Apneic Oxygenation During Prolonged Laryngoscopy in Obese Patients: A Randomized, Controlled Trial of Buccal RAE Tube Oxygen Administration.

BACKGROUND: Despite optimal preoxygenation, obese patients undergoing induction of general anesthesia exhibit significant hypoxemia after 2 to 4 minutes of apnea. Apneic oxygenation techniques can assist airway management by extending the safe apnea time. We hypothesized that a novel method of apneic oxygenation via the oral route would effectively prolong safe apnea in an obese surgical population. METHODS: In this open-label, parallel-arm, randomized-controlled efficacy trial, 40 ASA physical status I-II obese patients with body mass index (BMI) 30-40 were randomly assigned to standard care (n = 20) or buccal oxygenation (n = 20) during induction of total IV anesthesia. Buccal oxygen was administered via a modified 3.5-mm Ring-Adair-Elwyn (RAE) tube apposed to the left internal cheek. Prolonged laryngoscopy maintained apnea with a patent airway until SpO2 dropped below 95% or 750 seconds elapsed. The primary outcome was time to reach SpO2 < 95%. RESULTS: Patient characteristics were similar in both study arms. Recipients of buccal oxygenation were less likely to exhibit SpO2 < 95% during 750 seconds of apnea; hazard ratio 0.159 (95% confidence interval 0.044-0.226, P < .0001). Median (interquartile range [IQR]) apnea times with SpO2 ≥ 95% were prolonged in this group; 750 (389-750) versus 296 (244-314) seconds, P < .0001. CONCLUSIONS: Clinically important prolongation of safe apnea times can be achieved delivering buccal oxygen to obese patients on induction of anesthesia. This novel use of apneic oxygenation via the oral route may improve management of the difficult airway and overcome some of the limitations of alternative techniques.

The 'Can't intubate can't oxygenate' scenario in pediatric anesthesia: a comparison of the Melker cricothyroidotomy kit with a scalpel bougie technique.

BACKGROUND: While the majority of pediatric intubations are uncomplicated, the 'Can't intubate, Can't Oxygenate' scenario (CICO) does occur. With limited management guidelines available, CICO is still a challenge even to experienced pediatric anesthetists. OBJECTIVES: To compare the COOK Melker cricothyroidotomy kit (CM) with a scalpel bougie (SB) technique for success rate and complication rate in a tracheotomy on a cadaveric 'infant airway' animal model. METHODS: Two experienced proceduralists repeatedly attempted tracheotomy in eight rabbits, alternately using CM and SB (4 fr) technique. The first attempt was performed at the level of the first tracheal cartilage with subsequent experimental trials of insertion progressively more caudad. Success was defined as intratracheal placement of cannula as seen on bronchoscope. Complications were assessed both by bronchoscopic and macropathological appearance. RESULTS: 32 attempts were made at tracheotomy. CM had an overall success rate of 100% compared to a 75% success rate for SB. Success rate for the first attempt was dependent on the level of the tracheotomy (Level 1 100%, level 2 62.5% and level 3 & 4 25%). While CM was associated with lateral and/or posterior wall damage on bronchoscopy/macropathology in 6% of 19% and 25% of 50% respectively, the damage observed was greater and more frequent with SB (19%/44% and 31%/50%, respectively). CONCLUSIONS: At level 1, the first attempt success rate was 100% for both devices. Overall CM showed a better success rate than SB; however, both techniques were associated with significant complication rates, which were more pronounced following the scalpel bougie technique.