Haemodynamic and organ blood flow responses to sevoflurane during spontaneous ventilation in the rat: a dose-response study.
To determine the systemic haemodynamic and organ blood flow responses to the administration of sevoflurane during spontaneous ventilation, heart rate, cardiac index, mean arterial pressure, arterial blood gases, and blood flows to the brain, spinal cord, heart, kidneys and splanchnic organs were measured awake (control values) and after 30 min of anaesthesia with 0.5, 1.0, 1.2 or 1.5 MAC sevoflurane in rats. Cardiac output and organ blood flows were measured using radiolabelled microspheres. The MAC (mean +/- SEM) of sevoflurane was found to be 2.30 +/- 0.05%. At each concentration, haemodynamic variables were similar to awake values with the exception of a 12% reduction in mean arterial pressure at 1.5 MAC (P less than 0.01). Arterial PCO2 increased in a dose-related fashion. Cerebral and spinal cord blood flows increased at 1.2 and 1.5 MAC whereas coronary and renal blood flows did not change significantly. Portal tributary blood flow and preportal vascular resistance were unaffected. Hepatic arterial flow increased by 63% at 1.5 MAC (P less than 0.05) but total liver blood flow remained unchanged compared with awake values. In conclusion, the administration of sevoflurane during spontaneous ventilation produces a high degree of cardiovascular stability and maintains blood flow to major organs in the rat.
Crawford
M W
MW
Department of Anaesthesia, Hospital for Sick Children, Toronto, Ontario, Canada.
Lerman
J
J
Pilato
M
M
Orrego
H
H
Saldivia
V
V
Carmichael
F J
FJ
D000769:Anesthesia, Inhalation; D000777:Anesthetics / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001775:Blood Circulation / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D002302:Cardiac Output / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004987:Ethers / Q000008:administration & dosage / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D008102:Liver Circulation / Q000187:drug effects; D008738:Methyl Ethers; D011650:Pulmonary Alveoli; D011652:Pulmonary Circulation / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012039:Regional Blood Flow / Q000187:drug effects; D012119:Respiration; D000077149:Sevoflurane; D013116:Spinal Cord / Q000098:blood supply; D013318:Stroke Volume / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D000777:Anesthetics; D004987:Ethers; D008738:Methyl Ethers; D002245:Carbon Dioxide; D000077149:Sevoflurane