Analysis of polysomnography in elderly patients in surgical intensive care unit

Abstract

Objective To evaluate the sleep quality and architecture of postoperative elderly patients without mechanical ventilation in surgical intensive care unit(SICU). Methods The polysomnography(PSG) were recorded and analyzed from fifty elderly patients in SICU(case group) and forty non-surgical physical examination elderly(control group) by using Australian Compumedics Siesta. Results Compared control group, the case group had less total sleep time[289.5 min(147.5-398.8 min) vs 218.4 min(125.3-345.7 min)](P<0.05), poor sleep efficiency[48.2%(24.6%-66.5%) vs 36.3%(20.8%-57.6%)](P<0.05). PSG showed that stage-1 sleep was dominant in the case group[67.3%(21.6%-78.3%)] and stage-2 sleep was dominant in control group [59.6%(18.2%-73.2%)]. The case group had less deep sleep than control group[18.3%(4.1%-20.9%) vs 7.9%(0-11.4%)](P<0.05). The postoperative sleep of case group were absent rapid eye movement (REM) and seventy-six percent were absent slow wave sleep(SWS). Meanwhile only six elderly patients had no REM and five elderly had no SWS in control group. The postoperative sleep of case group were more broken and more frequently aroused than control group[9.1 bph(4.8-24.3 bph) vs 20.5 bph(8.8-32.2 bph)](P<0.01). Conclusions Postoperative elderly patients are more vulnerable to sleep disorder and disturbance and shows the significant decrease of total sleep time, absence of deep sleep, fragmented sleep and frequently aroused. Key words: Postoperative; Elderly patient; Sleep; Polysomnography