What is the most reassuring sign of effective treatment for a patient with an acute asthma attack?

The most reassuring sign of effective treatment for a patient experiencing an acute asthma attack is when the peak expiratory flow (PEF) returns to personal best levels. This measurement indicates that the patient's airflow has significantly improved and is close to their baseline status before the asthma exacerbation. Achieving personal best PEF levels suggests that the airways are opening up effectively in response to treatment, allowing for better air movement and improved oxygenation.

Monitoring PEF is crucial because it quantifies the severity of airway obstruction. When patients return to their baseline levels, it reflects that they are regaining control over their asthma symptoms. It is a clear and objective sign indicating that the treatment regimen is working effectively.

While a decrease in respiratory rate, a normal pulse rate, and a reduction in wheezing are also positive indicators, they might not be as definitive on their own. For instance, a respiratory rate may still be elevated due to anxiety or other factors despite effective treatment. A normal pulse rate can occur even if there is still significant airway obstruction. Similarly, wheezing can continue even when airflow variability is improving. Therefore, returning PEF to personal best levels stands out as the most assuring sign of effective treatment.