Controlled limb reperfusion in patients having cardiac operations

Severe limb ischemia in patients having cardiac operations may occur after intraaortic balloon pump insertion, prolonged femoral vessel cannulation, percutaneous cardiopulmonary bypass, dissecting aneurysms, or emboli. Normal blood reperfusion can cause a postischemic syndrome that increases morbidity and mortality. This clinical study is based on an experimental infrastructure patterned after controlled cardiac reperfusion. (1) It tests the hypothesis that controlled limb reperfusion (i.e., modifying the composition of the initial reperfusate and the conditions of reperfusion) reduces the local and systemic complications seen after normal blood reperfusion. (2) It reports initial clinical application of this strategy in three cardiac surgery centers.

Controlled limb reperfusion was applied to 19 patients with signs of severe prolonged unilateral or bilateral ischemia (including paralysis, anesthesia, and muscle contracture); six patients (32%) were in cardiogenic shock. The mean ischemic duration was 26 +/- 6 hours. The reperfusion method includes a 30-minute infusion into the distal vessels of a normothermic reperfusate solution mixed with the patient's arterial blood (obtained proximal to the obstruction) in a 6:1 blood/reperfusate ratio. Data are mean +/- standard error of the mean.

Sixteen patients (84%) survived with salvaged and functional limbs at the time of discharge. No renal, cardiac, pulmonary, cerebral, or hemodynamic complications developed in the survivors. The three deaths occurred in patients undergoing controlled limb reperfusion while in profound postoperative cardiogenic shock; neither postischemic edema nor contracture developed in any of them.

These findings show that controlled limb reperfusion can be applied readily with standard equipment that is used for cardiac surgery and may salvage limbs while reducing postreperfusion morbidity and mortality.