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Ak68w
01-17-2009, 18:45
Good afternoon Docs. I have a question regarding treatment of Anaphylaxis patients. I was talking about the subject with a nurse I work with (I work in an OR) and he said that in anaphylaxis with the standard issue hypotension, epi is the key, just like every EMT book ever written says. But then he said something interesting; that you must check BP in anaphylaxis patients because in the unlikely occurence that the patient is hypertensive, atropine is the treatment of choice.
My questions are:
1) Has anyone ever actually encountered this? Before the OR Nurse said it, I'd never even heard about it before.
2) If so, is the difference in BP due to the allergen itself, or simply the patient? Where and why does it happen?
3) As the medic, what happens if I give epinepherine to a hypertensive anaphylactic patient? What if I give atropine to the hypotensive guy?
4) Are there any other signs and symptoms of anaphylaxis that would dictate a radically different course of action (like giving epi versus atropine)?
The nurse was unable to answer many of these questions, simply because he's used to the controlled environment of the OR, whereas I'm curious about ramifications in unpredictable field environments. Anyways, I figured if anyone would know, it'd be you QPs! Thanks for any and all info.

Brush Okie
01-17-2009, 19:04
I have been out of the loop for several years but have treated this condition several times. I have never heard of Atropine given for allergic reaction. Others here may have better updated information.

ANY medication you give has the potental for bad results be it bad side effects or allergic reaction, so the benefits have to outweigh the risk. I have never had a hypertensive person with allergic reaction, but I know what will happen if you don't give the eppi. Anaphylaxis happpens very fast so you really have to move even if it is only a mild to moderate allergic reaction it can get deadly fast.

With anaphylaxis is the airways close up, the blood vessels dialate and you even get a lot of third spacing of fluid sometimes. Eppi is an alpha and beta stimulant so it opens the air passeges and constricts the blood vessels among other things, but that is the effects you are looking for. The secondary medication you want to give is IV benedryl. It is a histamene blocker.

Contraindication is allergy. If someone had heart disease or is over 40 you may want to reconsider giving them according to the book, but unless there is a known heart risk I would probably give the eppi since the anaphalaxis is so deadly. If there was some reason not to give eppi then my first medication would be Benedryl aka diphenhydromine. (sp?) Those two can be followed up with something like Decadron if there is a lot of swelling, but that is not usually given in the field.

Like I said I have been out of the game for a while others here may have better or updated info. Also this is the simplified version, it is a bit more complex than stated here.

swatsurgeon
01-18-2009, 10:07
before we discuss this further...use Google or WebMD and look up the indications for atropine. It is not a first line agent for anaphylaxis, it can be an adjunct. Read more then discuss....this is the way of education.

ss

swatsurgeon
01-18-2009, 10:16
well, I couldn't take it any longer.....
the nurse you speak of with great knowledge will potentially harm a patient who is having a true anaphylactic episode if atropine is given as a first line agent.
First off, the rxn causes hypotension not hypertension. If there is an element of hypertension than either (a) wrong diagnosis, (b) patient acute anxiety/agitation is occuring and temporarily increased BP over a brief period of time. Anaphylaxis causes the release of histamine and lowers BP, not raises it (under normal circumstances). All atropine will do is speed up the heart by blocking vagus nerve stimulation which is the overriding output/regulation to the heart.....
so query me this: how does a vagolytic drug treat anaphylaxis??
This is where education comes in.............

Ak 68w, i await your reply

ss

adal
01-18-2009, 11:09
ss,
You bit your tongue longer than I thought you would, 9 min. It became a topic of discussion here at my flight agency. Sad was the end result.

Ak68w
01-18-2009, 15:42
First off, the rxn causes hypotension not hypertension. If there is an element of hypertension than either (a) wrong diagnosis, (b) patient acute anxiety/agitation is occuring and temporarily increased BP over a brief period of time. Anaphylaxis causes the release of histamine and lowers BP, not raises it (under normal circumstances).
That's why it seemed so odd to me when the nurse said it; I always thouhgt hypotension was a sign of Anaphylaxis. As far as the Atropine goes, before he had mentioned it, I knew the name, I knew it was a beta blocker, and I knew it helped patients with uncontrollable tremors (i.e., Parkinsons) and certain over-productive glands. Beyond that, I knew nothing of the drug as far as emergency indications/contraindications, what exactly it does, etc. etc.

Now you said that histamine lowers not raises BP, under normal circumstances. Do you mean normal as in normal patients, or normal conditions? If the latter, what preparations and precautions should I as the medic take when my unit and I take to the field? And what should I do then if I find a hypertensive anaphylactic patient? Thank you for this info SS!

swatsurgeon
01-18-2009, 18:04
That's why it seemed so odd to me when the nurse said it; I always thouhgt hypotension was a sign of Anaphylaxis. As far as the Atropine goes, before he had mentioned it, I knew the name, I knew it was a beta blocker, and I knew it helped patients with uncontrollable tremors (i.e., Parkinsons) and certain over-productive glands. Beyond that, I knew nothing of the drug as far as emergency indications/contraindications, what exactly it does, etc. etc.

Now you said that histamine lowers not raises BP, under normal circumstances. Do you mean normal as in normal patients, or normal conditions? If the latter, what preparations and precautions should I as the medic take when my unit and I take to the field? And what should I do then if I find a hypertensive anaphylactic patient? Thank you for this info SS!

hold on......IT IS NOT A BETA BLOCKER!!!!! please do some research on this!!
You should rarely if ever find a patient with hypertension and anaphylaxis. The 'under normal circumstances' means the majority of patients...not the ones on crack/meth/etc or medications that raise the BP. Again, read about the subject of anaphylaxis and atropine, it will do more for you than reading my posts, I'm just an ordinary trauma surgeon

ss

Red Flag 1
01-18-2009, 18:18
hold on......NOT A BETA BLOCKER!!!!! please do some research on this!!
You should rarely if ever find a patient with hypertension and anaphylaxis. The 'under normal circumstances' means the majority of patients...not the ones on crack/meth/etc or medications that raise the BP. Again, read about the subject of anaphylaxis and atropine, it will do more for you than reading my posts, I'm just an ordinary trauma surgeon

ss


Oh good Lord!!

Looks like this has left the world of 18D's, IMHO.

OR nurses are of great value in the operating room. They see a lot, and miss very little. The responsibility of OR nurses have little to do with treating patients, and should be considered in that light.

My $.02.


RF 1

Doczilla
01-18-2009, 22:39
Things are going terribly wrong here...

Atropine is not a beta blocker, as SS pointed out. Atropine can be a bronchodilator since it is a vagolytic drug, and a similar drug, Atrovent (Ipratropium Bromide) is inhaled to help with bronchodilation. In a pinch, you could nebulize atropine for bronchodilation, but I don't recommend doing this if you have Atrovent available. Atropine's role in anaphylaxis is quite limited, so I'd put it out of your mind. I can really only see giving atropine if the secretions are so severe as to compromise the airway or if the patient has profound bradycardia.

If the patient was hypertensive (rare, and should make you question the diagnosis of anaphylaxis), I would gear therapy toward relieving the bronchoconstriction with beta agonists such as inhaled albuterol in conjunction with inhaled ipratropium. Systemic steroids and antihistamines would also be indicated. If air movement was compromised enough, I'd give the epi anyway in spite of the elevated blood pressure. Anxiety from hypoxia can potentially elevate BP and heart rate, so you need to get to the underlying problem of airway compromise.

Patients with a HISTORY of hypertension may be TAKING beta blockers (drugs that end in -olol, such as metoprolol, atenolol, propranolol, and a couple of exceptions to this rule, carvedilol and labetalol), which may make them resistant to the epinephrine you are giving to reverse the bronchoconstriction and vasodilation which normally accompanies anaphylaxis. For these patients, glucagon may be helpful, as this will activate many of the same pathways as epi but without needing to interact with the beta receptors.

'zilla

Ak68w
01-18-2009, 23:49
OK. Thanks a ton to all of you for squaring me away on this! So, to recap and make sure I've got my stuff straight now:

The primary first line treatment for Anaphylactic shock is still eppi.
If I should find a persistently hypertensive Anaphylactic patient (not just the result of the patient freaking out), I should most certainly question the diagnosis of Anaphylaxis, and focus on securing the airway and relieving the bronchoconstriction.
If the patient has a history of hypertension, he/she might be taking beta-blockers (anything ending in -olol), so the eppi might not be as effective. For these guys, give glucgon a shot.
Beyond that, the basics of treatment for Anaphylaxis remain the same, O2, IV fluids to help raise the BP, albuterol if you have it, same for IV diphenhydramine, package the guy up, and move fast. Obviously monitoring all vitals along the way. Don't worry about Atropine, my time is better spent worrying about blocking histamines, raising BP, and bronchodilation.
...
...and Atropine is NOT a beta-blocker.

I think I got everything finally squared away. One last question: Amongst medics at my unit there has always been the debate: if I catch the Anaphylaxis early enough and make the call to intubate (obviously assuming the patient is unconscious), can the swelling of the airway get so severe as to pinch my artificial airway shut? If so, what the hell do I do then?!

Brush Okie
01-19-2009, 00:37
OK. Thanks a ton to all of you for squaring me away on this! So, to recap and make sure I've got my stuff straight now:

The primary first line treatment for Anaphylactic shock is still eppi.
If I should find a persistently hypertensive Anaphylactic patient (not just the result of the patient freaking out), I should most certainly question the diagnosis of Anaphylaxis, and focus on securing the airway and relieving the bronchoconstriction.
If the patient has a history of hypertension, he/she might be taking beta-blockers (anything ending in -olol), so the eppi might not be as effective. For these guys, give glucgon a shot.
Beyond that, the basics of treatment for Anaphylaxis remain the same, O2, IV fluids to help raise the BP, albuterol if you have it, same for IV diphenhydramine, package the guy up, and move fast. Obviously monitoring all vitals along the way. Don't worry about Atropine, my time is better spent worrying about blocking histamines, raising BP, and bronchodilation.
...
...and Atropine is NOT a beta-blocker.

I think I got everything finally squared away. One last question: Amongst medics at my unit there has always been the debate: if I catch the Anaphylaxis early enough and make the call to intubate (obviously assuming the patient is unconscious), can the swelling of the airway get so severe as to pinch my artificial airway shut? If so, what the hell do I do then?!

O2
IV
moniter

mild to moderate .3 to .5 mg 1:1000 eppi sq

secondary is 25-50 mg Benedryl IV

For severe anaphylaxis .5 1:10,000 SLOW IV instead of SQ. I'v done this in the back of a moving ambulance and the pucker factor is high. Push it to fast and you can kill the guy, too slow and they die. This is a last resort thing and they can die anyway when they are this bad. Mine didn't but it can happen. NOTE the diffrent strength in eppi. If you push the higher concentrate eppi IV you WILL kill the person.

If the airway is swelling shut, you can try to intubate first but eppi might be your best tx. It depends on the circumstances.

If they are hypertensive it is either they are having a diffrent dx, or they have uncontrolled high blood pressure. Either way with ABC's airway is first. Don't forget the basic's. Without air you will die fast.

What ever you do get more training than this thread before carrying eppi since at this point you don't seem to have the training to mess with the drugs. i'm not trying to be a jerk, but a little knowledge can be dangerious.

Red Flag 1
01-19-2009, 08:43
OK. Thanks a ton to all of you for squaring me away on this! So, to recap and make sure I've got my stuff straight now:

The primary first line treatment for Anaphylactic shock is still eppi.
If I should find a persistently hypertensive Anaphylactic patient (not just the result of the patient freaking out), I should most certainly question the diagnosis of Anaphylaxis, and focus on securing the airway and relieving the bronchoconstriction.
If the patient has a history of hypertension, he/she might be taking beta-blockers (anything ending in -olol), so the eppi might not be as effective. For these guys, give glucgon a shot.
Beyond that, the basics of treatment for Anaphylaxis remain the same, O2, IV fluids to help raise the BP, albuterol if you have it, same for IV diphenhydramine, package the guy up, and move fast. Obviously monitoring all vitals along the way. Don't worry about Atropine, my time is better spent worrying about blocking histamines, raising BP, and bronchodilation.
...
...and Atropine is NOT a beta-blocker.

I think I got everything finally squared away. One last question: Amongst medics at my unit there has always been the debate: if I catch the Anaphylaxis early enough and make the call to intubate (obviously assuming the patient is unconscious), can the swelling of the airway get so severe as to pinch my artificial airway shut? If so, what the hell do I do then?!


I don't believe there will be any problem with endotracheal intubation, if it is indicated. The airway restriction is generally in the smaller airways. Intubation will not solve the broncho constriction downstream, that is were the epi comes in.

RF 1

RF 1

shr7
01-19-2009, 15:48
A perfect example of the problem of memorizing the "what" instead of the "why" with potentially devastating consequences. If you learn the physiology and why certain drugs are used, and why these drugs have the effects that they do, you have much less of a chance becoming bogged down with the details.

Of course, there are always exceptions. That's why "I'm not sure of the answer right now, but I can go look it up for you" was invented.

SR

Doczilla
01-20-2009, 23:01
O2
IV
moniter

mild to moderate .3 to .5 mg 1:1000 eppi sq

secondary is 25-50 mg Benedryl IV

Let me clarify something here. For mild to moderate allergic reactions, benadryl and steroids (solumedrol, decadron, or prednisone if they can swallow), +albuterol nebulizers for accompanying wheezing. SQ epi is not for mild to moderate anything. With severe anaphylaxis, with hypotension or airway compromise, then epi as above.


For severe anaphylaxis .5 1:10,000 SLOW IV instead of SQ. I'v done this in the back of a moving ambulance and the pucker factor is high. Push it to fast and you can kill the guy, too slow and they die. This is a last resort thing and they can die anyway when they are this bad. Mine didn't but it can happen.

Everyone I know who has pushed IV epi for anaphylaxis has regretted it. I know this is mentioned in the books, but it's a really bad idea unless they are pulseless. Much safer to just go SQ or IM.


NOTE the diffrent strength in eppi. If you push the higher concentrate eppi IV you WILL kill the person.

This is incorrect. Epi in the 1:1000 concentration has been used IV for some number of years. The difference between this and the 1:10,000 is 9cc of water.

'zilla

RichL025
01-20-2009, 23:16
Second what Doczilla said.

Especially about leaving off the epi of you don't need it.

My very first real medical situation was during Robin Sage (hell, I was still technically an 11B) - my team leader had anaphylaxis from a bee sting. Classic presentation. Hit 'em with the SQ epi & Benadryl, he responded well, and started arranging evac.

Evac was delayed, and after about 45 minutes his breathing started worsening again. This time I tried IM benadryl only... it gave him subjective airway relief (and improved his wheezing) in less than 5 minutes.

If you think you can wait, or if the reaction doesn't seem airway-threatening, benadryl alone is just fine.

Oh yeah- don't do like I did and forget to give some steroids also, otherwise they'll be coming to you the next day asking about this itchy rash....

Brush Okie
01-21-2009, 00:27
Let me clarify something here. For mild to moderate allergic reactions, benadryl and steroids (solumedrol, decadron, or prednisone if they can swallow), +albuterol nebulizers for accompanying wheezing. SQ epi is not for mild to moderate anything. With severe anaphylaxis, with hypotension or airway compromise, then epi as above.



Everyone I know who has pushed IV epi for anaphylaxis has regretted it. I know this is mentioned in the books, but it's a really bad idea unless they are pulseless. Much safer to just go SQ or IM.



This is incorrect. Epi in the 1:1000 concentration has been used IV for some number of years. The difference between this and the 1:10,000 is 9cc of water.

'zilla

Thanks for the update. The ONE time I did push IV eppi for anaphalaxsis I was scared to death, but that is what base hosp said to do. It was close to 20 years ago, so details are lost, but I remember he had no BP to speak of. I pushed it very slooooowwwww with one eye on the moniter at all times.

I was told in school to not push 1:000 since it could go in too fast and kill them. That is also how our protocols were written. I was always told to draw up 9cc NS with the 1cc eppi for IV or just use a pre load 1:10000. Not disagreeing, just trying to remember our protocols.

The mild to moderate was considered for wheezing etc where there was sx of airway problems only. Hives did not count for getting eppi. Not until later years was albuteral or any SVN in our protocols so it was eppi and benedryl or nothing for a while. Anyone over 40 or with HX of heart problems no eppi unless no other choice.

Like I said in my post, I have been out of the game for several years, things change and I forget things over time. I do appreciate the correction. Nothing like the wrong or outdated information to kill someone.