Sleep in Critically III Chemically Paralyzed Patients Requiring Mechanical Ventilation: Results
There was no statistical difference in delta activity for staging slow-wave sleep (SWS) between the two methods (p = 0.96). The Rechtschaffen and Kales scoring criteria resulted in 0%, 1%, and 5% reductions in staging SWS in the IS, CS, and CS/ NMBA groups, respectively. Further results are reported using the mDelta data. Fifty percent of the subjects in the CS group had > 80% mDelta activity, and the other 50% had < 8% mDelta. In the group receiving NMBA, only two subjects had < 30% mDelta activity. In the IS group, only one patient had > 30% mDelta activity that was also associated with superimposed a activity. This patient had the highest LIS, sedation, and narcotic dosage in the IS group. REM sleep was severely diminished in the IS group (3.6% TST) [Table 3]. fully
Data were not analyzed further, as only 50% of patients receiving CS had detectable REM and no REM was detectable in the patients receiving NMBA.
Sleep Fragmentation: Arousals and Awakening Between Groups: Twenty-four-hour sleep efficiency was increased in all groups (data not shown), but the 8-h nocturnal sleep efficiency was 40%, 49%, and 70% in the IS, CS, and CS/NMBA groups, respectively. This indicates a substantial proportion of sleep occurred during the daytime. The CS and CS/ NMBA groups had less wake time than the IS group (Table 3). Patients receiving NMBA spent 22% of the sleep period awake. There was an increasing trend in the arousal index and awakenings in the CS/NMBA group; however, there was no statistical difference between groups (Table 3) or when compared to normative values (10/h). The number of patient-care interventions differed between the groups (Table 3). Patients in the IS group had fewer interventions than the CS/NMBA group, and there was a trend with increasing interventions in the CS/NMBA group compared to the CS group (p = 0.06). However, there was no correlation between the total number of interventions per patient in each group with the number of arousals or awakenings per patient.
Correlation With Severity of Illness Scores, and Clinical and Laboratory Indexes: There was no statistical significant correlation between TST, any specific sleep stage, arousal index, or days in the ICU with LIS or APACHE II scores. As expected, LIS and APACHE II scores were significantly correlated (r2 = 0.65, p = 0.003). There was no significant correlation between positive or negative culture results (all sources) and any stage of sleep.
Category: Respiratory Symptoms
Tags: ICU, mechanical ventilation, polysomnography, sleep