Congenital bacterial sepsis in very preterm infants.

The results of body fluid and surface cultures from 148 preterm infants less than 33 weeks gestational age obtained routinely on admission to a neonatal intensive care unit were reviewed. The aim was to determine the occurrence of congenital bacterial sepsis in this population and to examine whether surface cultures yielded information helpful in management. Gastric aspirate and umbilical, nasal and ear swabs were cultured and the results were compared to those of blood cultures. Nine infants (5.4%) had congenital bacterial sepsis diagnosed by positive blood cultures. Only the results of microscopy of gastric aspirate were available within hours of birth and before the results of blood culture. Microscopy of gastric aspirate, demonstrating pus cells, alone had a sensitivity of 0.86 in predicting congenital sepsis but a specificity of 0.49; the specificity, however, rose to 0.80 if both organisms and pus cells were observed on microscopy. Thus, only this combination was a useful pre-indicator of congenital sepsis. In infants who did not develop septicaemia, treatment was modified only if Streptococcus agalactiae was cultured from surface sites; in all such cases, the organism was grown from the ear swab. Our results demonstrate that congenital bacterial sepsis is common amongst very preterm infants admitted for neonatal intensive care but routine screening of surface cultures should be restricted to an ear swab only.     

Asbestos-related focal lung masses: manifestations on conventional and high-resolution CT scans

In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances.     

High-resolution CT diagnosis of emphysema in symptomatic patients with normal chest radiographs and isolated low diffusing capacity.

To determine the prevalence of "nonobstructive" (impairment of gas transfer) emphysema in a select population of smokers with dyspnea, a retrospective study of patients with emphysema evident at high-resolution computed tomography (HRCT) was undertaken. Four hundred seventy HRCT studies were reviewed. In 47 cases, centrilobular emphysema was the dominant or sole parenchymal abnormality. Concomitant chest radiographs were available in 41 of these cases; 16 of the 41 lacked radiographic findings of emphysema. Among these 16 patients, pulmonary function testing revealed 10 to have normal flow rates (ratio of forced expiratory volume in 1 second to forced vital capacity and forced expiratory volume in 1 second greater than 80% predicted) and impaired gas transfer (single-breath carbon monoxide diffusing capacity [DLCOSB] less than 80% predicted). With the exclusion of one patient with congestive heart failure from the group of 10, the severity of emphysema at HRCT correlated inversely with DLCOSB (r = -.643). These results indicate that HRCT allows detection of emphysema in symptomatic patients when chest radiographs and pulmonary function tests are nondiagnostic.     

Nonbronchoscopic bronchoalveolar lavage for the diagnosis for Pneumocystis carinii pneumonia in the acquired immunodeficiency syndrome

We compared conventional bronchoscopic transbronchial biopsy (TBB) and bronchoalveolar lavage (BAL) with non-bronchoscopic bronchoalveolar lavage (NB-BAL) in nine patients with acquired immunodeficiency syndrome (AIDS) and bilateral lung infiltrates. NB-BAL was carried out with a control-tipped reusable catheter. In each patient, bronchoscopic procedures were performed in the right lung, followed immediately by NB-BAL in the left lung. The specimens obtained by NB-BAL confirmed the presence of P carinii pneumonia in seven of eight patients in whom the diagnosis was established by TBB or BAL. Viral cultures of NB-BAL specimens yielded cytomegalovirus (CMV) in four of five subjects with evidence of CMV via bronchoscopic technique, including two instances in which CMV was not detected by BAL. Complications were limited to right-sided pneumothorax attributable to TBB. Accuracy of NB-BAL appears to be comparable to that of conventional bronchoscopic approaches in the diagnosis of AIDS-related pulmonary infection with P carinii or CMV. NB-BAL may be a safer and more economical alternative to TBB and BAL in the diagnosis of pulmonary opportunistic infections.     

Randomised controlled trial of two methods of weaning from high frequency positive pressure ventilation.

Forty preterm infants suffering from respiratory distress syndrome were entered into a randomised controlled trial to assess the importance of the length of inspiratory time during weaning from high frequency positive pressure ventilation (HFPPV). Two weaning regimes were compared: in one (group A) inspiratory time was limited to 0.5 seconds throughout weaning, in the other (group B) ventilator rate was reduced by increasing both inspiratory and expiratory time (inspiration:expiration ratio constant) until inspiratory time reached 1.0 seconds. At ventilator rates of 20 and 40 breaths/minute an acute comparison was made in all 40 infants of the two inspiratory times; despite the lower mean airway pressure associated with the shorter inspiratory time blood gases were maintained. There was no difference in the incidence of pneumothoraces or need for reventilation between the two regimens but infants in group A had a shorter duration of weaning. We conclude limitation of inspiratory time to 0.5 seconds during weaning from HFPPV is advantageous to preterm infants with respiratory distress syndrome.     

Immediate effects of albumin infusion in ill premature neonates.

Ten normotensive premature infants with idiopathic respiratory distress syndrome, and albumin concentrations of less than 30 g/l were given 5 ml/kg of 20% salt poor albumin by infusion. Concentrations measured six hours after infusion had increased significantly and these were associated with significant reduction in weight and improvement in urine output.     

Pulmonary interstitial emphysema in very low birthweight infants.

Forty six of 142 infants weighing less than 1500 g at birth, who had chest radiographs in the first 5 days of life, developed pulmonary interstitial emphysema (PIE) and in 19 this occurred in the first 24 hours. PIE was seen more frequently in infants weighing less than 1000 g at birth (24 of 57) than in those weighing 1000-1500 g (22 of 85). Ventilation for hyaline membrane disease was strongly associated with PIE, and only babies who were resuscitated, or ventilated, or had hyaline membrane disease developed the disorder. Most pneumothoraces were preceded by x-ray appearances of PIE (17 of 21). Mortality was increased in ventilated infants who developed PIE and was high in those with severe x-ray changes.