Biology of the neonate
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Biology of the neonate · Jan 2005
Erythropoietin increases glutathione peroxidase enzyme activity and decreases lipid peroxidation levels in hypoxic-ischemic brain injury in neonatal rats.
We have previously shown that erythropoietin (Epo) exerts neuroprotective effects in the Rice-Vannucci model of neonatal hypoxic-ischemic brain injury. However, the mechanisms of Epo protection in this model are still unclear. ⋯ These results suggest that Epo exerts neuroprotective effects against hypoxic-ischemic brain injury at least partially via the modulation of antioxidant enzyme activity.
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Biology of the neonate · Jan 2004
Comparative StudyEvaluation of stroke volume via arterial pulse pressure waveforms in neonatal lambs.
Arterial pulse waveforms contain information about stroke volume (SV) as an integral of pulsatile flow. SV estimation is accurate in adults with proper pulse pressure measurement technique. It is unclear whether the same methods are suitable in critically ill infants in the neonatal clinical setting where the fidelity of pulse pressure measurements are uncertain. ⋯ The six SV estimates were then calibrated against flowmeter-derived SV and their accuracy and precision evaluated. Based on 6,479 waveforms, a systolic area method with pulse contour integration was the most accurate and precise. We conclude that neonatal pulse arterial waveforms embed SV information under a wide variety of hemodynamic and pressure waveform measurement conditions, and thus may be of potential clinical value in the assessment of newborn cardiovascular status.
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Biology of the neonate · Jan 2004
Review Historical ArticleOptimal oxygen saturation for preterm babies. Do we really know?
Oxygen is the most commonly used 'drug' in neonatal units as an integral part of respiratory support. It has also been known for half of the century that it is easy to damage the eyes of preterm infants by giving too much oxygen especially in the first few weeks of life. ⋯ A randomized controlled trial conducted more than 50 years ago first made clinicians aware of 'oxygen toxicity' in preterm infants, but no other controlled trial has ever been conducted since to clarify how much oxygen infants really need, or what oxygen saturation level is optimal in caring these preterm babies. Perhaps time has come for clinicians to resolve this 'uncertainty' by well-designed randomized trials.
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Biology of the neonate · Jan 2004
Translocation of coagulase-negative bacterial staphylococci in rats following intestinal ischemia-reperfusion injury.
Many patients with sepsis have bacteremia for which no septic focus is identified either clinically or by autopsy. This study was designed to determine the relationship between the ischemia-reperfusion injury (IRI) and bacterial translocation that might be involved in the pathogenesis of necrotizing enterocolitis. In the first experiment, a total of 32 Sprague-Dawley rats weighing 150-200 g were divided into four groups. ⋯ These isolates were not cytotoxic to MDCK cells and contained no delta toxin gene. Bacterial translocation of CoNS occurred following severe bowel ischemia and reperfusion injury. Intact mucosa integrity readily prevented bacterial translocation; however, bacterial translocation could occur in rats following mild IRI in the presence of a higher number of CoNS in the gut.
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Biology of the neonate · Jan 2003
ReviewResuscitation of premature infants: what are we doing wrong and can we do better?
Neonatal resuscitation is based on experience with little evidence to support the methods advocated. Current guidelines make no distinction between the techniques for term and very premature infants. The guidelines support the use of 100%, cold, dry oxygen delivered with devices that provide variable peak inspiratory pressures and tidal volumes with no positive end-expiratory pressure (PEEP). ⋯ It is surprising they are not routinely recommended for resuscitation when establishing the lung volume is paramount. Volutrauma is a potential problem in neonatal resuscitation and yet none of the devices give any indication of the tidal volume delivered. There is considerable potential for improvement in techniques of neonatal resuscitation through the application of evidence already available and much scope for further research in this field.