Background: Sleep disruptions frequently occur in hospitalized patients, especially with critically ill, mechanically ventilated patients. Severely altered sleep architectures result in unclassifiable sleep stages as listed by the conventional Rechtschaffen and Kales (R&K) criteria, and a new classification for sleep scoring including atypical sleep (AS) and pathological wakefulness (PW) has recently been proposed.

Objective: To demonstrate the feasibility of performing objective sleep qualification in patients receiving mechanical ventilation due to acute respiratory failure.

Materials and Methods: In the present prospective cohort study, polysomnography was performed in 38 patients requiring invasive mechanical ventilation due to acute respiratory failure at the respiratory care unit (RCU) of Siriraj Hospital between February and December 2017. Their sleep stages were analyzed by conventional rules and the new classifications of AS and PW. The associations between the presence of AS or PW and the patients’ characteristics were analyzed. Correlations between sleep quality and clinical parameters were also determined.

Results: Most of the patients had poor sleep quality with median sleep efficiency (IQR) of 35.9% (18.5, 62.3) and significantly decreased slowwave sleep [median (IQR) 0.4% (0.00, 5.70)] and REM [median (IQR) 1.3% (0.00, 6.43)]. According to the new classifications, 14 out of 38 (prevalence of 36.8%) mechanically ventilated patients had AS. The prevalence of PW and either AS or PW were 36.8% and 52.6%, respectively. A higher baseline respiratory rate was observed among patients who had either AS or PW at 24 versus 20 breaths/minute (p=0.02), while a longer duration of mechanical ventilator support was found in patients with PW at nine versus five (p=0.003). Patient-ventilator asynchrony was also noted in all patients.

Conclusion: Sleep quality among critically ill and mechanically ventilated patients was severely disturbed. A higher prevalence of AS and PW were noted. The technical feasibility of sleep recording in Thai intensive care unit (ICU) settings was established.

Keywords: Polysomnography, Atypical sleep, ICU

DOI: doi.org/10.35755/jmedassocthai.2021.02.11960

Received 14 September 2020 | Revised 28 September 2020 | Accepted 29 September 2020