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OBJECTIVE: To test the hypothesis that high-frequency jet ventilation (HFJV) will reduce the incidence and/or severity of bronchopulmonary dysplasia (BPD) and acute airleak in premature infants who, despite surfactant administration, require mechanical ventilation for respiratory distress syndrome. DESIGN: Multicenter, randomized, controlled clinical trial of HFJV and conventional ventilation (CV). Patients were to remain on assigned therapy for 14 days or until extubation, whichever came first. Crossover from CV to HFJV was allowed if bilateral pulmonary interstitial emphysema or bronchopleural fistula developed. Patients could cross over to the other ventilatory mode if failure criteria were met. The optimal lung volume strategy was mandated for HFJV by protocol to provide alveolar recruitment and optimize lung volume and ventilation/perfusion matching, while minimizing pressure amplitude and O2 requirements. CV management was not controlled by protocol. SETTING: Eight tertiary neonatal intensive care units. PATIENTS: Preterm infants with birth weights between 700 and 1500 g and gestational age <36 weeks who required mechanical ventilation with FIO2 >0.30 at 2 to 12 hours after surfactant administration, received surfactant by 8 hours of age, were <20 hours old, and had been ventilated for <12 hours. Outcome Measures. Primary outcome variables were BPD at 28 days and 36 weeks of postconceptional age. Secondary outcome variables were survival, gas exchange, airway pressures, airleak, intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), and other nonpulmonary complications. RESULTS: A total of 130 patients were included in the final analysis; 65 were randomized to HFJV and 65 to CV. The groups were of comparable birth weight, gestational age, severity of illness, postnatal age, and other demographics. The incidence of BPD at 36 weeks of postconceptional age was significantly lower in babies randomized to HFJV compared with CV (20.0% vs 40.4%). The need for home oxygen was also significantly lower in infants receiving HFJV compared with CV (5.5% vs 23.1%). Survival, incidence of BPD at 28 days, retinopathy of prematurity, airleak, pulmonary hemorrhage, grade I-II IVH, and other complications were similar. In retrospect, it was noted that the traditional HFJV strategy emphasizing low airway pressures (HF-LO) rather than the prescribed optimal volume strategy (HF-OPT) was used in 29/65 HFJV infants. This presented a unique opportunity to examine the effects of different HFJV strategies on gas exchange, airway pressures, and outcomes. HF-OPT was defined as increase in positive end-expiratory pressure (PEEP) by >/=1 cm H2O from pre-HFJV baseline and/or use of PEEP of >/=7 cm H2O. Severe neuroimaging abnormalities (PVL and/or grade III-IV IVH) were not different between the CV and HFJV infants. However, there was a significantly lower incidence of severe IVH/PVL in HFJV infants treated with HF-OPT compared with CV and HF-LO. Oxygenation was similar between CV and HFJV groups as a whole, but HF-OPT infants had better oxygenation compared with the other two groups. There were no differences in PaCO2 between CV and HFJV, but the PaCO2 was lower for HF-LO compared with the other two groups. The peak inspiratory pressure and DeltaP (peak inspiratory pressure-PEEP) were lower for HFJV infants compared with CV infants. CONCLUSIONS: HFJV reduces the incidence of BPD at 36 weeks and the need for home oxygen in premature infants with uncomplicated RDS, but does not reduce the risk of acute airleak. There is no increase in adverse outcomes compared with CV. HF-OPT improves oxygenation, decreases exposure to hypocarbia, and reduces the risk of grade III-IV IVH and/or PVL.  相似文献   
998.
Three hundred patients, comprising of 210 men and 90 women, with internal haemorrhoids (grade I and II) were subjected to cryosurgery. There was good destruction of piles in 270 (90%) patients while in 30 (10%) patients residual pile mass was present requiring further treatment The result was compared with 100 patients of grade II haemorrhoids who underwent formal haemorrhoidectomy during the same period. It was observed that rate of complications was lower in those who underwent cryosurgery.KEY WORDS: Cryosurgery, Haemorrhoids  相似文献   
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Radical prostatectomy has been considered the gold standard for the curative treatment of clinically localized prostate cancer. After an extensive review of the literature, we concluded that surgery probably functions primarily as a tumor debulking procedure rather than a curative one. Morphometric studies suggest that the majority of patients undergoing surgery have tumors too large for cure. Histologic studies demonstrate that 55% of radical prostatectomy specimens show evidence of extraprostatic disease and approximately 15% have tumors so small that a clinical impact on longevity is unlikely. Thus, only 30% of patients have surgery that is clearly beneficial on a histopathologic basis. Given the rather long doubling time of prostate cancers, many patients with residual cancer following surgery die of other causes, giving the false impression of cure. However, long-term studies in men with positive surgical margins have demonstrated that the majority die from prostate cancer. Furthermore, using prostate specific antigen as a measure of progression, the biochemical disease-free survival rates are substantially lower than the cause-specific survival rates. Although radical prostatectomy may be the best tumor debulking procedure available, it is associated with substantial morbidity and cost. This information is important for both physician and patient when deciding on management of prostate cancer.  相似文献   
1000.
Twelve cases of intracardiac tumours operated during the period 1975 to 1994 are presented. There were 8 males and 4 females in the age range of 18 years to 64 years. Tumours were located in the left atrium in 10 patients and in the right atrium in 2 patients. Standard cardiopulmonary techniques were followed. The right atrial tumours were approached through a right atrial incision while the left atrial tumours were approached through a bi-atrial trans-septal approach. One patient underwent a perineal urethrolithotomy for an impacted urethral calculus at the same sitting. Eleven of the tumour masses excised were myxomas confirmed on histopathology. The last patient, operated for synovial sarcoma of the left knee 2 years before, presented with a metastatic tumour mass in the left atrium. No deaths occurred in the series.KEY WORDS: Heart neoplasms, Heart surgery, Myxomas  相似文献   
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