Pulse oximetry in infants with Robin sequence

Infants with Robin sequence (RS) are at high risk for obstructive sleep apnea (OSA), but screening with poly(somno)graphy (P(S)G) is challenging. The aim of the study was to assess the relationships between different pulse oximetry (SpO₂) parameters and the mixed obstructive apnea-hypopnea index (MOAHI) in these infants. We also compared the findings to infants having other comorbidities (OSA-III). Different SpO₂ parameters were correlated with MOAHI in infants with RS and with OSA-III having similar OSA severity. The SpO₂ parameters were also compared between the 2 groups. Half of the infants with RS had nap studies. Mean MOAHI did not differ significantly between the 2 groups, and the proportion of infants with MOAHI > 10 events/h or ≥ 3% oxygen desaturation index (ODI 3%) > 10 events/h was also similar. Overall, the different SpO₂ parameters correlated better with MOAHI in infants with OSA-III than in those with RS. The best correlation was observed between ODI 3% and MOAHI in RS patients (r = 0.536, p < 0.001), and between the total hypoxic burden and MOAHI in OSA-III patients (r = 0.720, p < 0.0001). Mean ODI 3% was significantly lower in infants with RS (15.8 ± 22.3 (range 0.0-137.0) vs. 21.5 ± 18.3 (range 0.4-93.6) events/h for OSA-III, p = 0.024). Moreover, infants with OSA-III presented deeper desaturations and greater hypoxemic burdens.

SpO₂ parameters correlated better with MOAHI in infants with OSA-III compared to RS. These findings question the presence of a different OSA phenotype in infants with RS. Future studies should further investigate the potential role of the different SpO₂ parameters to screen for OSA in infants.

• Infants with Robin sequence (RS) are at high risk of obstructive sleep apnea (OSA). Polysomnography (PSG) is the gold standard for OSA diagnosis, but may be challenging due to its limited access, and the fact that it is time consuming and requires an experienced team. Pulse oximetry (SpO2) represents a simpler alternative and is used in some centers to screen for OSA. However, no pathological thresholds have been validated. Moreover, the oxygen desaturation index (ODI), which is commonly used, was found to correlate only moderately with the mixed and obstructive apnea-hypopnea index (MOAHI).

• We correlated different SpO2 parameters, such as the hypoxemic burden and the Δ12s index, to the MOAHI in infants with RS and compared the findings to infants with OSA associated to other comorbidities. It seems that infants with RS have a less severe OSA-related hypoxemic profile than infants with OSA-III. These findings question if different obstructive patterns exist according to the disorders.