What is the recommended tidal volume in mL/kg for patients with severe asthma?

In patients with severe asthma, the recommended tidal volume is typically lower, around 4 mL/kg. This is because individuals with severe asthma often exhibit increased airway resistance and can be at risk for barotrauma and overdistension of lung units. A lower tidal volume helps to minimize these risks while still providing adequate ventilation. This strategy also aims to enhance comfort, reduce the potential for respiratory acidosis, and allow for better management across the ventilation cycle.

Using a tidal volume of 4 mL/kg in this context is also aligned with the concept of lung-protective ventilation, which is particularly crucial in patients who may have hyperinflation or altered lung compliance. Higher tidal volumes, such as 6 mL/kg, 8 mL/kg, or 10 mL/kg, could potentially exacerbate these conditions and lead to complications. Thus, in managing severe asthma, a tidal volume of 4 mL/kg is optimal to ensure safe and effective mechanical ventilation.