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 (T⁰), induction (T¹), 5 (T⁵), 10 (T¹⁰), 15 (T¹⁵), 20 (T²⁰), 25 (T²⁵), 30 (T³⁰), and 35 (T³⁵) 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 T¹ 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.

The aims of the study included evaluating the effects of levobupivacaine combined with cisatracurium on akinesia and mydriasis when administered by peribulbar injection, and evaluating if the chosen dose of cisatracurium is enough to avoid the use of systemic neuromuscular blockade in cats. The animals were divided into four groups as follows: group L received 1.25 mg kg⁻¹ levobupivacaine administered by peribulbar injection; group LC received the same dose of levobupivacaine combined with 0.01 mg kg⁻¹ of cisatracurium administered by peribulbar injection; group C received 0.01 mg kg⁻¹ of cisatracurium administered by peribulbar injection; group GC received 0.01 mg kg⁻¹ of cisatracurium intravenously. Physiological variables, intraocular pressure, akinesia, and mydriasis were measured before and up to 30 min after peribulbar injection. The onset of akinesia, duration of akinesia, and train of four (TOF) were evaluated. Physiological variables remained in the physiological range in all groups. Effective akinesia and mydriasis were observed in all groups. The (TOF) was 0.9 in all groups. Throughout the study was observed in group LC a shortened onset of akinesia and a prolonging its duration. The peribulbar injection of cisatracurium and levobupivacaine provided effective akinesia and mydriasis, and shortened the onset of akinesia while prolonging its duration.