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Leonardo Jönck Staub Roberta Rodolfo Mazzali Biscaro Erikson Kaszubowski Rosemeri Maurici 《The Journal of emergency medicine》2019,56(1):53-69
Background
Lung ultrasound can accelerate the diagnosis of life-threatening diseases in adults with respiratory symptoms.Objective
Systematically review the accuracy of lung ultrasonography (LUS) for emergency diagnosis of pneumonia, acute heart failure, and exacerbation of chronic obstructive pulmonary disease (COPD)/asthma in adults.Methods
PubMed, Embase, Scopus, Web of Science, and LILACS (Literatura Latino Americana e do Caribe em Ciências da Saúde; until 2016) were searched for prospective diagnostic accuracy studies. Rutter-Gatsonis hierarchical summary receiver operating characteristic method was used to measure the overall accuracy of LUS and Reitsma bivariate model to measure the accuracy of the different sonographic signs. This review was previously registered in PROSPERO (Centre for Reviews and Dissemination, University of York, York, UK; CRD42016048085).Results
Twenty-five studies were included: 14 assessing pneumonia, 14 assessing acute heart failure, and four assessing exacerbations of COPD/asthma. The area under the summary receiver operating characteristic curve of LUS was 0.948 for pneumonia, 0.914 for acute heart failure, and 0.906 for exacerbations of COPD/asthma. In patients suspected to have pneumonia, consolidation had sensitivity of 0.82 (95% confidence interval [CI] 0.74–0.88) and specificity of 0.94 (95% CI 0.85–0.98) for this disease. In acutely dyspneic patients, modified diffuse interstitial syndrome had sensitivity of 0.90 (95% CI 0.87–0.93) and specificity of 0.93 (95% CI 0.91–0.95) for acute heart failure, whereas B-profile had sensitivity of 0.93 (95% CI 0.72–0.98) and specificity of 0.92 (95% CI 0.79–0.97) for this disease in patients with respiratory failure. In patients with acute dyspnea or respiratory failure, the A-profile without PLAPS (posterior-lateral alveolar pleural syndrome) had sensitivity of 0.78 (95% CI 0.67–0.86) and specificity of 0.94 (95% CI 0.89–0.97) for exacerbations of COPD/asthma.Conclusion
Lung ultrasound is an accurate tool for the emergency diagnosis of pneumonia, acute heart failure, and exacerbations of COPD/asthma. 相似文献3.
To determine if impaired energy metabolism might contribute to some aspects of Alzheimer disease (AD), including the vulnerability of the CA1 region of the hippocampal formation and the altered cytoskeleton evident in neurofibrillary tangles, we examined the effects of metabolic poisons on neuronal damage and cytoskeletal disruption in the hippocampal formation. Intrahippocampal injection of 3-nitropropionic acid (3-NP) and malonic acid resulted in neuronal death, particularly in CA1. Cytoskeletal disruption included loss of dendritic MAP2, but sparing of axonal τ. MK-801 (a noncompetitive NMDA receptor antagonist) did not atenuate the lesions produced by intrahippocampal injection of malonate. MK-801, however, was effective against intrastriatal malonate. Acute systemic 3-NP resulted in neuronal damage and cytoskeletal disruption in the CA1 region of the hippocampal formation, including an extensive loss of MAP2 immuno-reactivity, but sparing of τ. The neuronal loss in CA1 was delayed as compared to striatum. Chronic intraventricular infusion of 3-NP produced a different pattern of neuronal damage. Loss of τ-1 immuno-reactivity was observed in CA3 and CA1 s. oriens, whereas MAP2 immunostaining was preserved. These results demonstrate that chronic and acute administration of metabolic inhibitors produce distinct patterns of neuronal damage and cytoskeletal disruption. The results further suggest a differential involvement of the NMDA receptor in malonate-induced neuronal damage in striatum as compared to the hippocampus. The pattern of neuronal damage and cytoskeletal disruption observed following acute metabolic impairment resembled some aspects of neurofibrillary pathology in AD, but did not result in τ hyperphosphorylation. 相似文献
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R S Desowitz K K Shida L Pang G Buchbinder 《The American journal of tropical medicine and hygiene》1989,41(6):630-634
This study characterizes a Plasmodium berghei white rat model of P. falciparum malaria in the pregnant human. Seventy-day-old and 114-day-old female rats, given an infecting inoculum at time of mating, had higher parasitemias and a more severe anemia than age- and sex-matched controls. Under these experimental conditions, the parasitemia went to crisis in all animals and there were no fatal infections. In contrast, all animals died when the infection was initiated 7 days after conception, a timing that brought a coincidence of peak parasitemia and term. Pregnancy during the post-crisis subpatent period did not cause recrudescence. At the time of delivery, the parasitemia was consistently higher in the placental (crush smear) blood than in the peripheral (tail) blood. This difference was greatest in animals giving birth shortly before or 1-2 days after the parasitemic crisis. Very young, compact parasite forms predominated in the placental blood, whereas trophozoites predominated in the peripheral blood. 相似文献
5.
赤芍总苷对沙土鼠全脑缺血再灌注损伤的保护作用 总被引:3,自引:0,他引:3
OBJECTIVE: To study the protective effects of the total paeony glycoside (TPG) against global cerebral ischemia-reperfusion injury in gerbils. METHODS: Gerbils models of global cerebral ischemia-reperfusion injury were prepared by bilateral common carotid artery ligation for 12 min followed by 24-hour reperfusion. The effects of TGP on brain edema index, superoxide dismatase (SOD) activity and malonaldehyde (MDA) concentration of the cerebral tissue homogenate and pathology of the brain were examined 24 h after model establishment. RESULTS: Compared with the model group, TPG at the doses of 200 and 400 mg/kg could significantly relieve brain edema, enhance SOD activity and lower MDA concentration in the gerbils. Pathological examination showed that the gerbils with TPG treatment had milder injury of the cells in the hippocampal CA1 region. CONCLUSIONS: TPG has obvious protective effects against global cerebral ischemia-reperfusion injury. 相似文献
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Effects of vasodilator drugs on venous tone in conscious rats 总被引:1,自引:0,他引:1
The dose-response effects of vasodilator drugs, nitroglycerin, sodium nitroprusside and hydralazine, on mean arterial pressure (MAP) and mean circulatory filling pressure (MCFP), an index of body venous tone, were investigated in conscious, unrestrained, intact rats as well as in rats treated with the ganglionic blocker, hexamethonium. The effects of these drugs were compared with those of the vehicle, normal saline, in control rats. In intact rats, i.v. infusion of nitroglycerin did not alter MAP while i.v. infusions of nitroprusside or hydralazine caused dose-dependent decreases in MAP. After ganglionic blockade, all three drugs decreased MAP. In intact rats, nitroglycerin and sodium nitroprusside did not affect MCFP but hydralazine increased MCFP. After treatment with hexamethonium, all three drugs decreased MCFP. The decreases in MCFP caused by nitroglycerin and nitroprusside, but not that by hydralazine, were significantly greater than the corresponding changes in control rats. Thus, in intact rats, the direct venodilator actions of nitroprusside and nitroglycerin were masked by endogenous sympathetic tone. When sympathetic nerve activity was attenuated, both nitroprusside and nitroglycerin have venodilator effects. Hydralazine, on the other hand, had insignificant venodilator effect both in the presence and absence of sympathetic reflexes. 相似文献
8.
Traumatic cervical Brown-Sequard and Brown-Sequard-plus syndromes: the spectrum of presentations and outcomes. 总被引:1,自引:0,他引:1
Brown-Sequard syndrome (BSS) and Brown-Sequard-plus syndrome (BSPS) are characterised by asymmetrical paresis with hypalgesia more marked on the less paretic side. This study examined the clinical features of 38 patients (30 males and 8 females; mean age = 32 years) with traumatic cervical BSS or BSPS who underwent comprehensive inpatient rehabilitation. Twenty two injuries were caused by road traffic accidents, 8 by penetrating injuries, 5 by diving injuries, and 3 by other causes. After an average of 35 days in acute care and 79 days in rehabilitation, 37 patients had increased muscle strength, all 38 patients improved functional abilities, 29 patients walked independently, 34 had spontaneous bladder emptying, 36 were discharged home, and 14 were employed. Statistically significant increases (p less than 0.001) were made in modified Barthel index functional scores between admission and discharge. Patients with BSPS had a better prognosis than did those with 'pure' BSS. Patients with predominant upper limb weakness had more favourable outcomes than did those with predominant lower limb weakness. Few other potentially predictive demographic, injury, or neurological factors were associated with functional outcome. Patients with BSS or BSPS generally have a good prognosis for neurological and functional improvement. 相似文献
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