Bradycardias are associated with more severe effects on cerebral oxygenation in very preterm infants than in late preterm infants

Early Human Development
Lisa M WalterFlora Y Wong

Abstract

Commonly the magnitude and frequency of bradycardia is underestimated in the neonatal unit due to the long averaging time used in bedside oximeters. We aimed to assess the frequency and severity of bradycardia in preterm infants using the lowest averaging time (2 s) available on a clinical oximeter, compared with bradycardia detected using electrocardiogram (ECG), and whether bradycardia severity and postmenstrual age affected cerebral oxygenation. Preterm infants (10 M/9F) were studied longitudinally at 26-31 (very preterm) and 32-38 weeks (late preterm) postmenstrual age. Heart rate falls calculated from ECG were used to determine mild or moderate/severe (MS) bradycardias. Cerebral tissue oxygenation index (TOI, %) was recorded and fractional tissue oxygen extraction (FTOE) calculated. Of the 615 bradycardias scored using ECG criteria, 10% were not detected by oximetry. TOI falls associated with bradycardias were greater for MS bradycardias compared with Mild for both groups (p < 0.001 for both). The FTOE associated with MS bradycardias was higher for the very preterm compared with the late preterm group (p < 0.001). In very preterm infants 61% of MS and 35% Mild bradycardias were associated with TOI nadirs below 55%. Even th...Continue Reading

Related Concepts

Related Feeds

Bradyarrhythmias

Bradyarrhythmias are slow heart rates. Symptoms may include syncope, dizziness, fatigure, shortness of breath, and chest pains. Find the latest research on bradyarrhythmias here.

© 2022 Meta ULC. All rights reserved