Robert S. Roth

Risk factor analysis of intraventricular hemorrhagein low-birth-weight infants

Sixty of 63 newborn infants weighing less than 1,250 gm, admitted consecutively to the Intensive CareNursery during a 15-month period, were prospectively investigated for the incidence of intraventricular hemorrhage by early computerized tomography, or by autopsy. Nineteen of the 60 infants had evidence of IVH. The incidence of IVH was correlated with the presence of possible neonatal, obstetrical, asphyxial, or therapeutic risk factors. There was a significant difference in only one of the risk factors: birth outside the perinatal center. Fifteen of 27 outborn infants (56%) developed IVH, whereas only four of 33 inborn infants (12%) developed IVH ( P P P P P

1432 TREATMENT OF NEONATAL CHRONIC LUNG DISEASE WITH FUROSEMIDE

Long term furosemide therapy has been recommended for neonatal chronic lung disease. 28 preterm infants (986±60 gm) with stable or worsening chronic lung disease due to bronchopulmonary dysplasia or chronic pulmonary insufficiency of the premature were treated with 1-2 mg/kg q 6 hours of furosemide. Infants entered this prospective study if they required mechanical ventilation for >2 wks or for FiO2 of>.4,>.3 or >.21 at 3, 4 or 6 wks of age, respectively. Infants were evaluated using a computerized score based on peak ventilator pressures, end expiratory pressures, ventilator rate, FiO2 and PaCO2. Each infant acted as his own control. If he responded initially, therapy was discontinued after 7 days and he was evaluated for deterioration. 20/28 infants showed significant improvement (p<.010) when treated with furosemide. There were no significant differences between responders (n=20) and nonresponders (n=8) in mean gestational age (28.2 vs 28.5 wks), birth weight, male-female distribution, age at start of study, or type of chronic lung disease. 12/20 responders had a significant deterioration in their respiratory scores when therapy was discontinued. 21/28 received a second trial of furosemide: 14/21 responded to retreatment. An infants response in the second trial was independent of his response in the first trial. Brief periods of furosemide therapy may be useful in the management of chronic lung disease in some preterm infants, but prolonged continuous use needs further evaluation.

1486 FOLLOW-UP OF HYPERVENTILATED NEONATES

Hyperventilation has been advocated for treatment of newborn infants with pulmonary hypertension; however, there are theoretical harmful effects of hyperventilation on the immature nervous system. From March 1977 to May 1979, 13 infants > 37 weeks gestation were selected to be hyperventilated because of severe hypoxemia refractory to conventional mechanical ventilation, i.e., failure to maintain PaO2 > 50 torr with an FiO2 1.0, despite PaCO2 <40 and pH >7.40. Eleven survived, 9 were available for follow-up evaluation. Seven infants had meconium aspiration syndrome, one had HMD, one had Gp B strep sepsis. All infants eventually required a decrease in PaCO2 to <20 torr and increase, in pH to >7.50 before a change in AaDO2 became evident. As a group, the 9 infants were exposed to a PaCO2<20 torr for 51.8±11.8 hrs (mean±SEM), to PaCO2 <15 torr for 11.8±3.3 hrs, to a pH 7.50 for 64.4±18.6 hrs, and to a pH>7.60 for 6.1±2.9 hrs. One infant was lost to follow-up after a normal assessment at 9 mos. The other 8 infants (7 AGA, 1 markedly SGA) were at least 1¼ years at the time of evaluation. The 7 AGA infants had a normal developmental quotient (mean±110, range 96-130) by Stanford Binet or Bayley; the one SGA infant had a Bayley of 89. All 8 had normal neurological examinations. All AGA infants are growing normally. Although only 9 infants with short term follow-up are reported here, these preliminary oservations are reassuring with respect to neurological and developmental outcome following prolonged hyperventilation.

Risk Factor Analysis of Intraventricular Hemorrhage in Low-Birth-Weight Infants

Sixty of 63 newborn infants weighing less than 1,250 gm, admitted consecutively to the Intensive Care Nursery during a 15-month period, were prospectively investigated for the incidence of intraventricular hemorrhage by early computerized tomography or by autopsy. Nineteen of the 60 infants had evidence of IVH. The incidence of IVH was correlated with the presence of possible neonatal, obstetrical, asphyxial, or therapeutic risk factors. There was a significant difference in only one of the risk factors: birth outside the perinatal center. Fifteen of 27 outborn infants (56%) developed IVH, whereas only four of 33 inborn infants (12%) developed IVH (P less than 0.001). There were no statistically significant differences in maternal obstetrical risk factors, infant risk factors, or indices of birth asphyxia in the inborn compared with the outborn infants. However, perinatal therapeutic risk factors differed between the two groups. Outborn infants were less likely to have received betamethasone (P less than 0.001), were less likely to have their arterial blood gases monitored and stabilized during the first 20 minutes after birth (P less than 0.001), and were given more bicarbonate (P less than 0.001) and more boluses of fluid intravenously (P less than 0.02). The risk of IVH in very low birth-weight infants may be significantly decreased by therapeutic factors at birth. Maternal transport to a perinatal center and intensive neonatal resuscitation may contribute to decreasing the incidence of intraventricular hemorrhage.

1404 FACTORS INFLUENCING INCIDENCE OF RETROLENTAL FIBROPLASIA

Retrolental fibroplasia (RLF) remains a significant problem in premature low-birth-weight infants. Since 1976, all infants in our intensive care nursery < 1500 gm have had routine eye examinations from the time they were stable enough to be examined until at least 1 month following discharge. Since 1978, all infants <1500 gm who required supplemental oxygen or ventilation had frequent transcutaneous oxygen monitoring along with intermittent PaO2 measurements. The incidence of RLF in infants <1500 gm was 7% from 1976-1978 and 10% from 1978-present but mean birthweight in the later group was significantly lower (1087 gm vs 1166 gm p<.001). Since 1978, 16/160 infants <1500 gm developed RLF: 7 had bilateral Stage I, 5 progressed to bilateral Stage II, 3 had bilateral Stage II-III and 1 had bilateral Stage V with complete blindness. Infants with RLF did not differ significantly in sex distribution, incidence of hyaline membrane disease, patent ductus arteriosus or treatment with betamethasone from infants without RLF. The incidence of chronic lung disease, which was divided equally between bronchopulmonary dysplasia and chronic pulmonary insufficiency of the premature, was significantly higher in infants with RLF (87% vs 26%, p <.001) and birthweight was significantly lower (1017 gm vs 1096 gm, p<.001). Transcutaneous oxygen monitoring has not prevented RLF in low-birth-weight infants requiring long term oxygen supplementation.

1234 FOLLOW-UP OF PRETERM INFANTS AFTER PRENATAL BETAMETHASONE (BETA)

Prenatal Beta to prevent Hyaline Membrane Disease has been used at Mt. Zion Hospital since July 1972. Serial assessments of neurological and developmental status of 128 infants weighing <1250 gm were done at 1-6 years of age (mean age 30.7 months). Mental development was considered normal(N), borderline(B) or abnormal(A) if developmental or intellectual quotients were >80,70-80 and<70 respectively. Motor development was considered B if there was clumsiness or mild paresis and A if moderate to severe cerebral palsy. The table presents outcome for inborn(IB) and outborn(OB) infants whose mothers received ≥1 dose (Rx) of Betamethasone vs untreated (unRx) infants.Rx infants showed no deficits in growth (weight, height or head circumference) when compared with unRx infants. Rx infants also compared favorably in mental and motor development and there were significantly more normal infants in the Rx group (83% vs 63.5%), p < 0.025.