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The risk for hyperoxaemia after apnoea, bradycardia and hypoxaemia in preterm infants
Insights
In preterm infants, high oxygen saturation (SpO₂) levels of 95% or more often occurred after interventions for apnoea, bradycardia, and cyanosis (ABC). These elevated SpO₂ levels persisted longer than the ABC events themselves.
Area of Science:
- Neonatal Medicine
- Pediatric Pulmonology
- Critical Care
Background:
- Preterm infants (<32 weeks gestation) supported with nasal continuous positive airway pressure (nCPAP) are susceptible to cardiorespiratory events.
- Apnoea, bradycardia, and cyanosis (ABC) episodes often necessitate increased oxygen support in this vulnerable population.
- Understanding post-intervention oxygen saturation dynamics is crucial for optimizing respiratory support in neonates.
Purpose of the Study:
- To determine the incidence and duration of achieving oxygen saturation (SpO₂) ≥95% following increased oxygen administration for ABC events in preterm infants.
- To examine the relationship between the duration of bradycardia and/or SpO₂ ≤80% and the subsequent achievement of SpO₂ ≥95%.
- To compare the duration of SpO₂ ≥95% under different pre-event oxygenation conditions.
Main Methods:
- Retrospective analysis of preterm infants (<32 weeks gestation) receiving nCPAP.
- Identification and detailed review of all ABC episodes requiring increased oxygen supply.
- Quantification of the duration and severity of bradycardia (<80 bpm), SpO₂ ≤80%, and SpO₂ ≥95% during and after ABC events.
Main Results:
- Oxygen saturation ≥95% was achieved in 79% of ABC episodes (202/257) where oxygen supply was increased.
- The duration of SpO₂ ≥95% was significantly longer (median 13 min) than the duration of bradycardia (median 1 min) or SpO₂ ≤80% (median 2 min) (p<0.001).
- Higher SpO₂ levels persisted longer when infants were on ambient air prior to the ABC event compared to those receiving oxygen before the event (p<0.01).
Conclusions:
- In preterm infants on nCPAP within the NICU, achieving SpO₂ ≥95% is common after increased oxygen for ABCs.
- The duration of elevated SpO₂ (≥95%) frequently exceeds the duration of the preceding bradycardia and/or SpO₂ ≤80%.
- These findings highlight the prolonged hyperoxemia potential following interventions for ABC events in preterm neonates.
Objective:
To investigate the occurrence and duration of oxygen saturation (SpO₂) ≥95%, after extra oxygen for apnoea, bradycardia, cyanosis (ABC), and the relation with the duration of bradycardia and/or SpO₂ ≤80%.
Methods:
All preterm infants <32 weeks' gestation supported with nasal continuous positive airway pressure (nCPAP) admitted to our centre were eligible for the study. We retrospectively identified all episodes of ABCs. In ABCs where oxygen supply was increased, duration and severity of bradycardia (<80 bpm), SpO₂ ≤80%, SpO₂ ≥95% and their correlation were investigated.
Results:
In 56 infants, 257 ABCs occurred where oxygen supply was increased. SpO₂ ≥95% occurred after 79% (202/257) of the ABCs, duration of extra oxygen supply was longer in ABCs with SpO₂ ≥95% than without SpO₂ ≥95% (median (IQR) 20 (8-80) vs 2 (2-3) min; p<0.001)). The duration of SpO₂ ≥95% was longer than bradycardia and SpO₂ ≤80% (median (IQR) 13 (4-30) vs 1 (1-1) vs 2 (1-2) min; p<0.001). SpO₂ ≥95% lasted longer when infants were in ambient air than when oxygen was given before the ABC occurred (median (IQR)15 (5-38) min vs 6 (3-24) min; p<0.01).
Conclusions:
In preterm infants supported with nCPAP in the neonatal intensive care unit (NICU), SpO₂ ≥95% frequently occurred when oxygen was increased for ABCs and lasted longer than the bradycardia and SpO₂ ≤80%.
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