Trazodona oral como adjuvante na anestesia intravenosa total em cães

Abstract

Total intravenous anesthesia (TIVA) is widely used in veterinary medicine due to its ability to promote smoother recoveries and exert less impact on physiological parameters compared to inhalational anesthesia. Propofol is the primary agent used in this technique, although its dose-dependent adverse effects are a concern. To mitigate these effects, it is common to combine propofol with adjuvant drugs. Trazodone, an atypical antidepressant with anxiolytic properties, has gained attention in the management of canine stress-related conditions; however, its application as an anesthetic adjuvant remains underexplored. Few studies have investigated its interaction with anesthetic agents, particularly in the context of TIVA. This study evaluated the effects of trazodone as an adjuvant to propofol-based TIVA in dogs undergoing elective orchiectomy. Eighteen dogs were randomly assigned to two groups: placebo (GP) or trazodone (GT), receiving 12 mg/kg orally. Physiological parameters, sedation scores, laboratory tests, electrocardiography, recovery times, and adverse effects were assessed at various time points throughout the study. Following premedication with methadone (0.3 mg/kg), dogs underwent elective orchiectomy under TIVA with propofol. The induction dose of propofol was lower in the trazodone group (4.0 mg/kg) compared to the placebo group (5.5 mg/kg), while the infusion rate and recovery times were similar between groups. Trazodone was well tolerated, with minimal clinical adverse effects. Sedation scores increased in both groups, with slightly higher scores in the GT during the pre-anesthetic period, suggesting a possible progressive tranquilizing effect. Cardiovascular, respiratory, electrocardiographic, and laboratory parameters remained stable in both groups, with isolated changes showing no clinical relevance. In the GT, urinary findings were consistent with improved hemodynamics, without evidence of hepatic or renal toxicity. It is concluded that oral trazodone at 12 mg/kg is safe as an adjuvant in propofol-based TIVA, reducing the required induction dose and promoting greater clinical stability during the perioperative period, making it a promising option in anesthetic protocols for dogs.