Neonatology
Patrick McNamara, MB, BCH, BAO, DCH, MSc (Paeds), MRCP, MRCPCH, FASE (he/him/his)
Professor of Pediatrics-Neonatology
Pediatrics
University of Iowa Stead Family Department of Pediatrics
Iowa City, Iowa, United States
The postnatal transition is characterized by major changes in cardiac loading conditions and shunt flow patterns placing the newly born at increased risk. In addition, autonomic dysregulation and neuro-behavioral immaturity increase the vulnerability of the most immature patients to interventions or care-practices common in the NICU. Yet, in considering the biologic nature of hemodynamic disturbance a potential relationship to ‘non-cardiovascular’ interventions is oftentimes overlooked. Amongst “routine care” interventions, the impact of mechanical ventilation, surfactant, caffeine and kangaroo mother care on hemodynamic stability remains poorly investigated.
While achieving adequate distending pressure is necessary for optimal alveolar recruitment, the impact of altered preload/afterload on heart function is a major determinant of hemodynamic stability. Of concern, changes in heart rate or arterial pressure may be late and provide little diagnostic insight. Exposure to high tidal volumes or pressures during delivery room resuscitation or failure to wean distending pressure settings in response to rapidly improving lung compliance after surfactant treatment, may compromise pulmonary and systemic blood flow. In addition, changes in transductal pressure gradient after surfactant treatment may lead to major changes in flow across the patent ductus arteriosus. These alterations in pre-ductal cardiac output leading to cerebral ischemia-reperfusion may contribute to the pathogenesis of preterm brain injury. On the contrary several RCTs have demonstrated physiological hemodynamic benefits of Kangaroo care including enhanced cerebral blood flow and cardiac function. We review evidence regarding the hemodynamic impact of ‘non-cardiovascular’ practices, identify relevant knowledge gaps and research priorities and discuss the role of targeted neonatal echocardiography.
Speaker: Patrick J. McNamara, MB BCH BAO MSC – University of Iowa Roy J. and Lucille A. Carver College of Medicine
Speaker: Satyan Lakshminrusimha, MD – University of California Davis Children's Hospital
Speaker: J Lauren Ruoss, MD – University of Florida College of Medicine
Speaker: Amy Stanford, MD – University of Iowa Stead Family Children's Hospital
Speaker: Arvind Sehgal, PhD – Monash Children’s Hospital