OPERATIONS ON THE THORACIC AORTA AND HYPOTHERMIC CIRCULATORY ARREST -IS APROTININ SAFE

Introduction: The safety of aprotinin, especially when used with profo und hypothermic circulatory arrest, is still a matter of intense debat e despite its presumed salutary effects on blood loss, Many investigat ors have reported toxic renal effects of high-dose aprotinin in such p atients, but no prospective, randomized study has been conducted, To a ssess the potential detrimental effect of aprotinin on renal function and its putative reduction of blood loss, 50 patients undergoing thora cic aortic operations with the use of profound hypothermic circulatory arrest were randomly assigned to receive either low-dose aprotinin (1 x 10(6) kallikrein activation units) or placebo, Methods: The specifi c renal tubular markers beta-(2)-microglobulin and beta-N-acetyl-D-glu cosaminidase, as well as serum creatinine and blood urea nitrogen, cre atinine clearance, sodium excretion, and potassium excretion, were mea sured to evaluate renal function preoperatively, immediately after the procedure, and 24 hours and 48 hours later. Results: No statistically significant difference was found in any measured renal parameter betw een the two groups (analysis of variance), Renal dysfunction, defined as an elevation of serum creatinine early postoperatively (greater tha n or equal to 1.5 times the preoperative value), occurred in two patie nts who received aprotinin and in one patient in the control group. Te mporary dialysis (hemodialysis or continuous venovenous hemofiltration ) was needed in two patients in the aprotinin group versus one in the control group, furthermore, patients treated with aprotinin had signif icantly less total postoperative blood loss (718 +/- 340 ml vs 920 +/- 387 ml, p = 0.04). The aprotinin recipients also had a significantly lower transfusion requirement (p < 0.05), Conclusion: This controlled trial of low-dose aprotinin in patients undergoing thoracic aortic ope rations using profound hypothermic circulatory arrest demonstrated no detectable deleterious effects on renal function; moreover, the use of aprotinin was associated with significantly lower need for transfusio n.