Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “preterm neonates”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

Lymphocyte phenotypes and infection incidence in transfused preterm neonates.

The immunomodulating effects of repeated exposure to blood from multiple donors coupled with an immature immune system may predispose the preterm neonate to an increased incidence of infection in his first few months of life. To test this hypothesis, we compared lymphocyte phenotypes, serum IgG concentrations, and histories of infection and rehospitalization in neonates at 4 months corrected age. Two of the study groups were preterm infants who had been transfused with either frozen, deglycerolized or CMV-negative, gamma-irradiated blood. Control groups consisted of nontransfused term and preterm infants. There were no differences found in lymphocyte phenotypes or serum IgG concentrations of controls or transfused infants. No differences were found in the infection or rehospitalization incidence in the transfused infants as compared with nontransfused preterm neonates. We failed to show differences in immune parameters or in infection and rehospitalization rates of the preterm infants analysed. Alongside previously published reports, our data suggest that red cell transfusions have a minimal impact on the immature immune system of the neonate.

Communicable Diseases↗

[Tolerability of once-daily-dosing of intravenous gentamicin in preterm neonates born at 32-37 weeks of gestation].

OBJECTIVE: Gentamicin is an important factor in the empiric therapy of premature babies with suspected invasive bacterial infection. The aims of the study were to assess the tolerability of short course of gentamicin in preterm neonates. PATIENTS AND METHODS: Preterm neonates aged 24 hours or less who were born at 32-37 weeks of gestation and weighed over 1500 grams were included in the study. Those infants suspected of having invasive non-CNS bacterial infection were assigned to treatment with ampicillin 50 mg/kg twice daily and either ODD (once daily dosing) or twice daily dosing (TDD) of gentamicin 5 mg/kg/day (17 and 18 patients, respectively). Neonates with shock, impaired renal function and known kidney, ear, and heart malformations, and metabolic disease were excluded from the study. At 72 to 96 hours of therapy, serum and urine creatinine, and sodium concentrations, peak (PGt) and though (TGt) serum levels of gentamicin, and urinary lysosyme secretion were measured. Fractional excretion of sodium (FeNa), and glomerullar filtration rate (GFR) were calculated for each infant. Audiometric evaluation was performed at 1 to 2 months of age. RESULTS: For the ODD and TDD groups respectively, the values of serum creatinine, FENa, GFR, and urinary lyzozim were similar. The mean SD PGt levels were 9.9 +/- 4.6 vs 5.9 +/- 1.9 g/ml (p < 0.04), and that of the TGt levels was 1.55 +/- 0.55 vs 2.4 +/- 0.9 micrograms/ml (p = 0.028), Ten (55.6%) vs 3(23.1%) of the TDD and ODD groups respectively had TGt levels above 2 micrograms/ml (p = 0.035). Audiometric evaluation was normal in all infants. CONCLUSIONS: Short course of ODD of gentamicin could be safe and potentially more effective in preterm babies.

Anti-Bacterial Agents↗

Early onset systemic Candida infection in extremely preterm neonates.

UNLABELLED: Classically, systemic Candida infections in preterm neonates occur at a mean age of 1 month. Over an 18-month period in a Regional Neonatal Intensive Care Unit we encountered seven cases of severe Candida infection, all in babies below 26 weeks gestation and weighing less than 0.75 kg. The median age of onset was 7 days (range 0-17), with thrombocytopenia, coagulopathy, hypotension, oedema, and skin breakdown being prominent features. CONCLUSION: The thin cutaneous barrier may contribute to early onset of systemic Candida infection in preterm infants. The characteristic skin appearance may assist early diagnosis.

Antifungal Agents↗

Quantification of L-type fatty acid binding protein in the urine of preterm neonates.

We measured urinary excretion of L-type fatty acid binding protein (L-FABP) in preterm neonates on days 1, 5-10, and 25-30 of life. Urinary L-FABP levels (expressed as the ratio to creatinine) in preterm neonates were considerably higher than those of healthy adults. They did not change significantly during the study period. Urinary L-FABP levels showed significant positive correlation with those of urinary N-acetyl-beta-D-glucosaminidase activity on day 1, and with those of 8-hydroxy-2'-deoxyguanosine on days 25-30. These results suggest that L-FABP is expressed in the neonatal kidney. Our results may also point to potential effects of proximal tubular damage and oxidative stress on urinary excretion of L-FABP.

8-Hydroxy-2'-Deoxyguanosine↗

Quantitation of glutathione S transferase-pi in the urine of preterm neonates.

BACKGROUND: Glutathione S transferases (GSTs) are widely distributed enzymes found in highly varying amounts in tissues of the human body. The enzyme GST-pi in urine has been used as a marker of renal distal tubular cell damage. The present study was intended to evaluate urinary excretion of GST-pi and its relationship to other renal markers and to the status of oxidative stress in preterm neonates. METHODS: Levels of urinary GST-pi, N-acetyl-beta-glucosaminidase (a marker of proximal tubular damage), albumin (a marker of glomerular damage) and 8-hydroxy-2'-deoxyguanosine (a marker of oxidative stress) and serum creatinine were measured in preterm neonates at 1 and 4 weeks of age. RESULTS: The results showed that urinary excretion of GST-pi is increased in preterm neonates compared with reported values for healthy adults. No significant relationship was detected between urinary GST-pi and other markers for renal function. Urinary GST-pi showed significantly positive correlation with urinary 8-hydroxy-2'-deoxyguanosine at 1 and 4 weeks. Sick neonates treated with supplemental oxygen and mechanical ventilation showed significantly higher levels of GST-pi as well as 8-hydroxy-2'-deoxyguanosine than clinically stable neonates did at 4 weeks. CONCLUSIONS: These results indicate the potential effect of systemic oxidative stress on urinary excretion of GST-pi. Further studies are necessary to explore the effect of oxidative conditions on expression of GST-pi in distal tubules in the human kidney.

8-Hydroxy-2'-Deoxyguanosine↗

Facilitated tucking: a nonpharmacologic comfort measure for pain in preterm neonates.

OBJECTIVE: To identify the effectiveness of "facilitated tucking," a nonpharmacologic nursing intervention, as a comfort measure in modulating preterm neonates' physiologic and behavioral responses to minor pain. DESIGN: Prospective, repeated measure, random sequencing, and experimental. SETTING: Level III neonatal intensive-care unit of a tertiary care university pediatric hospital. PARTICIPANTS: Thirty preterm neonates, 25-35 weeks gestation. INTERVENTIONS: Heart rate, oxygen saturation, and sleep state were recorded 12 minutes before, during, and 15 minutes after two heelsticks, one with and one without facilitated tucking. HYPOTHESIS: Premature neonates will have less variation in heart rate and hemoglobin oxygen saturation, shorter crying and sleep disruption times, and less fluctuation in sleep states in response to the painful stimulus of a heelstick with facilitated tucking than without. RESULTS: Neonates demonstrated a lower mean heart rate 6-10 minutes post-stick (p < 0.04), shorter mean crying time (p < 0.001), shorter mean sleep disruption time (p < 0.001), and fewer sleep-state changes (p = 0.003) after heelstick with facilitated tucking than without. CONCLUSION: Facilitated tucking is an effective comfort measure in attenuating premature neonates' psychologic and behavioral responses to minor pain.

Blood Specimen Collection↗

Relations between behavioral and cardiac autonomic reactivity to acute pain in preterm neonates.

OBJECTIVE: The purpose of this study was to assess relations and concordance between behavioral and physiologic reactivity to pain in preterm neonates at 32 weeks postconceptional age as a function of gestational age at birth. SETTING: Level III neonatal intensive care unit. DESIGN/PATIENTS: The study group comprised 136 preterm neonates (mean [range] birthweight, 1,020 g [445-1,500 g]: gestational age at birth, 28 weeks [23-32 weeks]) separated into three groups according to gestational age at birth as follows: 23 to 26 weeks (n = 48), 27 to 29 weeks (n = 52), and 30 to 32 weeks (n = 36). OUTCOME MEASURES: Reactivity to routine blood collection at 32 weeks postconceptional age was assessed using bedside-recorded behavioral and autonomic measures. Coders who were blinded to the study design scored behavioral responses (facial activity using the Neonatal Facial Coding System, sleep/waking state, and finger splay). Autonomic reactivity was assessed by change in heart rate and spectral analysis of heart rate variability (change in low-frequency and high-frequency power, and the ratio of low-frequency to high-frequency power during blood collection). RESULTS: Facial activity and state correlated moderately with change in heart rate across gestational age groups (r = 0.41-0.62). Facial activity and state did not correlate significantly with change in low-frequency and high-frequency power, or the ratio of low-frequency to high-frequency power (r = 0.00-0.31). Finger splay did not correlate with any autonomic recording (r = 0.03-0.41). Concordance between established biobehavioral measures of pain revealed individual differences. Although some neonates showed high behavioral but low physiologic reactivity, other neonates displayed the opposite reaction; however, the majority displayed concordant reactions. CONCLUSIONS: The study findings confirm the value of measuring domains independently, especially in neonates born at a very young gestational age.

Acute Disease↗

Plasma 6-keto prostaglandin F1 alpha and thromboxane B2 in sick preterm neonates.

To determine if vascular abnormalities in preterm neonates might be related to vasoactive prostaglandins, stable prostacyclin (6-KPGF1 alpha) and thromboxane A2 (T X B2) metabolites in arterial blood were measured at less than or equal to 6 hours after birth and at 24, 48, and 72 hours using a radioimmunoassay. Neonates of less than 32 weeks gestation (N = 26) were diagnosed as having either the idiopathic respiratory distress syndrome (IRDS, N = 15) or pulmonary edema (PE, N = 11), and were also grouped according to the presence or absence of intracranial hemorrhage (ICH, N = 11) or patent ductus arteriosus (PDA, N = 10). Initial plasma 6-KPGF1 alpha was greater in neonates with ICH (0.23 +/- 0.04 ng/ml, mean +/- SE) than without ICH (0.11 +/- 0.04, p less than 0.05). Neonates with both ICH and IRDS (N = 8) had significantly elevated T X B2 at all sampling times compared to neonates with IRDS and no ICH (N = 7). Both T X B2 and 6-KPGF1 alpha increased with time in those with major ICH. Among neonates without ICH, 7 with IRDS had higher initial 6-KPGF1 alpha (0.19 +/- 0.07 ng/ml) and lower T X B2 (0.15 +/- 0.04 ng/ml) than 8 with PE (0.04 +/- 0.01 and 0.37 +/- 0.09 ng/ml, respectively). The initial 6-KPGF1 alpha (0.024 + 0.003 ng/ml), measured in neonates with PE and without PDA or ICH (N = 6), was significantly less than the corresponding value in the other neonates (0.201 +/- 0.036 ng/ml) (N = 20).

6-Ketoprostaglandin F1 alpha↗

[Supplementary intravenous nutrition in term and preterm neonates (author's transl)].

16 term and preterm neonates received intravenous nutriton for at least three days. The dosage was 1--2 g amino acids, 1 g of fat, and 8--10 g glucose per kg body weight and day. Compatibility was investigated by daily determinations of the amino acid pattern in the serum and measurement of free fatty acids and triglycerides. All results were compared to five neonates who were fed completely orally from the first day of life. Leucine, methionine, proline, and valine levels were elevated during intravenous nutrition, but only the high methionine levels were regarded as a nutrional imbalance. Free fatty acids and triglycerides showed no significant differences as compared to the control group.

Amino Acids↗

[Aseptic meningitis after intrathecal infusion of a parenteral nutrition solution: examples of rare malpositions of central venous catheters in preterm neonates].

BACKGROUND: Central venous catheters are an indispensable part of intensive care. In the management of preterm neonates, these are introduced after puncture of a peripheral subcutaneous vein. The catheters are supposed to be pushed forward with the venous flow. A chest X-ray is usually performed for verification of the position of the catheter. Localization of the tip of the catheter is often very difficult because of its extremely small diameter. METHODS: A malposition of a central venous catheter resulting in intrathecal infusion of parenteral nutrition and subsequent aseptic meningitis in a preterm neonate is presented. Further cases of catheter malpositions leading to arthrography, arteriography and incorrect position in various parts of the venous system are discussed. DISCUSSION AND CONCLUSION: The case reports demonstrate that wire-guided central venous catheters are not only advanced by the forward blood flow but can also inadvertently end up in undesired sites and may thus induce serious side effects.

Catheterization, Peripheral↗

Liquid ventilation of human preterm neonates.

This report details the application of liquid perfluorochemical ventilation for investigational therapy in three human preterm neonates (gestational ages 28, 24, and 23 weeks) in whom conventional therapies for severe respiratory distress had failed. Liquid ventilation was performed without difficulty in each infant for two 3- to 5-minute cycles by means of gravity-assisted technique. Marked improvement in lung distensibility, without a change in cardiovascular status, occurred in all three infants after liquid ventilation; oxygenation improved in two. All infants died within 19 hours of liquid ventilation, and there was no evidence of retained perfluorochemical fluid in the lungs or pleural space. Death was probably related to the severity of lung disease before the initiation of liquid ventilation. This satisfactory initial outcome shows the feasibility and potential of this treatment of pulmonary dysfunction in the preterm neonate.

Airway Resistance↗

Effect of PaCO2 and haemoglobin concentration on day to day variation of CBF in preterm neonates.

The CBF was measured on the first three days of life in 22 mechanically ventilated, preterm neonates (mean gestational age 29.5 weeks) with simultaneous recordings of arterial carbon dioxide tension (PaCO2), arterial oxygen tension (PaO2), haemoglobin concentration (Hgb), haemoglobin oxygen saturation and mean arterial blood pressure (MABP). CBF infinity tended to increase slightly with age. The intra-individual variation of CBF infinity was positively related to changes in PaCO2 (p = 0.0004) and inversely related to changes in Hgb (p = 0.029). Neither PaO2 nor MABP achieved a significant relation to changes in CBF infinity. Thus, the mean CBF infinity -CO2 reactivity was calculated to 22.1% per kPa whereas CBF infinity increased by a mean of 11.9% per mM decrease of Hgb thereby providing a constant oxygen delivery to the brain. It is concluded that PaCO2 and Hgb have the expected effect on CBF infinity in preterm neonates even during respiratory distress shortly after birth.

Age Factors↗

Single-dose darbepoetin administration to anemic preterm neonates.

OBJECTIVE: Darbepoetin is longer acting and more potent than recombinant erythropoietin (rEpo). In certain situations, preterm neonates might benefit from rEpo, and for such patients darbepoetin would require fewer doses at a lower cost. However, the proper dose and dosing interval have not been established. STUDY DESIGN: We performed a prospective trial in two level III Neonatal Intensive Care Units. Patients <32 weeks gestation at birth, with a birth weight (BW) <1500 g, were eligible for participation if they were >21-days-old and had a hemoglobin (Hgb) concentration </or=10.5 g/dl. In all, 12 were to receive a single subcutaneous (s.c.) dose at either 1 or 4 microg/kg. Once before the dose was given, and at two preset intervals after, blood was obtained for immature reticulocyte fraction (IRF) and absolute reticulocyte count (ARC). Once before and at four preset intervals after, blood was obtained for pharmacokinetic studies. RESULTS: The 12 subjects had BWs of 1129+/-245 g (mean+/-SD), were 29.2+/-1.2 weeks gestation at delivery, and were 43+/-12 days old with an Hgb concentration of 9.6+/-1.0 g/dl when the darbepoetin was given. Six received 1 microg/kg and six 4 microg/kg. The IRF increased (p<0.05) as did the ARC (p<0.05). The increases in IRF were somewhat greater among the 4 microg/kg recipients (P=0.06). The highest recorded concentrations of drug occurred 6 to 12 hours after administration. The combined 6 and 12 hours values were 185+/-106 mU/ml in the 1 microg/kg group vs 597+/-238 in the 4 microg/kg group (p<0.002). The t(1/2) was 26 hours (range 10 to 50). The biovailability-normalized clearance was 19 ml/hour/kg (range 5 to 54). CONCLUSIONS: A single s.c. dose of darbepoetin given to preterm neonates accelerated effective erythropoiesis. The pharmacodynamic and pharmacokinetic findings suggest that darbepoetin dosing in neonates would require a higher unit dose/kg and a shorter dosing interval than are generally used for anemic adults.

Anemia, Neonatal↗

An elevated hematogenous photosensitizer in the preterm neonate.

PURPOSE: Human blood contains low levels of protoporphyrin IX (PP IX), a photoactive compound that produces reactive oxygen species when exposed to light. It has been proposed that photoactivation of PP IX and subsequent generation of potentially tissue-damaging reactive oxygen may be a mechanism of retinal injury in retinopathy of prematurity (ROP). The purpose of this study is to determine an association between blood PP IX level and infant birth-weight and gestational age. METHODS: Erythrocyte PP IX levels were measured from the umbilical cord blood of 31 neonates, both full term and preterm. Birthweights and gestational ages were recorded. RESULTS: PP IX levels in infants weighing < 1000 grams (n = 7) average 200 micrograms/dl, which is significantly higher than PP IX levels in infants weighing > 1000 grams (125 micrograms/dl, n = 24; P < 0.02). CONCLUSION: Elevated PP IX levels may place preterm neonates at increased risk for photosensitizing retinal injury.

Fetal Blood↗

Circulating GH isoforms and GH bioactivity in preterm neonates.

Among the molecular variants of human GH, the monomeric 22-kD is the predominant isoform, whereas the 20-kD is the second most abundant isoform. Because little is known on the pattern of human GH isoforms in the early postnatal period, we evaluated serum levels of 22-kD GH by an immunofluorometric assay and of 20-kD GH by an ELISA using an anti-20-kD antibody, and measured GH bioactivity with the Nb2 cell bioassay in 19 preterm neonates (gestational age, 32 +/- 0.5 wk; mean +/- SEM) on the fourth and 15th days of life. As control subjects, we studied 19 full-term neonates (gestational age, 39 +/- 0.3 wk) on the fourth day of life and 20 healthy adults, aged 20 +/- 0.3 y. Four-day-old preterm neonates showed significantly higher serum values of 20-kD GH (0.99 - 0.14 ng/mL) than full-term neonates (0.33 +/- 0.07 ng/mL; p < 0.001) and adults (0.09 +/- 0.02; p < 0.0001). Likewise, 22-kD GH and GH levels by Nb2 cell bioassay were also significantly higher (p < 0.001) in preterm than in full-term neonates and young adults. A significant decrease (p < 0.01) in 20-kD, 22-kD, and Nb2-determined GH was observed in preterm neonates on the 15th day of life The percentage of the 20-kD isoform was similar in the preterm infants at the fourth and 15th day, in full-term-infants, and in adults (2.7%, 2.7%, 2.8%, and 3.16%, respectively). Our results indicate that 20-kD GH serum levels change throughout life as regards total amount, but not as regards percentage.

Adult↗

Central-peripheral temperature difference, blood pressure, and arginine vasopressin in preterm neonates undergoing volume expansion.

AIM: To examine the effect of intravascular volume expansion for the treatment of hypovolaemia in sick preterm neonates. METHODS: An intravenous infusion of 20 ml per kg of 4.5% albumin was given to 14 preterm neonates. The effects on systolic blood pressure, central peripheral temperature difference (c-pT), and plasma arginine vasopressin concentration (pAVP) were measured. RESULTS: Thirteen babies showed a rise in systolic blood pressure. The six babies with the highest initial values of pAVP and c-pT showed a fall in both of these after infusion. The babies with lower initial pAVP (below 4 pmol/l) showed either a rise (two) or no change (six) after albumin infusion. There was a significant correlation between c-pT and log pAVP before (r2 = 0.61; p < 0.05) and after infusion (r2 = 0.45; p < 0.05). CONCLUSIONS: Plasma AVP concentration is related to c-pT in unwell preterm newborns. This study suggests that clinical assessment of hypovolaemia in preterm newborns is poor and could be improved by using c-pT.

Arginine Vasopressin↗

Physiological, hormonal, and behavioral responses to a single fentanyl dose in intubated and ventilated preterm neonates.

OBJECTIVE: To study the responses of ventilated preterm neonates to a single dose of opioid. STUDY DESIGN: In a randomized, double-blind, controlled trial, 22 mechanically ventilated preterm infants (< or = 32 weeks) were observed before medication and at 30 and 60 minutes after administration of fentanyl (3 micrograms/kg) or placebo. Heart rate, blood pressure, arterial blood gases, ventilator settings, and behavioral measures (Neonatal Facial Coding System and Modified Postoperative Comfort Score) were recorded during each period. Blood cortisol, growth hormone, glucose, and lactate were measured before and at 60 minutes after analgesia. Behavioral measures were assessed at the bedside and from video films recorded during each observation period. RESULTS: Patients presented high basal levels of cortisol, growth hormone, and lactate. Behavioral scales indicated the presence of pain before any medication. In the fentanyl group, the maximum and minimum heart rate decreased and growth hormone level increased after analgesia. At the video analysis of behavioral measures, postoperative comfort score increased and neonatal facial coding system score decreased in the fentanyl group. CONCLUSION: Single doses of fentanyl analgesia can reduce the physiologic/behavioral measures of pain and stress associated with mechanical ventilation in preterm infants.

Analgesia↗

[Cerebrovascular disorders in preterm neonates].

AIM: To review the etiology, pathogenesis, clinical manifestations, diagnosis and treatment of cerebrovascular disorders (CVD) in preterm neonates. DEVELOPMENT: The germinal matrix-intraventricular hemorrhage (GM-IVH) is the most frequent intracranial hemorrhage. The pathogenesis includes intravascular, vascular and extravascular factors. The neuropathologic lesion is the hemorrhage within the subependymal GM. There are four degrees of severity. Clinical manifestations include three syndromes: catastrophic, saltatory and silent. Treatment is prophylactic. Periventricular hemorrhagic infarct is of venous origin, might be associated to GM-IVH and is difficult to differentiate from periventricular leukomalacia (PVL). Cerebellar hemorrhage frequency increases with decreasing gestational age. It may be asymptomatic or manifest with a non-specific neurologic picture. PVL is the most important ischemic lesion. Its pathogenesis includes anatomic, physiologic, maturational, biochemical, infectious and immunologic factors. The neuropathologic lesion is focal necrosis in the terminal distribution of the long penetrating arteries. Treatment is prophylactic. Other ischemic lesions are ischemic arterial infarct, cerebellar infarct, telencephalic leukoencephalopathy and pontosubicular necrosis. CVD diagnostic tests include cerebral ultrasound, computed tomography, magnetic resonance imaging and spectroscopy and electroencephalogram. Mortality of some CVD is high and some others are associated with a high risk of cerebral palsy and cognitive deficits. CONCLUSION: CVD are common in preterm neonates and represent an important cause of neurologic disease in the child.

Brain Ischemia↗