No consensus exists regarding monitoring the initiation of positive airway pressure (PAP) by oximetry. A PAP device report may be insufficient to ensure a good therapeutic response in all patients. This study aimed to identify patients who would potentially benefit from oximetry monitoring during PAP initiation.
PAP initiation was routinely monitored at home with an oximeter. Data were reviewed for all patients who underwent PAP initiation in 2015, including a baseline sleep study and PAP initiation data. Group A included patients with an apnea-hypopnea index as determined from the PAP device (AHIPAP) of < 5 events/h and a residual 3% oxygen desaturation index (ODI3) of ≥ 10 events/h. Group B included all remaining patients. Cases with a leak of over 24 L/min or with an oximetry recording time of < 1 hour were excluded. AHIPAP < 5 events/h and residual ODI3 < 10 events/h represented good PAP responses.
From 787 patients, 723 were included in this study. Among these, 158 had an AHIPAP of ≥ 5 events/h, whereas 565 had an AHIPAP of < 5 events/h. Group A consisted of 129 patients (18%). The sensitivity of the PAP device indicating a good PAP response reached 93.1%, with a specificity of 37.2%, a negative predictive value of 96.2%, and a positive predictive value of 23.9% using body mass index (BMI) ≥ 30 kg/m2 and baseline SpO2 < 92% as the cutoff points.
Relying only on the PAP device parameter to evaluate therapeutic responses provided inconsistent results in one-fifth of cases. Thus, oximetry monitoring during PAP initiation is recommended when baseline SpO2 < 92% or when BMI ≥ 30 kg/m2. Otherwise, oximetry monitoring remains optional.
Koivumäki V, Maasilta P, Bachour A. Oximetry monitoring recommended during pap initiation for sleep apnea in patients with obesity or nocturnal hypoxemia. J Clin Sleep Med. 2018;14(11):1859–1863.