Assessing Residual Neuromuscular Blockade Using Acceleromyography Can Be Deceptive in Postoperative Awake Patients

Postoperative awake patients may have significant residual neuromuscular block. In awake patients, the results of accelerometry are affected by extra movements to which the thumb may be subject. In this study, we evaluated the repeatability of train-of-four (TOF) ratio using acceleromyography in 253 patients recovering from anesthesia. Immediately after arrival in the postanesthesia care unit, the ulnar nerve was stimulated with TOF stimulation. The evoked response at the thumb was measured by the TOF-Watch apparatus. The current intensity was 30 mA. Two TOF stimulations were applied and recorded at 30-s intervals. A Bland-Altman test was used. The Kappa (κ) test for clinical agreement between the two measurements was also calculated according to the presence or absence of a residual neuromuscular blockade, defined as a TOF ratio