Nutrition of preterm infants in relation to bronchopulmonary dysplasia.

BACKGROUND: The pathogenesis of bronchopulmonary dysplasia (BPD) is multifactorial. In addition to prenatal inflammation, postnatal malnutrition also affects lung development. METHODS: A retrospective study was performed to analyse during the first two weeks of life the total, enteral and parenteral nutrition of premature infants (<31 weeks, birth weight ≤1500 g) born between 08/04 and 12/06. RESULTS: Ninety-five premature infants were analysed: 26 with BPD (27 ± 1 weeks) and 69 without BPD (28 ± 1 weeks). There was no statistical significant difference in the total intake of fluids, calories, glucose or protein and weight gain per day in both groups. The risk of developing BPD was slightly increased in infants with cumulative caloric intake below the minimal requirement of 1230 kcal/kg and a cumulative protein intake below 43.5 g/kg. Furthermore, the risk of developing BPD was significantly higher when infants had a cumulative fluid intake above the recommended 1840 ml/kg. In infants who developed BPD, the enteral nutrition was significantly lower than in non-BPD infants [456 ml/kg (IQR 744, 235) vs. 685 (IQR 987, 511)]. Infants who did not develop BPD reached 50% of total enteral feeding significantly faster [9.6 days vs. 11.5]. CONCLUSIONS: Preterm infants developing BPD received less enteral feeding, even though it was well compensated by the parenteral nutrient supply. Data suggest that a critical minimal amount of enteral feeding is required to prevent development of BPD; however, a large prospective clinical study is needed to prove this assumption.

Variations of Apgar score of very low birth weight infants in different neonatal intensive care units.

OBJECTIVE: The Apgar score should be an objective method to assess the state of newborns; however, its applicability in preterm infants is hampered by large variations among different observers. The study tested whether physicians that give low scores to written case descriptions also apply lower scores to preterm infants. PATIENTS AND METHODS: Descriptions (BMJ 2004; 329: 143-4) were sent to 14 neonatal units. Physicians were asked to evaluate the Apgar (case score). From seven units Apgar scores of all very low birth weight infants (VLBW) born between January 2004 and December 2006 were obtained from charts (clinical score). RESULTS: In total, 121 physicians from 14 institutions (median 9, range 3-15) replied: 24 residents with <6-month and 28 with >6-month neonatal experience, and 69 consultants. The assessment of the case scores was very heterogeneous with large variations in respiration, muscle tone and reflexes. Clinical scores were obtained from 1000 VLBW infants. The score depended on the gestational age, with a median of 4 at 24 and 7 at 27 weeks. With one exception, centres that assigned low case scores had also low clinical scores. CONCLUSION: There is considerable variation in assigning Apgar scores. Definitions are required to apply the Apgar score to infants under clinical conditions such as preterm delivery, resuscitation or artificial ventilation.

Vascular endothelial growth factor as marker for tissue hypoxia and transfusion need in anemic infants: a prospective clinical study.

OBJECTIVE: Oxygen-carrying capacity of blood is reduced in anemic infants because of low hemoglobin levels. Red blood cell transfusions become necessary if low hematocrit causes tissue hypoxia. No reliable parameters exist for detecting chronic tissue hypoxia. Vascular endothelial growth factor is upregulated by hypoxia; hence, elevated vascular endothelial growth factor levels may be a marker for tissue hypoxia and may indicate the need for red blood cell transfusions. METHODS: In a prospective study, plasma vascular endothelial growth factor levels were measured in 3 groups of infants suspected of requiring red blood cell transfusions to find a vascular endothelial growth factor cutoff value indicative of tissue hypoxia. The 3 groups were acute anemic (an episode of acute bleeding [hematocrit drop > 5%] per day); chronic anemic (hematocrit drop < 5% per day); and nontransfused (hematocrit drop < 5% per day) but not meeting clinical criteria for a transfusion. Blood was sampled before transfusion and again 48 hours after transfusion if required. Plasma vascular endothelial growth factor and erythropoietin concentrations were measured. RESULTS: Vascular endothelial growth factor concentrations were lower in acutely anemic compared with chronically anemic infants, whereas erythropoietin levels did not differ between these groups. The vascular endothelial growth factor concentration was <140 pg/mL in all acutely anemic infants, and this was deemed the threshold level indicating sufficient tissue oxygenation in subsequent analysis. We found that 30% of chronically anemic and 43% of nontransfused infants had vascular endothelial growth factor levels of >140 pg/mL. In transfused infants, with elevated vascular endothelial growth factor levels, red blood cell transfusion resulted in lowering of vascular endothelial growth factor concentrations. CONCLUSIONS: Vascular endothelial growth factor concentrations of >140 pg/mL may indicate insufficient oxygen delivery to tissues and may serve as a marker of the need for transfusion or of tissue hypoxia in other diseases.

Comparison of 2-h versus 3-h enteral feeding in extremely low birth weight infants, commencing after birth.

AIM: Immaturity is associated with problems in enteral nutrition of extremely low birth weight (ELBW) infants. Different time intervals between single feedings are used; however, no data are available to show a benefit of either regime. METHODS: In January 2001 enteral feeding regime was changed from 2-h to 3-h intervals. In a retrospective study charts were analysed for all ELBW infants during a period of 2 years prior (01/99-12/00) and after (08/01-07/03) changing the feeding regime. RESULTS: Forty-two in the 2-h group (gestational age 27 +/- 2.1, birth weight 797 +/-150) and 32 infants in 3-h (GA 26.9 +/- 1.8 weeks, BW 809 +/- 148 g) were included. Median (range) time until complete enteral feeding (26 (7 to 69) vs. 20 (12 to 58) days) was not statistical different. There were no differences with respect to enteral morbidity (NEC, abdominal surgery, feeding intolerance), length of stay (84 +/- 23 vs. 86 +/- 26 days), growth parameters or weight at discharge. Total duration of phototherapy and average length of continuous positive airway pressure (CPAP) support were significantly (p < 0.01) longer in the 3-h feeding group. CONCLUSION: Weight gain and time until complete enteral nutrition are similar in 2-h and 3-h feeding regimes. Data suggest an advantage of 2-h feedings concerning the length of CPAP and phototherapy.

Human cytomegalovirus reactivation during lactation and mother-to-child transmission in preterm infants.

In a clinical trial, the incidence of cytomegalovirus reactivation in breastfeeding mothers and transmission to their preterm infants were studied. Breast milk from 73 mothers as well as urine and tracheal and pharyngeal aspirates from their 89 infants were screened weekly for human cytomegalovirus (HCMV) DNA during the first 2 months after delivery. Of the 73 mothers, 48 (66%) were positive for HCMV DNA in the lactating breast. HCMV reactivation could be confirmed for 19 of 20 (95%) immunoglobulin G-positive mothers. Of the eight immunoglobulin G-negative mothers one was positive for HCMV DNA in breast milk. In only 2 out of 13 seropositive mothers with HCMV DNA in breast milk could viral DNA be detected in the peripheral blood. HCMV mother-to-child transmission was concluded for 20 of the 48 (42%) mothers positive for DNA or 7 of 19 (37%) seropositive for HCMV and positive for HCMV DNA in breast milk and one of one mother seronegative for HCMV but positive for HCMV DNA in breast milk. One mother transmitted the virus to her twins. In addition, one infant acquired postnatal HCMV infection despite the mother's being negative for HCMV DNA in breast milk; altogether, we found 22 infants with HCMV infection. In 13 of these 22 infants, virus infection occurred definitively postnatally; two of them developed severe symptomatic HCMV infection. HCMV-infected infants demonstrated higher incidences of amniotic infection, respiratory distress syndrome, bronchopulmonary dysplasia, and retinopathia praenatalis than noninfected infants, however, the differences were not statistically significant. In summary, our study confirmed a very high incidence of HCMV reactivation in mothers during lactation and a significant risk of transmission to preterm infants with the possibility of severe disease in these babies.