Avaliação da neuroleptoanalgesia com associação da acepromazina e meperidina em cães submetidos à anestesia geral inalatória com isoflorano em diferentes procedimentos cirúrgicas eletivos

Abstract

The aim of this work was to evaluate the neuroleptanalgesy effects over the cardiorespiratory system changes of dogs induced with ketamine and benzodiazepines, submitted to anesthesia by isoflurane. For that, thirty-six healthy adult dogs, males and females were used. A randomized complete block design was used to eliminate interferences related to age, weight, procedures, induction agents and sex, and the heterogeneity of the groups was reduced. The dogs were separate in two groups G1 and G2. G1 no received opioid in MPA, while G2 received meperidine (3mg/kg) associated with acepromazine (0,05mg/kg), applied intravenously. After 15 minutes the general anesthesia was induced with intravenously administration of combination of ketamine(2mg/kg) and benzodiazepines (0,05mg/kg). The dogs were submitted to inhalatory anesthesia with isoflurane. diluted in oxygen, through an anesthetic circuit with partial rebreathing of the gases with a diluent flow of 50ml/O₂/kg/min. During surgery, animals that had blood pressure 25% above baseline received 4mg/kg of intravenous Fentanyl and were withdrawn from the study. Physiological parameters such as: heart rate (HR) in beats per minute, respiratory rate in breaths per minute, arterial pressures: systolic (SBP), diastolic (DBP) and mean (MAP), oxygen saturation in red blood cells (SatO₂). To evaluate the electrocardiogram, a computerized electrocardiograph was used and the values for P wave amplitude (PmV ̶ in millivolts [mV]), P wave duration (Ps - milliseconds [ms]), PR , Duration of the QRS complex (ms), duration of the QT interval (ms), amplitude of the R wave (mV), were used velocity of 25mm/s in the DII lead with gain N). NLA in this study did not cause significant changes in the cardiorespiratory system variables evaluated, bringing more comfort to patients regarding the quality of induction, so the use of NLA techniques before general anesthesia should be used in routine of elective surgeries.