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The Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM) is widely used to predict surgical complications affecting various organs. However, there are few reports about objective evaluation methods for head and neck surgery. In this study, we retrospectively examined the association between POSSUM score and actual surgical complications of head and neck reconstruction surgery. In total, 711 patients who underwent head and neck reconstruction after cancer extirpation between January 2007 and January 2015 were studied. The predicted risk of complications was calculated using the POSSUM score and compared with the actual rate of perioperative complications. Perioperative complications occurred in 178 (25%) patients, comprising systemic complications in 52 (7%) patients, surgical site infection of the head and neck area in 78 (11%) patients and failure of the free flap in 55 (8.8%) patients. When patients were divided into a perioperative complication group and a no-complication group, a significant difference between the two groups was observed in the predicted postoperative rate calculated from the POSSUM score (p?相似文献   
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Coronary artery spasm (CAS) rarely worsens from single-vessel to simultaneous multivessel CAS naturally, and simultaneous multivessel CAS leads to serious conditions such as cardiopulmonary arrest (CPA). A 77-year-old Japanese man who took medications for CAS was transferred to our hospital due to persistent chest pain. On arrival, his vital signs were stable, but his electrocardiogram (ECG) showed ST-segment elevation in leads II, III and aVF. Ventricular fibrillation developed suddenly. Although routine cardiopulmonary resuscitation (CPR) including intravenous administration of epinephrine was performed immediately, he could not be resuscitated. After initiation of percutaneous cardiopulmonary support (PCPS), there was a return of spontaneous circulation. His ECG showed exacerbation of myocardial ischemia with ST-segment elevation in leads I, II, III, aVL, aVF and V3–V6. Emergency coronary angiography revealed severe CAS of the right and left coronary arteries, which was relieved completely by intracoronary administration of nitrates. He was diagnosed with acute myocardial infarction due to simultaneous 3-vessel CAS that progressed over time. About 6 h after arrival, he developed hemodynamic instability and died. CAS worsened from single-vessel to simultaneous 3-vessel spasm, and intracoronary administration of nitrates was effective in relieving CAS, which was documented by the ECG and coronary angiogram. Since CAS can progress over time, nitrates must be administered immediately. When CAS leads to CPA, epinephrine may be ineffective in CPR because of its vasoconstrictive effect on coronary arteries; therefore, PCPS should be initiated, and intracoronary nitrates should be administered.  相似文献   
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Background: Growing evidence indicates that toxicity of fine particulate matter ≤ 2.5 μm in diameter (PM2.5) differs by chemical component. Exposure to components may differ by population.Objectives: We investigated whether exposures to PM2.5 components differ by race/ethnicity, age, and socioeconomic status (SES).Methods: Long-term exposures (2000 through 2006) were estimated for 215 U.S. census tracts for PM2.5 and for 14 PM2.5 components. Population-weighted exposures were combined to generate overall estimated exposures by race/ethnicity, education, poverty status, employment, age, and earnings. We compared population characteristics for tracts with and without PM2.5 component monitors.Results: Larger disparities in estimated exposures were observed for components than for PM2.5 total mass. For race/ethnicity, whites generally had the lowest exposures. Non-Hispanic blacks had higher exposures than did whites for 13 of the 14 components. Hispanics generally had the highest exposures (e.g., 152% higher than whites for chlorine, 94% higher for aluminum). Young persons (0–19 years of age) had levels as high as or higher than other ages for all exposures except sulfate. Persons with lower SES had higher estimated exposures, with some exceptions. For example, a 10% increase in the proportion unemployed was associated with a 20.0% increase in vanadium and an 18.3% increase in elemental carbon. Census tracts with monitors had more non-Hispanic blacks, lower education and earnings, and higher unemployment and poverty than did tracts without monitors.Conclusions: Exposures to PM2.5 components differed by race/ethnicity, age, and SES. If some components are more toxic than others, certain populations are likely to suffer higher health burdens. Demographics differed between populations covered and not covered by monitors.  相似文献   
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