Effects of Cisatracurium in Sevoflurane and Propofol Requirements in Dog-Undergoing-Mastectomy Surgery

Simple Summary Gas anesthesia is widely used in clinical practice; it results in better management of the surgical patient by reducing the risks attached to anesthesia. Neuromuscular blockers, such as cisatracurium besylate, result in muscle relaxation of varying dose-dependent duration; however, they do not have analgesic and hypnotic efficacy, which is the reason of the combination with analgesic and anesthetic substances. The present study aimed to evaluate the possible reduction of anesthetic drugs used in bitches undergoing mastectomy surgery. The results obtained showed that the cisatracurium resulted in a good degree of myorelaxation without the manifestation of side effects and, more importantly, allowed the reduction of anesthetics used for induction (propofol) and maintenance (sevoflurane) of anesthesia. The possibility of reducing the doses of the drugs used maintaining also a good anesthesia enriches the scenario of different protocols that can be used in the canine patient. The purpose of the present study was to test whether the addition of cisatracurium in combination with propofol and sevoflurane would result in a change in doses of used anesthetic drugs. Ten dogs (Group A) undergoing elective unilateral mastectomy surgery were included in the study. To induce and maintain anesthesia, subjects received propofol and sevoflurane at varying doses; analgesia was performed with remifentanil. After three months, the same subjects (Group B) underwent contralateral mastectomy and received the same anesthetic protocol with the addition of cisatracurium at a dosage of 0.2 mg/kg(-1). The following parameters were monitored during anesthesia: heart rate, systolic blood pressure, end-tidal CO2, oxygen saturation, halogenate requirement, and rectal temperature at baseline (T-0), induction (T-1), 5 (T-5), 10 (T-10), 15 (T-15), 20 (T-20), 25 (T-25), 30 (T-30), and 35 (T-35) time points. In Group A, halogenate requirement was reduced at all the time points other than T1 (p < 0.001); in Group B, the percentage of halogenate requirement was already reduced at T-1 and remained constant during the experimental period, showing no significant intragroup differences. The dose requirements of sevoflurane and propofol varied significantly between the two groups, with significantly lower dosages in the Group B (the cisatracurium-treated group). Moreover, patients treated with cisatracurium showed a stable anesthetic plan. The nondepolarizing-muscle-relaxant cisatracurium besylate could be considered a useful adjunct to anesthetic protocols.