Dyspnea and Biomarkers in a Prehospital Setting

Study Overview
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Brief Summary
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In patients presenting with acute dyspnea in a pre-hospital setting, the early and correct diagnosis may present a significant clinical challenge. Physical examination, chest radiography, electrocardiography, and standard biological tests often fail to accurately differentiate heart failure (HF) from pulmonary causes of dyspnea. Timely differentiation of HF from other causes of dyspnea may permit the early institution of appropriate medical therapy. Brain natriuretic peptide (BNP) and amino-terminal pro-brain natriuretic peptide (NT-proBNP) have been proposed as early markers of HF and demonstrated to be useful for diagnosing and excluding HF in the emergency department. A combination of BNP or NT-proBNP testing and standard clinical assessment has been suggested to be superior to either tool used in isolation. Some previous studies have also suggested that quantitative capnometry (QC) may be useful in differentiating between cardiac and obstructive causes of respiratory distress. Therefore, the investigators hypothesized that a new combination of NT-proBNP testing, standard clinical assessment, and partial pressure of end-tidal CO2 (PetCO2) would optimize evaluation and differentiation of acute dyspnea in a pre-hospital setting. The aim of this study was to determine the accuracy of combination of QC, NT-proBNP, and clinical assessment in differentiating acute HF from obstructive pulmonary disease (COPD/asthma) as a cause of acute dyspnea in pre-hospital emergency setting.

Official Title
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Quantitative Capnometry and Nt-proBNP in Differentiating of Acute Dyspnea in Pre-Hospital Emergency Setting

Conditions
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Dyspnea, Heart Failure, Asthma, COPD

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient had to present with shortness of breath as the primary complaint (defined as either the sudden onset of dyspnea without history of chronic dyspnea or an increase in the severity of chronic dyspnea) Exclusion Criteria: age <18 years history of renal insufficiency, trauma, severe coronary ischemia (unless patient's predominant presentation was dyspnea), and other causes of dyspnea: pneumonia pulmonary embolism carcinoma pneumothorax pleural effusion intoxications (drugs) anaphylactic reactions upper airway obstruction bronchial stenosis gastroesophageal reflux disorder according to the history, clinical status, and additional laboratory tests available in pre-hospital setting (D-dimer, troponin, C-reactive protein)
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Group with obstructive causes of dyspnea<br>Criteria for clinical assessment of severe asthma (diffuse polyphonic bilateral and particular expiratory wheezes, chest tightness, shortness of breath, using accessory muscles of breathing, signs of hyperinflation, atopic condition, personal or family history of asthma, tachypnea, previous asthma and asthma medications, and the value of modified Boston criteria for HF ≤ 5) and criteria for chronic obstructive pulmonary disease (COPD) exacerbation (history of COPD, COPD medications, cough, worsening dyspnea, increased sputum production and volume, increased sputum purulence, rhonchi and rales, modified Boston criteria for HF ≤ 5) | |
| Heart failure group<br>The investigators protocol for clinical assessment of HF-related acute dyspnea (the prehospital clinical assessment for HF) was designed based on Boston (13) and Framingham criteria for HF (14) (Table 1). The investigators did not use certain criteria from the original protocols, which were not available in the prehospital setting (e.g., chest radiography). | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Quantitative Capnometry, N-Terminal Pro-Brain Natriuretic Peptide, Acute Heart Failure, Diagnostic Accuracy