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OBJECTIVE: To identify preoperative and perioperative features that may lead to a risk of surgical-site infection (SSI) after coronary artery bypass surgery. DESIGN: 884 patients who underwent coronary artery bypass grafting in 1992 and 1993 were studied. The associations between 23 preoperative and perioperative features and the presence of SSI at the donor site or in the chest area were evaluated by univariate analysis followed by multivariate logistic regression analysis. SETTING: A university hospital. RESULTS: 172 patients (19.5%) either had an SSI recorded before discharge or had received antibiotics prescribed for a suspected SSI during the 1-month surveillance period after discharge. Multivariate logistic regression analysis showed an extreme body mass index (BMI; P=.015), female gender (P=.023), and chronic obstructive pulmonary disease (COPD; P=.030) to be independent risk features for SSI. The donor site was infected in 136 patients (15.4%), an event for which female gender (P=.003) was the only independent risk feature. Forty-seven patients (5.3%) had an SSI of the chest area, with diabetes (P=.003) and extreme BMI (P=.010) as independent risk features. CONCLUSION: Extreme BMI, female gender, and COPD are highly significant independent predictors of the development of SSI. Female gender is a risk feature specifically for SSI at the donor site, whereas diabetes and extreme BMI predict it in the chest area.  相似文献   
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Myocardial perfusion SPECT using the prone position improves inferior wall counts and decreases motion problems as compared with the usual supine position. Nonetheless, it is not suitable for women. In addition, it is associated with artifactual anteroseptal defects and hot spots. METHODS: The right lateral (RL) position was evaluated instead of the prone position in 72 patients (26 women). RL imaging was performed immediately after the supine imaging during a routine 2-day 99mTc-sestamibi exercise protocol. The SPECT images were scored semiquantitatively by three physicians. Moreover, regional myocardial counts, as well as extent and severity of defects, were assessed by quantitative polar map analysis. RESULTS: All patients tolerated the RL position well and there was no significant patient movement in either position. Higher inferior myocardial counts per pixel were observed in the RL than in supine images. Inferior wall defects (especially mild ones) were more common in the supine than the RL images, whereas defects in other regions were not different. Quantitative analysis confirmed these findings. Analysis of 34 patients with recent coronary arteriography revealed an overall coronary artery disease (CAD) supine- and RL-imaging specificity of 50% and 75%, respectively, and the sensitivities of both were 93%. Right CAD sensitivity, specificity and normalcy rates for the supine position were 100%, 44% and 55%, whereas those of the RL position were 94%, 75% and 90%, respectively. CONCLUSION: The RL position improves CAD diagnostic accuracy, particularly right CAD, without significant artifacts in other myocardial regions. Unlike the prone position, the RL position is well tolerated by both women and men.  相似文献   
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The role of nitric oxide in inflammatory responses to substance P and other mediators of inflammation was examined in rat skin microvasculature in a blister base raised on the hind footpad. Superfusion of substance P (1 microM) over the blister base caused an increase in plasma extravasation and a vasodilator response which was not maintained. N(G)-Nitro-L-arginine (100 microM), an inhibitor of nitric oxide biosynthesis, attenuated vasodilatation and plasma extravasation due to substance P. The inactive isomer N(G)-nitro-D-arginine was without effect. Neurokinin A (1 microM), 5-hydroxytryptamine (1 microM), ATP (50 microM) and vasoactive intestinal polypeptide (1 microM) elicited vasodilation, which for vasoactive intestinal polypeptide was maintained even after washout. 5-Hydroxytryptamine and neurokinin A, but not ATP or vasoactive intestinal polypeptide, significantly increased plasma extravasation. Vasodilatation to neurokinin A, 5-hydroxytryptamine and ATP, and the increase in plasma extravasation due to neurokinin A and 5-hydroxytryptamine were unaffected by N(G)-nitro-L-arginine (100 microM), whereas vasodilation due to vasoactive intestinal polypeptide was significantly attenuated. These findings suggest that in rat skin microvasculature in vivo, nitric oxide is involved in vasodilator responses due to substance P and vasoactive intestinal polypeptide, and plasma extravasation due to substance P, but does not contribute significantly to vasodilatation induced by neurokinin A, 5-hydroxytryptamine or ATP, or the plasma extravasation induced by neurokinin A or 5-hydroxytryptamine.  相似文献   
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