Ciência Rural (Dec 2012)
Infusão contínua intravenosa de midazolam isolado ou associado ao fentanil para realização de endoscopia em suínos Continuous infusion rate of midazolam alone or in combination with fentanyl for endoscopy in swine
Abstract
Com este estudo objetivou-se avaliar o efeito cardiorrespiratório e a qualidade da anestesia e da recuperação pós-anestésica decorrentes da associação cetamina e xilazina seguida da infusão contínua intravenosa (IV) de midazolam isolado ou associado ao fentanil, em suínos. Foram avaliadas 10 porcas adultas, da raça Landrace, com peso médio de 170±4kg, submetidas à endoscopia. Todos os animais foram medicados pela via intramuscular com cetamina (4mg kg-1) associada à xilazina (2mg kg-1). Vinte minutos após, foi realizado um bolus IV de cetamina (2mg kg-1), seguida da infusão contínua IV de midazolam (0,5mg kg-1h-1 GM, n=5), ou midazolam (0,25mg kg-1h-1) associado ao fentanil (4µg kg-1 h-1 GMF, n=5). Foram avaliados: frequência cardíaca (FC) e ritmo cardíaco, pressão arterial sistólica (PAS), temperatura retal (T), frequência respiratória (f), variáveis hemogasométricas (PaO2, PaCO2, pH, HCO3-, SaO2), qualidade da anestesia e qualidade e tempo da recuperação anestésica (RA). A análise estatística foi realizada por meio de análise de variância, teste de Tukey e o teste não paramétrico de Mann-Whitney (PThe aim of this study was to evaluate the cardiopulmonary effects, the quality of anesthesia and the post-anesthetic recovery of ketamine and xylazine premedication following intravenous (IV) continuous rate infusion of midazolam alone or in combination with fentanyl, in swine. Ten Landrace adult pigs that underwent endoscopy were evaluated. All pigs were premedicated with ketamine (4mg kg-1) and xylazine (2mg kg-1) by intramuscular administration. After twenty minutes, intravenous ketamine (2mg kg-1) was injected, following IV continuous rate infusion of midazolam (0.5mg kg-1 h-1 GM, n=5) or midazolam (0.25mg kg-1 h-1) plus fentanyl (4µg kg-1 h¹ GMF, n=5). Heart and respiratory rates, systolic arterial blood pressure, rectal temperature, arterial blood gases, quality of anesthesia and recovery, and time for recovery were investigated. Statistical analysis was performed with One-Way ANOVA, Tukey test and Mann-Whitney test (P<0.05). The quality of anesthesia was similar between treatments, and endoscopy was able to be performed in both groups. Cardiopulmonary variables and blood gases did not differ between groups. The recovery time was 98±15 and 79±17 minutes in GM and GMF, respectively, without significant difference between treatments. The quality of recovery did not differ between groups. The results allowed us to conclude that both treatments provide cardiopulmonary stability and were satisfactory to swine endoscopy. However, despite of absence of significant difference, shorter time of recovery was observed with midazolam/fentanyl infusion.
