Blunted sympathoadrenal activation accompanies hemodynamic stability after early ventilation and delayed cord clamping at birth in preterm lambs
Joseph J Smolich, Kelly R Kenna, Jonathan P Mynard, Sarah E Phillips, Gavin W Lambert
Pediatric Research | NATURE PUBLISHING GROUP | Published : 2019
BACKGROUND: As surges in circulating norepinephrine and epinephrine have chronotropic, pressor, and inotropic effects, we tested the hypothesis that blunted rises in these catecholamines during preterm birth accompanied hemodynamic stability observed after early ventilation and delayed cord clamping (DCC), with findings compared to immediate cord clamping (ICC) and a non-asphyxial cord clamp-to-ventilation interval. METHODS: Anesthetized preterm fetal lambs were instrumented with arterial micromanometers to obtain pressure and the maximal rate of pressure rise (dP/dtmax) as a surrogate of ventricular contractility and an aortic catheter to obtain blood samples for catecholamine assay. Fetuse..View full abstract
Awarded by National Health and Medical Research Council of Australia (NHMRC)
We thank Magdy Sourial, Amy Tilley, Sara White, Aaron Mocciaro, Rebecca Sutton, Dr. Nikita Gupta, and Dr. Ramona Krauss for technical assistance with experimental studies. This work was supported by Project Grant 1105137 from the National Health and Medical Research Council of Australia (NHMRC) and the Victorian Government's Operational Infrastructure Support Program. J.P.M. was supported by a co-funded NHMRC Career Development Fellowship and National Heart Foundation Future Leader Fellowship and G.W.L. by an NHMRC Research Fellowship.