No abstract

Pulmonary alveolar proteinosis (PAP) may develop in a primary (idiopathic) form, chiefly during middle age, or less commonly in the setting of inhalational exposure, hematologic malignancy, or immunodeficiency. Current research supports the theory that PAP is the result of pathophysiologic mechanisms that impair pulmonary surfactant homeostasis and lung immune function. Clinical symptomatology is variable, ranging from mild progressive dyspnea to respiratory failure. There is a strong association with tobacco use. The predominant computed tomographic feature of PAP is a "crazy-paving" pattern (smoothly thickened septal lines on a background of widespread ground-glass opacity), often with lobular or geographic sparing. The radiologic differential diagnosis of crazy-paving includes pulmonary edema, pneumonia, alveolar hemorrhage, diffuse alveolar damage, and lymphangitic carcinomatosis. Definitive diagnosis is made with lung biopsy or bronchoalveolar lavage specimens that reveal intraalveolar deposits of proteinaceous material, dissolved cholesterol, and eosinophilic globules. Symptomatic treatment includes whole-lung lavage, and multiple procedures may be required. New therapies directed toward the identified defect in immune defense have met with moderate clinical success.

Ninety-seven one-hour recordings of the abdominal fetal electrocardiogram (ECG) were made from 59 normal patients between 21 and 41 weeks of gestation. The heart intervals, measured between successive R-waves, were analysed by computer. The signal-to-noise ratio of the fetal ECG limited the precision of the interval measurements to approximately one millisecond. The characteristics of the baseline heart rate changed significantly as gestation advanced, the mean R-R interval, the standard deviation of the intervals and the standard deviation of the interval differences all increasing with gestation (p <0*001). In later gestation the baseline heart rate during periods of fetal rest differed significantly from that during periods of fetal activity; during rest the mean R-R interval was greater (p <0.001) and the standard deviations of the intervals and interval differences were smaller (p < 0.001). Examination of the coefficient of variation of the heart intervals gave a result which contradicted the significance of this measurement as an index of fetal welfare as proposed by Curran and MacGregor (1970).COMPUTER analysis of the fetal heart rate (FHR) can provide an objective means of condensing the large quantity of information which results from continuous monitoring of the fetus. In particular, a more accurate analysis of cardiac beat-to-beat variation can be obtained com-* Present address: Department of Obstetrics and Gynaecology, John Radcliffe Hospital, Headington, Oxford OX3 9DU. pared with that provided by conventional FHR monitors. The relatively slow recording speeds of the latter, combined with the small scales allowed for the display of the heart rate, make it difficult to distinguish the changes in rate from beat to beat. Furthermore the scales, being linear to frequency, compress the changes in heart interval at the lower rates and expand them at higher rates.Reliable observations of heart interval can 186

Given the new standards established by the Accreditation Council for Graduate Medical Education, residency directors can increase on-call sleep for residents by reducing the number of pages and admissions.