Continuous flow registration for early detection of hepatic artery thrombosis after liver transplantation. Innovative technology reducing retransplantation rate?
04 / 2006 - unknown
Liver transplantation is the only life-saving treatment for patients with end-stage liver disease with 1-, and 5-year patient survival rates of 80 and 69%. About 7% of grafts are lost because of hepatic artery thrombosis (HAT). In those cases urgent retransplantation (ReTx)is the only option. ReTx is associated with increased morbidity and mortality and adds an extra burden to the shortage of donor organs. Screening for HAT is performed by intermittent Doppler transcutaneous ultrasound examinations. These are, however low in accuracy, time-consuming, operator dependent and not continuous. This lack of accuracy results in additional invasive investigations like (CT)angiography. The only possibility to rescue a liver graft with HAT is an urgent operative revascularisation. Currently the delay in diagnosis often precludes a succesful revascularisation resulting in graft loss and ReTx. - Objective: To measure accuracy of continuous flow registration (CFR) for early HAT detection. 1. describe the healthcare issue that underlies this proposal: Liver transplantation is an established treatment for patients with end-stage liver disease with a 5-year patient survival rate of 69%. One of the most frequent indications for early retransplantation (ReTx) is hepatic artery thrombosis (HAT). The reported incidence varies from 2-11% and is especially high in pediatric liver transplantation. HAT is characterized (initially) by a lack of symptoms and signs. Therefore all patients are screened for HAT in the first period after transplantation by performing Doppler ultrasound examinations. Logistics prohibit a more than once daily examination, which is already a time and cost intensive detection method. Aim of the study: To determine the accuracy of continuous flow measurement using an implantable Doppler ultrasound system for the detection of hepatic artery thrombosis in the early post-operative period in patients after liver transplantation. This accuracy will be tested using the current 'gold standard' protocol consisting of intermittent Doppler ultrasound examinations and/or (CT)angiographies. Retransplantation (ReTx) of the liver is associated with an increased risk of morbidity and mortality as compared to primary transplantation. Associated with the increased morbidity and mortality are a longer stay in the intensive care unit and the hospital, resulting in increased costs. Furthermore, retransplantation because of HAT detriments the already severe shortage of suitable donor organs which is the most important barrier for growth of transplant programs. The increased risk of mortality after ReTx results in an even greater loss of organs because not only the primary liver graft is lost but also the second graft has a lower chance of survival because of patient death due to other failing organs.