Clinical assessment of recovery from neuromuscular blockers, is it a safe practise - An observational study

Abstract

The incidence of residual neuromuscular paralysis (RNMB) with Train of four ratio<0.9 remains as high as 16% in PACU even after administration of reversal when neuromuscular monitoring is not done. Reversal with standard dose of neostigmine and extubation are done based on the clinical signs. We observed the clinical signs of neuromuscular recovery and correlated with neuromuscular monitoring to assess the degree of residual blockade in the post-operative period.100 Patients posted for surgery under general anaesthesia with endotracheal tube intubation and controlled ventilation were enrolled for the study after obtaining human ethical approval. Standard anaesthesia technique using morphine, propofol, vecuronium, isoflurane with low flow anaesthesia were administered for all patients. TOF was noted at the end of surgical procedure when patient resumed spontaneous respiration, during extubation, and at 15 minutes interval for one hour in the postoperative period. Hemodynamics were observed including respiratory rate. Overall 32 percent of patients had residual paralysis. 27% at 15 min, 26% at 30min, 6% at 45min and 3% at one hour in the postoperative period showed RNMB. Subgroup analysis showed that at the time administration of reversal 72 patients had (TOFR>0.4) and 28 had (TOFR<.0.4), showed significant difference in improvement in TOFR between 2 subgroups before reversal, immediate extubation and 15 min post extubation (p=0.00,0.001,0.003,) respectively. Clinical findings of neuromuscular reversal is not foolproof for complete recovery and standard dose neostigmine given during shallow block will accentuate the residual neuromuscular paralysis.