Recovery of train-of-four ratio to 0.70 and 0.90 is delayed in type 2 diabetes with vecuronium-induced neuromuscular block.

CONTEXT: The recovery profile of train-of-four ratio to more than 0.70 in patients with diabetes mellitus has not been well investigated. OBJECTIVE: Our primary objective was to evaluate the spontaneous recovery profile of neuromuscular block by vecuronium until train-of-four ratio more than 0.90 in patients with type 2 diabetes mellitus compared with controls, using first dorsal interosseous electromyography. DESIGN: Single-centre prospective case-control study. SETTING: The operating theatres of Fukuoka University Hospital. PATIENTS: Fourteen adults with type 2 diabetes mellitus (diabetes mellitus group) and 14 control patients (control group) were included in this study. INTERVENTION: Evoked responses to train-of-four stimuli were measured by electromyography at the first dorsal interosseous muscle. General anaesthesia was induced with propofol, fentanyl and remifentanil. Vecuronium (0.1  mg kg) was administered to all patients. Anaesthesia was maintained with propofol, fentanyl and remifentanil. The neuromuscular block was assessed until spontaneous recovery to train-of-four ratio more than 0.90. MAIN OUTCOME MEASURES: Recovery times to train-of-four ratio 0.70 and 0.90. RESULTS: Recovery times to train-of-four ratio 0.70 and 0.90 were significantly longer in the diabetes mellitus group than the control group (P = 0.041 and P = 0.027, respectively). The time from train-of-four ratio 0.25 to 0.90 was also significantly longer in the diabetes mellitus group than the control group (P = 0.029). In five of 14 patients in the diabetes mellitus group, the time from train-of-four ratio 0.25 to 0.90 was longer than 60  min, which is longer than the duration of action of neostigmine. The time from train-of-four ratio 0.25 to 0.90 was longer than 60  min in only one of 14 in the control group. CONCLUSION: Recovery times to train-of-four ratio 0.70 and 0.90 were delayed in patients with type 2 diabetes mellitus. Neuromuscular block by vecuronium should be carefully monitored in patients with type 2 diabetes mellitus until recovery of train-of-four ratio to a safe level is confirmed.