Biomedical subjects

D Manas

Publications and source records attributed to D Manas.

At least 19 recordsLinked to original sources

PubMed2006

Agonal period in potential non-heart-beating donors.

The shortage of donor kidneys for renal transplantation is becoming more severe as the gap between the number of patients waiting for renal transplantation and the number of cadaveric organs available continues to widen. Therefore, many centres have started using non-heart-beating (NHB) donors. There was no clear plan for maximal duration of agonal period in Maastricht category NHB donors after withdrawal of treatment in Newcastle. This withdrawal has been audited in retrospect. Our current wait time is now a maximum of 5 hours; however, previously there have been some considerably longer periods. Concern has always been expressed about poor quality with protracted periods. Nonuse in this review of 58 kidneys can be expressed against time: 0 to 2 hours 13%, 2 to 5 hours 33%, and >5 hours 45%. Therefore, though the nonuse rate was significantly different between 0 to 2 hours and >5 hours (P < .05, chi-square), there were 16 transplants performed with kidneys >2 hours and 12 transplanted >5 hours. In conclusion, although good usable kidneys can still be used with protracted withdrawal, there are considerable logistical difficulties with our 5-hour cut-off, which means that one third of potential kidneys will not be utilized.

Heart Arrest↗

PubMed2006

Dual renal transplantation for kidneys from marginal non-heart-beating donors.

Kidneys transplanted from non-heart-beating donors (NHBD) are generally regarded as marginal or extended criteria grafts due to the associated period of warm ischemia. The most prolonged periods occurring in the category II (uncontrolled) donor. This potential for injury can adversely affect the glomular filtration rate (GFR), which in severe cases results in primary nonfunction. Viability testing can identify a group of kidneys that, although unsuitable for solitary transplantation, may be considered for dual transplant. This retrospective study examined a series of 11 dual renal transplants, comparing 3- and 12-month GFR outcome data with 81 single NHBD transplants. The mean GFR at 3 months in the dual group was 47.6 and at 12 months was 48.6. In the single group the GFR at 3 months was 40.6 and at 12 months was 41.9. Thus using viability testing to identify NHBD kidneys suitable for dual transplant appears reliable and predictable.

Follow-Up Studies↗

PubMed2006

Renal transplants from category III non-heart-beating donors with evidence of pre-arrest acute renal failure.

Kidneys transplanted from non-heart-beating donors (NHBDs) have been exposed to varying degrees of ischemic damage after death. Category III donors have invariably been managed, treated, and investigated in a hospital setting prior to arrest and death. Some therefore exhibit evidence of renal dysfunction and even acute renal failure (ARF) before death. Many surgeons would regard a NHBD with pre-arrest evidence of ARF as too marginal for renal transplantation. This retrospective study examines five Maastricht category III NHBD donors with evidence of pre-arrest ARF. We compare 3- and 12-month GFR outcome data from the nine resulting transplants with 40 category III NHBD transplants with normal pre-arrest renal function. The mean GFR at 3 months was 45.4 and 43.8 for the ARF and normal group, respectively. At 12 months the GFR was 42.2 and 44.7 in the ARF and normal groups, respectively. Thus evidence of ARF pre-arrest does not preclude successful category III NHBD renal transplantation.

Acute Kidney Injury↗

PubMed2006

Predisposing factors for biliary complications following liver transplantation.

INTRODUCTION: Biliary complications remain a major cause of morbidity and mortality in patients following liver transplantation. We sought to identify possible risk factors predisposing to biliary complications after OLT using duct-to-duct biliary reconstruction. MATERIALS AND METHODS: We retrospectively reviewed 5 years of prospectively collected donor and recipient data between April 1999 and April 2004. We evaluated the presence of biliary complications, donor and recipient age, cold ischemia time, hepatic artery thrombosis, non-heart-beating donor (NHBD), and graft steatosis (>30%). The results were compared with a control group of OLT patients without biliary complications. RESULTS: Among 173 OLT recipients, biliary complications occurred in 28 patients (16.2%), of whom 12 were leaks, 15 strictures, and 1 a nonanastomotic intrahepatic stricture. The mortality following biliary complications was 11%, compared to 6% in the control group. CONCLUSION: Biliary complications remain a persistent problem in OLT. Analysis of risk factors identified hepatic artery thrombosis and steatosis as predisposing factors. With greater experience, NHBD livers may also prove to be at greater risk of biliary complications.

Adult↗

PubMed2006

Diabetic donors as a source of non-heart-beating renal transplants.

Due to the organ shortage, many renal transplantation centers attempt to increase the donor pool by using non-heart-beating donors (NHBDs). These kidneys are generally regarded as "marginal" grafts. Many centers do not consider transplantation from an NHBD with a history of diabetes as it is a more suboptimal donor. We began our NHBD program in 1998 and have performed 5 renal transplants from diabetic NHBDs. Viability testing identified kidneys suitable for single or dual transplantation. Although kidneys from brain stem dead donors with diabetes have been used successfully, our data suggested that kidneys from diabetic NHBDs can also be used although we still need long-term results.

Cadaver↗

PubMed2006

Renal graft function after prolonged agonal time in non-heart-beating donors.

To deal with the increasing gap between organ demand and supply for kidney transplantation, many centers have started to use non-heart-beating (NHB) donors. When we initiated our program to utilize kidneys from such donors in 1998, we had no protocol for the maximal agonal period. This however was audited in retrospect. Our current wait time is now a maximum of 5 hours. Concern has been expressed in the past about possible deterioration in the quality of the organs with a protracted agonal time. We aimed in this study to examine the effect of prolonging agonal period on the quality of kidneys retrieved from Maastricht category III donors: A total of 40 kidneys were transplanted from 29 category III donors between 1998 and 2004. Eleven kidneys had donor agonal times of >5 hours; the remainder, agonal times <5 hours. Both groups were matched for donor and recipient factors. The mean glomerular filtration rates at 12 months for <5 hours versus >5 hours agonal time were 43.8 +/- 4.4 versus 49.8 +/- 5.8, respectively (P = .24) and at 24 months, 46.83 +/- 8.99 versus 37.67 +/- 3.85, respectively (P = .24). In conclusion, intermediate graft function is comparable to ones with shorter agonal time, although we await long-term results.

Adult↗

PubMed2006

Non-heart-beating kidney transplantation: 6-year outcomes.

Non-heart-beating donor kidneys (NHBD) are being used to increase the donor pool due to the scarcity of cadaveric heart beating donors (HBD). We evaluated the long-term outcomes of renal transplantation using NHBD kidneys, comparing the first 100 NHBD kidneys transplanted at our facility to the next consecutive cadaveric HBD kidneys for graft survival, recipient survival, and quality of graft function. Recipient survival (P = .22) and graft survival (P = .19) at 6 years did not differ between recipients of NHBD (83%, 80%) and HBD (89%, 87%) kidneys. Quality of graft function using the mean glomular filtration rates were significantly lower in the NHBD group up to 3 months following discharge (41 +/- 2 vs 47 +/- 2, P = .007) but were then comparable up to 6 years following transplantation (43 +/- 5 vs 46 +/- 4, P = .55).

Adolescent↗

PubMed2005

Management of hilar cholangiocarcinoma in the North of England: pathology, treatment, and outcome.

AIM: To assess the management and outcome of hilar cholangiocarcinoma (Klatskin tumor) in a single tertiary referral center. METHODS: The notes of all patients with a diagnosis of hilar cholangiocarcinoma referred to our unit for over an 8-year period were identified and retrospectively reviewed. Presentation, management and outcome were assessed. RESULTS: Seventy-five patients were identified. The median age was 64 years (range 34-84 years). Male to female ratio was 1:1. Eighty-nine percent of patients presented with jaundice. Most patients referred were under Bismuth classification 3a, 3b or 4. Seventy patients required biliary drainage, 65 patients required 152 percutaneous drainage procedures, and 25 had other complications. Forty-one patients had 51 endoscopic drainage procedures performed (15 failed). Of these, 36 subsequently required percutaneous drainage. The median number of drainage procedures for all patients was three, 18 patients underwent resection (24%), nine had major complications and three died post-operatively. The 5-year survival rate was 4.2% for all patients, 21% for resected patients and 0% for those who did not undergo resection (P = 0.0021). The median number of admissions after diagnosis in resected patients was two and three in non-resected patients (P<0.05). Twelve patients had external-beam radiotherapy, seven brachytherapy, and eight chemotherapy. There was no significant benefit in terms of survival (P = 0.46) or hospital admissions. CONCLUSION: Resection increases survival but carries the risk of significant morbidity and mortality. Percutaneous biliary drainage is almost always necessary and endoscopic drainage should be avoided if possible.

Adult↗

PubMed2005

A simple cardiovascular risk score can predict poor outcome in non-heart-beating donor renal transplantation.

A simple cardiovascular risk score used in our centre to plan cardiovascular work-up for renal transplantation can predict outcome in non-heart-beating donor (NHBD) renal transplantation. Patients in the higher-risk group, with a score of >12 of a maximum of 36 are likely to have a longer duration of delayed graft function, poorer glomerular filtration rate at 6 months, and inferior graft and patient survival, together with a relative rate of graft loss within 60 days of 4.514 (P = .019) and within 1 year of 3.511 (P = .036). Although a high cardiovascular risk score should not be regarded as a contraindication to NHBD transplantation, the score can be used to facilitate recipient selection.

Adult↗

PubMed2005

Does donor cardiopulmonary resuscitation time affect outcome in uncontrolled non-heart-beating donor renal transplants?

Uncontrolled non-heart-beating donors offer the opportunity to significantly expand the potential pool of kidney donors but are associated with a variable duration of cardiopulmonary resuscitation (CPR), where cardiac output is only 30% to 40% of normal. We were concerned that prolonged CPR would adversely affect the function of transplanted kidneys. In our series of 46 uncontrolled donors the mean duration of CPR was 60 minutes, which also represents a realistic cutoff point for CPR duration. Taking a cutoff point of 60 minutes, we found no differences in kidney discard rates following viability assessment, primary nonfunction rate, or duration of delayed graft function. We therefore conclude that if formal viability assessment is performed, kidneys may be retrieved from uncontrolled non-heart-beating donors irrespective of duration of CPR.

Cardiac Output↗

PubMed2005

Variation in organ donation in northeastern England 1986 to 2003.

Renal transplantation is established as the best form of renal replacement therapy, but demand for kidneys exceeds supply from cadaveric donations. It is therefore important to make the best use of the pool of potential cadaveric organ donors. Donation rates are to a large extent dependent on public opinions, which may be influenced by external events. In northeast England from 1986 to 2003, there was a potential pool of 1170 brain stem-dead donors, of whom 190 (16%) could not be retrieved due to relatives' objections. From 1998 to 2003 we were referred 90 potential non-heart-beating donors, of whom relatives refused donation in 10 (11%). A major reason for not retrieving organs from a potential donor has been lack of consent from the relatives. Refusals appear to vary year by year and are consistently lower for non-heart-beating donors. This therefore raises the possibility that negative or positive media publicity plays a role in this variation.

Attitude to Death↗

PubMed2005

A simple cardiovascular risk score can predict poor outcome in NHBD renal transplantation.

A simple cardiovascular risk score used in our center to plan cardiovascular workup for renal transplantation can predict outcome in non-heart-beating donor (NHBD) renal transplantation. Patients in the higher risk group, with a score of >12 out of a maximum of 36 are likely to have a longer duration of delayed graft function, poorer glomerular filtration rate at 6 months, and inferior graft and patient survival, together with an relative rate of graft loss within 60 days of >4 (P = .053). Although a high cardiovascular risk score should not be regarded as a contraindication to NHBD transplantation, the score can be used to facilitate recipient selection.

Adult↗

PubMed2003