Intermittent hypoxia in preterm infants: Measurement using the desaturation index

Abstract

Objective The aims of this study were to: (i) Determine in preterm infants at neonatal discharge the prevalence of intermittent hypoxia (IH), as measured by the oxygen desaturation index (DSI) recorded by pulse oximetry and (ii) Determine the change in values for very preterm infants at 1‐month post discharge. Methods Preterm infants were recruited from the Wellington regional neonatal intensive care unit (NICU) and 24‐h pulse oximetry recordings performed immediately before discharge. Infants born <32 weeks gestational age (GA) had repeat oximetry 1‐month post discharge. Oxygenation measures included the 3% and 4% desaturation (DSI 3%, DSI 4%) indices. Results At discharge from the neonatal unit the median and interquartile range (IQR) for DSI 4% was 51 (31‐74) events per hour with normal mean SpO2 (median of 97.9% [97.2‐98.8 IQR]). Episodes of IH 1 month post discharge decreased with improvements of between 42% and 57% seen for the three DSI measures. Infants <32 weeks GA had higher median DSI 3 and 4% values at discharge but differences when compared with late preterm infants were not significant. Conclusions Preterm infants have frequent episodes of IH as measured by the 3% and 4% DSI when deemed otherwise ready for discharge home. Further research in a larger cohort of very preterm infants and also in term infants is needed to determine the significance of this finding.

Using continuous overnight pulse oximetry to guide home oxygen therapy in chronic neonatal lung disease

“…The prevalence and significance of intermittent hypoxemia on outcomes in preterm infants remains unclear but has been shown to be associated with poorer neurocognitive outcomes in older children with sleep disordered breathing . Previous studies have shown that the desaturation severity, or SpO 2 nadir, is likely to be significant but there is no consensus on what defines a severe desaturation (e.g.…”

“…Care should be taken when interpreting any study with excessive signal artefact and these studies should be repeated rather than making a management decision based on a suboptimal recording. A significant limitation is the inability to identify if clusters of desaturations are secondary to periodic breathing, central apnoeas or obstructive apnoeas . Paediatric respiratory specialists can apply their PSG experience through the visual analysis and pattern recognition of abnormal SpO 2 and heart rate waveforms to determine who may require more formal assessment by PSG.…”

“…32,[35][36][37] However, the American Academy of Sleep Medicine respiratory rules for children uses ODI 3% (even if SpO 2 nadir is >95%) and would score central apnoeas or hypopnoeas followed by a desaturation from SpO 2 100 to 95% on PSG. 38 The prevalence and significance of intermittent hypoxemia on outcomes in preterm infants remains unclear 39,40 but has been shown to be associated with poorer neurocognitive outcomes in older children with sleep disordered breathing. 41,42 Previous studies have shown that the desaturation severity, or SpO 2 nadir, is likely to be significant but there is no consensus on what defines a severe desaturation (e.g.…”

“…A significant limitation is the inability to identify if clusters of desaturations are secondary to periodic breathing, central apnoeas or obstructive apnoeas. 39,44 Paediatric respiratory specialists can apply their PSG experience through the visual analysis and pattern recognition of abnormal SpO 2 and heart rate waveforms to determine who may require more formal assessment by PSG.…”

Weaning oxygen in infants with bronchopulmonary dysplasia

“…Since publication of the ATS guidance [37] in 2018 the evidence base has expanded in relation to reference ranges for oxygen saturation parameters in healthy preterm and term infants [13,28,29,[46][47][48]. Using this data, we propose a structured weaning programme for infants with BPD at term equivalent age (TEA), receiving supplemental oxygen post-discharge from NICU.…”