Effect of inhalation anaesthetics on total respiratory resistance in conscious ponies.
Total respiratory resistance was measured rapidly and non-invasively in 6 conscious ponies before and after they inhaled approximately 25% of the minimal anaesthetic concentration (0.25 MAC) of either enflurane, halothane, or isoflurane, over a 10 min period. The forced random noise (FRN) method was used to measure the impedance over the frequency range of 5 to 40 Hz and its real part, the resistance, was extracted from these impedance measurements. At the concentrations used, halothane appeared to have no effect on the total respiratory resistance; enflurane and isoflurane seemed to increase it but the changes were not statistically significant.
Hall
L W
LW
Department of Clinical Veterinary Medicine, University of Cambridge, UK.
Young
S S
SS
D000403:Airway Resistance / Q000187:drug effects*; D000769:Anesthesia, Inhalation / Q000662:veterinary*; D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D004737:Enflurane / Q000494:pharmacology; D006221:Halothane / Q000494:pharmacology; D006736:Horses / Q000502:physiology*; D007530:Isoflurane / Q000494:pharmacology; D011674:Pulse / Q000187:drug effects; D012119:Respiration / Q000187:drug effects
D000777:Anesthetics; D004737:Enflurane; D007530:Isoflurane; D006221:Halothane