David J. Effeney

Cold Storage Preservation and Warm Ischaemic Injury to Isolated Arterial Segments: Endothelial Cell Injury

Injury to endothelial cells is thought to be important to the development of the vascular lesion of chronic rejection. It was the aim of this study to develop a semiquantitative method to assess endothelial injury in arterial grafts and to document the injury produced by cold storage preservation and additional warm ischaemia. Twelve‐  and 24‐h cold preservation of rat aortic segments, together with an additional 1 h of warm ischaemia, were assessed. Electron micrographs of representative endothelial cells were scored for cytoplasmic, nuclear and mitochondrial injury. The overall injury score was obtained by addition of the individual scores. Storage for up to 24 h in University of Wisconsin (UW) and Terasaki did not produce any injury. Twenty‐four hours of storage in Euro‐Collins resulted in endothelial cell death. Injury occurred after 12 h of storage in Ross, Collins and normal saline, and the injury increased following 24 h of storage. One hour of warm ischaemia did not increase the injury. Injury to endothelial cells varies with the preservation solution used and the time of cold storage, so that both the type of solution and the storage time should be taken into account in clinical studies looking at the influence of cold ischaemia time and graft outcome.

Endothelium during microarterial graft procurement and transplantation

Microarterial grafts are prone to mechanical endothelial injury that can have profound effects on the transplanted vessel, a factor neglected in studies on vascular changes post‐transplantation. The aim of this study was to document the integrity of the endothelial lining after both procurement and transplantation of rat aortic grafts, using a minimal touch technique with and without the use of topical papaverine. It was found that procurement using a simple minimal touch technique preserved the endothelium and transplantation could be performed without endothelial injury. The appearance of “normal” endothelium varied with the degree of distension of the artery, suggesting a dynamic endothelial architecture to accommodate changes in the surface area of the artery during pulsation. These findings indicate that transplantation of an arterial segment without injury to the intima is possible and stress the importance of technical controls after both procurement and transplantation to prevent the use of injured grafts and misleading results.

Creation of a carotid-jugular fistula for repeated hemoaccess in a canine model

We have developed a method to obtain access to the arterial circulation in the dog, which can be used for repeated hemoperfusion, hemodialysis, and for pharmacokinetic studies. Hemoaccess is achieved by the surgical creation of a carotid-jugular fistula. Using the fistula, which is internal and autogenous, has overcome the problems of thrombosis, dislodgement, and infection, which are associated with external shunts. Blood flow rates of between 70 and 100 ml/min in 12-kg dogs were obtained through a hemodialysis pump. The surgical techniques are described in detail so that other investigators can avail themselves of the methodology.