105 Non-Invasive Measurements of Hemodynamic Transition at Birth

Abstract

Abstractsvitamin-E levels were significantly increased in SMOFlipid group. Oleic and Linoleic acid levels were increased in both groups. No significant differences were noted in post study Docosahexaenoic acid (DHA) levels in both groups despite higher levels of DHA in SMOFlipid. Conclusions SMOFlipid was safe, well tolerated and also showed beneficial effect in terms of reduction of oxidative stress by reducing lipid peroxidation levels in high risk preterm neonates. Vascular pressure reactivity is the ability of vascular smooth muscle to respond to changes in transmural pressure. In the cerebral circulation this reactivity -or autoregulation -limits cerebral blood flow variation over a range of cerebral perfusion pressures ensuring adequate perfusion and oxygenation to the brain. CEREBRAL AUTOREGULATION IN THE NEWBORNIn adults cerebrovascular pressure reactivity can be determined by observing the response of intracranial pressure (ICP) to changes in mean arterial blood pressure. Non-invasive techniques such as transcranial Doppler ultrasound and near-infrared spectroscopy have been validated against ICP measurements, which have enabled continuous assessment of cerebral autoregulation to be investigated in newborn infants.A number of different techniques have been described, including static and dynamic measurements and analysis in the time and frequency domain, yet despite many years of research the characteristics of cerebral autoregulation in the newborn are still not clear.Both the presence and limits of autoregulation has been much debated although there is increasing evidence that autoregulation, while present in healthy infants, is impaired in sick term and preterm neonates and that this impairment may be a predictor of poor outcome.In clinical practice there is a reliance on blood pressure measurements alone to make informed clinical decisions, which ignores the complex circulatory control mechanisms that exist to optimize oxygen delivery to the brain. The ability to obtain continuous quantitative information on cerebral autoregulation at the cotsie would represent a significant advance in the management of these patients. Objective To investigate the hemodynamic changes during transition at birth obtaining non-invasive physiological data in healthy term infants. Methods In 18 newborns (GA 39 weeks (38-39)) born by a caesarian section; arterial oxygen saturation (SaO 2 ) (preductally), heart rate (HR) and non-invasive blood pressure (BP) were measured and echocardiography using M-mode and Doppler flow was performed at 2, 5 and 10 minutes after birth. Results Oxygen saturation and HR were within recommended target ranges. Mean BP did not change between measurement intervals (55 mm Hg at 2 min, 54 mm Hg at 5 min. and 54 mm Hg at 10 min) and was similar as BP measured at day 1. Objective To evaluate the effect of slow versus rapid rates of advancement of enteral feed volumes upon the clinical outcomes in preterm infants with 750-1250g birth weight. Study Design A total of 92 stable neonates with the birth ...

Non-invasive measurements of ductus arteriosus flow directly after birth

“…Infants were included after completing enrolment for a previous study that focused on changes in left ventricular dimensions and function directly after birth 18. Parents were approached during preoperation visit or by telephone at least one day before the caesarean section took place.…”

“…Standard two-dimensional (2D) grey-scale images were acquired from the suprasternal, parasternal and apical views and stored in digital format 18. To assess the velocity time integral (VTI), Doppler pulsed wave measurements were obtained in the apical ‘five-chamber’ parasternal long-axis view at the level of the aortic annulus for left ventricular output (LVO) and in the parasternal short-axis view at the level of the pulmonary annulus for RVO.…”

“…To assess the velocity time integral (VTI), Doppler pulsed wave measurements were obtained in the apical ‘five-chamber’ parasternal long-axis view at the level of the aortic annulus for left ventricular output (LVO) and in the parasternal short-axis view at the level of the pulmonary annulus for RVO. Aortic diameter was measured at the level of the aortic annulus in the parasternal long axis, pulmonary diameter was measured at the level of the pulmonary annulus in the parasternal short axis and diameter of the aortic and pulmonary annulus were measured at each time point 18. The DA was visualised in its long axis from the pulmonary artery and the descending aorta in the suprasternal view.…”