Studies of Reperfusion Injury in Skeletal Muscle: Controlled Limb Reperfusion to Reduce Post-Ischaemic Syndrome

Abstract

Revascularization after prolonged complete limb ischaemia may result in both severe damage to skeletal muscle and various systemic manifestations of the postischaemic syndrome. Previous experimental studies performed by the authors have shown that these are caused, to a large extent, by normal reperfusion at normal systemic pressure and that this additional injury can be substantially reduced by controlled reperfusion of the revascularized limb before restoration of the normal circulation. This treatment includes control of the conditions of reperfusion and composition of the initial reperfusate. In the present study, this concept of controlled limb reperfusion was applied to patients with prolonged severe lower limb ischaemia. Controlled limb reperfusion was used in 11 patients after prolonged complete unilateral or bilateral ischaemia. The ischaemic interval ranged from 5 to 21 h. Two patients were in cardiogenic shock, ten had a history of associated cardiac disease and seven coexistent peripheral vascular disease. After systemic heparinization, thromboembolectomy was undertaken using a Fogarty catheter. Cannulas were placed in the iliac, profunda and superficial femoral arteries and connected to a reperfusion set. Oxygenated blood was drawn from the iliac artery and mixed with an asanguineous solution (ratio 6:1). This controlled reperfusate was returned to the profunda and superficial femoral arteries using a single roller pump. The system allows control of both the composition of the reperfusate (Ca²⁺, pH, osmolarity, glucose, substrate, P _O2, free radical scavengers) and the conditions of reperfusion (pressure, flow, temperature). After 30 min of controlled limb reperfusion, the cannulas were removed, the arteriotomy closed and normal blood reperfusion started. All nine patients who were haemodynamically stable before operation survived the procedure and were discharged with full functional recovery, including one patient with acute aortic occlusion of several hours' duration. Thus controlled limb reperfusion avoided the need for amputation and the development of systemic complications. Two patients, who were in cardiogenic shock before operation, died from progressive cardiac failure. It is concluded that controlled arterioarterial limb reperfusion may reduce the local manifestation of the postischaemic syndrome after prolonged periods of ischaemia, salvage limbs thought to be irreversibly damaged by prolonged ischaemia and is easily performed in the operating room.