A pilot study on the biochemical effects of repeated administration of 24% oral sucrose vs. 30% oral dextrose on urinary markers of adenosine triphosphate degradation.

Objectives: Premature neonates often receive oral sucrose or dextrose before tissue-damaging procedures (TDPs). Previous work showed that a single dose of sucrose, but not dextrose, increased cellular energy utilization and ATP degradation. This pilot study probes the effects of repeated administration of sucrose or dextrose on energy metabolism.

Oral dextrose reduced procedural pain without altering cellular ATP metabolism in preterm neonates: a prospective randomized trial.

Objective: To examine the effects of 30% oral dextrose on biochemical markers of pain, adenosine triphosphate (ATP) degradation, and oxidative stress in preterm neonates experiencing a clinically required heel lance.

Study Design: Utilizing a prospective study design, preterm neonates that met study criteria (n = 169) were randomized to receive either (1) 30% oral dextrose, (2) facilitated tucking, or (3) 30% oral dextrose and facilitated tucking 2 min before heel lance. Plasma markers of ATP degradation (hypoxanthine, uric acid) and oxidative stress (allantoin) were measured before and after the heel lance.

Oxidative Stress Biomarker Decreased in Preterm Neonates Treated With Kangaroo Mother Care.

Objective: Due to physiological and metabolic immaturity, prematurely born infants are at increased risk because of maternal separation in many neonatal intensive care units (NICUs). The stress induced from maternal-infant separation can lead to well-documented short-term physiologic instability and potentially lifelong neurological, sociological, or psychological sequelae. Based on previous studies of kangaroo mother care (KMC) that demonstrated improvement in physiologic parameters, we examined the impact of KMC on physiologic measures of stress (abdominal temperature, heart rate, oxygen saturation, perfusion index, near-infrared spectrometry), oxidative stress, and energy utilization/conservation in preterm infants.

Differential effects of the retinopathy of prematurity exam on the physiology of premature infants.

Objective: To compare the differential effects of the retinopathy of prematurity (ROP) examination on the physiology of premature infants with and without oxygen support.

Study Design: We collected data from 42 premature infants (room air = 19, oxygen support = 23) and compared physiological metrics including heart rate (HR), systemic peripheral saturation (SpO), mesenteric tissue oxygen saturation (StO) and clinical events (oxygen desaturation episodes, bradycardia events, and gastric residuals).

Results: We found significant differences between groups in HR during and briefly after the exam, and in mesenteric StO during eye drop administration, eye exam, and up to 8 min after the exam.

Platelet-Neutrophil Interactions Are Lower in Cord Blood of Premature Newborns.

Objective: To quantify platelet-neutrophil interaction by flow cytometry, in newborn cord blood, as a function of gestational age.

Rationale: Little is known about platelet function markers in the newborn, and developmental variations in these markers are not well described.

Methods: Cord blood samples were obtained from 64 newborns between 23 and 40 weeks' gestation.

The Energy Costs of Prematurity and the Neonatal Intensive Care Unit (NICU) Experience.

Premature neonates are in an energy deficient state due to (1) oxygen desaturation and hypoxia events, (2) painful and stressful stimuli, (3) illness, and (4) neurodevelopmental energy requirements. Failure to correct energy deficiency in premature infants may lead to adverse effects such as neurodevelopmental delay and negative long-term metabolic and cardiovascular outcomes. The effects of energy dysregulation and the challenges that clinicians in the Neonatal Intensive Care Unit (NICU) face in meeting the premature infant's metabolic demands are discussed.

The relationship of red blood cell transfusion to intestinal mucosal injury in premature infants.

Objective: To determine the incidence of intestinal mucosal injury before and after transfusions in premature infants.

Study Design: Urine was collected throughout the hospital stay of 62 premature infants and specimens obtained within 24h before and after transfusion were assayed for intestinal fatty acid binding protein (iFABP). A urinary iFABP:creatinine ratio (iFABP:Cr) of 2.

Oral sucrose for heel lance enhances adenosine triphosphate use in preterm neonates with respiratory distress.

Objective: To examine the effects of oral sucrose on procedural pain, and on biochemical markers of adenosine triphosphate utilization and oxidative stress in preterm neonates with mild to moderate respiratory distress.

Study Design: Preterm neonates with a clinically required heel lance that met study criteria (n = 49) were randomized into three groups: (1) control (n = 24), (2) heel lance treated with placebo and non-nutritive sucking (n = 15) and (3) heel lance treated with sucrose and non-nutritive sucking (n = 10). Plasma markers of adenosine triphosphate degradation (hypoxanthine, xanthine and uric acid) and oxidative stress (allantoin) were measured before and after the heel lance.

Urinary Hypoxanthine as a Measure of Increased ATP Utilization in Late Preterm Infants.

Objective: To examine the effect of neonatal morbidity on ATP breakdown in late preterm infants.

Study Design: Urinary hypoxanthine concentration, a marker of ATP breakdown, was measured from 82 late preterm infants on days of life (DOL) 3 to 6 using high-performance liquid chromatography. Infants were grouped according to the following diagnoses: poor nippling alone (n = 8), poor nippling plus hyperbilirubinemia (n = 21), poor nippling plus early respiratory disease (n = 26), and respiratory disease alone (n = 27).

Urinary Allantoin Is Elevated in Severe Intraventricular Hemorrhage in the Preterm Newborn.

Germinal matrix intraventricular hemorrhage (IVH) is the most common type of intracranial hemorrhage observed in preterm neonates. It is a precursor of poor neurocognitive development, cerebral palsy, and death. The pathophysiology is not well defined, but damage to the fragile germinal matrix vasculature may be due to free radicals generated during inflammation and as a consequence of ischemia followed by reperfusion.

Oral sucrose for heel lance increases adenosine triphosphate use and oxidative stress in preterm neonates.

Objective: To examine the effects of sucrose on pain and biochemical markers of adenosine triphosphate (ATP) degradation and oxidative stress in preterm neonates experiencing a clinically required heel lance.

Study Design: Preterm neonates that met study criteria (n = 131) were randomized into 3 groups: (1) control; (2) heel lance treated with placebo and non-nutritive sucking; and (3) heel lance treated with sucrose and non-nutritive sucking. Plasma markers of ATP degradation (hypoxanthine, xanthine, and uric acid) and oxidative stress (allantoin) were measured before and after the heel lance.

Procedural pain and oxidative stress in premature neonates.

Unlabelled: Preterm neonates exposed to painful procedures in the neonatal intensive care unit exhibit increased pain scores and alterations in oxygenation and heart rate. It is unclear whether these physiological responses increase the risk of oxidative stress. Using a prospective study design, we examined the relationship between a tissue-damaging procedure (TDP; tape removal during discontinuation of an indwelling central arterial or venous catheter) and oxidative stress in 80 preterm neonates.

Biochemical measurement of neonatal hypoxia.

Neonatal hypoxia ischemia is characterized by inadequate blood perfusion of a tissue or a systemic lack of oxygen. This condition is thought to cause/exacerbate well documented neonatal disorders including neurological impairment. Decreased adenosine triphosphate production occurs due to a lack of oxidative phosphorylation.

The role of morphine in a rat model of hypoxic-ischemic injury.

We investigated whether morphine plays a neuroprotective role in a neonatal rat pup model of bilateral carotid artery occlusion with hypoxia. At postnatal day 10, rats received either morphine (n = 7), naloxone (n = 7), or saline placebo (n = 15) after hypoxic-ischemic injury. Survival (days), weight gain and animal testing (negative geotaxis, surface righting, and rotarod) were compared between treatment groups.

An animal model for measuring the effect of common NICU procedures on ATP metabolism.

Neonates exposed to common neonatal intensive care unit (NICU) procedures show alterations in heart rate, blood pressure, and oxygen saturation. However, it is unclear if these physiologic changes increase adenosine triphosphate (ATP) utilization, thus potentially increasing the risk for tissue hypoxia in medically fragile neonates. Plasma uric acid is a commonly used marker of increased ATP utilization because uric acid levels increase when ATP consumption is enhanced.

Necrotizing enterocolitis is associated with neonatal intestinal injury.

Purpose: We hypothesized that a subset of premature newborns has subclinical, intestinal mucosal compromise that predisposes to the development of necrotizing enterocolitis (NEC) days or weeks later.

Methods: Fifty-five newborns of 23 to 36 weeks' gestational age were identified, and urine was collected over the first 90 hours of life. The urinary concentration of intestinal fatty acid binding protein (iFABP(u)), a sensitive marker for intestinal injury, was determined.

Relationship between opioid therapy, tissue-damaging procedures, and brain metabolites as measured by proton MRS in asphyxiated term neonates.

To examine the effects of opioid and tissue-damaging procedures (TDPs) [i.e. procedures performed in the neonatal intensive care unit (NICU) known to result in pain, stress, and tissue damage] on brain metabolites, we reviewed the medical records of 28 asphyxiated term neonates (eight opioid-treated, 20 non-opioid treated) who had undergone magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (MRS) within the first month of life as well as eight newborns with no clinical findings of asphyxial injury.

Effect of dopamine on vascular reactivity in near-term lamb carotids: role of the endothelium.

Many neonates are diagnosed with hypotension in the first 24 hr of life. Those with severe hypotension are often given high doses of dopamine at 10 to 20 microg/kg/min. This study examined the hypothesis that dopamine, a vasoactive drug commonly used in the neonatal intensive care unit, alters vascular reactivity.

Dexamethasone alters vascular reactivity by enhancing COX-related vasodilatation in fetal ovine carotids.

Based on preliminary studies that contractile efficacy was altered in vertebral and basilar arteries from neonatal donors treated with postnatal glucocorticoids, we examined the hypothesis that postnatal dexamethasone (DEX), a glucocorticoid used for respiratory disease in neonates, can alter vascular reactivity. Using near-term fetal lamb carotids, we measured 5-hydroxytryptamine (5-HT) dose-response relationship in DEX-treated and untreated arteries. We found that DEX incubation for 1 h had no effect on 5-HT sensitivity and agonist affinity but significantly reduced 5-HT contractile efficacy, a response that became even more pronounced after 4 h of DEX treatment.

Use of opioids in asphyxiated term neonates: effects on neuroimaging and clinical outcome.

Perinatal asphyxia is a common cause of neurologic morbidity in neonates who are born at term. Asphyxiated neonates are frequently treated with analgesic medications, including opioids, for pain and discomfort associated with their care. On the basis of previous laboratory studies suggesting that opioids may have neuroprotective effects, we conducted a retrospective review of medical records of 52 neonates who were admitted to our neonatal intensive care unit between 1995 and 2002 and had undergone magnetic resonance imaging (MRI) of the brain.