Postoperative use of high flow nasal insufflation for obstructive sleep apnea.

BACKGROUND: Continuous positive airway pressure (CPAP) therapy is the gold standard treatment for obstructive sleep apnea (OSA), although, associated with poor patient compliance. Conversely, high flow, humidified, temperature-regulated nasal insufflation of oxygen or air is well tolerated. CASE: We describe our experience of three patients with known or suspected moderate to severe OSA who were poorly compliant to CPAP therapy and received high flow nasal insufflation (HFNI) postoperatively. None had significant episodes of desaturation (SpO2 < 95%) and all patients uniformly reported superior comfort levels than with the CPAP therapy. HFNI generates small amounts of positive end-expiratory pharyngeal pressure, increases inspiratory airflow and decreases dead space ventilation. Due to the open system, less difficulty with the patient-mask interface and improved patient comfort is experienced. These factors help prevent hypopnea and lead to enhanced sleep continuity. CONCLUSIONS: HFNI may be a promising alternative to CPAP therapy in the perioperative setting.

Facilitating Airway Surgery in a Morbidly Obese Patient Using Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE).

Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) is a relatively new noninvasive oxygenation technique with a broad range of applications. It is used in the treatment of type one respiratory failure, as a preoxygenation tool, as a rescue and temporising measure in difficult airways, and as step-down oxygen therapy in patients after extubation. Its use has also been described in laryngeal surgeries, but they mainly involved normal-weight subjects or were used as a bridging oxygenation therapy before definitive airway is secured. The major benefits of using THRIVE in obese subjects undergoing laryngeal surgery include a tubeless and uninterrupted surgical field. This advantage is especially crucial in obese patients as they tend to have limited oropharyngeal space, rendering a shared airway technically challenging for surgeons. However, concerns of potential difficult airway and shorter safe apnoeic time in the obese population limit its use. In this case, we report its use as the sole oxygenation strategy in a morbidly obese patient undergoing airway surgery. Our experience suggests that THRIVE can provide a conducive operating field and adequate oxygenation in short apnoeic laryngeal procedures in the obese population, without causing excessive hypercarbia.

A bench study comparing between scalpel-bougie technique and cannula-to-Melker technique in emergency cricothyroidotomy in a porcine model.

BACKGROUND: The ideal emergency cricothyroidotomy technique remains a topic of ongoing debate. This study aimed to compare the cannula-to-Melker technique with the scalpel-bougie technique and determine whether yearly training in cricothyroidotomy techniques is sufficient for skill retention. METHODS: We conducted an observational crossover bench study to compare the cannula-to-Melker with the scalpel-bougie technique in a porcine tracheal model. Twenty-eight anesthetists participated. The primary outcome was time taken for device insertion. Secondary outcomes were first-pass success rate, incidence of tracheal trauma, and technique preference. We also compared the data on outcome measures with the data obtained in a similar workshop a year ago. RESULTS: The scalpel-bougie technique was significantly faster than the cannula-to-Melker technique for cricothyroidotomy (median time of 45.2 s vs. 101.3 s; P = 0.001). Both techniques had 100% success rate within two attempts; there were no significant differences in the first-pass success rates and incidence of tracheal wall trauma (P > 0.999 and P = 0.727, respectively) between them. The relative risks of inflicting tracheal wall trauma after a failed cricothyroidotomy attempt were 6.9 (95% CI 1.5-31.1), 2.3 (95% CI 0.3-20.7) and 3.0 (95% CI 0.3-25.9) for the scalpel-bougie, cannula-cricothyroidotomy, and Melker-Seldinger airway, respectively. The insertion time and incidence of tracheal wall trauma were lower when the present data were compared with data from a similar workshop conducted the previous year. CONCLUSIONS: This study supports the use of a scalpel-bougie technique for cricothyroidotomy by anesthetists and advocates a yearly training program for skill retention.