Context-sensitive recovery of neuromuscular function from vecuronium in dogs: Effects of dose and dosing protocol

• Published in: The veterinary journal (1997) 2019-06, Vol.248, p.14-17
• Main Authors: Lorenzutti, A.M., Zarazaga, M.P., Sakai, D.M., Nejamkin, P., Rosetti, V., Duran, V., Martin-Flores, M.
• Format: Article
• Language: English
• Subjects: Acceleromyography; Anesthesia; Anesthesia Recovery Period; Anesthesia, General - veterinary; Animals; Dogs - physiology; Dose-Response Relationship, Drug; Electric Stimulation; Female; Injections, Epidural - veterinary; Male; Muscle, Skeletal - drug effects; Neostigmine; Neuromuscular; Neuromuscular Blocking Agents - administration & dosage; Neuromuscular Blocking Agents - pharmacology; Neuromuscular Junction - drug effects; Random Allocation; Thoracic Vertebrae; Vecuronium Bromide - administration & dosage; Vecuronium Bromide - pharmacology
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2019.04.004

•Increasing the dose of vecuronium prolonged the duration of relaxation but also slowed down the speed of spontaneous recovery.•Dividing the dose into smaller aliquots increased the duration of relaxation and shortened the recovery period.•The speed of recovery from neuromuscular block depended on the dose of the blocker and how that dose was administered. Recovery of neuromuscular function is a gradual phenomenon whereby function progresses from absent to normal. The speed of spontaneous recovery can be used to predict the time when neuromuscular function is expected to be restored. However, the speed of recovery might be affected by the dose of the neuromuscular blocker administered, and by the dosing regimen of that dose. The effects of both factors on the speed of spontaneous recovery from vecuronium were evaluated. Seven dogs were anesthetized three times and the train-of-four (TOF) ratio was measured with acceleromyography. Vecuronium was administered at 0.1 mg/kg, 0.2 mg/kg, or 0.1 mg/kg followed by two doses of 0.05 mg/kg was administered each time. In the divided-dose treatment group, aliquots were administered on return of the first twitch (T1) of the TOF from the previous dose. The duration of surgical block, from injection to return of T1, was longest for the divided-dose protocol, intermediate for 0.2 mg/kg single bolus, and shortest for 0.1 mg/kg (P