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971.
972.
Endotracheal intubation is required in 5–10% of all prehospital emergencies. Poor environmental conditions (e.g. limited space, poor or excessive lighting etc.), unfavorable patient-related factors (e.g. trauma, bleeding, pulmonary aspiration etc.) and the pressure of time make prehospital airway management a challenging procedure even for experienced emergency physicians. The incidence of difficult endotracheal intubation is significantly higher than in-hospital. Profound clinical practice, recognition and adequate treatment of complications of intubation, and ongoing clinical practice are essential for successful and responsible prehospital airway management. A brief physical examination helps to identify predictors for difficult intubation, thereby modifying treatment strategies. Every emergency physician must be closely familiar with at least one supraglottic airway device and the recent algorithms to manage the unanticipated difficult airway.  相似文献   
973.
974.
Background: Primary afferent nociceptor sensitization and its accompanying spontaneous discharge are believed to be the proximate cause of the spontaneous pain and hypersensitivity that follow an acute tissue injury. Evidence for this comes almost entirely from studies limited to the first few minutes to an hour or two after injury, when the inflammatory reaction to injury has just begun. However, there is evidence that inflammatory pain mechanisms differ from acute pain mechanisms and that the mechanisms that drive and modulate inflammatory pain may evolve over time.

Methods: The authors surveyed spontaneous afferent discharge in rats with hind paw inflammation evoked by complete Freund adjuvant over the entire 14 days of the inflammatory pain condition, as determined in parallel experiments assessing allodynia and hyperalgesia.

Results: Inflammation-evoked heat hyperalgesia, mechanoallodynia, and mechanohyperalgesia began within hours, persisted until at least day 7, and resolved by day 14. A large percentage (23%) of A fibers had spontaneous discharge 2 days after inflammation, but the incidence was much reduced (to 7-9%) by 7 and 14 days. At all times, the A-fiber discharge frequency was low (<3.0 Hz) or very low (<0.3 Hz). A large percentage (24%) of C fibers had spontaneous discharge 2 and 7 days after inflammation, but this also declined to near control levels by day 14; C-fiber discharge frequency was also always low (most at 0.3-1.0 Hz).  相似文献   

975.
976.
Haemoglobin (Hb) abnormalities in chronic obstructive pulmonary disease (COPD) are not well characterised. The present authors investigated the prevalence and association of abnormal Hb with clinical outcomes. Analysis of a prospective cohort of stable COPD outpatients (n = 683) in a USA Veterans Administration pulmonary clinic was undertaken. Patients were classified as anaemic (Hb <13 g.dL(-1)), polycythemic (Hb > or =17 g.dL(-1) and > or =15 g.dL(-1) for males and females, respectively) or normal. Demographic characteristics and physiological/functional outcomes were compared between groups. Regression models adjusting for confounders examined the independent association of anaemia with clinical outcomes. Anaemia was present in 116 (17%) patients and polycythemia in 40 (6%). While the only values that differed between polycythemic and nonpolycythemic patients were mean body mass index and Hb, anaemic patients showed a significantly higher modified Medical Research Council dyspnoea scale score (2.8 versus 2.6), lower 6-min walk distance (265 versus 325 m) and shorter median survival (49 versus 74 months) than nonanaemic patients. In regression models, anaemia independently predicted dyspnoea and reduced exercise capacity. Anaemia in chronic obstructive pulmonary disease was an independent risk factor for reduced functional capacity. Polycythemia prevalence was low and had no association with worsened outcomes. Further work is required to evaluate the effect of anaemia correction on outcomes in chronic obstructive pulmonary disease.  相似文献   
977.
978.
OBJECTIVE: The aim of this study was to determine whether EEG slowing is more pronounced in older than younger OSAS patients and to verify whether this cortical slowing is correlated to daytime performance, respiratory perturbation and sleep fragmentation. METHODS: Twelve young OSAS patients (mean age 38.2+/-2.0 y) and 13 older OSAS patients (mean age 62.2+/-1.9 y) along with 13 young controls (mean age 35.8+/-2.0 y) and 14 older controls (mean age 60.2+/-2.0 y) underwent a polysomnographic evaluation followed by a waking EEG recording. As a global index of cortical slowing, a ratio of slow-to-fast frequencies was calculated in all cortical regions. Daytime performance was assessed using the four choice reaction time test. RESULTS: Differences in waking EEG and in daytime performance were analyzed by ANOVAs with Group and Age as factors. Waking EEG did not yield a Group by Age interaction. OSAS patients had higher ratios across all regions than controls. Similarly, daytime performance revealed no Group by Age interaction. However, OSAS patients showed more lapses than controls and older subjects were slower than younger subjects. CONCLUSIONS: Our results indicate that age does not interact with OSAS to worsen the severity of cortical slowing, but age can add to the OSAS effect to worsen daytime performance deficits in OSAS patients. SIGNIFICANCE: The daytime performance deficits observed particularly in elderly OSAS patients warrant a careful clinical assessment of these patients to prevent accidents and injuries.  相似文献   
979.
980.

Background  

Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.  相似文献   
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