Postnatal Steroids Effects on Cardiac Function in Extremely Preterm

"Surveillance of Postnatal Steroids Effects on Cardiac Function in Extremely Preterm Infants With Evolving BPD: the SPEC Study."

Hypothesis/Study question

In infants born at less than 29 weeks of estimated gestational age, what are the effects of dexamethasone use on cardiac structure/performance and lung water content?

Study objectives

To measure effects before and after dexamethasone administration on cardiac structure/performance will be evaluated by using the M-mode technique (Devereux method (25-27) and lung water content will be specifically determined by the degree of water retention in premature lungs assessed by lung ultrasound at the pre specified time points.

Methodology / Study design

Single center, prospective observational cohort study planning to enroll eligible patients over a period of 12 months

This study investigates the effects of dexamethasone on cardiac structure/performance and lung water content in the extremely preterm population undergoing treatment for significant lung disease. For that, the specific aims are to determine the occurrence, evolution over time and possible hemodynamic impact of left ventricular hypertrophy and occurrence and degree of water retention in premature lungs, after dexamethasone administration. As secondary outcomes, this study also investigates the effects of dexamethasone on the ductus arteriosus, body growth, and autonomic regulation heart rate variability, as well as other important outcomes outlined in this protocol.

This study hypothesize that in some infants dexamethasone will be associated with the occurrence of early and/or prolonged left ventricular hypertrophy, which may be associated with changes in cardiac performance. It also hypothesize that the anti-inflammatory effects of dexamethasone would improve inflammation of immature lungs, leading to a decrease in interstitial fluid.

Inclusion Criteria:

• < 29 weeks of gestational age at birth admitted at the McGill University Children Hospital's neonatal intensive care unit
• To be initiated on dexamethasone therapy for treatment of significant lung disease as per medical team decision.

Exclusion Criteria:

• Congenital heart disease (except: Atrial septum defect (ASD), Ventricular septum defect (VSD)
• Major congenital anomalies/genetic disorder (Trisomy 13, 18, 21)
• Congenital severe lung or airway malformation (Trachea-esophageal fistula, congenital pulmonary airway malformation, congenital diaphragmatic hernia)
• Twin-twin transfusion syndrome