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BACKGROUND: Ventilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients. METHODS: The authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as "early-onset" (< 5 days) and "late-onset," determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates: Pseudomonas aeruginosa, Acinetobacter baumanii, methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression. RESULTS: Among 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, including Pseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes), Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0-20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4-64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3-11.3). A. baumanii-related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5-133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1-32.6). CONCLUSIONS: The authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused by A. baumanii.  相似文献   
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Acute myocardial infarction (AMI) is a rare, but possibly catastrophic event during pregnancy, delivery, or puerperium, leading to a high mortality rate. It has different pathogenic mechanisms, such as atherosclerosis, vasospasm, thrombosis, and coronary dissection. Although MI has been reported in pregnant women at all stages of pregnancy and postpartum, it occurs more commonly in the third trimester. Pregnancy-associated MI most commonly involves the anterior wall. Pregnancy itself is an independent risk factor for MI, conferring a fourfold higher risk than that of nonpregnant women matched for age. We report the case of a 27-year-old primigravida at 30 weeks’ gestation presenting with anterior MI, secondary to severe stenosis of the left anterior descending coronary artery, treated with emergency percutaneous coronary intervention.  相似文献   
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Aims To evaluate the long term results of tongue base reduction with hyoepiglottoplasty as a surgical option in the treatment of severe obstructive sleep apnea. Material and Method Severe obstructive sleep apnea patients diagnosed as upper airway narrowing at the tongue base level were treated with transcervical tongue base reduction with hyoepiglottoplasty. Seven years after single stage multilevel surgery, the patients were reevaluated clinically, radiologically and polysomnographic records were taken. Preoperative, early postoperative and long-term postoperative parameters were compared to determine the success rate of the surgical technique. Results In the postoperative long-term follow-up Epworth sleepiness scale (ESS) scores were reduced to 4 and 6 respectively 2 months after surgery despite the initial values of 17 and 15. BMI were decreased from 29.7 and 27.9 kg/m2 respectively to 26 and 24 kg/m2. The apnea/hypopnea index (AHI) were reduced to 14.1 and 16.2 respectively from 68.6 and 83.83. O2 nadir was 55 and 66% respectively and improved to 86 and 89%. Flexible nasopharyngoscopy revealed competent airway in both retropalatal and retroglossal level. Bed partners scored snoring as 2/10 and 4/10 corresponding to very mild and moderate. Daytime somnolence and witnessed apneic periods were completely disappeared in both patients. Conclusion Open tongue base resection with hyoepiglottoplasty is effective among all other surgical corrections of sleep apnea even after 7 years postoperatively.  相似文献   
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Aortic dissection is extremely rare in children. Although it usually presents with severe chest pain, atypical clinical presentations mimicking various illnesses may cause misdiagnosis. In this report, the case of a 14‐year‐old boy with symptoms suggestive of acute abdomen, which was finally diagnosed as aortic dissection, is discussed.  相似文献   
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Background: Sildenafil citrate may have direct cardiac electrophysiological effects, and is possibly responsible for some cardiac events. The aim of our study was to investigate the effects of sildenafil citrate on QT dynamicity properties with a new QT analysis program showing even small changes in ventricular repolarization. Methods: Twenty‐four‐hour Holter electrocardiographic recordings were used to obtain the data in the predrug phase (1‐hour rest position before drug administration), and in the postdrug phase (1‐hour rest position, which began 60 minutes after 50 mg oral sildenafil citrate administration). With the special QT analysis program (Verda, Reynolds Medical Ltd., UK); mean values of RR, QT, QTo (corrected QT), J (the exponent of correction formula) and S (QT/RR plots slope) parameters together with QT variability indexes (QTVI) were calculated for study phases. Results: Mean ± SEM values for RR and QT were higher in postdrug phase than in predrug phase (RR: 845 ± 42 ms vs 816 ± 46 ms, P < 0.05; QT: 371 ± 8 ms vs 361 ± 9 ms, P < 0.05). However, sildenafil did not induce any significant change in mean ± SEM values for QTo, J, and S in postdrug phase compared with predrug phase (408 ± 10 ms vs 406 ± 8 ms, 0.474 ± 0.030 vs 0.433 ± 0.025, 0221 ± 0.020 vs 0.198 ± 0.017, respectively; P > 0.05). QTVIs were also not different in each phase (predrug: ?0.874 ± 0.071 vs postdrug: ?0.997 ± 0.067, P = 0.109). Conclusions: Fifty milligrams sildenafil does not affect QT dynamicity properties. The cardiac events associated with sildenafil could not be explained with ventricular arrhythmias.  相似文献   
20.

Purpose

In this study, we aimed to establish a quantitative threshold value in the diagnosis of subacromial impingement syndrome by measuring the thickness of the subacromial bursa during abduction and adduction.

Materials and methods

Forty-five patients with subacromial impingement syndrome and 54 healthy individuals underwent dynamic shoulder ultrasonography. The subacromial bursa, between the supraspinatus tendon margin and peribursal adipose tissue, was measured between the acromion and humeral head at its widest part. The subacromial impingement ratio was calculated by dividing the subacromial bursa thickness during abduction to the subacromial bursa thickness during adduction. Shapiro–Wilk test was used in the assessment of normal distribution of parameters.

Results

The mean subacromial bursa thickness in the abduction position was 1.8 ± 1.1 mm in the study group and 0.9 ± 0.3 mm in the control group. The mean subacromial bursa thickness in the adduction position was 0.9 ± 0.5 mm in the study group and 0.8 ± 0.3 mm in the control group. The subacromial impingement ratio showed a statistically significant difference between groups (p < 0.0001), and the ratio being 2.0 ± 0.5 in the study group and 1.2 ± 0.1 in the control group. For measurements performed in the abduction position, the best cut-off value was calculated as 1.3 mm, and sensitivity and specificity were 70.6 and 85.2%, respectively. The best cut-off value was 1.4 for the subacromial impingement ratio, and sensitivity and specificity were 88.2 and 96.3%, respectively.

Conclusion

Subacromial impingement ratio is a very practical and reliable method in subacromial impingement syndrome diagnosis.
  相似文献   
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