Main stem bronchial occlusion in a neonate.

In recent years it has become evident that partial obstruction of bronchi can be acquired postnatally secondary to mechanical trauma caused during prolonged endotracheal intubation. In the presented case, a complete obstruction of the right main stem bronchus developed during the neonatal period despite a relatively short time of intubation. The etiological background is discussed.

Plasma ascorbic acid levels in premature infants.

During gestation the fetus is abundantly provided with vitamin C, but inadequate postnatal provision of the vitamin may lead to early hypoascorbemia. Since premature newborns are often prevented from full alimentation for a considerable length of time, ascorbate deficiency may result. Plasma ascorbate levels of 20 premature newborns were determined during the first two weeks of life. Daily ascorbate intake of less than 5 mg/kg b. w. resulted in a decline of plasma ascorbate level from 1.56 +/- 0.15 mg/100 ml (mean +/- SEM) on the first day of life to a low level of 0.48 +/- 0.05 mg/100 ml by two weeks of age. An increase of daily ascorbate intake to 5--10 mg/kg b.w. resulted in a higher plasma concentration of 0.79 +/- 0.09 mg/100 ml (p less than 0.02) while parenteral supplementation of 50 mg vitamin C daily provided for a high plasma concentration of 2.7 +/- 0.46 mg/100 ml (p less than 0.005) when compared with the other two groups. Maturational and environmental factors may impose a higher demand for vitamin C during early premature life and therefore adequate amounts of the vitamin should be early provided.

Vitamin E and vitamin C plasma levels in premature infants following supplementation of vitamin C.

Our preliminary data suggest that supplementation of premature neonates with vitamin C is required to maintain adequate ascorbate plasma levels and may have a sparing effect on vitamin E metabolism. Further studies are required to validate our findings and evaluate the possible antioxidant advantage of ascorbic acid administration.

Plasma creatinine in neonates with atresia of the upper gastrointestinal tract.

The human fetus swallows a considerable amount of amniotic fluid which appears to be in balance with the urine output. Since amniotic fluid intake is considered to be compromised in fetuses with atresia of the upper gastrointestinal tract, glomerular function development in such infants may be delayed. Plasma creatinine level determined in 6 neonates with atresia of the upper gastrointestinal tract was similar to the level measured in neonates with lower obstruction, and both groups were within the range of values obtained during other studies in normal newborns. Glomerular functional development is probably not affected in neonates with atresia of the upper gastrointestinal tract.

High plasma ascorbic acid levels in premature neonates with intraventricular hemorrhage.

The accumulation of ascorbic acid in the brain by active transport establishes a high brain-plasma gradient of the vitamin. An insult to the CNS may result in an efflux of ascorbate into the circulation with a consequent rise of plasma levels. We measured plasma ascorbic acid levels in premature neonates on days 1, 3, and 5 of life, and the infants underwent ultrasonographic examination to detect intracranial hemorrhage. Neonates with intraventricular hemorrhage sustained significantly higher plasma ascorbate levels than their controls. Infants with massive bleeding had higher levels than those with a smaller hemorrhage. These results suggest that an efflux of ascorbic acid into the circulation occurs secondary to intracranial hemorrhage.

Effect of skinfold thickness on transcutaneous bilirubin measurements.

We studied the effect of skinfold thickness on the correlation between serum total bilirubin level and transcutaneous bilirubin (TcB) readings. Skinfold thickness measurements were taken at 1-4 h of age. Serum total bilirubin levels and TcB readings were obtained at 1-4 (first) and 44-56 h of age (discharge). No correlation was found between first reading and skinfold thickness (rho = -0.196), whereas correlations with first serum bilirubin level and blood hematocrit were 0.397 and -0.373, respectively. The correlation between discharge serum total bilirubin level and TcB reading was affected by skinfold thickness, and not improved with the use of first reading as a reference for discharge reading.

Standards of skinfold thickness and anthropometric indices in term Israeli newborn infants.

Anthropometric measurements including weight, length, head and mid-arm circumferences, skinfold thickness (biceps, triceps, subscapular, abdominal, suprailiac and quadriceps) were obtained from 250 singleton, full-term infants within 4 h of birth. Anthropometric indices for total body fat stores such as arm fat and nonfat areas, adiposity and ponderal indices, and weight/length ratio were calculated. These data may be helpful in determining nutritional status at birth and assessing postnatal growth of Israeli infants.

Intravenous immunoglobulin for Flavobacterium-induced thrombocytopenia in a premature infant.

Gram-negative septicemia at times causes morbidity and mortality in newborn nurseries. Prophylactic intravenous immunoglobulin results in a significant decrease in incidence and severity of septicemia resulting from infection in infants. The present case report describes the successful use of high-dose intravenous immunoglobulin in a Flavobacterium-induced thrombocytopenia in a premature infant.

The mean platelet volume (MPV) in the neonatal period.

Previous studies in adults have demonstrated that the mean platelet volume (MPV), which is now routinely measured during blood counting performed by the Coulter Counter S Plus, is an important parameter and may serve as a predictor of the hemostatic potential of patients with severe thrombocytopenia. MPVs and platelet counts were determined in 155 neonates in order to establish the normal values of the mean platelet volume during the neonatal period. Analysis of variance performed in 119 neonates of birthweight greater than 2 kg revealed a significant rise with age of both platelet count (P less than 0.0001 and MPV (P less than 0.02) during the neonatal period. The platelet counts of these 119 neonates (323336 +/- 106918; mean +/- SD) were significantly higher (P less than 0.05) than the platelet counts (283805 +/- 114130) of 36 neonates where birthweight was less than 2 kg. There was no significant difference between the MPV values of the two groups (8.67 +/- 1.03 micron3 and 8.89 +/- 1.10 micron3, respectively). Since increased MPV is observed during periods of platelet production, the above results suggest that the rise of platelet count associated with increased MPV in newborn infants is due to increased production of platelets in the early postnatal weeks.

High-frequency positive-pressure ventilation in neonates.

Twenty-five newborn infants with severe respiratory failure responding poorly to conventional mechanical ventilation were switched to high-frequency positive-pressure ventilation (HFPPV) at 90 to 180 cycle/min (mean 158), an estimated tidal volume less than or equal to 3 ml/kg body weight, an inspiratory time of 0.1 sec, and a PEEP of 3 to 17 cm H2O. In all infants, HFPPV increased PaO2 (mean 66 torr) and decreased PaCO2 (mean 14 torr) within 1 h. Fourteen hours after onset of treatment, the FIO2 requirement had decreased from 1.0 to 0.6 in all infants. Mean airway pressure (Paw) with HFPPV was usually less than or equal to Paw during conventional ventilation. In spite of the often high level of PEEP used, pneumothorax occurred in only 2 infants and bronchopulmonary dysplasia in 1. Eighteen (72%) infants survived and none died of respiratory failure. The use of HFPPV might be beneficial in neonates with severe respiratory failure that responds poorly to conventional therapy.

Hydroperoxide-induced chemiluminescence of the perfused lung.

Light-emission of the perfused lung is induced by t-butyl hydroperoxide, giving chemiluminescence yields that oscillate between 800 and 1500 counts/s depending on the site and position of the lung. The response of the perfused lung to infusion with different hydroperoxides gives a pattern similar to that observed with the liver microsomal fraction; ethyl hydroperoxide shows a much higher chemiluminescence yield than the tertiary (t-butyl and cumene)hydroperoxides. Alveolar oedema affected the light-emission of the perfused lung depending on the time at which oedema developed, decreasing light emission on infusion of hydroperoxide in the oedematous lung and increasing it when oedema appeared after the maximal chemiluminescence yield was already achieved. Paraquat, administered in vivo, augmented light-emission by approximately 2-fold. The effect of paraquat was a time-dependent process. Lung chemiluminescence, compared with liver chemiluminescence, needed higher hydroperoxide concentration to induce light-emission.