[Effects of sevoflurane, isoflurane, and halothane on regional myocardial blood flow in the ischemic canine heart].

The effects of sevoflurane (Sev), isoflurane (Iso), and halothane (Hal) on coronary circulation were studied in 30 dogs with acute coronary arterial stenosis. Regional myocardial blood flow (rMBF) was measured by hydrogen clearance method. There was no significant difference between each anesthetic agent in heart rate, mean arterial pressure, and cardiac output under any anesthesia level. As the inspired concentration of each anesthetic is increased, rMBF decreased significantly and rMBF/rate-pressure-product (RPP) ratio increased in normal area. In Sev and Iso groups, rMBF/RPP ratios were higher than that in Hal group, suggesting luxury perfusion caused by Sev and Iso. In the ischemic area, rMBF was reduced depending on the inspired concentration of each anesthetic agent and transmural maldistribution of blood flow was not observed with any anesthetic agent. Nevertheless the ratio of rMBF in ischemic area to that of normal area was decreased in Sev and Iso groups, but not in Hal group. In this study, neither Sev nor Iso worsened regional myocardial ischemia. However, Sev-induced coronary vasodilation may cause regional myocardial ischemia by redistribution of flow under steal prone condition.