Timing of removal of the laryngeal mask airway

Abstract

SummaryPrevious studies reported that complications associated with removal of the laryngeal mask were more frequent in awake patients than in anaesthetised patients; however, these studies did not comply with the method described in the manufacturer's instruction manual. The reported incidences of regurgitation during the use of the laryngeal mask also differ considerably between studies. We studied these factors in 66 patients in whom the method described in the manual was used. After induction of anaesthesia, the laryngeal mask and a pH probe were inserted and the cuff of the mask was inflated with a minimum volume of air. Anaesthesia was maintained with nitrous oxide and isoflurane in oxygen. At the end of the operation, we randomly allocated patients to one of two groups and the laryngeal mask was removed either while they were still deeply anaesthetised or after they had regained consciousness. No apparent regurgitation occurred in any patient during operation, but one patient in the anaesthetised group regurgitated immediately after removal of the mask. The incidence of complications during or after removal of the laryngeal mask was significantly greater in the anaesthetised group than that in the awake group (p << 0.001; difference [95% CI]: 48.5 [30.5-66.5]%). Therefore, the laryngeal mask can be safely left in place until the patient has regained consciousness after emergence from anaesthesia.

Respiratory complications associated with tracheal extubationTiming of tracheal extubation and use of the laryngeal mask during emergence from anaesthesia

“…The laryngeal mask is less likely to produce stimulatory effects compared with a tracheal tube during emergence from anaesthesia [11,16]. For example, the incidence of coughing at removal of the laryngeal mask is reported to be up to 10% [13,16,17]. In the current study, straining almost always occurred when a tracheal tube was left in place until the patient had regained consciousness, whereas mild coughing occurred in only three of 20 patients (15%) immediately before removal of the laryngeal mask.…”

A randomized controlled trial comparing Laryngeal Mask Airway removal during adequate anesthesia and after awakening in children aged 2 to 6 years

“…In adults, it is generally recommended that the LMA be removed when patients become fully awake [1]. However, in pediatric patients, diverse recommendations have been suggested [2][3][4][5][6][7].…”

Target controlled remifentanil infusion for smooth laryngeal mask airway removal during emergence from desflurane–remifentanil anesthesia

“…In the state of deep anesthesia, however, elimination of airway protection may lead to airway obstruction and aspiration [2,3].…”