Laryngo-pharyngeal complaints following laryngeal mask airway and endotracheal intubation.

STUDY OBJECTIVE: To investigate the incidence and severity of laryngo-pharyngeal complaints following anesthesia with the use of a laryngeal mask airway (LMA) compared with endotracheal intubation in adults.

DESIGN: Prospective study with randomized patient selection.

SETTING: University medical center.

PATIENTS: 202 adult ASA physical status I, II, and III patients scheduled for elective surgery of either an extremity or breast, or a transurethral resection.

INTERVENTIONS: Following intravenous induction of anesthesia, a standard LMA size #3, #4, or #5 corresponding to the patient's body weight, was inserted in 103 patients; 99 patients were intubated with a polyvinylchloride endotracheal tube [7.5 mm inner diameter (ID) in women and 8.0 mm ID in men]. Cuff pressures in the LMA group were initially reduced to a minimum pressure at which an air-tight seal between the LMA and the laryngeal inlet was provided at a positive pressure of 20 cm H2O during manual bag ventilation. Cuffs of endotracheal tubes were inflated and controlled to a volume needed to prevent gas leak at 35 cm H2O pressure.

MEASUREMENTS AND MAIN RESULTS: Cuff pressures were continuously monitored in both groups. Patients assessed their laryngo-pharyngeal complaints on a 101-point numerical rating scale on the evening after surgery and the following two days. No difference was found in the incidence and severity of sore throat on the evening following surgery or on the two following days. Dysphonia was more frequent following intubation than following LMA insertion on the day of surgery (46.8% vs. 25.3%) and on the first postoperative day (28.1% vs. 11.6%) (p < 0.05). However, the incidence of dysphonia increased with the duration of anesthesia in LMA patients but not in intubated patients. The incidence of dysphagia was significantly higher following LMA insertion compared with endotracheal intubation on the day of surgery (23.8% vs. 12.5%), and on the first postoperative day (22.3% vs. 10.4%). The severity of the individual complaints of minor laryngo-pharyngeal morbidity was comparable between groups. The type of airway management during anesthesia did not affect patient satisfaction with the anesthesia received.

CONCLUSIONS: There is a distinct pattern of laryngo-pharyngeal complaints following the use of the LMA and endotracheal intubation. With regard to minor laryngo-pharyngeal morbidity, the advantage of the LMA to endotracheal intubation is questionable.