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Notizen: Abstract We performed a multicenter prospective randomized controlled trial to determine the efficacy and safety of the surfactant preparation, Survanta (Abbott Laboratories, Chicago, USA), for 750–1750 g infants with idiopathic respiratory distress syndrome, (IRDS) receiving assisted ventilation with 40% or more oxygen. One hundred and six eligible infants from the eight participating centers were randomly assigned between March 1986 and June 1987 to receive either surfactant (100 mg phospholipid/kg, 4 ml/kg) or air (4 ml/kg) administered into the trachea within 8 h of brith (median time of treatment 6.2 h, range 3.2–9.1 h). The study was stopped before enrollment was completed at the request of the United States Food and Drug Administration when significant differences were observed in incidence of periventricular-intraventricular hemorrhage (PIH), between the surfactant treated and control infants. Surfactant treated infants had larger average increases in the arterial-alveolar oxygen ratio, (a/A ratio) (P〈0.0001), and larger average decreases in FiO2 (P〈0.0001) and mean airway pressure, (MAP) (P〈0.017) than controls over the 48 h following treatment. The magnitude of the differences between the surfactant and control groups were 0.19 (SE=0.03) for a/A ratio, −0.28 (SE=0.04) for FiO2 and −1.7 cm H2O (SE=0.70) for MAP. The clinical status on days 7 and 28 after treatment was classified using four predefined ordered categories: (1) no respiratory support; (2) supplemental O2 with or without continuous positive airway pressure (CPAP); (3) intermittent mandatory ventilation; and (4) death. There were no statistically significant differences in the status categories on days 7 or 28 between surfactant and control infants. There were no significant differences between the groups with respect to the incidence of patent ductus arteriosus, bronchopulmonary dysplasia, necrotizing entero-colitis, air leaks or death. There was a statistically significant difference between treated and control infants in the frequency and severity of periventricular-intraventricular hemorrhage (PIH) (Cochran-Mantel-Haenszelχ 2adj=6.36,P=0.01). Hemorrhages occurred in 59.6% of surfactant treated infants and 26.9% of controls. Severe hemorrhages (grades 3 or 4) occurred in 38.5% of surfactant treated infants and 15.4% of controls (χ 2adj=4.01,P=0.045). We conclude that the intratracheal administration of Survanta prior to 8 h of age to infants with IRDS receiving assisted ventilation with 40% or more oxygen results in a reduction in the severity of respiratory distress during the 48 h after therapy. Because of the difference in incidence of PIH between surfactant and control infants in this study, we recommend that future clinical trials of surfactant include more frequent prospective serial ultrasound evaluations for diagnosis of hemorrhage.

Notizen: Summary In order to evaluate the relation between balloon design (monofoil, trefoil) and valvular configuration, experimental aortic valvuloplasty was performed in four post-mortem hearts with calcific aortic stenosis of various morphology. The degree of obstruction of the aortic orifice was assessed by computed axial tomography during inflation of monofoil 15 and 19 mm and trefoil 3×12 mm balloon catheters. We also evaluated the hemodynamic repercussion of balloon inflation (fall in systolic aortic pressure) in four elderly patients with acquired aortic stenosis who underwent a percutaneous transluminal aortic balloon valvuloplasty, with stepwise increasing balloon sizes of 15 mm, 19 mm and 3×12 mm, as during ourin vitro experiments, and who underwent aortic valve replacement later on. In these patients, we correlated the anatomy of the excised aortic valves with the retrospective analysis of aortic pressure curves recorded during previous valvuloplasty procedures. Our experimental and clinicopathological observations showed that the degree of obstruction of the aortic orifice in post-mortem specimens and the tolerance to balloon inflation in live patients are dependent of the valvular configuration. Although trefoil balloons have the theoretical advantage to avoid complete obstruction of the aortic orifice during inflation, we observed that in presence of a tricuspid configuration, they could be potentially more occlusive than monofoil balloons since each of the 3 individual components of the trefoil balloon occupied the intercommissural spaces while inflated. However, they offered more residual free space when inflated in aortic valves with a bicuspid configuration (i.e. congenitally bicuspid valves or tricuspid valves with one fused commissure). In our opinion, these observations are relevant, since degenerative disease of the aortic valve (i.e. tricuspid valve without commissural fusion) is now recognized as the most common etiology of aortic stenosis in the elderly.