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101.
102.
Between November 2001 and September 2004, 80 patients aged 11 to 56 years (mean, 27.6 years) underwent the Ross operation. The mean preoperative New York Heart Association functional class was 2.37 +/- 0.72, and the mean ejection fraction was 52.8% +/- 16%. Aortic involvement included stenosis in 19 (24%) patients, regurgitation in 22 (28%), and both in 39 (49%). Root replacement was the technique used in all cases. The mean hospital stay was 5 days, and 74 patients (93%) were followed up for 4-48 months. Four-year actuarial survival rate was 96.25%. Postoperative echocardiography revealed no pulmonary autograft insufficiency in 50 patients (63%), trivial to mild insufficiency in 22 (28%), moderate insufficiency in 2 (3%), and severe insufficiency in one (1%). Two patients required autograft re-intervention. Postoperative echocardiography of the pulmonary homograft valve showed severe stenosis (peak gradient > 50 mm Hg) in 2 patients, and moderate stenosis (peak gradient 25-50 mm Hg) in one. The mean postoperative left ventricular ejection fraction was 51.4%. The Ross operation can be considered an elegant alternative to prosthetic valves in the treatment of aortic valve diseases in developing countries.  相似文献   
103.
Because adrenergic beta antagonists are not sufficient to prevent atrial fibrillation after coronary artery bypass grafting, this prospective, randomized trial was designed to evaluate the effects of ascorbic acid as an adjunct to beta-blockers. Fifty patients formed our ascorbic acid group, and another 50 patients formed our control group. All patients were older than 50 years, were scheduled to undergo coronary artery bypass grafting, and had been treated with beta-blockers for at least 1 week before surgery. The mean age of the population was 60.19+/-7.14 years; 67% of the patients were men. Patients in the ascorbic acid group received 2 g of ascorbic acid on the night before the surgery and 1 g twice daily for 5 days after surgery. Patients in the control group received no ascorbic acid. Patients in both groups continued to receive beta-blockers after surgery. Telemetry monitoring was performed in the intensive care unit, and Holter monitoring was performed for 4 days thereafter. The incidence of postoperative atrial fibrillation was 4% in the ascorbic acid group and 26% in the control group (odds ratio, 0.119; 95% confidence interval, 0.025-0.558, P = 0.002). We conclude that ascorbic acid is effective, in addition to being well-tolerated and relatively safe. Therefore, it can be prescribed as an adjunct to beta-blockers for the prophylaxis of post-bypass atrial fibrillation.  相似文献   
104.
Hyperbaric oxygen therapy for severe acute pancreatitis   总被引:2,自引:0,他引:2  
Despite improvements in the supportive management of severe acute pancreatitis over the last decade, the morbidity and mortality rate remains high. The main feature of this condition is pancreatic necrosis leading to sepsis, with both localized and systemic inflammatory response syndromes. Early pathophysiological changes of the pancreas include alterations in microcirculation, ischemia reperfusion injury, and leukocyte and cytokine activation. The efficacy of hyperbaric oxygen (HBO) therapy in improving these pathophysiological disturbances is documented for various conditions. However, its effect in the treatment of severe acute pancreatitis is undetermined. This report documents the case of a 56-year-old woman presenting with severe acute pancreatitis treated by HBO therapy. The severity of disease was based on an Acute Physiology and Chronic Health Evaluation (APACHE II) illness grading score of 11 and a Baltazar based computed tomography severity index (CTSI) score of 9. Administration of 100% oxygen was commenced within 72 h of presentation at a pressure of 2.5 atmospheres for 90 min and given twice daily for a total of 5 days. Therapy was well tolerated with improvements in APACHE II and CTSI grading scores. HBO therapy for severe acute pancreatitis appeared to be safe and may have a role in improving treatment outcomes. Further study is required.  相似文献   
105.
Partial cholecystectomy (PC) is an alternative choice to standard cholecystectomy in situations with increased risk of Calot's components injury. We reported our experience with the patients treated with PC and reviewed the literature. Fifty-four patients with complex acute cholecystitis underwent PC, including conventional partial cholecystectomy (CPC; n = 48) and laparoscopic partial cholecystectomy (LPC; n = 6). The clinical diagnosis was verified by ultrasonography. In addition, we reviewed 1190 published cases (1972-2005) who underwent a "nonconventional" surgery for severe cholecystitis, including cholecystostomy, CPC, or LPC. Review of the literature, including our cases, showed a male:female ratio of 1.3:1. The major operative indication was severe acute cholecystitis. Procedures included cholecystostomy (65.8%) and PC (34.2%). In the follow-up (n = 1190), biliary leak (4.8%), retained stones (4.6%), recurrent symptoms (2.3%), wound infections (1.9%), persistent biliary fistula (0.9%), and prolonged biliary drainage (0.2%) were found, with an overall mortality rate of 9.4 per cent. In 133 patients, because of postoperative complications (e.g., recurrent symptoms, remaining common bile duct stones, or persistence of bile fistula), reoperation was necessary, including 121 cases (90.1%) of cholecystectomy, whereas the other 11 patients underwent other procedures such as common bile duct exploration or closure of the fistula. The surgical trend for complex acute cholecystitis treatment has been changed from only cholecystostomy to a spectrum of cholecystostomy, CPC, and LPC with the progressive increase of PC. The proportion of the LPC compared with CPC has also increased during recent years. It seems that PC is a safe procedure for treating complicated acute cholecystitis. Whether the indication and need for alternative techniques to standard cholecystectomy is changing should be evaluated in future studies.  相似文献   
106.

Objective

The antimalarial medication hydroxychloroquine has been proposed as a thromboprotective agent in systemic lupus erythematosus (SLE), but studies thus far have been limited by the possibility of confounding by indication. This study was conducted to assess whether exposure to antimalarial drugs is associated with a decrease in thrombovascular events (TEs) in patients with SLE.

Methods

The study was designed as a nested case–control study embedded in an inception cohort of patients with SLE, which allowed adjustments for possible confounding by calendar year, duration of disease, duration of observation, and severity of lupus. After controlling for the possible confounding variables in conditional logistic regression models, the use of antimalarial drugs was assessed for its effects on the development of TEs in lupus patients.

Results

Fifty‐four cases of TE were identified, and these were matched with 108 control subjects (lupus patients without TEs). Univariate analyses identified older age (odds ratio [OR] 1.04, 95% confidence interval [95%CI] 1.01–1.07) or being older than age 50 years (OR 3.5, 95% CI 1.4–8.6) and ever having hypertension (OR 2.5, 95% CI 1.0–5.8) as being associated with an increased risk of TEs, whereas use of antimalarial drugs (OR 0.31, 95% CI 0.13–0.71) was associated with a decreased risk of TEs. Separate analyses were done for arterial and venous TEs, which yielded similar results. In multivariate analyses, use of antimalarial drugs (OR 0.32, 95% CI 0.14–0.74) and older age (OR 1.04, 95% CI 1.01–1.07) were the only 2 variables that remained significant.

Conclusion

The results from this nested case–control study demonstrate that, after accounting for the effects of disease severity, disease duration, and calendar year, antimalarial drugs were found to be thromboprotective, being associated with a 68% reduction in the risk of all TEs, with a range of risk reduction of at least 26% up to as high as 86%.
  相似文献   
107.
Objective To examine the effect of psychosocial and physical factors, and demographic variables on low back pain in nurses. The roles of physical and psychosocial factors to low back pain investigated separately, however psychosociophysical model for it require further research especially among nurses. Methods Participants included 261 males and 162 females randomly selected from Namazi, Shahid Faghihi, Shahid Beheshty, and Shahid Chamran hospitals in Shiraz, Iran. A demographic questionnaire, the Low Back Pain Scale, Psychosocial Factor Scale and Physical Factor Scale were used in the study. Results The resulting data showed that in this particular sample psychosocial and physical factors relatively explain low back pain for total sample and both genders, when using a multiple regression model. The MANOVA indicated that gender, marital status, age, education, ethnicity, hospital and ward, type of working shift, type of responsibility in hospital, level of education, professional experience, and aged-group demographical variables are effective in low back pain, and physical and psychosocial factors related to LBP for nurses. Conclusions Significant findings were explained within a psychosociophysical framework for low back pain prevention among nurses and further research trends.  相似文献   
108.
109.
We investigate an incident in which a carbon dioxide absorber caused difficulty with ventilation. The problem as it developed throughout the anesthetic, and clues that led to the determination that the carbon dioxide canister was the problem, is discussed.  相似文献   
110.
Despite the well-recognized role of platelets in the pathogenesis of acute myocardial infarction (AMI) and in the vascular responses to angioplasty, the relation between platelet count and outcomes after primary percutaneous coronary intervention (PCI) in AMI is unknown. We therefore determined the effect of baseline platelet count on clinical and angiographic outcomes of patients with AMI undergoing primary PCI. In the prospective, randomized CADILLAC trial, platelet count on admission was available in 2,021 of 2,082 patients (97.0%). Angiographic results and outcomes at 30 days and 1 year were stratified by quartiles of platelet count. Median platelet count was 231 x 10(9)/L (range 38 to 709). Primary PCI angiographic success rates were independent of platelet count. The 30-day incidence of target vessel thrombosis or reocclusion increased steadily across the higher quartiles of baseline platelet count (0.2%, 0.6%, 1.0%, and 2.0%, p = 0.027). At 1 year, patients with a baseline platelet count >or=234 versus <234 x 10(9)/L had higher rates of death or reinfarction (8.9% vs 4.5%, p <0.0001), death (5.8% vs 3.1%, p = 0.002), and reinfarction (3.4% vs 1.6%, p = 0.008). By multivariable analysis, a higher baseline platelet count was the strongest predictor of 1-year death or reinfarction (hazard ratio [HR] per 10,000 increase in platelet count 1.02, 95% confidence interval [CI] 1.02 to 1.07, p <0.0001) and independently predicted reinfarction (HR 1.06, 95% CI 1.02 to 1.09, p = 0.002) and cardiac mortality (HR 1.03, 95% CI 1.00 to 1.06, p = 0.055) at 1 year. In conclusion, a higher baseline platelet count in patients with AMI is a powerful independent predictor of death and reinfarction within the first year after primary PCI.  相似文献   
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