Does using pressure-controlled ventilation to rest respiratory muscles improve sleep in ICU patients?

Purpose: Sleep is commonly altered in critically ill patients. Ventilatory mode may impact on quality of sleep. The aim of our study was to evaluate the effect on sleep of pressure-controlled ventilation (PCV) to spontaneous ventilation with 6 cm H2O inspiratory pressure (low-PSV). Methods: Thirty-five patients intubated and mechanically ventilated for acute-on-chronic respiratory failure were included in this prospective randomized cross-over study. Nine were discarded, 13 received PCV first (10 p.m.-2 a.m.) and then low-PSV (2-6 a.m.) and 13 patients received low-PSV first and then PCV. Results: Sleep architecture was altered (50.4% of the night was spent in wakefulness). PCV was associated with significantly improved sleep quality and quantity compared to low-PSV: sleep efficiency (total sleep time/total recording time) was 63% (range: 9-100) vs. 37% (0-96; p = 0.0002), stage 2 NREM sleep was 33% vs. 13% (p = 0.0005), stages 3 and 4 NREM sleep were 9% vs. 3.5% (p = 0.003) and REM sleep was 6.5% vs. 0% (p = 0.003). Conclusions: Sleep quantity and quality were significantly improved with PCV compared to low-PSV. Nocturnal respiratory muscles rest through PCV is recommended to improve sleep in ICU patients with acute-on-chronic respiratory failure