Sleep after critical illness: Study of survivors of acute respiratory distress syndrome and systematic review of literature

BACKGROUND AND AIMS: This study aims to evaluate the sleep quality, architecture, sleep-related quality of life, and sleep-disordered breathing (SDB) in acute respiratory distress syndrome (ARDS) survivors early after discharge. MATERIALS AND METHODS: In this prospective, observational study, consecutive patients with ARDS discharged from the Intensive Care Unit (ICU) underwent evaluation with Epworth sleepiness scale (ESS), Pittsburgh Sleep Quality Index (PSQI), Functional Outcomes of Sleep Questionnaire (FOSQ), and overnight polysomnography. Patients having one or more of the following characteristics were classified as having abnormal sleep: ESS>10, PSQI>5, FOSQ <17.9, apnea–hypopnea index (AHI) ≥5, or AHI during rapid eye movement (REM) sleep ≥5. RESULTS: Twenty patients (median interquartile range [IQR] age of 24 [22–28] years, 11 [55%] females) were included in the study. Acute febrile illness of unknown etiology with multi-organ dysfunction syndrome was the most common underlying etiology for ARDS. The median (IQR) PaO(2)/FiO(2) ratio and APACHE II scores on admission were 176 (151–191.5) and 14 (14–16), respectively. The median (IQR) duration of stay in the ICU was 10 days (7.3–19.5). The overall sleep efficiency (median [IQR], 54% [32.3–65.4%]) was poor. None of the patients had ESS>10, seven (35%) had global PSQI>5 and one had FOSQ <17.9. Ten (50%) patients had at least one characteristic that suggested abnormal sleep (4 insomnia, 2 central sleep apnea, 1 obstructive sleep apnea, 1 REM-SDB, and 2 with a high PSQI, but no specific sleep abnormality). CONCLUSIONS: Sleep disturbances are common in ARDS survivors early after discharge from the ICU.