Effect of propofol on reperfusion injury after regional ischaemia in the isolated rat heart

Free oxygen radicals and intracellular calcium homeostasis play importantroles in the development of myocardial reperfusion injury. Propofol is aradical scavenger with calcium channel blocking properties. We haveinvestigated the effects of propofol on myocardial reperfusion injury. Weused an isolated rat heart model where heart rate, ventricular volume andperfusion pressure were constant. The left anterior descending coronaryartery (LAD) was occluded for 30 min and reperfused for 2 h. We studied anuntreated control group, an Intralipid group (1 microliter ml-1) and apropofol group (Intralipid 1 microliter ml-1 and propofol 1 microgram ml-1)(n = 12 each). Drugs were infused for 20 min starting 5 min beforereperfusion. We measured left ventricular developed pressure (LVDP),coronary flow and infarct size. LAD occlusion reduced mean LVDP from 129(SEM 4) to 36 (3) mm Hg and mean coronary flow from 12.2 (0.3) to 5.2 (0.2)ml min-1. During reperfusion, LVDP recovered to 98 (4) mm Hg and coronaryflow to 11.9 (0.4) ml min-1. Haemodynamic variables were similar in allgroups. Propofol had no effect on infarct size compared with the Intralipidgroup (25.0 (3.7) vs 26.9 (3.3)% of the area at risk; P = 0.89). Infarctsize in the Intralipid group tended to be smaller compared with the controlgroup (34.8 (3.2)%; P = 0.19). We conclude that propofol, at a clinicallyrelevant concentration, provided no protective effect against myocardialreperfusion injury in the rat heart in vitro.