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71.
72.
Objective: In recent years, the costs of epinephrine autoinjectors (EAIs) in the United States have risen substantially. King County Emergency Medical Services implemented the “Check and Inject” program to replace EAIs by teaching emergency medical technicians (EMTs) to manually aspirate epinephrine from a single-use 1 mg/mL epinephrine vial using a needle and syringe followed by prehospital intramuscular administration of the correct adult or pediatric dose of epinephrine for anaphylaxis or serious allergic reaction. Treatment was guided by an EMT protocol that required a trigger and symptoms. We sought to determine if the “Check and Inject” program was safely implemented by EMTs treating presumed prehospital anaphylaxis or serious allergic reaction. Methods: We conducted a prospective investigation of all cases treated as part of the “Check and Inject” program from July 2014 through December 2016 in suburban King County, Washington, and January 2016 through December 2016 within the city of Seattle. All cases were prospectively collected using a custom quality improvement data form completed by the first responding EMTs. Two physicians completed a structured review of each EMS medical record to determine if the EMTs followed the Check and Inject protocol and determine if epinephrine was clinically-indicated based on physician review. Results: Of the 411 cases eligible for analysis, EMTs followed the protocol appropriately in 367 (89.3%) cases. In the remaining 44 (10.7%) cases, the EMS incident report form failed to document either a clear inciting allergic trigger or an appropriate symptom from the protocol list. Physician review determined that epinephrine was clinically indicated in 36 of the 44 cases. Among the remaining 8 cases (1.9%) that did not meet protocol criteria and were not clinically-indicated based on physician review, none had a documented adverse reaction to the epinephrine. Conclusion: We observed that EMTs successfully implemented the manual “Check and Inject” program for severe allergic reactions and anaphylaxis in a manner that typically agreed with physician review and without any overt identified safety issues.  相似文献   
73.
Left atrium (LA) size is a well-studied predictor of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). Yet, there is still little agreement on the best imaging technique to size the LA, and on the most appropriate sizing parameter. Volumetric assessment of LA with three-dimensional rotational angiography (3DRA LA volume index) might be a valid alternative to the commonly used transthoracic echocardiography (TTE LA volume index). The aim of our study was to investigate whether LA volume by 3DRA at the time of PVI is able to predict the risk of atrial fibrillation recurrence. We analysed 352 consecutive patients with symptomatic paroxysmal or persistent atrial fibrillation referred for PVI to our Institution. In all patients, LA volume index (LAVI) was assessed by TTE and by 3DRA. Sinus rhythm was restored after PVI in 348 patients (99%). Average TTE-LAVI and 3DRA-LAVI were 37?±?12 and 83?±?18 ml/m2, respectively. At a median follow-up of 19 (12, 24) months, 27% of patients had AF recurrence after the first PVI. At the univariate analysis, persistent AF (p?<?0.01), use of anti-arrhythmic drugs (AAD) (p?<?0.05) and 3DRA-LAVI (p?<?0.01) were significantly associated with AF recurrence. In contrast, none of the echocardiographic parameters considered, including TTE-LAVI, was associated with AF recurrence (p?=?0.29). At the multivariate analysis, 3DRA-LAVI was the only independent predictor for AF recurrence (HR 1.01 [1.00–1.03], p?=?0.017). Left atrial volume measured with 3DRA is superior to TTE assessment and to AF history in predicting atrial fibrillation recurrence after PVI.  相似文献   
74.

Purpose

Diffuse remodeling of myocardial extra-cellular matrix is largely responsible for left ventricle (LV) dysfunction and arrhythmias. Our hypothesis is that the texture analysis of late iodine enhancement (LIE) cardiac computed tomography (cCT) images may improve characterization of the diffuse extra-cellular matrix changes. Our aim was to extract volumetric extracellular volume (ECV) and LIE texture features of non-scarred (remote) myocardium from cCT of patients with recurrent ventricular tachycardia (rVT), and to compare these radiomic features with LV-function, LV-remodeling, and underlying cardiac disease.

Procedures

Forty-eight patients suffering from rVT were prospectively enrolled: 5/48 with idiopathic VT (IVT), 23/48 with post-ischemic dilated cardiomyopathy (ICM), 9/48 with idiopathic dilated cardiomyopathy (IDCM), and 11/48 with scars from a previous healed myocarditis (MYO). All patients underwent echocardiography to assess LV systolic and diastolic function and cCT with pre-contrast, angiographic, and LIE scan to obtain end-diastolic volume (EDV), ECV, and first-order texture parameters of Hounsfield Unit (HU) of remote myocardium in LIE [energy, entropy, HU-mean, HU-median, standard deviation (SD), and mean absolute deviation (MAD)].

Results

Energy, HU mean, and HU median by cCT texture analysis correlated with ECV (rho?=?0.5650, rho?=?0.5741, rho?=?0.5068; p?<?0.0005). cCT-derived ECV, HU-mean, HU-median, SD, and MAD correlated directly to EDV by cCT and inversely to ejection fraction by echocardiography (p?<?0.05). SD and MAD correlated with diastolic function by echocardiography (rho?=?0.3837, p?=?0.0071; rho?=?0.3330, p?=?0.0208). MYO and IVT patients were characterized by significantly lower values of SD and MAD when compared with ICM and IDCM patients, independently of LV-volume systolic and diastolic function.

Conclusions

Texture analysis of LIE may expand cCT capability of myocardial characterization. Myocardial heterogeneity (SD and MAD) was associated with LV dilatation, systolic and diastolic function, and is able to potentially identify the different patterns of structural remodeling characterizing patients with rVT of different etiology.
  相似文献   
75.
Objective: Elevated calcium concentration is a commonly used measure in screening analyses for primary hyperparathyroidism (pHPT) and cancer. Low bone mineral density (BMD) and osteoporosis are common features of pHPT and strengthen the indication for parathyroidectomy. It is not known whether an elevated calcium concentration could be a marker of low BMD in suspected pHPT patients with a normal parathyroid hormone concentration.

Purpose: To study if low BMD and osteoporosis are more common after ten years in patients with elevated compared with normal calcium concentrations at baseline.

Design: Prospective case control study.

Setting: Primary care, southern Sweden.

Subjects: One hundred twenty-seven patients (28 men) with baseline elevated, and 254 patients (56 men) with baseline normal calcium concentrations, mean age 61 years, were recruited. After ten years, 77% of those still alive (74 with elevated and 154 with normal calcium concentrations at baseline) participated in a dual energy x-ray absorptiometry measurement for BMD assessment and analysis of calcium and parathyroid hormone concentrations.

Main outcome measures: Association between elevated and normal calcium concentration at base-line and BMD at follow-up. Correlation between calcium and parathyroid hormone concentrations and BMD at follow-up.

Results: A larger proportion of the patients with elevated baseline calcium concentrations who participated in the follow-up had osteoporosis (p value?=?0.036), compared with the patients with normal concentrations. In contrast, no correlation was found between calcium or parathyroid hormone concentrations and BMD at follow-up.

Conclusions: In this study, patients with elevated calcium concentrations at baseline had osteoporosis ten years later more often than controls (45% vs. 29%), which highlights the importance of examining these patients further using absorptiometry, even when their parathyroid hormone level is normal.
  • Key Points
  • Osteoporosis is common, difficult to detect and usually untreated. It is not known whether elevated calcium concentrations, irrespective of the PTH level, could be a marker of low bone mineral density.

  • No correlation was found between calcium or parathyroid hormone concentrations and bone mineral density at follow-up.

  • In this study, patients with elevated calcium concentrations at baseline had osteoporosis ten years later more often than controls (45% vs. 29%).

  相似文献   
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BACKGROUND: Procalcitonin (PCT) is a recently described inflammatory marker that has been shown to increase significantly in patients with severe systemic bacterial infections or sepsis. Reports on the diagnostic and predictive value of PCT in systemic fungal infections are limited. METHODS: In order to evaluate the role of PCT in systemic mycosis, 14 patients (mean age 40 years) with proven or probable systemic fungal infections were investigated. Blood samples were collected on days 1, 3, 5, and 10 after the onset of signs and symptoms of systemic fungal infection (clinical and/or laboratory diagnosis and/or radiographic evidence). PCT measurements were performed using an immunoluminometric assay. RESULTS: In five patients with severe fungal infection and an unfavorable course (patient group 2), PCT levels were moderately elevated on day 3 (0.5-1.0 ng/ml), whereas they were normal in the patients who recovered (patient group 1). High PCT levels (>/=1.11 ng/ml) were detected on the 10th day of the course of the illness in patient group 2. A normal or moderate elevation of PCT on day 10 was observed in patient group 1. The difference in mean PCT levels in patient groups 1 and 2 on days 3 and 10 were statistically significant. CONCLUSIONS: PCT levels seem to correlate with the severity and outcome of systemic fungal infection. If this finding can be confirmed in a larger number of patients, it could serve as a prognostic indicator.  相似文献   
80.
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