Background:The subjective experience of residual neuromuscular blockade after emergence from anesthesia has not been examined systematically during postanesthesia care unit (PACU) stays. The authors hypothesized that acceleromyography monitoring would diminish unpleasant symptoms of residual paresis during recovery from anesthesia by reducing the percentage of patients with train-of-four ratios less than 0.9. Methods: One hundred fifty-five patients were randomized to receive intraoperative acceleromyography monitoring (acceleromyography group) or conventional qualitative trainof-four monitoring (control group). Neuromuscular management was standardized, and extubation was performed when defined criteria were achieved. Immediately upon a patient's arrival to the PACU, the patient's train-of-four ratios were measured using acceleromyography, and a standardized examination was used to assess 16 symptoms and 11 signs of residual paresis. This examination was repeated 20, 40, and 60 min after PACU admission. Results: The incidence of residual blockade (train-of-four ratios less than 0.9) was reduced in the acceleromyography group (14.5% vs. 50.0% control group, with the 99% confidence interval for this 35.5% difference being 16.4 -52.6%, P Ͻ 0.0001). Generalized linear models revealed the acceleromyography group had less overall weakness (graded on a 0 -10 scale) and fewer symptoms of muscle weakness

The incidence and severity of symptoms of muscle weakness were increased in the PACU in patients with a TOF <0.9.

Based on P300 data, 100% of the simple guilty (no countermeasure use) and 92% of the innocent subjects were correctly identified as having or not having concealed information. In the countermeasure groups, detection rates varied from 71% to 92% across the different groups. Notably, in the present study with eight irrelevant items, simultaneous countermeasure use was indicated by elevated RT in the 50% and 75% countermeasure proportion groups, which it was not, previously, with 50% (two) countermeasures and four irrelevants.

neuromuscular function. The quantitative TOF value is the criterion standard when it comes to preventing premature extubation in the face of residual block. Comment by Kathryn E. McGoldrick, MD Disclosure: The author declares no conflict of interest. REFERENCES 1. Brull SJ, Murphy GS. Residual neuromuscular block: lessons unlearned. Part II: methods to reduce the risk of residual weakness. Anesth Analg. 2010;111:129Y140. 2. Viby-Mogensen J, Jensen NH, Engbaek J, et al. Tactile and visual evaluation of the response to train-of-four nerve stimulation.W hen neuromuscular-blocking agents (NMBAs) are given to patients intraoperatively, they may later experience residual neuromuscular blockade in the postanesthesia care unit (PACU). Up to 64% of patients given intermediate-acting NMBAs have evidence of incomplete neuromuscular recovery, defined as a train-of-4 (TOF) ratio less than 0.9. Train-of-4 ratios less than 0.9 are associated with reduced upper airway volumes, airway obstruction, hypoxemia, and postoperative pulmonary complications along with notable delays in reaching PACU discharge criteria. Small degrees of residual blockade can be reliably detected only with the use of quantitative neuromuscular monitoring. This randomized study compared the use of acceleromyography monitoring with the conventional qualitative TOF monitoring in patients during their PACU stay.A total of 155 patients undergoing elective surgery requiring neuromuscular blockade with a duration of at least 60 minutes were randomly assigned to the acceleromyography or TOF control group. Anesthetic management was standardized in all patients and standard monitoring was applied in the operating room. Anesthesia was with propofol, lidocaine, fentanyl, and rocuronium, supplemented with boluses of fentanyl. Neuromuscular monitoring (TOF-Watch SX; Bluestar Enterprises, Chanhassen, Minn) was applied to patients in both groups on arrival in the operating room. In the acceleromyography group, the data panel of the TOF-Watch SX was uncovered, and the TOF ratio information displayed was then used to guide intraoperative management. In the control group, the cover over the display panel was not removed and the TOF-Watch SX was used as a standard qualitative peripheral nerve stimulator because clinicians did not have access to the TOF ratio data. Additional doses of rocuronium were given to maintain a TOF count of 2 to 3 during portions of the operation requiring neuromuscular blockade. At the end of the surgery, when a TOF count of at least 3 was present, neuromuscular blockade was reversed with neostigmine 50 Kg/kg and glycopyrrolate 10 Kg/kg. Immediately on arrival to the PACU, the patient's TOF ratios were measured using acceleromyography. A standardized examination was used to assess 16 symptoms and 11 signs of residual paresis and repeated 20, 40, and 60 minutes after PACU admission. Aldrete scores were assessed at arrival in the PACU and every 10 minutes for the next 60 minutes. Times required to meet discharge criteria and actual discharge were recor...