Effects of blood transfusion on regional tissue oxygenation in preterm newborns are dependent on the degree of anaemia.

AIM: Most of the preterm infants are transfused at least once during their stay in the neonatal intensive care unit (NICU). The aims of this study were to demonstrate if packed red blood cell (pRBC) transfusion modulates regional (cerebral, abdominal, renal) tissue oxygen saturation measured by near-infrared spectroscopy (NIRS) and to demonstrate if we can use NIRS to guide transfusion decisions in neonates. METHODS: A multi-probe NIRS device was applied to anaemic preterm infants of gestational age <33 weeks for 30-60 min before and 24 h after pRBC transfusion. We evaluated the results separately in the subgroup with a pre-transfusion haemoglobin (Hb) < 8 g/dL. Cerebral, abdominal and renal tissue oxygen saturation (rSO2 ) and abdominal/cerebral, abdominal/renal and renal/cerebral rSO2 ratios before and 24 h after transfusion were compared. RESULTS: There was no significant difference in cerebral rSO2 and abdominal/renal rSO2 ratios before and 24 h after transfusion, but abdominal and renal rSO2 and abdominal/cerebral and renal/cerebral rSO2 ratios at the 24th h following transfusion increased significantly. This increase was observed in the subgroup with pre-transfusion Hb < 8 g/dL. Although statistically significant, the increase in renal oxygenation was within the limits of variability. CONCLUSIONS: The increase in tissue oxygenation in abdominal region after pRBC transfusion suggests decreased tissue oxygenation of intestines during severe anaemia despite cerebral oxygenation being maintained at that particular Hb level. The impact of the increase on renal oxygenation with pRBC transfusion is unclear and might need further investigation. Increase in abdominal rSO2 may cause reperfusion injury, oxidative damage and trigger necrotising enterocolitis.

Effects of Volume Guaranteed Ventilation Combined with Two Different Modes in Preterm Infants.

BACKGROUND: Volume-controlled ventilation modes have been shown to reduce duration of mechanical ventilation, incidence of chronic lung disease, failure of primary mode of ventilation, hypocarbia, severe intraventricular hemorrhage, pneumothorax, and periventricular leukomalacia in preterm infants when compared with pressure limited ventilation modes. Volume-guarantee (VG) ventilation is the most commonly used mode for volume-controlled ventilation. Assist control, pressure-support ventilation (PSV), and synchronized intermittent mandatory ventilation (SIMV) can be combined with VG; however, there is a lack of knowledge on the superiority of each regarding clinical outcomes. Therefore, we investigated the effects of SIMV+VG and PSV+VG on ventilatory parameters, pulmonary inflammation, morbidity, and mortality in preterm infants. METHODS: Preterm infants who were born in our hospital between 24-32 weeks gestation and needed mechanical ventilation for respiratory distress syndrome were considered eligible. Patients requiring high-frequency oscillatory ventilation for primary treatment were excluded. Subjects were randomized to either SIMV+VG or PSV+VG. Continuously recorded ventilatory parameters, clinical data, blood gas values, and tracheal aspirate cytokine levels were analyzed. RESULTS: The study enrolled 42 subjects. Clinical data were similar between groups. PSV+VG delivered closer tidal volumes to set tidal volumes (60% vs 49%, P = .02). Clinical data, including days on ventilation, morbidity, and mortality, were similar between groups. Chronic lung disease occurred less often and heart rate was lower in subjects who were ventilated with PSV+VG. The incidence of hypocarbia and hypercarbia were similar. Interleukin-1ß in the tracheal aspirates increased during both modes. CONCLUSION: PSV+VG provided closer tidal volumes to the set value in ventilated preterm infants with respiratory distress syndrome and was not associated with overventilation or a difference in mortality or morbidity when compared to SIMV+VG. Therefore, PSV+VG is a safe mode of mechanical ventilation to be used for respiratory distress syndrome.

Iloprost Instillation in Two Neonates with Pulmonary Hypertension.

Pulmonary hypertension may coexist with certain diseases in neonates. Iloprost inhalation is one of the treatments which cause selective pulmonary vasodilatation. Inhalation is not an easy way of drug administration in mechanically ventilated infants; as some exhibit desaturations during inhalation. Moreover, inhalation of drug requires cessation of mechanical ventilation, if patient is on high frequency oscillatory ventilation. We presented two patients with pulmonary hypertension; term baby with congenital diaphragmatic hernia and preterm baby with respiratory distress syndrome; who had iloprost instillation during mechanical ventilation treatment. Iloprost instillation was well tolerated with no side effects in the term patient with diaphragmatic hernia; whereas severe blood pressure fluctuations were observed in the preterm infant. This report may courage administration of iloprost in term neonates with resistant pulmonary hypertension.

Perfusion index assessment during transition period of newborns: an observational study.

BACKGROUND: Perfusion index (PI) is becoming a part of clinical practice in neonatology to monitor peripheral perfusion noninvasively. Hemodynamic and respiratory changes occur in newborns during the transition period after birth in which peripheral perfusion may be affected. Tachypnea is a frequent symptom during this period. While some tachypneic newborns get well in less than 6 h and diagnosed as "delayed transition", others get admitted to intensive care unit which transient tachypnea of newborn (TTN) being the most common diagnosis among them. We aimed to compare PI of neonates with TTN and delayed transition with controls, and assess its value on discrimination of delayed transition and TTN. METHODS: Neonates with gestational age between 37 and 40 weeks who were born with elective caesarian section were included. Eligible neonates were monitored with Masimo Set Radical7 pulse-oximeter (Masimo Corp., Irvine, CA, USA). Postductal PI, oxygen saturation and heart rate were manually recorded every 10 s for 3 min for two defined time periods as 10th minute and 1st hour. Axillary temperature were also recorded. Newborn infants were grouped as control, delayed transition, and TTN. RESULTS: Forty-nine tachypneic (TTN; 21, delayed transition; 28) and 30 healthy neonates completed the study. PI values were similar between three groups at both periods. There were no correlation between PI and respiratory rate, heart rate, and temperature. CONCLUSION: PI assessment in maternity unit does not discriminate TTN from delayed transitional period in newborns which may indicate that peripheral perfusion is not severely affected in either condition.

The effects of breast milk storage and freezing procedure on interleukine-10 levels and total antioxidant activity.

OBJECTIVE: To compare interleukine-10 (IL-10) and total antioxidant capacity (TAC) levels after breast milk storage by studying premature and term mothers' colostrum and mature milk and by analyzing those levels relative to gestational week. METHODS: Fifty-four colostrum and mature breast milk samples were collected from both premature and term mothers. The samples were divided into three groups based on the time of analysis: fresh milk, at +4 °C for 72 h, and at -20 °C for 14 d. The IL-10 and TAC levels were measured quantitatively. RESULTS: Fresh colostrum and mature milk had similar IL-10 levels. Term mothers' fresh-colostrum TAC levels were higher than their mature milk. The mature milk of the premature mothers' had higher TAC levels than that of term mothers. Storage did not affect the IL-10 levels of breast milk, but fresh milk antioxidant capacity halved after 72 h and 14 d. Colostrum IL-10 and TAC levels did not correlate with gestational week. Mature milk IL-10 levels did not correlate with gestational week, but TAC levels negatively correlated with gestational week (r: -0.61: p < 0.01). CONCLUSIONS: The milk stored for 72 h at +4 °C and for 14 d at -20 °C did not maintain the same TAC levels as the fresh samples. This should be considered especially for sick infants who need more antioxidant capability in neonatal units.

Analysis of serum γ-glutamyl transferase levels in neonatal intensive care unit patients.

OBJECTIVES: Gamma-glutamyl transferase (GGT) is commonly measured in newborn infants as a sensitive liver function test; however, reference ranges are mostly based on early studies, including relatively small number of patients. The aim of this study was to emphasise recently changed GGT values because of changed newborns profile admitted to neonatal intensive care units (NICUs) and establish new cross-sectional reference ranges for the serum GGT levels in a cohort of neonates between 26 and 42 weeks' gestational age in 1 centre. METHODS: From January 1, 2010 to December 31, 2012, liver function tests including serum GGT measurements were performed in 705 newborns who were admitted to NICUs because of different aetiologies at Gazi University School of Medicine Hospital, Ankara, Turkey. Infants with Apgar score <8 at the fifth minute, any metabolic or liver disease, cholestasis, congenital infection, culture-proven sepsis, elevated serum aminotransferases, and who were treated with phenobarbital were excluded. Clinical and laboratory data of 583 neonates were analysed retrospectively. GGT was measured by enzymatic method using the Abbott Architect C16000 autoanalyser. Mean, 2.5th, and 97.5th percentiles were used to express the reference range data. RESULTS: Four hundred sixty-one GGT values of 200 preterm infants and 501 GGT values of 383 term infants during the first 28 days after birth were analysed. Serum GGT levels of preterm infants in the first 7 days and between 8 and 28 days after delivery were (mean±standard deviation; 141.81±88.56 U/L and 131.17±85.53 U/L) similar to term infants (139.90±86.46 U/L and 144.56±86.51 U/L), respectively (P=0.649 and P=0.087). Serum GGT levels were found to be significantly higher in male infants (no need of query) (145.98±93.68 U/L) than female infants (132.18±78.97 U/L) (P=0.035), and infants born vaginally (152.24±90.71 U/L) also had higher serum GGT activity than those born by caesarean section (135.38±85.37 U/L) (P=0.005). CONCLUSIONS: A new reference range for serum GGT levels that is higher than previous reference values can identify neonates with truly abnormal results and prevent unnecessary interventions.

The effects of surfactant on oxygenation in term infants with respiratory failure.

OBJECTIVE: The objective of the study was to evaluate the effects of exogenous surfactant on respiratory indices in term infants with respiratory failure. METHODS: Consecutive 18 mechanically ventilated term infants, who received a single dose of exogenous surfactant were retrospectively included into the study. The respiratory outcome of surfactant rescue therapy was evaluated by comparing respiratory indices before and six hours after surfactant administration. FINDINGS: Median oxygenation index (OI), mean alveolar pressure (MAP) and fraction of inspired oxygen (FiO2) values were significantly decreased (P<0.001); median arterial oxygen partial pressure (PaO2), arterial oxygen saturation (SaO2) and PaO2/FiO2 values were significantly increased six hours after surfactant treatment (P<0.001). CONCLUSION: Rescue therapy with surfactant was found to be effective in the improvement of early respiratory indices in term infants with respiratory failure.

Are the neonatal outcomes similar in large-for-gestational age infants delivered by women with or without gestational diabetes mellitus?

BACKGROUND: Infants are considered large for gestational age (LGA) if their birth weight is greater than the 90th percentile for gestational age and they have an increased risk for adverse perinatal outcomes. Maternal diabetes is one of the factors affecting birthweight. However there are limited data on the perinatal outcomes of infants of gestational diabetic mothers. The aim of the present study was to compare the neonatal outcomes of LGA infants delivered by women with and without gestational diabetes mellitus. METHODS: This was a retrospective study of LGA infants of ≥36 weeks of gestation born at the Gazi University Medical School Hospital during the period of 2006-2009. Neonatal outcomes included hypoglycemia and polycythemia in the early neonatal period and hospital admissions. The Chi-square and Student's t test were used for comparing variables. RESULTS: Seven hundred eligible infant-mother pairs were enrolled in the study. Eighty-seven of them (12.4%) were infants of gestational diabetic mothers and 613 (87.6%) were infants of non-diabetic mothers. The incidence of hypoglycemia at the first hour was higher in infants of diabetic mothers (12.8%) than in infants of non-diabetic mothers (5.3%) (P=0.014). Polycythemia was also more frequently observed in infants of the gestational diabetic mothers (9.3%) than in infants of the non-diabetic mothers (3.0%) (P=0.010). Although overall hospital admission rates were not different between the two groups, infants of diabetic mothers were more likely to be admitted because of resistant hypoglycemia (P=0.045). CONCLUSIONS: The results of this study suggested that LGA infants of mothers with gestational diabetes mellitus were at a greater risk for hypoglycemia and polycythemia in the early neonatal period than LGA infants of nondiabetic mothers.

Soluble vascular endothelial growth factor receptor 1 in human breast milk.

BACKGROUND/AIMS: Vascular endothelial growth factor (VEGF) is a potent proangiogenic protein that activates VEGF receptor (VEGFR-1, VEGFR-2) tyrosine kinases expressed by vascular endothelial cells. A soluble truncated form of VEGFR-1 (sVEGFR-1) binds to VEGF as strongly as full-length VEGFR-1 and inhibits VEGF activity. sVEGFR-1 can be detected in mouse and human plasma but in human milk sVEGFR-1 has not been described previously. METHODS: We measured sVEGFR-1 and VEGF in human milk and examined how the concentration varied with gestational age and the duration of lactation after birth. Human milk samples were collected from 29 mothers of preterm (<37 weeks) and from 29 mothers of term (>38 weeks) infants at days 3, 7 and 28 postpartum. RESULTS: The sVEGFR-1 and VEGF concentrations were greater in the human milk of mothers of preterm compared to term neonates (p < 0.05). Furthermore, the concentrations of sVEGFR-1 and VEGF were decreasing during postpartum days 3, 7 and 28. The concentration of sVEGFR-1 showed a positive correlation with the concentration of VEGF in human milk (r = 0.479 and p < 0.001). CONCLUSION: sVEGFR-1 is present in human milk and has a role in angiogenesis.

Glycemic levels with glucose loading test during pregnancy and its association with maternal and perinatal outcomes.

OBJECTIVE: To evaluate the association between glycemic levels with glucose loading test during pregnancy and maternal and perinatal outcomes. METHODS: Retrospective analysis of 2059 singleton pregnancies screened for gestational diabetes mellitus at Gazi University Faculty of Medicine, Department of Obstetrics and Gynecology between January 2004 and December 2006 was conducted. Sensitivity and specificity of the 50 g glucose loading test was calculated for different cut-off values in our population. Maternal and perinatal outcomes in different groups with different results after screening test were compared. RESULTS: An increase in cut-off value from 140 to 145 mg/dl seems to be associated with a significant increase in specificity along with a tolerable decrease in sensitivity. A cut-off value of 147.5 mg/dl is associated with a higher specificity and a slightly lower sensitivity. However, the cut-off value 150 mg/dl seems to be associated with a significant decrease in sensitivity. As for the upper limit, a cut-off value of 180 mg/dl is associated with a 90% specificity and a cut-off value of 200 mg/dl is associated with a 99% specificity. A 100% specificity could be reached only after a cut-off value of 221 mg/dl. A GLT value of 180 mg/dl or higher was found to be associated with poor maternal and fetal outcomes, regardless of the result obtained after the diagnostic test. CONCLUSION: Results obtained after 50 g GLT should be evaluated separately for each patient and the diagnostic test which is time-consuming, uncomfortable and expensive can be omitted up to a cut-off value of 147.5 mg/dl, especially for those patients with no risk factors. Besides, a GLT value of 180 mg/dl or higher proves the diagnostic test unnecessary as these patients are associated with unfavorable perinatal and fetal outcomes.