John M. Driscoll

Congenital failure of automatic control of ventilation, gastrointestinal motility and heart rate.

: A new congenital syndrome characterized by the simultaneous failure of control of ventilation (Ondines curse) and intestinal motility (Hirschsprungs disease) is reported in three infants, all of whom died in the first few months of life; two were siblings. Detailed studies in one also revealed markedly decreased esophageal motility and abnormal control of heart rate. In one infant, minute ventilation was lower in quiet than in REM sleep and lower in both states of sleep than in wakefulness. Although the mean inspiratory flow was decreased in quiet sleep, the hypoventilation resulted primarily from a decrease in respiratory frequency. Intravenous doxapram increased ventilation but did not reverse respiratory failure. Aminophyllin, progesterone, physostigmine and chlorpromazine did not change ventilation significantly; imipramine resulted in a significant decrease. Both long and short-term variability of the heart rate were markedly decreased when compared with the normal infant. Although neuropathologic studies postmorten did not reveal an anatomic defect, we postulate that a developmental abnormality in serotonergic neurons is responsible for this new syndrome.

Metabolic Acidosis Resulting from Intravenous Alimentation Mixtures Containing Synthetic Amino Acids

Abstract Hyperchloremic metabolic acidosis was observed in 11 infants receiving total parenteral nutrition containing mixtures of synthetic L-amino acids. The observed acidosis was not due to excessive gastrointestinal or renal losses of base as judged by the stool undetermined anion content and the urinary net acid excretion, nor was it due to infusion of preformed hydrogen ion as judged by the titratable acidity of the synthetic amino acid mixtures. Instead, the synthetic amino acid mixtures contain an excess of cationic amino acids in relation to anionic amino acids or other organic anions. Metabolism of these cationic amino acids results in a net excess of hydrogen ion, explaining the observed acidosis.

Hyperammonemia resulting from intravenous alimentation using a mixture of synthetic L-amino acids: A preliminary report

Hyperammonemia has been observed in three infants receiving total parenteral alimentation in which the nitrogen source was a mixture of synthetic L -amino acids (FreAmine). Two of the three infants developed lethargy, unresponsiveness, and twitching movements of the eyes and extremities followed by grand mal seizures. The hyperammonemia and associated clinical signs could be corrected by administration of 2 mmoles per kilogram of arginine-glutamate or 3 mmoles per kilogram of arginine-HCl and could be prevented by addition of as little as 0.5 to 1.0 mmoles per kilogram of arginine-HCl to the daily infusate. These observations make it mandatory to monitor blood ammonia levels in any infant receiving total parenteral alimentation.

Changing incidence of bronchopulmonary dysplasia

APART FROM RARE AND ISOLATED CASESOfpulmonary fibrosis occurring in very small infants, b ronchopu l monary dysplasia was first noted at the Babies Hospital , New York City, when artificial vent i la t ion for the treatmen t of respiratory distress syndrome was insti tuted. Over the past eight years, the incidence of BPD has fal len as techniques of neona ta l care have been improved and greater experience with artificial vent i la t ion has been gained. The lower incidence occurred despite an increase in survival rate and more frequent use of vent i la tory support on very small infants. We consider that the diagnosis of BPD canno t be m a d e without a history and wi thout a s tudy of sequent ia l films. With the changing techniques of assisted venti lat ion, we now rarely see the typical stages of the disease as described by Northway. In our lnsn tunon , we have seen two types of chronic lung disease in neonates : the first in the smallest in fant with little or no respiratory distress syndrome, and the second in infants surviving severe RD S (Table I). The changing survival rates according to weight group for the period 1972 to 1977 are presented in the Figure. The improved survival rate in very small infants has occurred concurrent ly with changes in bo th obstetr ic pracnce and newborn care. There have been more l iberal indicat ions for cesarean section for p remature b reech deliveries and for the very immatu re infant with fetal distress, as well as an earlier inst i tut ion of CPAP using nasal prongs and an increased use of mechan ica l venti lation for the very immatu re infant with respiratory difficulty. The changing incidence of BPD is presented in Table II. In 1970-1971. the condi t ion was seen in only four of 85 patients with RDS. two of whom were normal at seven months and two years, respectively; two died. A s t h m a and wheezing dur ing the first four years of life were seen in

Pulmonary follow-up of moderately low birth weight infants with and without respiratory distress syndrome*

Pulmonary function was measured in 18 children aged 6 to 9 years who had been born prematurely (mean birth weight 1760 +/- 555 g) and who had each received greater than 100 hours (mean 177 +/- 74 hours) of mechanical ventilation for respiratory distress syndrome (RDS). We used as controls 26 children aged 6 to 7 years who had been born prematurely (mean birth weight 1636 +/- 554 g) but who had required no treatment for pulmonary disease. Results for total lung capacity, FEV1, ratios of functional residual capacity and residual volume to total lung capacity, specific airway conductance, and alveolar plateau slope did not differ in the RDS and control groups. Eight of the 18 children in the RDS group had had radiologic evidence of bronchopulmonary dysplasia at 30 days and oxygen dependence at 30 days, but did not differ from the control group for any of the indices of pulmonary function. However, FEV1 and specific airway conductance were significantly reduced in the premature control group compared with children born at term. Therefore, factors associated with prematurity rather than combined effects of RDS and its treatment determined pulmonary function at age 6 to 9 years.

High incidence of lung perforation by chest tube in neonatal pneumothorax

Lung perforation by chest tube was noted to be a frequent complication of percutaneous pleural drainage in the newborn Infant with pneumothorax. Between 1972 and 1976, 12 such perforations were noted at autopsy. Of 209 consecutive patients admitted to the Neonatal ICU with clinical RDS, 28 (13.4%) developed a pneumothorax requiring pleural drainage and 21 of these died. Twenty were autopsied and a lung perforation directly related to the pleural drainage was found in seven. None of these lesions had been diagnosed clinically. If the survivors were assumed to be free of this complication, the incidence of lung perforation following pleural drainage was 25%. The true clinical incidence in our patients with RDS can only be equal to or higher than that number. Iatrogenic lung perforation is likely to contribute to the fatal course of the underlying disease or, in survivors, probably prolongs the period of recovery. The high incidence of this complication suggests a need to re-evaluate the technique of pleural drainage in the newborn infant with pneumothorax.

Total intravenous alimentation in low-birth-weight infants: A preliminary report

Nine infants with birth weights less than 1,200 Gm. received total intravenous alimentation for 5 to 24 days. In six infants, alimentation was started within 48 hours of birth; in three others, the procedure was started at 12 to 14 days of age. When a caloric intake of more than 100 Cal. per kilogram per day was achieved, weight gain averaged 15.3 Gm. per day and nitrogen balance averaged 0.23 Gm. per day. No significant deviations were observed of plasma sodium, potassium, calcium, phosphorus, and acid-base values. The time required to regain the initial body weight after institution of intravenous nutrition was significantly improved over that expected in conventionally managed infants of similar weights. The results demonstrate that the technique, when properly used, warrants further controlled investigation in premature infants.

Management of isoimmune neonatal thrombocytopenia

Two infants, who presented at birth with isoimmune thrombocytopenic purpura, are the basis for this report. The problems confronting the physician in treating an affected infant, as well as in the management of subsequent pregnancies after an infant with isoimmunization has been delivered, are discussed. In view of the small but serious risk of intracranial hemorrhage during the birth process in these infants, delivery by cesarean section is advocated for all pregnancies known to be at risk i.e., after a previous infant has been shown to be affected.

Effect of bacterial flora on staphylococcal colonisation of the newborn.

The umbilical and nasopharyngeal flora of newborn infants was examined on days 3, 14, and 42 of life. An analysis of the bacteriological findings suggests that colonisation by either Staphylococcus aureus or Staph. epidermidis prevents colonisation by the other staphylococcus. Similarly, colonisation by Gram-negative bacteria prevents colonisation by staphylococci. Further, this bacterial interference lasts for as long as 42 days, which suggests the possibility of artificially colonising newborns with nonpathogens to prevent subsequent colonisation and disease by virulent microorganisms.

Current Concepts in Neonatal Bacterial Colonization

Bacterial infections are a major cause of neonatal morbidity and mortality. Unfortunately, the impact of anitmicrobial therapy on the natural historyo of bacterial infections in the newborn has been lee dramatic than the effect of these agents on the natural history of bacterial infections in the older child and adult. There is a long tradition of perinatal preventive measures designed to decrease the frequency of such infections. Since most of the bacterial pathogens reponsible for neonatal infecttions are part of the normal flora that routinely colonize the newborn, many of the recently developed preventive measures involve the controlled manipulation of bacterial colonozation. What follows is a discussion of current concpets of neonatal bacterial colonozation and some of the preventive measures recently introduced into nurseries.