Hypoxemia and Risk for Bronchopulmonary Dysplasia In Preterm Infants

Bronchopulmonary dysplasia (BPD) is a chronic lung disease in infants associated with extreme prematurity.  Understanding contributing factors is important since there is a strong link between this condition and neurodevelopmental impairment and other childhood disease.  This study demonstrated a strong association between frequency and severity of oxygen desaturations in the development of severe BPD.  Importantly, oxygen desaturations of 1 minute or longer were significantly correlated.  

Abstract

Rationale: Bronchopulmonary dysplasia increases the risk of disability in extremely preterm infants. Although the pathophysiology remains uncertain, prior exposure to intermittent hypoxemia may play a role in this relationship. Objectives: To determine the association between prolonged episodes of intermittent hypoxemia and severe bronchopulmonary dysplasia. Methods: A post hoc analysis of extremely preterm infants in the Canadian Oxygen Trial who survived to 36 weeks' postmenstrual age was performed. Oxygen saturations <80% for ⩾1 minute and the proportion of time per day with hypoxemia were quantified using continuous pulse oximetry data that had been sampled every 10 seconds from within 24 hours of birth until 36 weeks' postmenstrual age. The study outcome was severe bronchopulmonary dysplasia as defined in the 2001 NIH Workshop Summary. Measurements and Main Results: Of 1,018 infants, 332 (32.6%) developed severe bronchopulmonary dysplasia. The median number of hypoxemic episodes ranged from 0.8/day (interquartile range, 0.2-1.1) to 60.2/day (interquartile range, 51.4-70.3) among the least and most affected 10% of infants. Compared with the lowest decile of exposure to hypoxemic episodes, the adjusted relative risk of severe bronchopulmonary dysplasia increased progressively from 1.72 (95% confidence interval, 1.55-1.90) at the 2nd decile to 20.40 (95% confidence interval, 12.88-32.32) at the 10th decile. Similar risk gradients were observed for time in hypoxemia. Significant differences in the rates of hypoxemia between infants with and without severe bronchopulmonary dysplasia emerged within the first week after birth. Conclusions: Prolonged intermittent hypoxemia beginning in the first week after birth was associated with an increased risk of developing severe bronchopulmonary dysplasia among extremely preterm infants. Clinical trial registered with www.isrctn.com (ISRCTN62491227) and www.clinicaltrials.gov 

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Setting Discharge Goals for High Risk Infants

 A useful and much study needed since neonatologists and consulting pediatric pulmonologists rely on few reliable indicators to judge discharge readiness.  And with little guidance, often managed care restrictions may prompt premature discharge.  A baseline CO2 retention above a certain threshold always seemed like at least 1 useful measure, now supported by this South Korean study.

Children with chronic lung disease of prematurity tend to have reduced lung function, increased susceptibility to respiratory viral illness, and elevated risk for rehospitalization.  Setting goals for discharge are greatly needed in this high risk population.

Capillary partial pressure of carbon dioxide for predicting rehospitalization in preterm infants under noninvasive respiratory support with severe bronchopulmonary dysplasia

Abstract

Background

The severity of bronchopulmonary dysplasia (BPD) is an important predictor of prognosis in preterm infants. However, the severity of BPD was determined mainly by the degree of oxygen supplementation and mode of respiratory support.

Objectives

This retrospective study aimed to examine the role of partial pressure of carbon dioxide (pCO2) in predicting rehospitalization among preterm infants with severe BPD without invasive ventilation at 36 weeks' postmenstrual age (PMA).

Methods

We assessed preterm infants aged <32 gestational weeks with severe BPD who were receiving noninvasive respiratory support at 36 weeks' PMA. Patients were compared after stratifying them according to the history of rehospitalization owing to respiratory infection before a corrected age (CA) of 1 year and pCO2 measured by capillary blood gas analysis at 36 weeks' PMA.

Results

Among 54 infants who had severe BPD with noninvasive respiratory support at 36 weeks' PMA, 16 (29.6%) experienced rehospitalization due to respiratory problems. At 36 weeks' PMA, the amount of oxygen supplementation (0.30 vs. 0.28, p = 0.021) and pCO2 (62.1 vs. 53.6 mmHg, p = 0.006) were higher in the rehospitalization group than in the no rehospitalization group. Multivariate logistic analysis findings indicated that pCO2 ≥ 57.4 mmHg was the only factor associated with rehospitalization (adjusted odds ratio: 8.017, 95% confidence interval 1.239–51.859).

Conclusion

High pCO2 during noninvasive respiratory support at 36 weeks' PMA in severe BPD was associated with rehospitalization. Consideration of the degree of impairment in ventilatory capacity may improve the prediction of later respiratory outcomes in infants with BPD.

Pediatric Pulmonology

Volume56, Issue12

December 2021

Pages 3863-3869

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