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Context

Survival predictions for advanced cancer patients impact many aspects of care, but the accuracy of clinician prediction of survival (CPS) is low. Prognostic tools such as the Palliative Prognostic Index (PPI) have been proposed to improve accuracy of predictions. However, it is not known if PPI is better than CPS at discriminating survival.

Objective

We compared the prognostic accuracy of CPS to PPI in patients with advanced cancer.

Methods

This was a prospective study in which palliative care physicians at our tertiary care cancer center documented both the PPI and CPS in hospitalized patients with advanced cancer. We compared the discrimination of CPS and PPI using concordance statistics, area under the receiver-operating characteristics curve (AUC), net reclassification index, and integrated discrimination improvement for 30-day survival and 100-day survival.

Results

Two hundred fifteen patients were enrolled with a median survival of 109 days and a median follow-up of 239 days. The AUC for 30-day survival was 0.76 (95% CI 0.66–0.85) for PPI and 0.58 (95% CI 0.47–0.68) for CPS (P < 0.0001). Using the net reclassification index, 67% of patients were correctly reclassified using PPI instead of CPS for 30-day survival (P = 0.0005). CPS and PPI had similar accuracy for 100-day survival (AUC 0.62 vs. 0.64; P = 0.58).

Conclusion

We found that PPI was more accurate than CPS when used to discriminate survival at 30 days, but not at 100 days. This study highlights the reason and timing for using PPI to facilitate survival predictions.  相似文献   
64.
OBJECTIVE: To compare the findings of the Useful Field of View (UFOV) test with those of conventional neuropsychologic tests to determine the utility of the UFOV test as a measure of attention in a population with brain injury. DESIGN: Cohort study. SETTING: Freestanding rehabilitation hospital. PARTICIPANTS: Fifteen inpatients with severe brain injury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: UFOV test, FIM\T instrument, length of stay (LOS), and standard neuropsychologic testing. RESULTS: The UFOV subtest UF2 correlated strongly with the other 2 subtests, UF1 and UF3. The UF2 subtest correlated most strongly with paper and pencil tests of visual attention. The UF2 predicted 52% of the FIM change and 60% of the LOS variance, second only to admission FIM score, which predicted 75% and 80% of FIM change and LOS variance, respectively. CONCLUSIONS: Among the patients in our study, the UFOV test can be used to determine the visual divided attention of patients with acquired brain injury. The results also showed that the UFOV test correlated with LOS and FIM change in patients with acquired brain injury recovering in a rehabilitation facility. Because the UFOV test is much more quickly administered and scored than other measures of attention and divided attention, these results suggest that the UFOV test may provide an easy means to measure a critical variable in the population with head injury.  相似文献   
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Long-term exposure to the oxidant air pollutant ozone (O(3)) is associated with tolerance to the acute effects of oxidant injury. To test whether this resistance to acute injury extends to bioactivated pulmonary toxicants, male Sprague-Dawley rats were exposed to filtered air (FA) or 0.8 ppm O(3) (8 h/day) for 90 days and administered 1-nitronaphthalene i.p. at doses of 0, 50, or 100 mg/kg. 1-Nitronaphthalene is a pulmonary cytotoxicant requiring metabolic activation. High-resolution histopathology, transmission electron microscopy, and morphometry revealed significantly greater 1-nitronaphthalene toxicity in the central acinar region of O(3)- compared with FA-exposed rats. At 100 mg/kg, injury to terminal bronchioles in O(3)-exposed rats involved denudation of 86% of the basement membrane; 78% of the cells remaining on the epithelium were necrotic. This is compared with denudation of 4% of the basement membrane of FA-exposed rats administered 100 mg/kg 1-nitronaphthalene; only 25% of the cells remaining on the epithelium were necrotic. The key difference between FA- and O(3)-exposed rats treated with 1-nitronaphthalene was the heightened severity of ciliated cell toxicity in O(3)-exposed animals. This is despite the fact that long-term exposure to ozone produces tolerance to oxidant stress in the epithelium of the central acinus. No differences in the susceptibility of intrapulmonary airways or trachea to 1-nitronaphthalene were observed between filtered air- and ozone-exposed rats. This study demonstrates a site-selective synergy between the copollutants ozone and 1-nitronaphthalene in the production of acute lung injury.  相似文献   
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Numerous studies show an association between particulate air pollution and adverse health effects. Particulate matter is a complex mixture of elemental carbon, ammonium, sulfates, nitrates, organic components, and metals. The mechanisms of action of particulate matter less than or equal to 2.5 micro m in mean aerodynamic diameter (PM(2.5)), as well as the constituents responsible for the observed cardiopulmonary health effects, have not been identified. In this study we focused on the association between the metallic component of PM(2.5) and cardiac autonomic function based on standard heart rate variability (HRV) measures in an epidemiologic study of boilermakers. Thirty-nine male boilermakers were monitored throughout a work shift. Each subject wore an ambulatory electrocardiogram (Holter) monitor and a personal monitor to measure PM(2.5). We used mixed-effects models to regress heart rate and SDNN index (standard deviation of the normal-to-normal) on PM(2.5) and six metals (vanadium, nickel, chromium, lead, copper, and manganese). There were statistically significant mean increases in the SDNN index of 11.30 msec and 3.98 msec for every 1 micro g/m(3) increase in the lead and vanadium concentrations, respectively, after adjusting for mean heart rate, age, and smoking status. Small changes in mean heart rate were seen with all exposure metrics. The results of this study suggest an association between exposure to airborne metals and significant alterations in cardiac autonomic function. These results extend our understanding of the adverse health effects of the metals component of ambient PM(2.5).  相似文献   
70.
Modern concepts of treatment and prevention of lightning injuries   总被引:3,自引:0,他引:3  
Lightning is the second most common cause of weather-related death in the United States. Lightning is a natural atmospheric discharge that occurs between regions of net positive and net negative electric charges. There are several types of lightning, including streak lightning, sheet lightning, ribbon lightning, bead lightning, and ball lightning. Lightning causes injury through five basic mechanisms: direct strike, flash discharge (splash), contact, ground current (step voltage), and blunt trauma. While persons struck by lightning show evidence of multisystem derangement, the most dramatic effects involve the cardiovascular and central nervous systems. Cardiopulmonary arrest is the most common cause of death in lightning victims. Immediate resuscitation of people struck by lightning greatly affects the prognosis. Electrocardiographic changes observed following lightning accidents are probably from primary electric injury or burns of the myocardium without coronary artery occlusion. Lightning induces vasomotor spasm from direct sympathetic stimulation resulting in severe loss of pulses in the extremities. This vasoconstriction may be associated with transient paralysis. Damage to the central nervous system accounts for the second most debilitating group of injuries. Central nervous system injuries from lightning include amnesia and confusion, immediate loss of consciousness, weakness, intracranial injuries, and even brief aphasia. Other organ systems injured by lightning include the eye, ear, gastrointestinal system, skin, and musculoskeletal system. The best treatment of lightning injuries is prevention. The Lightning Safety Guidelines devised by the Lightning Safety Group should be instituted in the United States and other nations to prevent these devastating injuries.  相似文献   
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