RESUMEN

Morphine is widely used as a preanesthetic agent in dogs, but it often produces signs of nausea and vomiting. Maropitant (MRP) and metoclopramide (MCP) prevent emesis attributable to the opioid agent apomorphine in dogs. We evaluated the antiemetic efficacy and the discomfort in response to SQ injection of MRP [1 mg/kg body weight (BW)], MCP (0.5 mg/kg BW), and normal saline (SAL; 0.1 mL/kg BW) administered to 63 dogs, 45 minutes prior to morphine (0.5 mg/kg BW) and acepromazine (0.05 mg/kg BW). Dogs were observed for signs of nausea (ptyalism, lip licking, and increased swallowing) and vomiting for 30 minutes after morphine/acepromazine. The incidence of emesis was 0% for MRP, 38% for MCP, and 71% for SAL (P < 0.001). The incidence of signs of nausea was not different between groups. Discomfort due to injection was higher after MRP (48%), than after MCP (9.8%) and SAL (4.8%) (P < 0.001).

Comparaison entre le maropitant et la métoclopramide pour la prévention de nausée et des vomissements induits par la morphine chez les chiens. La morphine est largement utilisée comme agent pré-anesthésique chez les chiens, mais elle produit souvent des symptômes de nausée et de vomissements. Le maropitant (MRP) et la métoclopramide (MCP) préviennent le vomissement causé par l'agent opioïde apomorphine chez les chiens. Nous avons évalué l'efficacité antiémétique et l'inconfort en réponse à une injection SC de MRP [1 mg/kg de poids corporel (PC)], de MCP (0,5 mg/kg PC) et d'une solution saline normale (SAL; 0,1 mL/kg PC) administrée à 63 chiens, 45 minutes avant la morphine (0,5 mg/kg PC) et l'acépromazine (0,05 mg/kg PC). Les chiens ont été observés pour détecter des signes de nausée (ptyalisme, lèchement des lèvres et déglutition accrue) et le vomissement pendant 30 minutes après l'administration de morphine/acépromazine. L'incidence du vomissement était de 0 % pour MRP, de 38 % pour MCP et de 71 % pour SAL (P < 0,001). L'incidence des signes de nausée n'était pas différente entre les groupes. L'inconfort attribuable à l'injection était supérieur après MRP (48 %) par rapport à celui après MCP (9,8 %) et SAL (4,8 %) (P < 0,001).(Traduit par Isabelle Vallières).

Asunto(s)

RESUMEN

OBJECTIVES: Neostigmine is routinely used to reverse non-depolarizing neuromuscular block. Given its indirect mechanism, a plateau may exist whereby increasing doses of neostigmine do not result in clinical benefit. This study was designed to measure the speed of reversal of vecuronium-induced neuromuscular block in isoflurane-anesthetized dogs after the administration of three doses of neostigmine as used in clinical practice. STUDY DESIGN: Prospective, crossover, randomized study. ANIMALS: Seven adult, mixed-breed dogs with a mean ± standard deviation (SD) age of 2.0 ± 0.8 years and weight of 19.1 ± 9.1 kg. METHODS: Dogs were anesthetized on three occasions with isoflurane and administered vecuronium (0.1 mg kg-1) intravenously (IV). The train-of-four (TOF) ratio was measured on the pelvic limb with acceleromyography. When the second twitch of the TOF had returned spontaneously, atropine (0.03 mg kg-1) and neostigmine (0.02, 0.04 or 0.07 mg kg-1) were administered IV. Time to reach a TOF ratio of ≥0.9 after neostigmine administration was recorded. RESULTS: Increasing the dose of neostigmine from 0.02 mg kg-1 to 0.04 mg kg-1 and 0.07 mg kg-1 resulted in significant reductions in mean ± SD reversal times (10.5 ± 2.3, 7.4 ± 1.1 and 5.4 ± 0.5 minutes, respectively) (p < 0.0001) and smaller coefficients of variation (22%, 15% and 10%, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Increasing the dose of neostigmine from 0.02 mg kg-1 to 0.04 mg kg-1 and 0.07 mg kg-1 produced faster and less variable reversal of vecuronium-induced neuromuscular block in isoflurane-anesthetized dogs. No ceiling effect was observed at this dose range.

Asunto(s)