Delayed graft function (DGF) after kidney transplant is associated with long-term allograft dysfunction. Niemann et al. (NEJM 2015;373:405) reported that therapeutic hypothermia reduced DGF (defined here as the requirement of dialysis in the recipient within 7 days after renal transplantation).
Study group enrolled 370 kidney donors after neurological determination of death (DNDDs), randomized to either normothermia (36.5 to 37.5 deg., n= 280) vs. mild hypothermia (34-35 deg. either by allowing to spontaneously reach the temperature, or by passive-cooling devices or forced-air systems, n=286). Incidence of DGF was significantly lower in hypothermia group (28.2% vs 39.2%, p=0.008), and study was terminated early.
Therapeutic hypothermia (targeted temperature management) is an established intervention for outside-hospital cardiac arrest to protect neurological function.
In transplant field, in contrast, current organ procurement protocol (e.g. one from NATCO) has a stipulation that normal body temperature should be maintained in donors, frequently requiring active warming with warm blankets.
What is the protective mechanism? Authors discussed possible contribution of ischemia-reperfusion injury. Is this procedure applicable to other organs? Many questions arise and there is a nice open forum with NEJM group to discuss these (til August 7th EDT).
Naoka Murakami, MD PhD