OBJECTIVETo define the ideal time window for intubation after rocuronium administration during target-controlled infusion (TCI) ofpropofol and sulfentanil.

METHODSOne hundred and twenty elective surgical patients (age range 18-55 years) were randomized into 4 groups (n=30) according to the intubation time after administration of the muscle relaxant. Patients with predicted difficult airway were excluded. General anesthesia was induced by TCI of propofol and sulfentanil. A senior anesthesiologist blinded for the randomization performed the intubations at 1, 2, 3, or 4 min after injection of rocuronium, and the vocal card visibility was evaluated upon full exposure of the vocal cord and the intubation conditions assessed according to Cooper's score.

RESULTSThe intubation conditions were excellent or good in all patients, but the vocal cord visibility at 2-4 min differed significantly from that at 1 min after rocuronium administration (P<0.01). Suppression of the neuromuscular function 1 min after rocuronium administration differed significantly from that at other time points (P<0.01).

CONCLUSIONThe condition of vocal cord can be more suitable for intubation at 2-4 min than at 1 min after rocuronium administration as the ideal time window for intubation during TCI of propofol and sulfentanil.