Diagnostic value of photoplethysmography for obstructive sleep apnea syndrome in critically ill patients

Objective To investigate the diagnostic value of photoplethysmography (PPG) in the detection of obstructive sleep apnea syndrome (OSAS) among critically ill patients with respiratory or cardiocerebrovascular diseases accompanied by snoring.

Methods A total of 91 critically ill patients with respiratory or cardiocerebrovascular diseases accompanied by snoring, admitted to the internal medicine ward of Subei People's Hospital from January 2019 to October 2023 were enrolled. After informed consent, overnight polysomnography (PSG) and PPG were performed. The consistency of the sleep apnea parameters obtained of the two methods by sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristic (ROC) curve.

Results There were no statistically significant differences in apnea-hypopnea index (AHI), total sleep time, lowest oxygen saturation, and time with oxygen saturation below 90% between PPG and PSG (P>0.05). When AHI≥ 5 times/h and AHI≥15 times/h, the diagnostic sensitivity of the patients in this group was 94.37% and 93.10%, respectively, with specificities of 73.68% and 90.91%, positive predictive values of 91.78% and 94.74%, and negative predictive values of 77.78% and 88.23%, and areas under the ROC curves were 0.961 and 0.982, respectively. For critically ill patients with respiratory diseases, the diagnostic sensitivity was 89.29% and 87.10%, respectively, with specificities of 84.62% and 80.00%, positive predictive values of 92.59% and 93.10%, and negative predictive values of 78.57% and 72.72%, and the areas under the ROC curves were 0.978 and 0.987, respectively. For critically ill patients with cardiocerebrovascular diseases, the diagnostic sensitivity was 87.18% and 90.32%, respectively, with specificities of 83.33% and 89.47%, positive predictive values of 91.89% and 99.63%, and negative predictive values of 78.57% and 85.56%, and the areas under the ROC curves were 0.942 and 0.986, respectively.

Conclusion PPG monitoring results show high consistency with PSG in critically ill patients with respiratory and cardiocerebrovascular diseases combined with OSAS.