Average volume-assured pressure support versus conventional bilevel pressure support in pediatric nocturnal hypoventilation: a case series.

Abstract

STUDY OBJECTIVES\nAverage volume-assured pressure support (AVAPS) is a modality of non-invasive ventilation (NIV) that provides a targeted tidal volume by automatically adjusting the inspiratory pressure support within a set range. Pediatric studies evaluating the efficacy of AVAPS in treating nocturnal hypoventilation are confined to case reports. The aim of this study was to compare AVAPS to conventional bilevel positive airway pressure (BPAP) support in improving hypercarbia in a cohort of pediatric patients with nocturnal hypoventilation.\n\n\nMETHODS\nRetrospective review of patient records at an established tertiary pediatric sleep laboratory over a six-year period. Ventilatory and sleep study parameters from AVAPS and conventional BPAP titration studies were compared. AVAPS was used only if hypoventilation was not controlled using conventional BPAP. Inspiratory pressures, tidal volumes and compliance were downloaded on final titrated ventilatory settings. Comparisons were made using paired t-test.\n\n\nRESULTS\nA total of 19 patients (11 males, 8 females; median age 10.5 years, range 1 to 20 years) were identified. Diagnoses included: neuromuscular disease (n=9), obstructive hypoventilation (n=5), parenchymal lung disease (n=4) and congenital central hypoventilation syndrome (n=2). AVAPS demonstrated significant improvement in peak (p=0.009) and mean (p=0.001) TcCO₂ parameters compared to conventional bilevel. Oxygenation on AVAPS showed positive trend but did not reach statistical significance. AVAPS delivered higher tidal volumes (p=0.04) using similar pressures. There was no statistically significant difference in OAHI, respiratory arousal index, sleep efficiency and compliance between AVAPS and conventional BPAP.\n\n\nCONCLUSIONS\nAVAPS was an effective alternative to conventional BPAP in improving hypercarbia in our selective cohort of pediatric patients. Prospective, longitudinal studies are needed to evaluate the benefits of AVAPS feature in the pediatric population.