In pregnancy, the asthmatic has several added features to bewilder and confound the intensivist. It is actually the most common condition to complicate pregnancy. The main problem is that ventilation is going to be impaired by the gravid uterus as well as by the high airway resistance (i.e. there will be a horrible combination of poor compliance and high airway resistance). Many of the drugs used to combat asthma may be either contraindicated (eg. sustained neuromuscular blockade) or counterproductive (β-agonists). Hypercapnea, tolerated as a necessary evil in the non-pregnant population, can have a disastrous effect on the acid-base balance of the foetus. In short, everything is more complicated.
This topic has come up before, in Question 18 from the first paper of 2009. The college wanted us to "outline the challenges specifically associated with the management of a pregnant patient with status asthmaticus". An ideal single best reference for this topic would have to be either the 2005 article by Hanania et al or the more recent (2014) paper by Chan et al. The trainee in advanced stages of last-minute revision is also directed to the LITFL article on this topic.
The main issues are:
Usually, there is no reason to perform a caesarian. However, strangely, delivery seems to improve the status asthmaticus - at least in case reports. certainly, one would not think twice about it if CPR is in progress.