Flight nurse, ground paramedic
My understanding (and of course, I could be wrong) is that mag isn't really useful for COPD, only asthma (due to the fact that in COPD, the damage/constriction is chronic. In asthma, the constriction is more acute, thus responds better to mag).My last round of research on this topic revealed that CPAP -MAY- help in COPD exacerbation but the exact physiology behind why it works was still unclear.
What I train our folks here is this;
CPAP may be an intermediate step before intubation in COPD patients, but you need to be ready and willing to move on if it doesn't help (pre-plan you drugs, stage your equipment, and assess the airway difficulty). Anecdotally here - mag sulfate infusions seem to do a better job of turning these folks around than CPAP, and I think the majority of our department has shifted in that direction as the intermediate step before RSI.
I've only initiated CPAP once prehospitally on a COPD patient, and I can say that the improvement was drastic on just 5 of PEEP. Went from gasping to sleeping/resting (not the "oh crap" resting of a respiratory patient, a legitimate "oh, they look comfortable!").