Ventilation In Acute Asthma Research Articles

Case report: emergency treatment of near-fatal acute asthma

Asthma is a chronic inflammatory disease affecting small airways, associated with hyperresponsiveness, reversible airflow-limitation and respiratory symptoms. During exhacerbations, the symptoms severity may vary from mild dyspnea to fatal status asthmaticus. Non-invasive ventilation is a respiratory support method that in COPD has been used succesfully in the last 20 years; there is an increasingly interest about using non-invasive ventilation also in asthmatic patients. However, its role in status asthmaticus has not been yet established. In this article we report a case of a patient succesfully treated with non-invasive ventilation and we also review the literature about non-invasive ventilation in acute asthma

Hypoventilation in Asthma and Chronic Obstructive Pulmonary Disease

Chronic hypoventilation is a marker of disease severity in asthma and chronic obstructive pulmonary disease (COPD). The degree to which this predicts severity or objective measures of lung function is variable, and more reliable for COPD than for asthma. Patients with COPD are particularly susceptible to nocturnal hypoventilation, but at-risk patients can be identified by abnormalities in daytime gas exchange. Continuous positive airway pressure and noninvasive ventilation have no demonstrated efficacy in the treatment of chronic hypoventilation solely due to asthma or COPD. There is consensus that early treatment with noninvasive ventilation for acute hypoventilation due to a COPD exacerbation is not only highly effective, but it reduces mortality, the need for endotracheal intubation, and hospital length of stay. There is probable benefit to the use of noninvasive ventilation in acute asthma, but the evidence to support this is far less robust than for COPD.

Concordance Between Capnography and Arterial Blood Gas Measurements of Carbon Dioxide in Acute Asthma

We examine the concordance between end-tidal partial pressure of CO2 (PetCO2) measured by capnography and arterial partial pressure of carbon dioxide (PaCO2) obtained by arterial blood gas in acute asthmatic patients presenting to the emergency department. This was a prospective observational cohort study of acutely ill adult asthmatic patients undergoing an arterial blood gas measurement as part of their evaluation. PetCO2 was recorded during exhalation into a capnograph while arterial blood was pulsing in the arterial blood gas tubing. Concordance between PetCO2 and PaCO2 was displayed as a Bland-Altman matrix, using prespecified limits of agreement of +/-5 mm Hg difference between PetCO2 and PaCO2 in each patient. The mean difference between the PetCO2 and PaCO2 levels was 1.0 mm Hg (95% confidence interval -0.1 to 2.0 mm Hg), with a median of 0 mm Hg. Of the 39 patients enrolled, 37 (95%) fell within the a priori limits of agreement. In adult asthmatic patients with acute exacerbations, concordance between PetCO2 measured by capnography and PaCO2 measured by arterial blood gas was high. These findings must be validated before capnography replacement of arterial blood gas as an accurate means of assessing alveolar ventilation in acute asthma is recommended.