Anaesthesia, 2009, 64, pages 1289–1294 doi:10.1111/j.1365-2044.2009.06140.x ......
Risk of pulmonary aspiration with laryngeal mask airway and tracheal tube: analysis on 65 712 procedures with positive pressure ventilation
A. Bernardini1 and G. Natalini2
1 Chairman, 2 Consultant, Department of Anaesthesia, Intensive Care and Emergency Fondazione Poliambulanza Hospital, Brescia, Italy
Summary We compared the risk of pulmonary aspiration in patients whose lungs were mechanically ventilated through a laryngeal mask airway (35 630 procedures) or tracheal tube (30 082 proce- dures). Three cases of pulmonary aspiration occurred with the laryngeal mask airway and seven with the tracheal tube. There were no deaths related to pulmonary aspiration. The incidence and outcome of pulmonary aspiration detected in this study were similar to those previously reported. The adjusted odds ratio (OR) for pulmonary aspiration with the laryngeal mask airway was 1.06 (95% CI 0.20–5.62). Unplanned surgery (OR 30.5, 95% CI 8.6–108.9) and male sex (OR 8.6, 95% CI 1.1–68) were associated with an increased risk of aspiration and age < 14 years with a reduced risk (OR 0.21, 95% CI 0.07–0.64). There were contraindications and exclusions to the use of the laryngeal mask airway but in this selected population the use of an laryngeal mask airway was not associated with an increased risk of pulmonary aspiration compared with a tracheal tube.
...... Correspondence to: Dr Giuseppe Natalini E-mail: [email protected], [email protected] Accepted: 14 August 2009
The laryngeal mask airway (LMA) has several advantages ventilation. The aim of the present study was to test the over tracheal intubation in patients undergoing general hypothesis that using an LMA increases the risk of anaesthesia. Postoperative hoarseness, sore throat, impair- pulmonary aspiration compared with tracheal intubation ment of swallowing, pain, nausea and vomiting, and in patients undergoing positive pressure ventilation. coughing are reduced, post-anaesthesia recovery unit length of stay is shortened, and increases in intra-ocular Methods pressure and derangements in cardiovascular and respira- tory function are less likely [1–11]. Furthermore, the The study design was a retrospective analysis of prospec- LMA can be useful in the management of the difficult tively collected data. The analysis was conducted on the airway when facemask ventilation is inadequate [12]. anaesthesia database of Poliambulanza Foundation Despite its advantages, concerns exist over the safe use Hospital (a university affiliated not for profit hospital). of the LMA and its ability to prevent pulmonary The institutional ethics committee (Comitato Etico Isti- aspiration [13]. Positive pressure ventilation may be a tuzioni Ospedaliere Cattoliche) approved the data analysis. risk factor for pulmonary aspiration with the LMA [14] The database is constructed as follows: anaesthetists fill secondary to gastric inflation [15–18]. out structured file cards with data relating to their Safety is an important anaesthetic issue with significant anaesthetic procedures. The departmental assistant then clinical and legal implications. Not surprisingly, pulmo- checks and enters file cards into the electronic anaesthesia nary aspiration is a key factor when considering the role database on a daily basis. The database records have the of supraglottic airway devices [19]. There is little evidence following fields: procedure-related information (day of evaluating the risks of pulmonary aspiration with an LMA surgery, surgical specialty, type of procedure, length compared with tracheal intubation during mechanical of surgery, if surgery was elective or unplanned);