Assessment of vascular function of hand allografts

Insufficiency of blood vessels supplying a limb allograft may lead to loss of the extremity. Thus, a regular evaluation of perfusion of transplants seems a reasonable approach. The purpose of the present study was assessment of allograft perfusion by means of non-invasive methods.

Six hand allografts transplanted in 5 patients were included in the study group. The transplant procedure occurred on average 45 months before. The study group comprised 2 allografts at forearm level, 2 transplants of the arm, and 1 bilateral transplant of the forearm. Parameters of blood flow using Doppler ultrasonography, impedance plethysmography, Doppler measurement of segmental pressures, optical pulse oscillography (OPO), and thermography were performed in all participants.

DUS revealed increased resistive index in ulnar arteries of transplant hands compared to native hands and an altered blood supply was confirmed by IP. Flow-mediated dilatation within the transplanted extremity was abnormal in most patients and was inversely correlated with number of episodes of acute rejection. Analysis of oscillographic spectrum revealed flattening of the dicrotic notch in transplant hands. A tendency for lower temperature of the skin of transplanted hands compared to native extremities was also observed.

In asymptomatic patients after limb transplantation, non-invasive methods disclosed discreet abnormalities of graft perfusion. Thus, regular measurement of perfusion parameters using these methods appears to be a promising approach to detect early and potentially reversible disturbances of blood supply. Further observational studies are required to determine its clinical significance.