Overnight pulse oximetry (OPO) has proven to be an effective and beneficial technique to determine the cardiorespiratory status of patients in both the inpatient and outpatient settings. It is a cheap, safe, reliable, simple, and accurate method of patient monitoring as compared to the expensive and labor-intensive method of multichannel polysomnography for detecting sleep-disordered breathing. It provides accurate information about patient’s oxygenation status and also helps in monitoring the response to continuous positive airway pressure and in the surgical treatment of obstructive sleep apnea (OSA).
Overnight pulse oximetry (OPO)
Nocturnal pulse oximetry is a low-cost, safe, simple, convenient, noninvasive, and effective screening method for SDB in adults. It is readily and easily accessible with no risks or side effects to the patients and has decreased the waiting time of OSA diagnosis.
Apnea and hypopnea cause an arousal from sleep causing sympathetic activation, sleep disruption, snoring, fatigue, nocturia, morning headaches, and excessive daytime sleepiness. SDB leads to increased risk of motor-vehicle crashes. Several studies have shown that sleep apnea is associated with hypertension, stroke, heart failure, obesity, metabolic syndrome, diabetes, neurocognitive deficits, gastroesophageal reflux disease, and erectile dysfunction. Such health problems can reduce the quality of life. Chiang et al. have found OSA prevalence to be 60.9% among adult primary care population who are at risk of OSA. Hence, due to these effects of OSA and its increasing prevalence, quick and accurate screening, diagnosis and treatment becomes very important.
Several studies have been done to evaluate the validity and usefulness of OPO in the screening of OSA. Hang et al. studied a total of 616 patients with nocturnal oximetry and PSG study and showed that OPO is a satisfactory diagnostic tool for patients with severe OSA.