New Suggested Enhancing Safe Apneic Time in Edentulous Elderly: A Comparison of Transnasal Humidified Rapid-Insufflation Ventilatory Exchange and Facemask.

ABSTRACT

BACKGROUND Edentulous elderly patients often face challenges in airway management and are susceptible to hypoxemia. Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) provides high-flow nasal oxygenation, potentially extending safe apneic time (SAT). This study compared the efficacy of THRIVE versus facemask ventilation in improving oxygenation and extending SAT in edentulous elderly patients. MATERIAL AND METHODS Patients with more than 10 missing teeth and who were over 65 years old were randomly assigned to the facemask group (Group M, n=25) or the THRIVE group (Group T, n=25). Patients in Group M were pre-oxygenated with a facemask (6 L/min, FiO2 100%), while patients in Group T were pre-oxygenated with their mouths closed via THRIVE (30 L/min, FiO2 100%). After anesthesia induction, patients in Group M were ventilated with pressure-controlled ventilation. In Group T, the patient's mouth was kept closed, and the flow rate was adjusted to 70 L/min. Four min after cisatracurium administration, ventilation was stopped in Group M while Group T continued to receive oxygen (70 L/min, FiO2 100%).The primary outcome was SAT, which was attained at 4 min after injection of cisatracurium and ended when SpO2 decreased to 95% or when apneic time reached 480 s. A secondary outcome was the reoxygenation time, defined as the time from the beginning of mechanical ventilation to the time when SpO2 98% was reached. RESULTS An SAT of 480 s was reached by all patients in Group T, but by only 6 patients in Group M (P<0.05). Compared with Group M, the reoxygenation time in Group T was significantly shorter (P<0.05). CONCLUSIONS As compared to facemask, THRIVE can extend the SAT, improve oxygenation, and reduce reoxygenation time.