Final answer:
During an acute asthma attack, retractions occur when the chest sucks in above the stomach due to the extra effort needed to breathe. This is a sign of severe asthma requiring immediate treatment, which may include the use of inhalers or other medications to relax the airway muscles.
Step-by-step explanation:
The nurse's most accurate response to the mother's question about why the child's chest is 'sucking in' above the stomach during an acute asthma attack would be to explain that this is due to a phenomenon called retractions. Retractions are a sign that the person is working harder to breathe. In the case of an asthma attack, the airways are narrowed due to inflammation and constriction which makes it harder to move air in and out of the lungs. As a result, the muscles between the ribs and other muscles in the upper chest have to work harder to help expand the chest for breathing, which can cause the skin around the ribs and above the stomach to suck inwards, or retract.
Seeing retractions is an indication that the asthma attack is severe and that immediate medical intervention is necessary to open up the airways and improve breathing. Inhalers or other bronchodilators are commonly used to treat asthma symptoms by relaxing the muscles around the airways, allowing for better airflow.