The effect of restricted fluid intakes in the first week of life on the risk of bronchopulmonary dysplasia and patent ductus arteriosus in very low birth weight infants / 소아과

PURPOSE: We investigated the effects of restricted fluid in the first 7 days of life on the risk of bronchopulmonary dysplasia (BPD) or patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants. METHODS: Eighty three VLBW infants who lived more than 28 days were selected. The amount of daily maintenance fluid was determined by calculation of insensible water loss (IWL) and urine output (UO). Seventy to 80 percent of calculated amount was given to the ventilated infants. Subjects were grouped into low (75th%) fluid groups for the first 24 hours, 3 days and 7 days. Chi square tests analyzed proportions of subjects with or without morbidities across fluid groups. Multivariate logistic regression was used to analyze the effect of fluid intake on BPD or PDA, controlling for factors that are significantly associated with BPD or PDA by univariate analysis. RESULTS: Rates of BPD and PDA were not significantly associated with fluid groups on each time period. The result was the same after controlling for factors that are significantly associated with BPD or PDA by univariate analysis. For the first 3 and 7 days, fluid intakes were positively related with maximal weight loss, urine output and mechanical ventilation duration. CONCLUSION: In VLBW infants, when given based on needs reflected from IWL and UO versus intake, relatively low fluid intakes in the first week of life do not decrease the risk of BPD or PDA, and vice versa. We suggest that calculation of daily fluid based on IWL and UO is appropriate for VLBW infants.

Early Prediction of Bronchopulmonary Dysplasia in Very Low Birth Weight Infants with Mechanical Ventilation in the First Week of Life

PURPOSE: Multifactorial in pathogenesis, bronchopulmonary dysplasia is difficult to predict based on any single factor, especially early in life. We evaluated clinical and ventilatory parameters in the first week of life, and their combinations were tested for early prediction of BPD. METHODS: Eighty-one very low birth weight (VLBW) infants born at gestational ages or =4.5 on day 7 (OR 3.982, 95% CI 1.046-15.162) and maximum FiO2> or =0.3 on day 7 (OR 7.626, 95% CI 1.570-37.054). The combination of these factors for prediction of BPD had a 79% positive predictive value with an 85% sensitivity. CONCLUSION: A number of clinical and ventilatory parameters in combination (gestation, maximum MAP and FiO2 on day 7) can predict BPD in VLBW infants early in life with a relatively high sensitivity and positive predictiveness. With early identification of infants prone to BPD, the clinicians may resort to more active measures to minimize lung injury and to prevent BPD.

Ultrasonographic Bladder Parameters for Successful Suprapubic Bladder Aspiration / 소아과

PURPOSE: Suprapubic bladder aspiration(SBA) is a widely accepted method of obtaining sterile urine for culture in neonates but has a relatively low success rate and a few serious complications during SBA procedure. To improve the chance of obtaining urine, we determined the ultrasonographic bladder parameters(diameters and volume) to confirm that the bladder is adequately distended for successful aspiration of urine. METHODS: In 94 newborn infants who required sterile collection of urine, ultrasonographic examination and SBA procedure were carried out. On the patient's suprapubic area, the maximal cephalocaudal and anteroposterior diameters were measured by sagittal scanning, and the maximal anteroposterior and transverse diameters by transverse scanning. Bladder volume was calculated using the formula for elliptic volume, and then urine was aspirated to maximum of 10 mL and the amount of urine aspirated was recorded. RESULTS: Sufficient urine for culture(>1 mL) was obtained by SBA in 86(91.5%) of 94 infants. In the sagittal view, when the cephalocaudal diameter of the bladder was greater than 20 mm and the anteroposterior diameter was greater than 15 mm, the success rate was 100%. The cephalocaudal diameter of the bladder in sagittal view showed a more significant positive correlation with aspirated urine amount(r=0.65, P<0.001). CONCLUSION: The ultrasonographic sagittal view improved the success rate of SBA in neonates. A SBA was more likely to be successful when the cephalocaudal diameter of the bladder was above 20 mm and the anteroposterior diameter was above 15 mm.

The Role of Aldosterone on the Development of Renal Tubular Reabsorption in Low Birth Weight Infants

PURPOSE: To determine the postnatal changes in aldosterone action on the renal tubular reabsorption in low birth weight(LBW) infants, we assessed the relation of the aldosterone concentrations to renal parameters during the first 10 days of life. METHODS: Twenty LBW infants were evaluated and their gestational ages ranged from 32.4 to 39.3 weeks and their birth weights ranged from 1,440 to 2,500 g. Estimated glomerular filtration rate, fractional excretion of sodium(FENa) and potassium(FEK), and plasma aldosterone concentrations were analyzed according to the postnatal age and the conceptional age(CA). RESULTS: Glomerular functions were improved after birth and were correlated with CA. FENa and FEK decreased after birth and correlated with CA. Plasma aldosterone concentrations increased to 318.6 +/- 147.2 ng/dL at 48 hours and then decreased to 162.0 +/- 72.2 ng/dL at 10 days after birth. Plasma aldosterone concentrations of infants less than 38th week of CA were higher than that of infants more than 38th week. There was a significant negative correlation coefficient between plasma aldosterone concentrations and FENa in infants more than 34th week of CA, but not in that of less than 34th week. CONCLUSIONS: LBW infants have higher plasma aldosterone concentrations, but a poor correlation between plasma aldosterone concentration and urinary sodium excretion for the first few days of life and in lower chronologic aged infants. These results show that the renal tubule reabsorption of sodium is less responsive to plasma aldosterone in these infants and, therefore, the careful management of fluid and electrolyte balance is mandatory.