title: Retrospective analysis of spontaneous recovery from neuromuscular blockade produced by empirical use of rocuronium.
abstract: OBJECTIVE
  A train-of-four ratio (TOF ratio) of >0.9 should be the clinical cut-off to avoid residual paralysis. However, it is not rare to extubate patients without measurement of the TOF ratio, although the safe interval from the last administration of rocuronium assuring a TOF ratio of >0.9 has not been established in the daily clinical setting. In this study, to estimate the safe interval to avoid residual paralysis, we retrospectively selected patients in whom the TOF ratio was measured during remifentanil administration before extubation, and we studied the characteristics of recovery from the neuromuscular blockade produced by the empirical use of rocuronium.
  
  
  METHODS
  Patients undergoing surgery under general anesthesia with sevoflurane and remifentanil were studied (n = 134). Rocuronium was administered at 0.7-1.0 mg/kg for tracheal intubation, and repeated bolus administration (10 mg) or continuous infusion (15-25 mg/h) was performed by the anesthesiologists in charge of the patient to maintain intraoperative paralysis. At the end of the surgery, the TOF ratio was measured, during remifentanil infusion and the contribution of clinical parameters to spontaneous recovery from the rocuronium-induced paralysis was studied by multivariate logistic regression analyses.
  
  
  RESULTS
  Spontaneous recovery from rocuronium-induced paralysis within 2 h after the last administration of rocuronium varied among the patients. Multivariate logistic regression analyses showed that age (P = 0.002) and time elapsed from the last administration of rocuronium (P < 0.0001) significantly contributed to TOF recovery, and elderly patients demonstrated significantly slower recovery.
  
  
  CONCLUSIONS
  Because of the large variation in the recovery from rocuronium-induced paralysis, TOF-based evaluation of residual paralysis is essential to determine the appropriate indication for reversal, especially for elderly patients.
authors.affiliation: Department of Anesthesiology, Tokyo Medical and Dental University, Graduate School of Medicine, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Tokujiro
authors.initials: T
authors.lastname: Uchida
authors.forename: Yudai
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ito
authors.forename: Koshi
authors.initials: K
authors.lastname: Makita
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000732:Androstanols / Q000008:administration & dosage*; D000762:Anesthesia Recovery Period; D000768:Anesthesia, General / Q000379:methods; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods; D016015:Logistic Models; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage; D008875:Middle Aged; D015999:Multivariate Analysis; D019148:Neuromuscular Blockade / Q000379:methods*; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage*; D010880:Piperidines / Q000008:administration & dosage; D000077208:Remifentanil; D012189:Retrospective Studies; D000077123:Rocuronium; D000077149:Sevoflurane; D055815:Young Adult
chemical_list: D000732:Androstanols; D008738:Methyl Ethers; D003473:Neuromuscular Nondepolarizing Agents; D010880:Piperidines; D000077149:Sevoflurane; D000077208:Remifentanil; D000077123:Rocuronium