[Gila]

Unfortunately, autonomic and somatic cholinergic receptor physiology is a bit more complicated.

[JLP]

schuflea, on 11 February 2012 - 04:30 PM, said:

So, bronchospasm, why not paralyze her? And isn't Mag way down the algorithm for Status / obstructive airway diseases process? I would think paralytics would relax smooth muscle enough without throwing us into an arrhythmia. I would wonder if sticking with small doses of epi (for anti-inflammatory uses).

Paralytics have little to no effect on smooth muscle. Paralytics work by blocking nicotinic ACh receptors at voluntary muscle synapses, either without stimulating them (NDMB's such as roc, vec, pancuronium) or by stimulating them and then preventing them from returning to a ready state (sux). There are very few nicotinic receptors on smooth muscle (none, in fact, on most smooth muscle), so it just doesn't work. Paralyzing bronchospasm patients is also a risky proposition b/c positive pressure ventilation is very difficult in these folks and often just increases your existing air-trapping problem. The benefit of mag is that it DOES work on smooth muscle, because the relaxant effect of mag is basic to muscle physiology (it competes with calcium, and if Ca can't get into the muscle cell, it can't contract) and does not involve specific receptors.

[Thinking]

JLP, on 12 February 2012 - 03:33 PM, said:

. The benefit of mag is that it DOES work on smooth muscle, because the relaxant effect of mag is basic to muscle physiology (it competes with calcium, and if Ca can't get into the muscle cell, it can't contract) and does not involve specific receptors.

Mag has become my "go to" agent in status asthmaticus well ahead of IV Ventolin over the last 5 years. I've found it to work wonderfully.

[flynrn]

Although I retired from the air medical field I did transport a lot of rural, small EMS patients. One of my thought is "did the EMS accidently intubate her brain during their failed attempts at nasal intubation?" Just adding another thought to all the great responses.