Synchronized mandibular movement and capnography: a novel approach to obstructive airway detection during procedural sedation—a post hoc analysis of a prospective study

Abstract

Perioperative complications related to obstructive sleep apnea still occur despite the use of partial pressure end-tidal CO₂$\left( {{{\text{P}}_{{\text{ETC}}{{\text{O}}_2}}}} \right)$ and pulse oximetry. Airway obstruction can complicate propofol sedation and a novel monitor combining mandibular movement analysis with capnography may facilitate its detection. Patients scheduled for sleep endoscopy were recruited and monitored with standard monitoring, ${{\text{P}}_{{\text{ETC}}{{\text{O}}_2}}},$ and Jaw Activity (JAWAC) mandibular movement sensors. A post hoc analysis investigated airway obstruction prediction using a Respiratory Effort Sequential Detection Algorithm (RESDA) based on ${{\text{P}}_{{\text{ETC}}{{\text{O}}_2}}}$ and mandibular movement signals. 21 patients were recruited and 54 episodes of airway obstruction occurred. RESDA detected obstructive apnea [mean ± SD (median)] 29 ± 29 (21) s, p < 0.0001, before ${{\text{P}}_{{\text{ETC}}{{\text{O}}_2}}}$ alone. This prolonged the time between obstructive apnea detection and decrease to 90% oxygen saturation 64 ± 38 (54) versus 38 ± 20 (35) s, p < 0.0001. It predicted airway obstruction with a sensitivity and specificity of 81% and 93%, respectively. The RESDA algorithm, which is based on the combination of capnography with mandibular movement assessment of respiratory effort, can more rapidly alarm anesthetists of airway obstruction during propofol sedation than ${{\text{P}}_{{\text{ETC}}{{\text{O}}_2}}}$ alone. However, ${{\text{P}}_{{\text{ETC}}{{\text{O}}_2}}},$ pulse oximetry, and clinical monitoring are still required.

Trial Registry numbers: ClinicalTrial.gov (NCT02909309) https://clinicaltrials.gov/ct2/show/NCT02909309.