Follow-up of school-age children with bronchopulmonary dysplasia.

OBJECTIVE: To investigate the outcome of school-age children with bronchopulmonary dysplasia (BPD) in terms of nutrition, pulmonary function, and intelligence, and to compare the results with a preterm cohort matched for gestational age and birth weight, and with a term control group. DESIGN: Cross-sectional. SETTING: Follow-up clinic at level III neonatal intensive care unit, university-affiliated hospital, Children's Hospital. SUBJECTS: Twelve children who had BPD as infants and 2 control groups of 12 children each. MAIN OUTCOME VARIABLES: Anthropometric measurements, dietary intake, resting energy expenditure, pulmonary function, body composition measurements by dual energy x-ray absorptiometry, and Weschler intelligence test scores. RESULTS: Children with BPD had decreased forced expiratory volume at 1 second, decreased forced expiratory flow between 25% and 75% of vital capacity, and decreased maximal expiratory flow velocity at 50% of vital capacity compared with age-matched normal inborn subjects (p = 0.025, p = 0.005, and p = 0.0013, respectively). Both children with BPD and matched preterm control children were shorter than infants in the term control group (p = 0.018). There were no significant differences in the other anthropometric parameters studied. The groups did not differ in resting energy expenditure. Lean body mass was lower in the BPD group compared with the term control groups (p = 0.017). Bone mineral content was lower in the BPD group compared with both the preterm and term control infants (p = 0.050 and p = 0.059, respectively). The mean performance intelligence quotient (IQ) and full-scale IQ scores in the BPD group were lower than in the term control group (p = 0.011 and p = 0.029, respectively). The proportion of children with borderline or intellectually deficient scores was significantly higher in the preterm group compared with the term group for verbal, performance, and full-scale IQ scales (p = 0.046, p = 0.018, and p = 0.048 respectively). The proportion of children with BPD who had borderline or deficient performance IQ scores was higher than for the term group (p = 0.046). CONCLUSIONS: The lower height and intelligence scores in children with BPD may be related to prematurity and perinatal events rather than pulmonary disease. Subclinical pulmonary dysfunction in children with BPD persists at school age. The lower amount of lean body mass and possible decrease in bone mineral content in children with BPD may be related to their smaller size.

Pharmacokinetics and nephrotoxicity of continuous intravenous infusion of gentamicin in low birth weight infants.

We evaluated the pharmacokinetics and renal effects of continuous intravenous infusion of gentamicin compared with multiple-dose therapy given in equivalent daily amounts. Nine infants (mean gestational age 34.7 weeks, mean birth weight 2107 gm) were given intermittent injections of gentamicin and 10 infants (mean gestational age 34.8 weeks, mean birth weight 2078 gm) received gentamicin by continuous infusion. Comparison of gentamicin pharmacokinetic data revealed a larger volume of distribution and AUC, prolonged terminal t1/2, and slower total body clearance of the drug in those infants receiving gentamicin by continuous infusion. During and after therapy the fractional excretion of sodium was significantly increased in the continuous infusion group. After treatment the creatinine clearance and excretion of beta 2-microglobulin were significantly lower in the continuous therapy group. Our results indicate that infants receiving gentamicin by constant infusion are at higher risk of nephrotoxicity. The extent of this nephrotoxic hazard remains to be determined.

Pharmacokinetics of paraldehyde disposition in the neonate.

The pharmacokinetic parameters controlling paraldehyde elimination were determined in nine infants infused with paraldehyde at the rate of 150 mg/kg/hr in a 5% solution in 5% dextrose for the treatment of status epilepticus. The mean +/- SEM values for the observed parameters were as follows: rate constant for the disposition of paraldehyde 0.0680 +/- 0.0071 hr,-1 half-life 10.2 +/- 1.0 hr; volume of distribution 1.73 +/- 0.20 L/kg; clearance 0.121 +/- 0.023 L/hr/kg. Phenobarbital administration prior to or within 24 hours of the cessation of paraldehyde infusion decreased both paraldehyde clearance and volume of distribution in a manner linearly related to the logarithm of the phenobarbital dose. The rate constant for paraldehyde elimination was decreased as a linear function of the logarithm of the combined dose of administered phenobarbital and phenytoin. No acetaldehyde was detected in any blood samples. Paraldehyde administration was not correlated with any adverse reactions or toxicities.

Respiratory infections in infants on mechanical ventilation: the immune response as a diagnostic aid.

A prospective study was undertaken in 41 newborn infants receiving artificial respiration for evaluation of the incidence of respiratory infections. Clinical and radiologic evidence of pneumonia was compared with the appearance of serum antibodies against antigens prepared from microorganisms isolated from bronchial aspirates, and with serum and bronchial immunoglobulin M values. A significant specific immune response was documented in 24% of the patients studied. The data indicate that by correlating the clinical and radiographic findings with specific antibodies and IgM antibody responses, it is possible to document a significant number of respiratory infections. One implication of this study is that subclinical infections may not be uncommon. The significance of the presence and changes in concentration of IgM in bronchial aspirate requires further study.

Group B beta hemolytic streptococcal sepsis and the idiopathic respiratory distress syndrome: a comparison.

The clinical features of 27 patients with early onset group B beta hemolytic streptococcus sepsis were reviewed. Fifteen presented with a clinical pattern indistinguishable from the idiopathic respiratory distress syndrome and were compared with 15 patients with IRDS. Rupture of membranes for greater than 12 hours prior to delivery occurred more often in patients with GBS (33%) than in the patients with IRDS (16%). Hypotension was more commonly seen in the patients with GBS (56%) than in the patients with IRDS (36%). There was no difference in the incidence of apnea or the respirator peak inspiratory pressure requirements between the two groups of patients, but there was a tendency for a decline in the total white blood cell count in the first 24 hours of life in those patients with GBS sepsis.

Paradoxical behavior of serum digoxin concentrations in an anuric neonate.

Serum digoxin values were determined in a newborn infant with severe heart failure and renal failure. The half-life of digoxin in the serum appeared to change, possibly the result of prolonged distribution and/or absorption owing to circulatory insufficiency, or to the accumulation of cross-reacting metabolites of digoxin in the serum. No clinical toxicity was apparent, and no cardiac arrhythmia was observed. The need for monitoring serum digoxin concentration and clinical effect in newborn infants is emphasized.