Isoflurane, and not halothane, increases mesenteric blood flow supplying esophageal ileocoloplasty

Regional ischemia may induce anastomotic leakage or stenosis after esophageal reconstruction using retrosternal interposition of an ileocolic graft. These complications may be related to systemic or local hemodynamic alterations. This study was designed to evaluate the influence of inhalational anesthetic agents on the intestinal circulation supplying these ileocolic grafts. Seven patients (age 30 +/- 5 yr, mean +/- standard deviation [SD]) were studied in the immediate postlaparotomy period. Miniaturized Doppler implantable microprobes were sutured to the single artery supplying the graft and connected to an 8-MHz pulsed Doppler flowmeter. Continuous fentanyl infusion (300 micrograms.h-1) was maintained throughout the study. Measurements were performed at the end of four 30-min periods, which were, successively: first control; isoflurane or halothane anesthesia; second control; and isoflurane or halothane anesthesia. Isoflurane and halothane were administered in cross sequence with end-tidal concentration of 0.8% and 0.5%, respectively, to induce equipotent anesthesia. Both anesthetics induced similar decreases in mean systemic arterial pressure (MAP), cardiac output (CO), and systemic vascular resistance. During isoflurane, mean mesenteric blood flow (MBFm) supplying the graft was increased (+38%; P less than 0.05), and the mesenteric vascular resistance index (MVRI; -44%; P less than 0.05) was decreased, leading to an increase in the MBFm/CO ratio (P less than 0.05). Halothane changed neither the MBFm nor the MBFm/CO ratio, despite a mild decrease in MVRI (-14%; P less than 0.05). Diastolic blood flow velocity increased significantly (2.3 +/- 0.9 vs. 0.8 +/- 0.3 cm.s-1, P less than 0.05) only with isoflurane, suggesting a local vasodilation not observed with halothane.(ABSTRACT TRUNCATED AT 250 WORDS)