Protective effect of vasodilators in donors requiring pressor support

Renal dose dopamine given to organ donors improves renal blood flow and therefore should theoretically improve the quality of the renal grafts and increase the incidence of immediate graft function (IGF). Allografts which function immediately have a better long-term survival. Dopamine, in doses of less than 4 microg/kg per min, acts directly on receptors in blood vessel walls in the splanchnic bed causing vasodilation. In contrast, dopamine given at doses of greater than 4 microg/kg per min to hypotensive donors to elevate the systemic blood pressure has a direct adrenergic effect and causes vasoconstriction. This vasoconstriction when combined with the reperfusion injury which occurs after transplantation may jeopardize the chance of the graft functioning immediately. We studied 31 consecutive donors to see if those donors requiring pressor support (dopamine) to maintain systemic blood pressure had a lower incidence of IGF and whether this could be modified by giving the donor vasodilator drugs during procurement of the organs.