Grip strength can be used to evaluate postoperative residual neuromuscular block recovery in patients undergoing general anesthesia

Background: Residual postoperative neuromuscular blockade is an important clinical issue. Neuromuscular monitoring is usually used to evaluate neuromuscular recovery in patients undergoing general anesthesia. However, this procedure is inconvenient and not widely adopted. We aimed to examine the correlation between grip strength and train-of-four ratio (TOFr) to examine whether assessing grip strength can be used clinically to monitor residual neuromuscular blockade. Methods: One hundred twenty patients with ASA I or II scheduled for laparoscopic cholecystectomy under general anesthesia were enrolled in this study. All patients were randomly selected to receive standard anesthesia induction with either 0.6 mg.kg(-1) rocuronium or 0.2 mg.kg(-1) cisatracurium. Grip strength was tested in all patients using an electronic device before anesthesia and when TOFr values of 0.7, 0.8, and 0.9, and an hour later of TOFr value of 0.25. The time required for a change in TOFr values from 0.25 to 0.75 and 0.9 was evaluated. Spearman rank correlation analysis was performed to determine correlations between grip strength and TOFr. Results: Spearman rank correlation analysis indicated that there was a significant correlation between grip strength and TOFr during patient recovery from general anesthesia (correlation coefficient for grip strength recovery [r(s)] = 0.886). Subgroup analysis revealed that there were no differences in mean maximum grip value recovery between patients treated with rocuronium and those treated with cisatracurium when TOFr was 0.7, 0.8, and 0.9 or when the TOFr was 0.25 after 60 minutes (all P>.05). Recovery of TOFr from 0.25 to 0.75 and from 0.25 to 0.9 was longer in patients treated with rocuronium than in those treated with cisatracurium (both P<.001). Conclusion: There was a strong correlation between grip strength and TOFr during recovery from general anesthesia. Evaluation of grip strength can be used as an additional strategy to evaluate postoperative residual neuromuscular blockade.