Bernard H. Feldman

Absence of Phosphatidylglycerol (PG) in Respiratory Distress Syndrome in the Newborn

Summary: Phosphatidylglycerol (PG) was absent from lung effluent in 41 infants with respiratory distress syndrome of the newborn (RDS), whereas effluent from healthy control subjects of similar gestational age contained this phospholipid (4.9 ± 2.4% of lipid-phosphorus (P), n = 32). Control infants of 28 weeks of gestation or less with various respiratory disturbances other than RDS also had low PG (0.2 ± 0.2% of lipid-P, n = 5). In RDS surfactant complex often could be isolated from the airways using differential and density gradient centrifugation. The material thus obtained had prominent phosphatidylinositol (PI) (13.6 ± 2.8% of lipid-P, n = 6), but no PG. Of those 18 infants who had such surfactant even in the early stages of RDS, 13 were 35 weeks of gestation or more, 3 were offspring of diabetic mothers, and 2 had severe perinatal asphyxia. In healthy control subjects PG sometimes appeared first within an hour of birth, but in RDS PG did not appear until recovery from RDS.In RDS type II (transient tachypnea of the newborn) PG in lung effluent also was abnormally low (1.3 ± 0.6% of lipid-P, n = 5) and PI was correspondingly prominent (9.7 ± 3.6% of lipid-P, n = 5), indicating immaturity of surfactant similar to RDS.Surfactant with PG and PI has superior surface-active properties compared to that containing PI, but no PG. Surfactant without PG does not seem to stabilize the alveoli of the newborn as well as does surfactant with PG. The failure of PG appearance following birth therefore may precipitate RDS, especially beyond 35 weeks of gestation.Speculation: Pre- and postnatal monitoring of the acidic phospholipids, PG and PI, in lung effluent is useful in diagnosis and follow-up of RDS as well as in evaluation of various therapies.

Closure of the patent ductus arteriosus with ligation and indomethacin: a consecutive experience.

This report summarizes a consecutive experience with 59 preterm infants with clinical, radiographic, and echocardiographic findings of a large patent ductus arteriosus. Thirty-five infants who met defined criteria received indomethacin, and 24 infants underwent PDA ligation. Analysis of the clinical course of these infants revealed no selective indomethacin morbidity and suggests that infants undergoing ligation require more prolonged ventilator therapy with increased exposure to FiO2 greater than or equal to 0.3. Mortality rates between ligated and pharmacologically treated groups were similar. This study documents that inhibition of prostaglandin synthesis to constrict and close the PDA in the premature infant is an effective alternative to operative closure.

Absence of phosphatidylglycerol (PG) in respiratory distress syndrome in the newborn. Study of the minor surfactant phospholipids in newborns.

Summary: Phosphatidylglycerol (PG) was absent from lung effluent in 41 infants with respiratory distress syndrome of the newborn (RDS), whereas effluent from healthy control subjects of similar gestational age contained this phospholipid (4.9 ± 2.4% of lipid-phosphorus (P), n = 32). Control infants of 28 weeks of gestation or less with various respiratory disturbances other than RDS also had low PG (0.2 ± 0.2% of lipid-P, n = 5). In RDS surfactant complex often could be isolated from the airways using differential and density gradient centrifugation. The material thus obtained had prominent phosphatidylinositol (PI) (13.6 ± 2.8% of lipid-P, n = 6), but no PG. Of those 18 infants who had such surfactant even in the early stages of RDS, 13 were 35 weeks of gestation or more, 3 were offspring of diabetic mothers, and 2 had severe perinatal asphyxia. In healthy control subjects PG sometimes appeared first within an hour of birth, but in RDS PG did not appear until recovery from RDS.In RDS type II (transient tachypnea of the newborn) PG in lung effluent also was abnormally low (1.3 ± 0.6% of lipid-P, n = 5) and PI was correspondingly prominent (9.7 ± 3.6% of lipid-P, n = 5), indicating immaturity of surfactant similar to RDS.Surfactant with PG and PI has superior surface-active properties compared to that containing PI, but no PG. Surfactant without PG does not seem to stabilize the alveoli of the newborn as well as does surfactant with PG. The failure of PG appearance following birth therefore may precipitate RDS, especially beyond 35 weeks of gestation.Speculation: Pre- and postnatal monitoring of the acidic phospholipids, PG and PI, in lung effluent is useful in diagnosis and follow-up of RDS as well as in evaluation of various therapies.

1757 NO CARDIAC ARRHYTHMIAS WITH COMBINED BRONCHODILATOR THERAPY IN CHILDREN WITH ASTHMA

Theophylline (T) and beta adrenergic agonists are commonly used in combination therapy for the control of asthma. Previous animal studies have suggested that this may result in the induction of significant cardiac arrhythmias (CA). This study examined the effects of combined bronchodilator therapy in 7 children with chronic asthma (ages 9–14 years) and used 24 hour Holter monitoring (HM) to document the drug effects on cardiac rhythm. Three drug regimens were administered in random order for 24 hour periods:sustained release (SR) T alone; inhaled albuterol (A) alone; and combined SR T plus A. HM was carried out during each 24 hour drug period. During T alone and T plus A, mean trough T levels were 12.8±3.1 and 13.4±3.3 ug/ml (M±SD). For A alone, T had been withheld for 24 hours, with trough T level of 1.6±.1.7. Sequential pulmonary function testing performed for 8 hours for each drug regimen showed comparable improvement of FEV1, PEFR and FEF25–75 above baseline levels. Peak heart rate during a dosing interval was increased to a comparable degree by all treatment regimens: T=18.9±17.5 beats/min; A=12±7.6; T plus A=18.3±11.5. Only 1/7 patients had ventricular ectopy, uniform single ventricular premature depolarizations (VPD), with the mean hourly frequency identical for all treatment regimens (2.4±2.6 VPD/hour). We conclude that the combination of SR T plus A does not significantly increase heart rate more than T or A alone and does not induce significant CA.

Absence of Phosphatidylglycerol |[lpar]|PG|[rpar]| in Respiratory Distress Syndrome in the Newborn

Summary: Phosphatidylglycerol (PG) was absent from lung effluent in 41 infants with respiratory distress syndrome of the newborn (RDS), whereas effluent from healthy control subjects of similar gestational age contained this phospholipid (4.9 ± 2.4% of lipid-phosphorus (P), n = 32). Control infants of 28 weeks of gestation or less with various respiratory disturbances other than RDS also had low PG (0.2 ± 0.2% of lipid-P, n = 5). In RDS surfactant complex often could be isolated from the airways using differential and density gradient centrifugation. The material thus obtained had prominent phosphatidylinositol (PI) (13.6 ± 2.8% of lipid-P, n = 6), but no PG. Of those 18 infants who had such surfactant even in the early stages of RDS, 13 were 35 weeks of gestation or more, 3 were offspring of diabetic mothers, and 2 had severe perinatal asphyxia. In healthy control subjects PG sometimes appeared first within an hour of birth, but in RDS PG did not appear until recovery from RDS.In RDS type II (transient tachypnea of the newborn) PG in lung effluent also was abnormally low (1.3 ± 0.6% of lipid-P, n = 5) and PI was correspondingly prominent (9.7 ± 3.6% of lipid-P, n = 5), indicating immaturity of surfactant similar to RDS.Surfactant with PG and PI has superior surface-active properties compared to that containing PI, but no PG. Surfactant without PG does not seem to stabilize the alveoli of the newborn as well as does surfactant with PG. The failure of PG appearance following birth therefore may precipitate RDS, especially beyond 35 weeks of gestation.Speculation: Pre- and postnatal monitoring of the acidic phospholipids, PG and PI, in lung effluent is useful in diagnosis and follow-up of RDS as well as in evaluation of various therapies.

Neonatal Intensive Care in Community Hospitals and Remote Areas: The Problems and a Possible Solution

This has been a brief summary of the problems emerging as more community hospitals develop neonatal intensive care, analyzing their possible origins and significance. A description of one solution to the problem has been given, exemplified by an outreach program from the University of California, San Diego, and University Hospital, San Diego, with the community of Las Vegas, Nevada. We feel strongly that the responsibilities of medical schools toward community hospitals and toward regionalization in isolated communities should be unique and are not covered by usual regulations or traditional concepts of regionalization.