Validity and reliability of head lift and tongue depressor test for diagnosis of the residual block

BACKGROUND: Head lift (HL) for 5 seconds and tongue depressor (TD) test have been used for diagnosis of the residual block after using the nondepolarizing muscle relaxants. We investigated validity and reliability of HL, TD, and both of them (HLTD). METHODS: Four-hundred-thirteen patients were enrolled in this study. Neuromuscular blockade was maintained with rocuronium and reversed with pyridostigmine and glycopyrrolate. TOF ratio was quantified by acceleromyograph in the recovery room. HL and TD test were performed in the patients who could respond to verbal command of the investigator. We analyzed the sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio, area under the cure (AUC) from ROC analysis and kappa statistics. RESULTS: Prevalences of residual block were 13%, 32% and 78% at 0.7, 0.9 and 1.0 of TOF ratio cutoff value, respectively. Specificity was good for HL (79.7-86.8%), TD (94.2-97.8%) and HLTD (77.8-85.7%), but sensitivity was not. Positive predictive value was higher in TD than HL and HLTD, and negative predictive value was similar among them. Positive and negative likelihood ratio was higher in TD than HL and HLTD. AUC had no difference among HL, TD and LTD. Kappa statistics were showed minimal or moderate relationship between clinical test and train of four responses. CONCLUSIONS: We concluded that HL, TD and HLTD were not good tools for diagnosis of the residual block in a view of validity and reliability.

The Influence of Patient Controlled Analgesia on the Recovery of Muscle Power and Respiratory Function following Intraoperative Muscle Relaxants / 대한마취과학회지

BACKGROUND: Residual muscle paralysis after anesthesia is reduced with the advent of intermediate-acting neuromuscular blocking drugs, yet the incidence is as high as about 10 percent. Opioids in patient-controlled analgesia (PCA) may cause respiratory depression and other problems after anesthesia. The purpose of this study is to evaluate the influence of PCA on the SPO2, TOF ratio, head-lift and tongue protrusion during recovery room stay following intraoperative muscle relaxants. METHODS: 120 patients aged from 20 to 65 in ASA class I and II were divided into control or PCA groups. All patients received rocuronium (0.9 mg/kg) or atracurium (0.5 mg/kg) for tracheal intubation, and maintenance of relaxation was done with atracurium 0.2 mg/kg/hr during inhalation anesthesia. Reversal of block was done with pyridostigmine 0.15 mg/kg and glycopyrrolate 0.2 mg. SpO2, TOF ratio, 5 sec-head lift, tongue protrusion tests were evaluated in the recovery room. RESULTS: IV-PCA did not influence the incidence of residual block, SPO2, TOF ratio during recovery room stay for 20 minutes, but influenced negatively 5 sec-head lift test, tongue protrusion test only immediately after arrival at the recovery room. CONCLUSIONS: Since IV-PCA decreased the ability to perform head-lift and tongue protrusion early postoperatively, it is recommended that patients with IV-PCA should be carefully managed against the risk of aspiration or upper respiratory obstruction during their early recovery room stay.