Frank M. Shepard

Residual Pulmonary Findings in Clinical Hyaline-Membrane Disease

Abstract Seventy infants who had clinical hyaline-membrane disease as neonates were followed from two to five years with repeated physical examinations and x-ray films of the chest. Nineteen of them had such severe symptoms that they required mechanical ventilatory assistance for periods ranging from 17 to 116 hours. During the follow-up period six of the 19 had radiologic evidence suggestive of pulmonary fibrosis or overexpansion or both. Only two had clinical evidence of frequent infections and expiratory wheezing that failed to respond to bronchodilator therapy; lung biopsies in these two indicated patchy areas of peribronchial and alveolar fibrosis. Subsequently, both showed clinical improvement. The clinical, radiologic and pathologic sequelae that occurred in these infants surviving clinical hyaline-membrane disease appear to result from the reparative process of the lung to the perinatal insult that produces the original disease.

Studies on infants with type II respiratory distress syndrome

A group of infants is described who seem to share clinical, biochemical, and physiologic similarities. The are prematurely born, but usually late in gestation, and frequently have a history of heavy maternal sedation or are delivered by cesarean section. Mild depression is often present at birth, and respiratory symptoms of grunting, chest-wall retraction, tachypnea, and flaring of the alae nasae appear soon after birth. The chest radiograph typically shows heavy central bronchovascular markings and overdistention of peripheral lung fields. These infants can be hyperoxygenated in 100 per cent oxygen throughout the course of their disease. There is early evidence of mildly to moderately severe combined metabolic and respiratory acidosis. They are normotensive for their size, and no significant shunting can be demonstrated through either the foramen ovale or the ductus arteriosus. Left ventricular output is within the normal range for size. The radiologic and physiologic findings usually permit differentiation from clinical hyaline membrane disease. Symptoms of respiratory distress subside gradually over the first 3 to 7 days of life, and residual pulmonary symptoms or radiologic abnormalities are absent. Subsequent motor and mental development are within normal limits.

Negative pressure assisted ventilation in infants with hyaline membrane disease

Since October, 1961, 80 infants thought to have potentially fatal hyaline membrane disease have received assisted ventilation with a negative pressure tank-type respirator as part of their intensive care management. Thirty-one (39 per cent) survived. It is thought that this form of therapy can be potentially life saving in severely ill infants whose birth weight is more than 1,500 grams and whose arterial PO 2 value while breathing 100 per cent oxygen is less than 40 mm. Hg.

Prognosis in hyaline-membrane disease. Use of a linear-discriminant.

THE pathological diagnosis of hyaline-membrane disease is made at autopsy in approximately 30 per cent1 of infants who die in the neonatal period. The characteristic pathological changes are found ...

THE MANAGEMENT OF RESPIRATORY FAILURE IN THE IDIOPATHIC RESPIRATORY DISTRESS SYNDROME OF PREMATURITY

The management of respiratory failure associated with idiopathic respiratory distress syndrome of prematurity, or, as we prefer to call it, clinical hyaline membrane disease, is an important facet in the therapy of this condition. However, it is the final stage of a program of management, and, in most instances, can be avoided by early attention to other aspects of the syndrome which pressage its occurrence. Respiratory failure usually follows a period of marked respiratory effort after birth, associated with decreasing lung compliance, progressive atelectasis, vascular congestion, and eventual physical exhaustion. Severe metabolic changes usually accompany this progressive deterioration with lactic acidemia and hyperkalemia often contributing to the clinical picture (TABLE 1 ) . Severe anoxemia, despite oxygen therapy, a falling arterial pH, and a rising PaC02, reflect the failure of both respiration and circulation to meet the infant’s needs. If, despite attempts at oxygenation and buffering of pH, an infant with severe hyaline membrane disease shows progressive anoxemia associated with decreasing respiratory effort, respiratory assistance is indicated. These events usually occur gradually over a period of several hours and may not develop until the infant has exhausted himself at 24 to 48 hours after birth. The premonitory signs are usually recognizable, although sudden respiratory arrest can occur without warning in a previously satisfactory baby. This may be due to a cardiac emergency such as an arrhythmia or standstill, to mucous plugging in the airway, to acute and overwhelming pulmonary edema or hemorrhage, or to a seizure. The baby whose course is gradually and inexorably downhill toward respiratory failure is much more common. One of the first warnings is the development of very irregular respiration followed by a gradual but steady decrease in respiratory rate and effort without other signs of improvement in a baby previously making maximum efforts to breathe. When the respiratory rate drops by 20 to 30/min. over a course of 30 to 60 minutes, especially if accompanied by deepening cyanosis, some type of ventilatory aid will be needed shortly. The cyanosis is usually ashy gray at this point due to extreme peripheral vasoconstriction, and the pH can be predictably estimated at a dangerously low level and dropping fast. Bradycardia may develop as deterioration progresses and conduction defects appear on the electrocardiogram. The infant ceases to breathe except for convulsive gasps. Ashy cyanosis becomes extreme and the baby dies if unassisted. Two types of ventilatory assistance have been used by us, each with advantages in certain circumstances and they can be combined on some occasions with good effect. The first and most widely available type of ventilatory assistance for infants is intermittent positive pressure insufflation of the lungs. This cannot be carried out for any prolonged period of time with a mask and requires tracheal intubation or tracheostomy. We have used a pressure control rather than a volume control system, although both are available. A maximum of 30 mm. Hg. or 40 cm. of water is the limit of pressure used and lower pressures are much preferred but not

The occurrence of pulmonaryfibrosis in children who had idiopathic respiratory distress syndrome

The long-term residua of the respiratory distress syndrome have not previously been assessed. Fifty-two infants who had clinical and x-ray evidence of RDS were examined at ages 6 months to 6 89 years, with evaluation of growth, development, and cardiopuhnonary problems. Posteroanterior and lateral chest x-rays were obtained; 19 infants were 6 to 11 months old~ 14 were 12 to 23 months, and 15 were over 24 months. All were apparently well, but 4 had clinical and x-ray findings of congenital heart disease With pulmonary hypervascularity and were excluded. Radiologic findings characteristic of pulmonary fibrosis were frequent, and have been graded as follows: (1) distinct linear densities radiating out from the hilum with peripheral branching, 12 children; (11) heavier, more generalized scarring extending far into the periphery, 17 children; (III) above findings plus overexpansion, extensive scarring, or pleural tenting, 6 children. The degree of pulmonary fibrosis could not be correlated with the clinical severity, birth weight, the duration or concentration of 02 therapy, the use of ventilatory aids, or the extent of x-ray changes in the acute stage. However, 21 of 29 children over 12 months of age had Class II or III pulmonary fibrosis; of these, only 6 had histories of intereurrent pulmonary disease, either bronchiolitis or asthma in each case. Of 48 infants who had RDS and have no evidence of eongenital heart disease, 48 per cent (23) have significant x-ray changes compatible with pulmonary fibrosis.

Observations on skin resistance to electricity and sweat chloride content. A preliminary report.

Summary Skin resistance to electrical current andsweat chloride values have been reported in 4 groups of children; white children in a control group; Negro children in a control group; white children with cystic fibrosis; and white children with central nervous system disease. The various groups studied could be distinguished both with respect to sweat chloride and skin resistance measurements. Further studies are under way to determine if the test can be developed to be useful as a screening and diagnostic procedure.