Background: As per the AASM Manual for the Scoring of Sleep and Associated Events (2020), RIPSum can be used as a flow surrogate to score respiratory events in the absence of oronasal thermistor or pressure transducer signals. There is no specific data to evaluate impact of flow signal used in paediatrics.
Aims: To compare nasal flow and RIPSum for detection of respiratory events during cardiorespiratory polygraphy (CRP) in children
Method: Paediatric CRP studies with study time > 5 hours and adequate flow and RIPSum signals were retrospectively selected. Studies were duplicated, removing all previous analysis and video. A physiologist analysed the data using each flow source separately.
Results: Fifty four studies were selected. Data was subject to Wilcoxon test for difference (Table 1). Seven studies differed by one severity category; one study differed by two severity categories. One study differed between a positive and negative conclusion.
Table 1 ?Apnoea Hypopnea Index (AHI), Obstructive Apneoa Index (OAI), Obstructive Hypopnea Index (OHI) and Central Apnoea Index (CAI) when scored using nasal flow or RIPSum.
|
Nasal flow (Median, IQR) |
RIPSum (Median, IQR) |
p | R | |
| AHI | 1.3, 0.2-4.9 | 0.9, 0.2-3.30 | <0.001 | -4.785 |
| OAI | 0.2, 0-1.3 | 0, 0-0.3 | <0.001 | -4.484 |
| OHI | 0.4, 0-3.2 | 0.5, 0-3.10 | 0.702 | -0.383 |
| CAI | 0, 0-0.2 | 0, 0-0.2 | 0.391 | -2.06 |
Conclusion: There was a significant difference in AHI and OAI between RIPSum and nasal flow. On average, AHI scored using nasal flow was higher; use of RIPSum without nasal flow can underestimate AHI. However, impact on overall clinical outcome is limited.