This post draws from a talk given by Prescott Woodruff, MD, MPH at UCSF's 17th annual hospital medicine conference.
There are numerous classifications of asthma and they overlap somewhat. A useful one for the hospital presentation of asthma is type 1 versus type 2. Type 1 is by far the most common and is mediated by inflammatory cell infiltration and mucus plugging. As such it is gradual in onset and slow to resolve. Type 2, sometimes referred to as “sudden asphyxic asthma,” has a more rapid onset but also responds more rapidly to treatment. It is characterized by intense bronchospasm and less of an inflammatory component. Review here.
Corticosteroids: Dose? Route?
High level evidence to guide clinicians is lacking. The “official” recommendation is to start with oral and switch to IV if poor response. The speaker initiates IV therapy in critically ill patients.
Levalbuterol versus albuterol
Evidence mixed, controversy unresolved. It may not matter.
Not generally recommended for asthma per se but indicated if specific signs/sx of infection e.g. fever, purulency. Don't forget sinusitis.
Forget about it.
Probably helpful as an adjunct.
No evidence that it impacts hard clinical outcomes but works fast and may buy time initially until other therapies take effect.   If FiO2 of over 40% is required it's not a good option (you can't mix in enough helium).
2 grams IV may help as an adjunct to improve pulmonary function during the initial management of severe attacks.