Rosita S. Pildes

Plasma glucose values in normal neonates: A new look

Current standards for glucose concentration in neonates have been determined in whole blood and translated into plasma values on the basis that plasma glucose values are 12% to 15% higher than those in whole blood. 1 In addition, the standards 2 are based on birth weight because the concept of gestational age was not fully appreciated until the mid-1960s. Moreover, changes in maternal and fetal monitoring techniques, administration of glucose-containing solutions during labor and delivery, and early feeding of neonates may significantly alter blood glucose concentrations during the first week of postnatal life. This study was undertaken with the hypotheses that glucose values in normal neonates may be different from those previously defined and that neonatal hypoglycemia may need to be redefined. METHODS

Early postnatal dexamethasone therapy in premature infants with severe respiratory distress syndrome: A double-blind, controlled study

To determine whether early (less than or equal to 12 hours) postnatal dexamethasone therapy would facilitate removal of the endotracheal tube and improve outcome in premature infants with severe respiratory distress syndrome, we conducted a double-blind, controlled study of 57 infants whose birth weights were less than 2000 gm. The placebo (n = 29) and treated (n = 28) groups were comparable in birth weight (mean +/- SD: 1273 +/- 323 vs 1318 +/- 359 gm), gestational age (30.1 +/- 2.1 vs 30.8 +/- 2.7 weeks), postnatal age (8.7 +/- 3.1 vs 8.5 +/- 3.1 hours), and pulmonary function at the start of the study. The dose of dexamethasone was 1.0 mg/kg/day for 3 days and then was progressively decreased for 12 days. Infants in the dexamethasone group had significantly higher pulmonary compliance, tidal volume, and minute ventilation, and required lower mean airway pressure for ventilation than infants in the placebo group. The endotracheal tube was successfully removed from more infants in the dexamethasone group (16/28 vs 8/29; p less than 0.025). Nineteen infants (65%) in the placebo group and 11 (39%) in the dexamethasone group (p less than 0.05) had lung injuries. Dexamethasone therapy was associated with a temporary increase in blood pressure and plasma glucose concentration and a delay in somatic growth. We conclude that early postnatal dexamethasone therapy improves pulmonary status, facilitates removal of the endotracheal tube, and minimizes lung injuries in premature infants with severe respiratory distress syndrome.

Intravenous indomethacin therapy in premature infants with persistent ductus arteriosus—a double-blind controlled study

A double-blind controlled trial of intravenous indomethacin therapy was performed using a group of 55 premature infants (27 placebo, 28 indomethacin) with a significant persistent ductus arteriosus. Indomethacin administration at a mean postnatal age of 8.9 days was followed by a significant effect on PDA in 89%; 75% of successes were attributable to indomethacin and 25% to spontaneous effects, an improvement by indomethacin of 86% in infants not undergoing spontaneous improvement. The short-term side effects of indomethacin were transient; urinary output and serum sodium concentration decreased and serum potassium concentration increased. Indomethacin administration was associated with a decreased need for assisted ventilation and a decreased need for surgical closure of PDA. There was no significant difference between the placebo and indomethacin groups in mortality and bronchopulmonary dysplasia morbidity. The infants who developed BPD had higher RDS scores and lower PO2 values, requiring higher FIO2s within four hours of birth than those who did not develop BPD, indicating a more severe underlying pulmonary disability present birth.

Penicillin in Infants Weighing Two Kilograms or Less with Early-Onset Group B Streptococcal Disease

We studied the effect of penicillin on early-onset Group B streptococcal disease over a 52-month period in neonates who were at high risk of infection. Shortly after birth, 1187 neonates weighing 2000 g or less had blood samples taken for cultures and were randomized into an early-treatment group (given intramuscular penicillin G within 60 minutes of birth) or a control group. The incidence of early-onset disease was 20 per 1000 live births (24 of 1187); the number of infants in the early-treatment group who had disease (10 of 589) was similar to that in the control group (14 of 598). The fatality rates were similar in both groups (6 of 10 vs. 8 of 14). Cultures from blood obtained with one hour of birth were positive in 21 of the 24 infants with disease; 22 of the 24 were symptomatic within four hours of birth. Thus, infection was well established before the first hour of postnatal life. At autopsy, gram-positive cocci were seen in lung sections of four infants in whom cultures of blood obtained after treatment had been sterile; this indicates that giving routine antibiotic therapy before culture samples are obtained can obscure bacteriologic diagnosis. We conclude that penicillin given at birth to neonates weighing 2000 g or less does not prevent early-onset streptococcal disease or reduce excess mortality associated with disease.

Juvenile diabetes mellitus, a deficiency in insulin.

The plasma insulin, growth hormone, nonesterified fatty acids and glucose responses to the oral ingestion of glucose, the intravenous administration of tolbutamide and the infusion of arginine were studied in fourteen newly diagnosed juvenile diabetic children. Fasting plasma insulin levels did not differ significantly between diabetic and normal children, although the mean fasting blood glucose level of the diabetic children was threefold greater than that of the normal subjects No detectable plasma insulin response was observed in the diabetic subjects during all three tests. Fasting plasma growth hormone levels and plasma growth hormone responses were similar in both normal and diabetic children. The fasting free fatty acid level of the diabetic children was significantly higher than in normal children, but fell during all three tests. With use of a variety of sensitive procedures, no antibodies to human insulin were demonstrable in the sera of newly diagnosed juvenile diabetics.

Hypoglycemia in infancy and childhood

Hypoglycemia is a medical emergency in the newborn nursery. The requirements for glucose homeostasis, definition of hypoglycemia, classification of hypoglycemia (increased glucose utilization versus decreased glucose production), diagnostic evaluation and management will be presented. Clinical cases will be used to illustrate important disorders.

Furosemide prevents the renal side effects of indomethacin therapy in premature infants with patent ductus arteriosus

To determine if furosemide would prevent the renal side effects of indomethacin therapy in premature infants with patent ductus arteriosus, 19 premature infants were randomized into two groups: nine received indomethacin alone, and ten received indomethacin followed immediately by furosemide. There was no significant difference between the groups in birth weight, gestational age, postnatal age, and in cardiopulmonary or renal status at the time of study. Infants who received indomethacin and furosemide had significantly higher urine output (P less than 0.05), higher FENa and FECl (P less than 0.01), and higher glomerular filtration rate (P less than 0.05) than those of infants who received indomethacin alone. Seven infants in each group responded to indomethacin therapy with disappearance of PDA murmur and improvement of cardiovascular status. The results of this study suggest that furosemide may prevent the renal side effects of indomethacin therapy and yet not affect the efficacy of indomethacin in the closure of a PDA.

Absorption of iodine in the neonate following topical use of povidone iodine

Topical application of povidone iodine on the umbilical cord and normal intact skin of newborn infants resulted in significantly elevated plasma iodine levels. High iodine levels were also found in two neonates who had povidone iodine applied to denuded skin. No significant alteration in thyroid function was seen. The possible toxic manifestations of high plasma iodine levels are discussed.

Transient neonatal pustular melanosis.

Newborn infants were observed with vesicopustular and pigmented macular skin lesions, which occurred more commonly in black and mature infants and which were distinct clinically and histopathologically from erythema toxicum. Histopathology of skin biopsies of the vesicopustules is characterized by polymorphonuclear infiltration. The lesions often present as, or evolve into, a pigmented macule and persist from three weeks to three months. There are no associated systemic symptoms.

Metabolic rate and energy balance in infants with bronchopulmonary dysplasia

To determine energy use and growth of infants with bronchopulmonary dysplasia (BPD), we studied metabolic rate and energy balance in five infants with stage III-IV BPD (birth weight 1309 +/- 530 gm, gestational age 32 +/- 3 weeks, postnatal age 59.8 +/- 14.2 days) and in five control infants (birth weight 1540 +/- 213 gm, gestational age 33 +/- 2 weeks, postnatal age 42.0 +/- 4.2 days). Infants with BPD had significantly lower energy intake but higher energy expenditure than did control infants. Weight gain and energy cost of growth were significantly less in BPD infants than in control infants, as were urine output and output/intake ratio. We conclude that infants with BPD (1) absorbed caloric intake as well as did normal control infants, (2) had low energy intake and high energy expenditure, resulting in poor weight gain, and (3) had low energy cost of growth, suggesting an alteration in composition of tissue gain, with relatively high water content.