Cardioprotection by sevoflurane against reperfusion injury after cardioplegic arrest in the rat is independent of three types of cardioplegia

Background. Sevoflurane protects the heart against reperfusioninjury even after cardioplegic arrest. This protection may dependon the cardioplegic solution. Therefore, we investigated theeffect of sevoflurane on myocardial reperfusion injury aftercardioplegic arrest with University of Wisconsin solution (UW),Bretschneider’s cardioplegia (HTK), and St Thomas’Hospital solution (STH). Methods. We used an isolated rat heart model where heart rate,ventricular volume, and perfusion pressure were constant. Thehearts underwent 30 min of normothermic ischaemia followed by60 min of reperfusion. Seven groups were studied (n=9 each).Three groups received 7°C cold cardioplegic solutions (UW,HTK, STH) during the first 2 min of ischaemia at a flow of 2ml min^–1. In three groups (UW+Sevo, HTK+Sevo, STH+Sevo),sevoflurane was additionally added to the perfusion medium (membraneoxygenator) at 3.8% (1.5 MAC) during the first 15 min of reperfusionafter cardioplegic arrest. Nine hearts served as untreated controlgroup (control). We measured left ventricular developed pressure(LVDP) and infarct size. Results. LVDP was similar in all groups during baseline (130(SEM 2) mm Hg). HTK and STH improved recovery of LVDP duringreperfusion from 5 (1) (control) to 67 (7) (HTK) and 52 (8)mm Hg (STH, both P<0.05), while UW had no effect on myocardialfunction (7 (2) mm Hg). In the sevoflurane-treated groups, LVDPat the end of the experiments was not significantly differentfrom the respective group without anaesthetic treatment (UW+Sevo11 (2); HTK+Sevo 83 (8); STH+Sevo 64 (8) mm Hg; P=ns). Infarctsize was reduced in the HTK and STH groups (HTK 20 (4); STH17 (3)%; P<0.05) compared with controls (39 (5)%; P<0.05),but not in the UW group (52 (4)%). Compared with cardioplegiaalone, sevoflurane treatment during reperfusion reduced infarctsize (UW+Sevo 31 (4); HTK+Sevo 8 (1); STH+Sevo 4 (1)%; P<0.05). Conclusion. We conclude, that the protection against reperfusioninjury offered by sevoflurane is independent of the three cardioplegicsolutions used. Br J Anaesth 2002; 88: 828–35