Detecting Residual Weakness: an Update on Quantitative Neuromuscular Monitoring

Abstract

The purpose of this review is to summarize the newest generation of quantitative neuromuscular monitors and the different modalities that can be used to minimize the risk of postoperative residual weakness. New guidelines and consensus statements are emerging that emphasize the importance of using quantitative monitors whenever neuromuscular blocking agents (NMBAs) are administered. Additionally, there are new technologies emerging in this area. Residual neuromuscular blockade remains a common occurrence in the postoperative period. Even small degrees of residual muscle weakness can produce significant postoperative complications. Qualitative (subjective) assessment is an unacceptable technique to exclude residual neuromuscular blockade because fade is difficult to detect when train-of-four ratios are between 0.4 and 0.9. For that reason, using objective quantitative monitors is essential to confirm adequate recovery in all patients receiving NMBAs and ensure patient safety.