Effects of mechanical ventilation on sleep of patients in the intensive care unit

Objective To study the effects of mechanical ventilation on sleep duration and sleep fragmentation of patients in the intensive care unit.Methods Fifty patients in the intensive care unit(ICU) were assigned to a control group(spontaneous breathing without tracheal intubation) and experimental group(spontaneous breathing or mechanical ventilation under tracheal intubation).The experimental groups were sedated with different doses of midazolam and were subsequently divided into T0 group(spontaneous breathing under tracheal intubation,without sedation),Ts group(low dose midazolam and mechanical ventilation under tracheal intubation),Tm1 group(low dose midazolam and mechanical ventilation under tracheal intubation),and Tm2 group(high dose midazolam and mechanical ventilation under tracheal intubation).Polysomnography was used to detect the sleep duration and sleep fragmentation from 22:00 to 6:00 on the next day in all patients.Results Compared with control group,patients in other groups,except for Ts group,had significantly shorter sleep duration and significantly more sleep fragmentations(P0.01).Compared with patients in T0,those in Ts had significantly shorter total sleep time([171±85] vs.[296±87],P0.01) and significantly more sleep fragmentations( vs.,P0.01);compared with patients in Ts,those in Tm1 group had significantly shorter sleep time([296±87] vs.[165±68],P0.01) and significantly more sleep fragmentations( vs.,P0.01).Conclusion Mechanical ventilation patients have shorter sleep duration and more sleep fragmentations,and high-dose-sedation may prolong the sleep duration and reduce sleep fragmentations in these patients.(Shanghai Med J,2010,33: 132-135)