Efeitos agudos da ventilação não invasiva na fisiologia do sono em pacientes com doença pulmonar obstrutiva crônica moderada a grave estáveis

Abstract

Changes in sleep architecture in patients with Chronic Obstructive Pulmonary Disease (COPD) can be explained by the combination of physiological changes in breathing during sleep with impairment respiratory mechanics and reduction of arterial oxygenation observed in these patients. Nocturnal noninvasive ventilation (NIV) promotes effects on reducing alveolar hypoventilation, improving sleep quality, quality of life, and reducing mortality. This study aimed to evaluate the acute effects of noninvasive ventilation (NIV), compared to spontaneous breathing, on sleep latency and stages, and on the occurrence of sleep-related respiratory events, nocturnal hypoxemia, and changes in heart rate (HR) in patients with moderate to severe stable COPD. This was a physiological study, developed at the Laboratory of the Respiration of the Federal University of Ceara, from October 2017 to September 2019. Patients completed two polysomnography (PSG) studies: one during spontaneous breathing and one while receiving NIV, with the ventilatory parameters individually adjusted in a bilevel mode, S/T, EPAP = 5.9 ± 1.7 cmH2O, IPAP = 14.2 ± 2.9 cmH2O and a backup respiratory rate = 11.5 ± 1.5 rpm. Sleepware G3 software was used for the analysis of PSG and pressure, volume and flow curves x time. Participants were 10 female patients with a mean age of 68.1 ± 10.2 years. NIV during sleep, compared to spontaneous respiration, decreased sleep onset latency (17 ± 18.8 min vs 46.8 ± 39.5 min; p = 0.02); increased REM sleep time (41.2 ± 24.7 min vs 19.7 ± 21.7 min; p = 0.03) and decreased the obstructive apnea index (OAI) (0 vs 8.7 ± 18.8; p = 0.01). Lower mean HR (66.6 ± 4.1 bpm vs 70.6 ± 5.9 bpm; p = 0.03) and lower maximum HR (84.1 ± 7.3 bpm vs 91.6 ± 7.8 bpm; p = 0.03) were observed in PSG with NIV. The use of NIV in patients with moderate to severe stable COPD, while they were sleeping, increased REM sleep time and decreased sleep onset latency, the number of obstructive respiratory events, and the mean and maximum HR.