Recent advances in hyaline membrane disease.

Survival of infants with HMD has improved remarkably in the last decade. This has resulted from improved methods of diagnosis, which enables clinicians to recognize infection, the patent ductus, and the presence of pulmonary hypertension complicating HMD; from improved methods of ventilation, which result in a lower incidence of acute and chronic complications; and from a reduced incidence of pulmonary and extrapulmonary complications, such as bronchopulmonary dysplasia and retrolental fibroplasia. These advances arise from a deep understanding of pulmonary and metabolic physiology of the newborn infant with respiratory distress.

Tissue surface pH monitoring during reduced blood flow: Metabolic implications and sources of error.

To evaluate tissue surface pH as an indicator of the acid base status of arterial blood during periods of reduced blood flow, we examined the relationship between tissue surface pH, arterial pH, arterial lactic acid levels, and base deficit in fifteen spontaneously breathing anesthetized cats. Blood flow was reduced by hemorrhage to 50% of control blood pressure values (Fig. 3) or by infusing norepinephrine (10 mcg/kg/min intravenously) for one hour (Fig.

Oxygen consumption in apneic premature infants after low-dose theophylline.

The effects of 2 mg/kg/day theophylline (serum concentrations, 2.9 to 4.7 micrograms/ml) on metabolic rate were observed in 11 premature infants with severe idiopathic apnea of prematurity.

Infants of mothers treated with ethanol for premature labor.

Presented is a retrospective study of the newborn infants of mothers who were treated with ethanol in order to arrest premature labor, in comparison with matched control infants. In regard to neonatal mortality, there was no statistical difference between the study and the control infants. However, infants born within 12 hours after administration of ethanol had a significantly lower 1-minute Apgar score and a higher incidence of respiratory distress syndrome.

Assisted ventilation: a critical review.

Assisted ventilation is a complex technique that has been responsible for much of the improvement in neonatal morbidity and mortality during the last 10 to 15 years. In unskilled hands, however, it can be dangerous. Complications run as high as 30% in some series.

Flow-volume loops in newborn infants.

Flow-volume loops were obtained during the performance of crying vital capacity (CVC) maneuvers in 31 infants, 18 of whom had hyaline membrane disease (HMD). Both healthy and distressed infants had flow-volume loops resembling those found in adults with variable intrathoracic obstruction of the central airways. Flow rates during inspiration and expiration increased as the CVC increased.

[Pilot study into habitual abortion (author's transl)].

Endocrinic functional disorders obviously are more relevant than other factors to the aetiology of habitual abortion. Delayed menarche combined with menstrual disorders played a major role among the probands examined by the authors. Diagnosis of habitual abortion should be extended, with the view to elucidating other known causes of abortion for their importance to the situation under review.

Low-dose theophylline therapy in idiopathic apnea of prematurity.

The effects of theophylline at a dose of 2 mg/kg/day (with resultant serum concentrations of 2.8 to 3.9 micrograms/ml) were observed in seven premature infants with severe idiopathic apnea.

Baroreceptors in preterm infants: their relationship to maturity and disease.

Using passive tipping to a 45 degrees head-up position, an attempt was made to elicit reflex vasoconstriction in 13 non-distressed preterm infants and 27 infants with hyaline membrane disease, all between 26 and 38 weeks gestation. An increase in vascular tone associated with a significant reduction in peripheral blood-flow was found in 11 of the 13 non-distressed infants, while the same response was lacking in 23 of the 27 distressed infants. No infant demonstrated significant tachycardia with tilting, and the non-distressed infants failed to maintain their mean aortic blood-pressure during tilting.

Osteomyelitis in a neonatal intensive care unit.

Neonatal osteomyelitis presents with few clinical signs despite multiple sites of involvement. Four cases of osteomyelitis due to Staphylococcus aureus or Candida albicans were encountered in a neonatal intensive care unit. Three were unsuspected clinically and were detected as incidental radiologic findings.

Evaluation of methods of assisted ventilation in hyaline membrane disease.

Two methods of providing assisted ventilation were compared in infants severely ill with hyaline membrane disease (HMD). 10 infants were assigned to each group. One group received ventilation with a volume-cycled respirator, and the other was ventilated using a pressure-limited ventilator and reversed I:E ratio.

Alterations in state in apneic pre-term infants receiving theophylline.

The present study is a report on 9 premature infants treated with aminophylline for relief of apnea. With serum theophylline levels of 2 to 10 microgram/ml, all infants experienced significant decrease of apneic episodes in association with increased wakefulness and increased amounts of active (REM) sleep. These effects may occur independently, but it is possible that the alteration of sleep states may be partially responsible for the decrease in apneic episodes in these infants.

Noninvasive estimation of arterial oxygenation in newborn infants.

Two noninvasive methods of estimating arterial oxygenation were compared in a group of 48 infants ranging in birth weight from 870 to 4,000 gm, with diagnoses including apnea of prematurity, hyaline membrane disease, meconium aspiration, and congenital heart disease. Both transcutaneous oxygen measurements and ear oximetry gave reasonably accurate estimations of arterial oxygen levels within commonly used clinical ranges (PO2 50 to 70 mm Hg, arterial saturation 90 to 98%). Infants with shock demonstrated a wide range of values for transcutaneous oxygen levels, suggesting that this method has limited usefulness in this situation.

Serial determinations of oxygen profiles in infants with respiratory distress.

Serial oxygen profiles were determined for 20 newborn infants by measuring arterial tensions at low (20--40%), intermediate (60--80%), and high (95--100%) levels of inspired oxygen. These points were plotted on a graph which estimated the percentage of venous admixture at any particular level of inspired oxygen. The infants' oxygen profiles were then determined.

Pulmonary function following feeding in low-birth-weight infants.

Determination of functional residual capacity, arterial gas tensions and pH, and arterial-alveolar differences was carried out in a group of nondistressed premature infants to determine if significant alterations in lung volumes or ventilation perfusion relationships sufficiently large to cause cyanosis could be detected after feeding. The only statistically significant changes observed in these parameters were immediately following feeding, a fall of .01 pH units and a fall of 6 mm Hg in arterial oxygen tension; and 15 minutes after feeding, a fall of .

Sleep state, apnea and bradycardia in pre-term infants.

Respiratory pattern and heart rate were studied in 28 pre-term infants and four full-term infants during the first weeks of life. Sleep state was identified by standard neurological and EEG criteria. Apneic spells lasting 10 seconds or more were most frequent in the least mature infants, and their frequency tended to diminish with increasing maturity.