Determination of the ED50 of Isoflurane and Evaluation of the Isoflurane‐Sparing Effect of Butorphanol in Cockatoos (Cacatua spp.)

Abstract

The use of butorphanol as an analgesic in a psittacine species was evaluated by determining its isoflurane-sparing effects. The Effective Dose 50 (ED50) of isoflurane was determined using a bracketing technique based on the purposeful movement elicited by pressure applied to a digit with a hemostat. The ED50 of isoflurane for 11 cockatoos (four greater sulfur crested, three lesser sulfur crested, and four citron crested) was determined to be 1.44 +/- 0.07%. After the administration of 1 mg/kg of butorphanol tartrate intramuscularly (IM), the ED50 was significantly (P < .05) decreased to 1.08 +/- 0.05%. Physiological variables that changed significantly included decreases in heart rate, tidal volume (Vt), inspiratory (Ti) and expiratory times (Te), and an increase in respiratory rate. No complications resulted because of these changes. Based on the results, butorphanol produces an isoflurane-sparing effect in cockatoos and has the potential to be a useful analgesic in psittacines.

Dose-related Cardiovascular Effects of Isoflurane in Chickens during Controlled Ventilation.

“…In the present study, we determined the minimal anesthetic concentration as an index of anesthetic potency in birds with a method previously reported by Ludders et al [9]. The minimal anesthetic concentration in our chickens was similar to that previously reported in chickens during controlled ventilation (1.05 to 1.24%) [2] and that in other avian species studied during spontaneous ventilation, such as ducks (1.30%) [7], cranes (1.34%) [9], and cockatoos (1.44%) [3]. This also was within the range of minimum alveolar concentration reported for mammals (1.15-2.05%) [15].…”

“…Although birds do not have an alveolar lung, anesthetic potency has been studied using a method similar to that for mammals [3,[7][8][9]. In the present study, we determined the minimal anesthetic concentration as an index of anesthetic potency in birds with a method previously reported by Ludders et al [9].…”

Tramadol ou butorfanol: modelo analgésico pós osteossíntese experimental de úmero em galos ( Gallus gallus domesticus )

“…Em relação à PAS é possível observar uma diminuição dos valores no momento M3 em relação ao momento basal no GT, não sendo observado nos demais tempos correspondentes ao estímulo cirúrgico. Curro, Brunson & Paul-Murphy (1994) explicam que a diminuição da PAS deve-se ao fato que os opioides totais aumentam o tônus vagal em aves de forma semelhante ao que acontece em mamíferos, levando as aves desenvolver bradicardia com diminuição indireta da PAS, além do efeito sinérgico com o isoflurano que também é responsável por esta diminuição através da sua atuação diretamente sobre a vasculatura periférica, diminuindo a resistência vascular sistêmica, através da vasodilatação (Naganobu & Hagio 2000). Valores semelhantes de PAS foram observados por Guimarães et al (2007), em pombos anestesiados com morfina e isoflurano.…”

Efeitos sedativos da administração intranasal ou intramuscular de midazolam associado ou não ao butorfanol em periquito autraliano (Melopsitacus undulatus)

“…Além de causar pouca depressão respiratória, o butorfanol (1 mg.kg -1 ) quando administrado pela via intramuscular, resulta em menor requerimento de anestésicos inalatórios para manutenção anestésica em cacatuas (Curro et al 1994) e galinhas-de-angola (Escobar et al 2012). …”