Transcript for:
Myasthenic Crisis vs. Cholinergic Crisis

this is cereth registered nurse ari and.com and in this video i'm going to be going over my phoenix crisis versus call an urgent crisis in this video is part of an ink lex review series over the neuro system and as always don't forget to take the free quiz at the end of this youtube video so let's get started before we go over these two conditions and look at their similarities and their differences let's first go over the pathophysiology and see what's going on because these two complications can arise out of the neuro disease myasthenia gravis and if you're not familiar with that condition I have a whole lecture where I cover its pathos signs and symptoms are seen interventions and medications and you can access it up here in this card so here we have a neuron a nerve and we have a muscle fiber and these two meet together at what is called the neuromuscular Junction and that's what we're really interested in is this Junction and whenever this nerve which is a cholinergic fiber is stimulated by the central nervous system it releases a neurotransmitter called acetylcholine and the cetyl choline goes down here to these receptors which are in the marine color and these receptors are called nicotinic acetylcholine receptors and it causes this muscle fiber to contract now in Mycenae of gravis what's going on is that antibodies have been created by the immune system that attacked these receptors so you don't have all this acetylcholine go into those receptors like you should hence you're going to get muscle weakness so that's a big problem now that another thing I want to point out to you is hanging out in this neuromuscular Junction is called acetylcholine esterase and esterase remember it's like an enzyme it's an enzyme that breaks down acetyl choline and what it does is it breaks down acetylcholine which helps with like the recycling process of acetylcholine so this stimulation of this muscle fiber can keep going on and on however in myasthenia gravis we need to inhibit this slow that down because we don't want this acetylcholine being broken down because we need it for those receptors that are left over that aren't being attacked by this antibody created by the system so we can improve our muscle strength so patients will - ena gravis will be prescribed anti cola-cola estrus medications to prevent this process so keep that in mind okay now let's look at myasthenic crisis okay what's going on what's happening well this happens due to low to absolute no stimulation at the neuromuscular Junction by acetylcholine so no acetylcholine is getting to these receptors at all so what's going to happen we're gonna get severe muscle weakness which is gonna lead to respiratory failure because remember breathing requires you to use those voluntary muscles because myasthenia gravis affects voluntary muscles in the face the throat the respiratory system so they can get respiratory failure now on the flip side with cholinergic crisis what's happening is that there is excessive stimulation at the neuromuscular Junction by acetylcholine so acetylcholine is just going down on those nicotine ik acetylcholine receptors and just causing that muscle fiber to be stimulated constantly and it literally says I've had enough eventually after all this simulation and what happens with this is because you have that constant stimulation all that acetylcholine you have an overdrive in the cholinergic response which is going to be similar if you've seen the parasympathetic system in overdrive which is one of Tata ro signs and symptoms thing on here also in the end the patient's going to have severe muscle weakness and respiratory failure so here you can see that those two share those signs and symptoms because over here those muscle fibers have been stimulated so much that in the end they just give up and you have the weakness and respiratory failure over here they're just not being simulated at all by those cetyl choline so they're naturally going to be and have respiratory failure as well so what are the causes remember the causes because they're different cause and myasthenic crisis is that there's insufficient amount of the anti cholinesterase medication so typically patients will - inna gravis will be prescribed anti cholinesterase medications which again like we already talked about it's going to make more of that acetylcholine available at those receptor sites because that acetylcholine esterase is not going to be breaking down all that acetylcholine however it's there - in your gravis isn't being treated appropriately they need more medication so this crisis comes out also it can be caused by a patient who has myasthenia gravis they experience an acute exacerbation where they're experiencing just a high amount of stress can be like surgery physical stress mental stress or a respiratory infection now over here we call an urgent crisis a cause is receiving too much of their anti cholinesterase medication so patient has my senior gravis maybe they're receiving too high of a dose of this medication and it is stopping the breakdown of acetylcholine so there's more at that neuromuscular junction which is great in myasthenia gravis but if you've got way too much there you're going to have too much of it which is going to cause the cholinergic crisis and those muscle fibers are just going to be over stimulated so let's look at those signs and symptoms in detail cuz even though they share in the end muscle weakness and respiratory failure they have some other little signs and symptoms that are a little bit different so over here - Enoch crisis some signs and symptoms they will have dilated pupils increase heart rate increase blood pressure no coughs or gag because remember those muscles that are responsible for allowing us the coughing gag and swallow they are not working they're severely weak because they're not getting any signals to contract they're going to be at risk for ask raishin they can't swallow can't speak and incontinence of the bow and bladder because again those muscles to help you void to have a bowel movement are not going to be working the way they should we call an urgent crisis signs and symptoms again like I said it's gonna be similar to if that parasympathetic system is an overdrive overdrive and what was a parasympathetic nervous system it was it's one of those rests and digest systems on the flip side the sympathetic nervous system was the fight-or-flight so this is some parasympathetic gets us ready to digest food to rest reproduce things like that so you're gonna have GI issues over here where you have increased gastric motility so vomiting diarrhea abdominal cramping the pupils are going to constrict increased salivation and tears which will cause blurred vision also they'll have an increase in respiratory secretions so their airway is also at risk because of this and muscle fasciculations and this is where they have twitching okay the muscle fiber has just been constantly stimulated so that can cause these twitching but in the end it can lead to paralysis where they're flaccid and they will have decreased heart rate and a decreased blood pressure so other than the signs and symptoms how are these two conditions diagnosed because remember they're going to share the severe muscle weakness and the respiratory failure well the neurologist can order a test called at insulin tests and during this test a medication is administered called a Dro phony Amanda draconian is an anti colonist race medication so remember the function of acetylcholine esterase if we're blocking that what's going to happen in each condition you're gonna get different responses whenever this medication is administered and it can tell you are they having a myasthenic crisis or cholinergic crisis so if we give a drew phoneme to someone who's in a seneschal cholinergic crisis well what are we doing we're adding more acetylcholine at this neuromuscular Junction which is not what this patient needs because remember the problem was is that these nicotinic acetylcholine receptors are being overstimulated so we're just going to throw more acetylcholine there we are going to have worsening of the signs and symptoms in that patient they're not gonna get better they're gonna get worse off so the test result will be negative so treatment what would the treatment for this we want to reverse the signs and symptoms of this overdrive in this cholinergic response in an antidote for a geophone iam is atropine so gonna give atropine reverse the signs and symptoms and hold any further doses of that anti cholinesterase medication because patient really doesn't need any of that right now now if we give a drug phoneme to a patient who's in a potential myasthenic crisis what are we doing again we're adding more acetylcholine at that neuromuscular junction which is great because they need some more of that so they're actually going to have improvement of their signs and symptoms and they're going to look and feel better and the test result would be a positive test result and treatment for the MD order would be ordering some more anti cholinesterase medication okay so that wraps up this lecture on my scenic crisis versus call an urgent crisis thank you so much for watching don't forget to take the free quiz and to subscribe to our channel for more videos