PP25 OVERNIGHT PULSE OXIMETRY AND CARDIORESPIRATORY POLYGRAPHY CORRELATION IN PAEDIATRIC OBSTRUCTIVE SLEEP APNOEA

Alicia Wan Ying Lim, Nur Afiqah Nubli, Yee Yen Tan

Department of Paediatrics, Hospital Tengku Ampuan Rahimah Klang, Selangor, Malaysia

Introduction
Overnight-pulse-oximetry (OPO) has become the standard screening tool for paediatric obstructive sleep apnoea (OSA) replacing full polysomnography (PSG). However, on occasions, the OPO is not sensitive enough to detect OSA of significant severity. Cardiorespiratory polygraphy (CRPG) is preferred as it is more sensitive in the diagnosis of OSA of significant severity compared to OPO, yet simpler to perform and to interpret compared to full PSG.

Objective
To compare the OSA severity derived from overnight oximetry and CRPG.  

Methodology
At our centre, all paediatric patients with suspected OSA undergo CRPG with concurrent OPO recording. We retrospectively reviewed the records these patients from 1/1/2025 to 20/6/2025. The overall OPO trend was reviewed and assigned a McGill-Oximetry-Score (MOS). The CRPG was manually scored according to AASM scoring criteria. The parameters from OPO and CRPG were extracted and analyzed.    

Results
Total patients was 23 with a median age of 8 years old (range 0.3-14). From OPO, the number of patients with MOS-1 was 12, MOS-2 was 5, MOS-3 was 3 and MOS-4 was 3. From the CRPG, the number of patients with no OSA was 2, mild OSA was 8, moderate OSA was 6, severe OSA was 2 and uninterpretable was 5. With MOS-1 or MOS-2 on OPO, the majority of OSA severity derived from CRPG fell in the category of normal or mild OSA (10 of 17), but there were also others (7 of 17) with moderate and severe in severity. On the other hand, with MOS-3 or MOS-4 on OPO, the correlation with OSA severity on CRPG was perfect. 

Conclusion
OPO and CRPG correlated well in moderate and severe OSA. However, a normal or mild severity of OSA on OPO (MOS-1 and MOS-2) does not correlate well with OSA severity derived from CRPG.