Study objectives: 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.
Methods: 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.
Results: 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.
Conclusions: 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.
Keywords: CPAP; PAP initiation; evaluation; obstructive sleep apnea; oximetry.
© 2018 American Academy of Sleep Medicine.