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Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin
Published on: August 25, 2022
Association of Day-1 Hemoglobin Oxygen Affinity (p50) with Severe Intraventricular Hemorrhage in Preterm Infants
1Department of Pediatrics, Bağcılar Training and Research Hospital, University of Health Sciences, Istanbul, Turkey.
Insights
A lower partial pressure of oxygen at 50% hemoglobin saturation (p50) in preterm infants is linked to a higher risk of severe intraventricular hemorrhage (IVH). This finding highlights p50 as a potential predictor for IVH in neonates.
Area of Science:
- Neonatalogy
- Pediatric Neurology
- Critical Care Medicine
Background:
- The partial pressure of oxygen at which hemoglobin is saturated at 50% (p50) is a key indicator of oxygen loading and tissue unloading.
- Intraventricular hemorrhage (IVH) is a significant concern in preterm infants, often leading to severe neurological complications.
Purpose of the Study:
- To investigate the association between lower p50 values and the incidence of severe IVH (grades III-IV) in very preterm infants.
- To determine if p50 can serve as a predictive marker for severe IVH in this vulnerable population.
Main Methods:
- Retrospective cohort study of very preterm infants (gestational age ≤ 32 weeks) admitted between January 2020 and December 2023.
- p50 was measured from the first arterial blood gas within 12 hours of birth.
- Severe IVH was diagnosed via cranial ultrasonography, and multivariable logistic regression was used for analysis, adjusting for gestational age, sex, sepsis, and ventilation.
Main Results:
- Out of 290 infants, 12% experienced severe IVH.
- A significant decrease in median day-1 p50 was observed with increasing IVH severity (21.5 mmHg for no IVH, 18.7 mmHg for mild IVH, 16.0 mmHg for severe IVH; P < 0.001).
- Lower day-1 p50 was independently associated with severe IVH (adjusted odds ratio 1.38 per 1 mmHg decrease; P = 0.012).
Conclusions:
- Lower day-1 p50 is independently associated with a higher incidence of severe IVH in very preterm infants.
- p50 may be a valuable biomarker for predicting the risk of severe IVH in neonates.
Objective:
The partial pressure of oxygen at which hemoglobin is saturated at 50% (p50) reflects the balance between oxygen loading and tissue unloading. This study was conducted to ascertain if a lower p50 is linked to a greater incidence of severe intraventricular hemorrhage (IVH) in preterm infants.
Methods:
This retrospective cohort study included very preterm infants (≤ 32 weeks' gestation) admitted to the neonatal intensive care unit between January 1, 2020 and December 31, 2023. p50 was obtained from the first arterial blood gas, measured within 12h after birth. IVH was graded using cranial ultrasonography according to the Papile classification; severe IVH was defined as grades III-IV. Multivariable logistic regression models adjusted for gestational age, sex, early-onset sepsis, and invasive ventilation exposure were used to ascertain role of hemoglobin p50 for predicting severe IVH in very preterm infants.
Results:
Out of 290 eligible infants [mean (SD) gestational age: 28.4 (2.6) weeks; mean (SD) birth weight: 1210 (365 g], 230 (79%) had no IVH, 26 (9%) had mild IVH, and 34 (12%) had severe IVH. The median day-1 p50 decreased with increasing IVH severity (no IVH: 21.5 mmHg; mild IVH: 18.7 mmHg; severe IVH: 16.0 mmHg; P < 0.001). In adjusted models, lower day-1 p50 was independently associated with severe IVH (adjusted odds ratio 1.38 per 1 mmHg decrease; 95%CI 1.09-1.82; P = 0.012).
Conclusions:
Lower day-1 p50 is independently associated with severe IVH in very preterm infants.
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