Apneic oxygenation during prolonged laryngoscopy in obese patients: a randomized, controlled trial of nasal oxygen administration

Abstract

Study objective: To evaluate the influence of nasal oxygen (O(2)) administration on the duration of arterial oxygen saturation (SpO(2)) >or=95% during simulated difficult laryngoscopy in obese patients.

Design: Prospective, randomized, controlled trial.

Setting: University hospital.

Patients: 30 obese men undergoing general anesthesia.

Interventions: After thorough preoxygenation, and using total intravenous anesthesia, simulated difficult laryngoscopy was performed, with half the patients receiving additional nasal O(2) during apnea.

Measurements: Duration of SpO(2) >or=95% was measured up to a maximum of 6 minutes. Lowest SpO(2) values and time to regain 100% SpO(2) (resaturation time) also were recorded.

Main results: Nasal O(2) administration was associated with significant prolongation of SpO(2) >or=95% time (5.29 +/- 1.02 vs. 3.49 +/- 1.33 min, mean +/- SD), a significant increase in patients with SpO(2) >or=95% apnea at 6 minutes (8 vs. one pt), and significantly higher minimum SpO(2) (94.3 +/- 4.4% vs. 87.7 +/- 9.3%). Resaturation times were no different between the groups.

Conclusions: Nasal O(2) administration is associated with significant increases in frequency and duration of SpO(2) >or=95%, and higher minimum SpO(2) during prolonged laryngoscopy in obese patients.