POTENCY OF ISOFLURANE AND NITROUS-OXIDE IN CONVENTIONAL SWINE

  • 1 January 1985
    • journal article
    • research article
    • Vol. 35  (1) , 76-78
Abstract
The minimum alveolar concentration (MAC) of isoflurane in O2 was determined to be 1.55 .+-. 0.08 (SEM) [standard error of mean] volumes % in 12 pigs (Sus scrofa). Values for isoflurane MAC in the presence of 50% (I-50% N2O) and 66% (I-66% N2O) N2O were determined in 9 and 6 of these same animals, respectively, and equalled 1.03 .+-. 0.05 vol % for I-50% N2O and 0.95 .+-. 0.07 vol % for I-66% N2O. Animals respired spontaneously and arterial blood pressure (AP), heart rate (HR), rectal body temperature, and arterial blood gases (PO2, [partial pressure O2] PCO2 and pH) were recorded throughout the study period. These parameters were within normal limits near MAC for all 3 gas combinations. The MAC for isoflurane in swine was similar to that for other animals and man and the use of this agent was associated with rapid and uneventful anesthetic induction and recovery. The addition of 50% and 66% N2O reduced the isoflurane MAC by 30% and 42%, respectively.