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Coagulation changes and edema formation during long-distance bus travel.   总被引:4,自引:0,他引:4  
Long-distance travel in a cramped position by aircraft or by bus and car has been suggested to be associated with an increased risk for thromboembolic events. Recently, we demonstrated moderate activation of coagulation after a long-haul flight. At present the single contributing factors (i.e. hypoxia and low humidity on board an aircraft and prolonged sitting in an aircraft, car or bus inducing venous stasis) have not yet been investigated. Therefore we measured markers of coagulation and fibrinolysis as well as functional parameters of coagulation using activated thrombelastography in 19 healthy volunteers before, during and after a real 10-h bus journey. In addition, changes in leg volume were measured. Thrombelastography revealed moderate activation of coagulation in all travelers, which was accompanied by a significant increase in prothrombin fragment F1 + 2. Thrombin-antithrombin III complexes and D-dimer remained unchanged, and tissue-type plasminogen activator and plasminogen-activator inhibitor 1 decreased after travel. After the travel we found a significant increase in leg volume that was exclusively distributed in the calf. We conclude that beside long-haul flights also long-distance bus travel induces a certain activation of the coagulation system. Thus, it is questionable whether hypoxia is the crucial risk factor for thromboembolic events after long-haul flights.  相似文献   
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BACKGROUND: A multicenter intercomparison assessment was made of the variation in left ventricular (LV) volumes and ejection fractions (EFs) obtained from gated myocardial perfusion single photon emission computed tomography (SPECT) of the 3-dimensional AGATE (Amsterdam gated) cardiac phantom. METHODS AND RESULTS: The phantom was configured to produce 3 different standard end-systolic volume and end-diastolic volume combinations (50 mL and 120 mL, 90 mL and 160 mL, and 120 mL and 190 mL) with corresponding EF (58%, 44%, and 37%). Quantitative gated myocardial perfusion SPECT was performed with 39 SPECT systems in 35 departments. In the multicenter study, for all 3 filling conditions, a wide range of results was obtained. The EF was overestimated (by 1% to 15%), and both the end-systolic volume and end-diastolic volume were underestimated (by 1 to 65 mL). The extent of overestimation of EF was related to the extent of underestimation of the volumes and was independent of filling condition. The trend in error per center was comparable for all 3 filling conditions. Acquisition time per projection was the only independent predictor of the difference between measured and expected EF (P = .0001). CONCLUSIONS: Care should be taken before extrapolation of published and accepted cutoff values for LV EF and volumes in clinical decision making. Results should be validated in each center and monitored for accuracy and consistency over time.  相似文献   
145.
Eichler P  Lubenow N  Strobel U  Greinacher A 《Blood》2004,103(2):613-616
Bivalirudin is a synthetic antithrombin sharing a sequence of 11 amino acids with the recombinant hirudin lepirudin. We investigated whether antilepirudin antibodies recognize epitopes on bivalirudin. Antilepirudin antibody-positive sera of 43 patients, treated with lepirudin for heparin-induced thrombocytopenia, were analyzed. Lepirudin- and bivalirudin-coated microtiter plates were used for antibody testing in an enzyme-linked immunosorbent assay (ELISA) system. Of the 43 sera-containing antibodies binding to lepirudin, 22 (51.2%) contained antibodies that also recognized bivalirudin. Binding of these antibodies to bivalirudin was inhibited by more than 70% by preincubation with high doses of bivalirudin. However, if lepirudin-coated microtiter plates were used, high concentrations of bivalirudin inhibited only 2 of the 43 positive sera by more than 30%. Therefore antihirudin antibodies must be polyspecific. The clinical consequences of this cross-reactivity are unknown but bivalirudin, targeted by antibodies of patients treated with lepirudin previously, could potentially boost antibody titers in such patients or even trigger an immune response by itself. Clinically significant antibody formation in response to bivalirudin monotherapy has not been observed, however. Yet, as lepirudin and antilepirudin antibodies have recently been implicated in severe anaphylactic reactions, caution is warranted when using bivalirudin in patients previously treated with lepirudin.  相似文献   
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This report compares the cumulative efficacy of cardioversion and skeletal muscle injury after either damped sine wave monophasic or truncated exponential biphasic transthoracic cardioversion of persistent atrial fibrillation. The trial sought to refute the null hypothesis of therapeutic equivalence between monophasic and biphasic waveforms. Results of the study reveal similar cumulative efficacy of waveforms and greater levels of skeletal muscle damage when patients are younger and male, and when monophasic waveforms are used.  相似文献   
149.
Objective: Prolonged-release oxycodone/naloxone (OXN PR) showed improved gastrointestinal tolerability and equivalent analgesic efficacy compared to oxycodone alone in patients with non-cancer pain or cancer pain. This is the first dataset to demonstrate its effectiveness and safety compared to other strong opioids in opioid-naïve patients.

Methods: This is a subgroup analysis of a 4- to 6-week multicenter, observational study. A total of 162 opioid-naïve patients with moderate-to-severe pain of varying etiologies received either OXN PR or other strong opioids (control group). Documented parameters include pain relief (numeric rating scale), bowel function (Bowel Function Index [BFI]), pain-related functional impairment (Brief Pain Inventory Short Form), quality of life (QoL; EuroQol EQ-5D-3L) and a global therapy assessment.

Results: OXN group patients experienced a substantial clinically important reduction in mean pain intensity of 51.4%, compared to a 28.6% reduction in control patients. Although the BFI remained in the reference range in both groups, there was a difference between BFI changes during treatment in favor of OXN PR. The superior effectiveness of OXN PR was paralleled by greater improvements of pain interference and QoL and fewer adverse drug reactions compared to other strong opioids.

Conclusion: The favorable outcomes under real-life conditions suggest that OXN PR provides a valuable option for treatment of moderate-to-severe pain without using weak opioids first.  相似文献   

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