Evaluation of the effects of a single bolus of cisatracurium as part of an anesthetic protocol in cats undergoing orthopedic surgery.

Non-depolarizing neuromuscular blocking agents (NMBAs) are commonly used in human anesthesia but remain uncommon in veterinary medicine. This study evaluated the effects of 0.5 mg/kg cisatracurium IV on muscle relaxation, cardiovascular variables and postoperative pain in cats undergoing orthopedic surgery. Twenty-four cats were randomly assigned to a control group (Group C) or a treatment group receiving cisatracurium (Group M) immediately after induction. Neuromuscular function was monitored using a calibrated train-of-four (TOF) device. Postoperative pain was assessed with the short form of the Glasgow Feline Composite Measure Pain Scale (CMPS-Feline). The mean time to suppression of muscle contraction was 2.6 ± 0.8 min, with peak suppression (90%) at 3.0 ± 0.7 min, a mean duration of 23.3 ± 4.4 min, and complete recovery at 27.3 ± 8.6 min. Group M required lower sevoflurane concentrations to maintain anesthesia compared to Group C (p < 0.001) and had a shorter mean surgical time (25.3 ± 3 min vs. 31.5 ± 4 min; p < 0.001). Pain scores were also lower in Group M (p = 0.01). These findings demonstrate that cisatracurium effectively induces neuromuscular block (NMB) and improves surgical conditions, resulting in lower postoperative pain scores in cats undergoing femoral fracture repair.