Atypical Sleep and Postoperative Delirium in the Cardiothoracic Surgical Intensive Care Unit: A Pilot Prospective Study

Abstract

Purpose

Postoperative delirium (POD) is a very common and serious neurological complication in patients admitted to the cardiothoracic surgical intensive care unit (CSICU). We aimed to identify a novel potential sleep-based marker for POD and investigate the relevance between atypical sleep and POD.

Patients and Methods

This was a prospective, observational study of patients admitted to the CSICU between December 2019 and February 2020 at our center. Sleep characteristics from 21:00 on postoperative day 1 to 07:00 on postoperative day 2 were assessed using polysomnography (PSG). POD from the end of PSG monitoring until postoperative day 5 was evaluated using the Confusion Assessment Method for the Intensive Care Unit.

Results

This analysis included 20 patients admitted to the CSICU. The incidence of atypical sleep was 45.0%. Compared to patients without delirium, those with delirium had less delta power, less percentage REM sleep, and a higher proportion of atypical sleep and REM sleep loss (P < 0.05).

Conclusion

The presence of atypical sleep and the absence of REM sleep were associated with POD in patients admitted to the CSICU.

Keywords:

• postoperative delirium
• intensive care unit
• atypical sleep
• cardiac surgery

Ethics Approval and Informed Consent

All procedures performed in this study were in accordance with the ethical standards of the Union Hospital, Fujian Medical University and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants included in the study.

Acknowledgments

The authors thank the Department of Neurology and Sleep Medicine of Fujian Medical University Union Hospital for providing PSG technical support and the Heart Medicine Research Center of Fujian Medical University Union Hospital for providing study site. Yanjuan Lin and Liang-Wan Chen are co-corresponding authors.

Disclosure

The authors report no conflicts of interest in this work.

Additional information

Funding

This work was supported by the Joint Finds for the Innovation of Science and Technology, Fujian province (Grant number: 2017Y9052) and the Guiding Project of Fujian Science and Technology (2017Y0038).