Background: Morbidly obese patients are at risk of hypoxemia at the time of induction of anesthesia. The aim of this study was to assess the possible increase in the safe apnea time with the use of ProSeal laryngeal mask airway (PLMA) as a conduit prior to laryngoscope-guided intubation in morbidly obese patients undergoing surgery under general anesthesia.
Methods: Hundred patients with BMI greater than 35 kg/m2, undergoing surgery under general anesthesia, were randomly divided to receive either PLMA or facemask with oropharyngeal airway (FM) as the airway device. Following preoxygenation with 100% oxygen with continuous positive airway pressure of 10 cm H2O, in ramp position for 5 min the patients were made apneic. From start of apnea to the time to reach SpO2 to 92% was recorded as safe apnea time. Ventilation was initiated and time to reach SpO2 of 100% was recorded as recovery time.
Results: The mean safe apnea time was 205 (96-320)s in FM vs. 337 (176-456) s in PLMA (P = 0.0000). The mean recovery period was 49 (36-68)s in FM vs. 42(30-56)s in PLMA groups (P = 0.0000). Arterial blood gas analysis showed significant difference in pO2 between the two groups.
Conclusion: The use of ProSeal laryngeal mask airway prior to laryngoscope-guided intubation is beneficial in increasing safe apnea period and achieving faster recovery from hypoxemia in morbidly obese patients.