A Preliminary Study on the Utility of Root® with SedLine® for Sleep Evaluation in Critically Ill Patients: Comparison With Polysomnography and the Richards−Campbell Sleep Questionnaire

Abstract Background To date, there has not been a practical evaluation of patient sleep in critical care units, where sleep disturbance is commonly found. This study aimed to validateฎ a portable electroencephalography monitor, as a sleep monitoring device, against polysomnography (PSG) for objective sleep evaluation and the Richards − Campbell Sleep Questionnaire (RCSQ) for subjective sleep quality in critically ill patients.Methods In this observational study, the sleep pattern of 10 adult patients staying in an ICU for at least 72 hours was evaluated for 24 hours using PSG and the Patient State Index (PSI) from SedLine. Additionally, their nighttime sleep was subjectively scored using the RCSQ to compare with the objective parameters.Results Sleep architecture from PSG showed an increase in light sleep and a prominent decrease in restorative sleep, despite preserved quantity of nocturnal sleep. Based on PSG results, PSI was distributed in accordance with sleep depth. Subjective quality of nocturnal sleep from the RCSQ was correlated with the PSI (r = -0.816, 95% confidence interval [CI]: -0.955 to -0.383), as well as with the nighttime stage N2 ratio from PSG alone (r = 0.741, 95% CI: 0.209 to 0.935) or combined with restorative sleep (r = 0.801, 95% CI: 0.347 to 0.951). The cutoff value of PSI to distinguish between the stage N1 and N2 was 67.0 (specificity, 0.641; sensitivity, 0.845 with area under curve [AUC] of 0.818).Conclusion SedLine is considered a feasible and valid instrument for sleep quality assessment in ICU patients.Trial registration: This investigation was part of an interventional trial registered with the University Hospital Medical Information Network Individual Clinical Trials Registry (UMIN-CTR000026350, http://www.umin.ac.jp/icdr/index-j.html) on March 1, 2017.