Effect of Indomethacin on Peripheral Tissue Perfusion After Coronary Artery Bypass Surgery

The effect of indomethacin on peripheral tissue perfusion in the early phase after coronary artery bypass grafting (CABG) was investigated in ten patients randomly allocated to receive indomethacin 25 mg i.v. or placebo 'double-blind'. The patients were coupled to a respirator with FiO2 30 v/v %. Central haemodynamics, intrapulmonary shunt and blood gases showed no significant change in either group during the 2-hour study period. The thromboxane A2 metabolite P-TXB2 decreased significantly (p less than 0.05) in the indomethacin group, but the prostacyclin metabolite P-6-K PGF1 alpha showed no significant change in either group. The PtcO2 index (transcutaneous oxygen tension/arterial PO2), measured in the upper extremity, rose (p less than 0.05) after indomethacin infusion, but was almost unchanged in the controls. The mean subcutaneous tissue oxygen tension and the laser-Doppler skin red-cell flux underwent no significant change. The data thus suggested that indomethacin administered intravenously post-CABG may exert beneficial effects on peripheral tissue perfusion and oxygenation, possibly mediated by improvements in prostacyclin-thromboxane balance and microcirculation.