In severe asthma exacerbations, what is a common acid-base abnormality?

In severe asthma exacerbations, respiratory acidosis due to CO2 retention is a common acid-base abnormality that occurs as a result of inadequate ventilation. As asthma exacerbates, the airways become significantly obstructed, leading to difficulty in exhaling carbon dioxide. Over time, when CO2 is retained, it combines with water in the body to form carbonic acid, increasing the acidity of the blood and resulting in a decline in blood pH.

This situation often progresses to respiratory acidosis, especially when the exacerbation is severe and not effectively treated. Initially, there may be periods of hyperventilation where the patient may try to compensate for the obstruction by breathing faster, potentially leading to respiratory alkalosis. However, as the exacerbation continues and the patient becomes fatigued and is unable to maintain adequate ventilation, the accumulation of CO2 takes precedence, solidifying the diagnosis of respiratory acidosis.

Recognizing these patterns is crucial in managing severe asthma exacerbations and guiding appropriate interventions to improve ventilation and address the underlying inflammation and airway obstruction.