing, all cardiac transplant procedures from October 1987 through December 1991 were analyzed to determine whether center volumes affected cardiac transplant outcome. Patient survival rates for each center were determined, and the survival rates were modeled for the following patient variables: first transplantation or retransplantation, patient condition at the time of transplantation, patient underlying cardiac disease (congenital vs all others), and time. SETTING: All cardiac transplant centers in the United States were included in the analysis. PATIENTS: All patients undergoing cardiac transplantation in the United States from October 1987 through December 1991 were included in the analysis. MAIN OUTCOME MEASURE: The primary end point in this analysis was mortality. RESULTS: Throughout the entire study, of the 150 cardiac transplant centers, 35.3% of the centers were performing fewer than five cardiac transplantations per year, 53.3% were performing fewer than nine transplantations per year, and 61.3% were performing fewer than 12 transplantations per year, the minimum required for Medicare payment eligibility. Using the modeled survival rates, the risk of mortality decreased to a basal level in those centers performing between eight and 10 transplant operations per year. In centers performing fewer than nine transplantations, mortality increased sharply and exponentially. Dividing centers into those that performed nine or more transplantations per year (70 centers) and fewer than nine transplantations per year (80 centers), the increased risk of mortality at 1 month and 12 months was 40.3% and 33.1%, respectively, in centers performing fewer than nine cardiac transplantations per year (P < .001). Once the threshold of nine transplant procedures was met, those centers that were eligible for Medicare payment did not have significantly better survival than those centers not eligible for Medicare coverage. CONCLUSIONS: These data demonstrate that the risk of mortality at early and intermediate time points is substantially higher in low-volume cardiac transplant centers, which make up more than half of the centers performing cardiac transplantation in the United States.

Adolescent↗
PubMed1993

The UNOS OPTN waiting list from 1988 to 1993.

Based on data from the OPTN Waiting List and the Scientific Registry between 1988 and 1992: 1. On October 31, 1993 the combined waiting list for a solid organ transplant contained 32,603 registrations. This represents more than a 100% increase since 1988. Specifically, registrations for a lung transplant grew by more than 1600% and registrations for a liver transplant increased by 356% during the period. The intestine waiting list contained 900 registrations on October 31, 1993. 2. The distribution of patient characteristics on the waiting list snapshot as of October 31, 1993 was not markedly different from that on previous snapshots. Slight increases in the percentage of older (65 years) kidney, liver, and heart registrants were apparent. A slight decrease in the percentage of highly sensitized (PRA > or = 80%) kidney registrants was observed. 3. In general, median waiting times to transplant have increased each year between 1988 and 1992. During this period, the most significant increases were observed for kidney-pancreas registrants (277% increase) and lung registrants (205% increase). 4. For all waiting lists except heart-lung, registrants with blood type O waited substantially longer for a transplant than registrants with blood type A. This was especially true for kidney registrants. Other notable differences in waiting times on the kidney waiting list occurred between Blacks and Whites and between adults and pediatric registrants. Males waited on the heart waiting list for a transplant over twice as long as females. 5. The overall percentage of registrants who died while waiting for a transplant in 1992 was 5.8%, compared with 5.5% in 1988. The highest death rates occurred for thoracic registrants (13.1%, 16.2%, and 12.7% for heart, heart-lung, and lung, respectively). The lowest death rates occurred for kidney (3.5%) and kidney-pancreas registrants (1.2%). The death rate for pancreas registrants (9.4%) was greater than the death rate for liver registrants (8.5%). The number who died while waiting increased each year between 1988 and 1992, but the rate of increase may be declining.

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PubMed1992

The UNOS OPTN (Organ Procurement and Transplantation Network) waiting list: 1988 through November 30, 1992.

Based on data from the OPTN Waiting List and the Scientific Registry between 1988 and 1992: 1. The number of registrations on the overall waiting list increased by 81% between December 31, 1988 and November 30, 1992. On November 30, 1992, there were 29,047 registrations for a transplant in the United States. Organ-specific waiting lists showing strong increases during the period were lung (1,277%), liver (262%), and heart (162%). The number of heart-lung registrants decreased during the period. 2. Overall, Whites comprised the largest percentage of waiting-list registrants, followed by Blacks and Hispanics. This frequency distribution remained relatively constant between 1988 and 1991. On the organ-specific waiting lists, the percentage of Whites ranged from 80% on the liver waiting list to 90% on the pancreas waiting list. Blacks make up about 12% of the United States population, but about 32% of the kidney waiting list, due to the high incidence of end-stage renal disease among Blacks in the United States. 3. The frequency distribution of age on the waiting lists is shifting toward a greater proportion of potential recipients age 45 or older. This trend was especially true for the liver, lung, and pancreas waiting lists. 4. The percentage of highly sensitized registrants (PRA > or = 80%) on the kidney waiting list decreased by 8% between 1988 and 1991. The percentage of registrants with PRA less than 20% increased by 11.3%, probably as a result of longer waiting times for low-PRA registrants. 5. A result of the growth of the waiting lists was an increase in the median waiting time to transplant during the period. This effect was observed on every waiting list except the heart-lung. The wait for a liver transplant was the shortest (67 days in 1991), whereas the wait for a heart-lung transplant was the longest (543 days in 1990). 6. The overall death rate remained relatively stable, but was up slightly in 1991, when 6.1% of registrants died while waiting for a transplant (compared with 5.6% in 1990). The death rate on the heart-lung waiting list fell from 23.5% in 1988 to 14.8% in 1991, probably because of fewer heart-lung registrations. In 1991, the death rates were highest on the thoracic waiting lists (11.7-14.8%), followed by liver (9.3%), kidney (3.7%), and pancreas (3.0%). 7. The percentage of patients in the most urgent medical status categories remained stable on the heart waiting list and has decreased on the liver waiting list.

ABO Blood-Group System↗
PubMed1991

Liver transplantation in the United States: 1988 to 1990.

Between 1988 and 1990, the frequency of liver transplantation in the United States increased by 57%. During this same period, the number of transplant centers performing this procedure increased from 58 to 80. Despite this increase, only 15 centers reported a total of at least 100 procedures during these 3 years, compared to 25 centers that performed 12 or less liver transplantations. Recipient characteristics have been changing over time: a larger proportion of recipients were males in 1990 than in 1988 or 1989. The distribution of recipients changed dramatically; the median age increased by 4 years, due to an increased proportion of transplantations among those age 40 and older and a decrease in children younger then age 10. Another major change was in functional status; in 1988 and 1989, over half of the recipients were hospitalized while awaiting transplantation, but this was reversed in 1990, when the majority of patients was at home awaiting transplantation. Furthermore, the proportion of patients in the highest functional class more than tripled. Alcoholic liver disease, which in 1989 became the most common primary liver disease of patients undergoing liver transplantation, continues to be the indication for an increasing number of recipients. The proportion of recipients with biliary atresia and primary biliary cirrhosis, the most common diagnoses in 1988, continues to decrease. Most of the mortality was noted in the first 6 months, when overall cumulative patient mortality was about 20%, half of which occurred in the first 4 weeks after OLTX. The cumulative 3-year posttransplant survival rate was 67%. Similarly, cumulative retransplant-free survival rates were 84% at 1 month and 58% at 3 years. As previously described (1), recipient factors associated with survival included age, UNOS description, diagnosis, and ABO matching. Older recipients, those with poorer functional status at time of transplantation, recipients with either fulminant liver failure or malignancies, and those who received a graft from an ABO-compatible or -incompatible donor, had the worst survival rates. Furthermore, in the current analysis we found that the outcome of recipients was affected adversely by grafts from female donors. Racial differences were noted, but the large quantity of missing data precluded definitive statements regarding any association with survival. Both recipient and donor ages were significant prognostic factors. For adults in the multivariate model, increasing recipient age was associated with higher mortality. Among children, however, younger donor age seemed to have an adverse effect on recipient survival. Donor characteristics also changed during this period.(ABSTRACT TRUNCATED AT 400 WORDS)

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