Methylene blue in preventing hemodynamic and metabolic derangement following superior mesenteric artery clamping/unclamping: an intratracheal vs. intraperitoneal dose-response study.
Intestinal ischemia-reperfusion affects hemodynamics. We studied intratracheal vs. intraperitoneal methylene blue (MB) attenuation of hemodynamic and metabolic deterioration following superior mesenteric artery (SMA) clamping/unclamping. Murine SMAs (5/group) were clamped for 1 h. MB (2, 6, 20, or 60 mg/kg [MB-2, MB-6, MB-20, and MB-60]) was administered intraperitoneally or intratracheally 10 min before unclamping. Observation continued for another 3 h. Circulating xanthine oxidase and base deficit levels doubled among ischemia non-treated and ischemia MB-2- and MB-60-treated groups, blood pressure decreased by 50%, and heart rate increased by 35%, compared to controls (non-clamped/unclamped and non-MB-treated rats, P < 0.01). These three ischemia groups needed 3-fold the amount of fluid to maintain systolic pressure > or =60 mmHg than controls (P < 0.01). Only the MB-6 and MB-20 intraperitoneal and intratracheal regimens similarly afforded hemodynamic stability in ischemic animals; base deficit and resuscitation volumes normalized as well. No drug regimen affected heart rate. We concluded that intraperitoneal and intratracheal MB at specific doses prevented systemic derangement following SMA clamping/unclamping.
Weinbroum
Avi A
AA
Post-Anesthesia Care Unit, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Israel.
Goldin
Ilya
I
Kluger
Yoram
Y
Szold
Amir
A
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D007274:Injections, Intraperitoneal; D008297:Male; D017538:Mesenteric Artery, Superior / Q000503:physiopathology* / Q000601:surgery; D008751:Methylene Blue / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000503:physiopathology; D012119:Respiration / Q000187:drug effects*; D014969:Xanthine Oxidase / Q000097:blood
D014969:Xanthine Oxidase; D008751:Methylene Blue