INFLUENCE OF LOW-DOSE ALLOPURINOL ON ISCHEMIA - REPERFUSION INJURY DURING ABDOMINAL AORTIC-SURGERY

Objectives: To ascertain whether surgery causes ischaemia-reperfusion (I-R) related injury, if this injury is augmented by preoperative shock, and reduced with low dose allopurinol. Design: Randomised blind placebo controlled trial. Setting: Surgical laboratory. Material and methods: 22 pigs were randomly allocated to four groups; OP = operation/placebo, OA = operation/allopurinol, SOP = shock + operation/placebo, SOA = shock + operation/allopurinol. An aortic tube prosthesis was inserted in all. In groups SOP and SOA preoperative shock was induced by exsanguination. Allopurinol was adminstered in group OA on the preoperative day and peroperatively, in group SOA during shock and peroperatively. Chief outcome measures: Perioperative blood concentrations of thiobarbituric acid reactive species (TEARS), ascorbic acid (AA), albumin, Tc-99m-albumin and creatine phosphokinase (CPK) as indicators of oxidative membrane damage, antioxidant activity, microvascular permeability changes and muscular cell damage respectively. Main results: In the OP and OA groups TBARS gradually increased, while AA, Tc-99m-albumin and CPK remained unchanged and albumin decreased. No effect of allopurinol was observed in these groups. In the SOP group TBARS and AA were not significantly different from groups OP and OA. Yet, albumin, Tc-99m-albumin and CPK decreased significantly more in the SOP group. Compared with the SOP group, allopurinol treatment (SOA) produced lower TEARS and higher AA levels, and reduced the effect of shock on albumin, Tc-99m-albumin and CPK concentrations. Conclusion: Aortic surgery causes no I-X related damage. Pre-operative shock produces I-R related damage, which is reduced by allopurinol.