what is the procedure for determining general anesthetic allergies.

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.

linktim

Full Member
10+ Year Member
Joined
Oct 4, 2008
Messages
14
Reaction score
0
Hi guys, I am a med student. I want to ask a one question. When someone is allergic to general anesthesia, what do you do to check? I mean you cannot put the guy to sleep and go oh well..... he ain't breathing .

thanks in advance.

Members don't see this ad.
 
yeah, we don;t say "oh well", we just note that the patient is apnic.
 
Give patient triggering agents.
Bad things happen.
Diagnose MH.
Resuscitate patient. (hopefully)
Don't give triggering agents ever again.
The end.
(maybe test family members)

Or were you referring to detecting drug allergies in an anesthetized patient?
As an aside, you don't frame questions very well for a medical student.🙄
 
Members don't see this ad :)
Actually, our usual goal when inducing general anesthesia is to stop spontaneous respirations.

If that's your measure of allergy/anaphylaxis, I would like to report a near-100% rate of allergies in my patients.
 
Anaesth Intensive Care. 2008 Mar;36(2):201-7.
Review of procedures for investigation of anaesthesia-associated anaphylaxis in Newcastle, Australia.

McNeill O, Kerridge RK, Boyle MJ.

Department of Immunology, John Hunter Hospital, Newcastle, New South Wales, Australia.
Abstract

The procedures, results and outcomes of investigation of 50 patients with clinical episodes of anaesthesia-associated anaphylaxis were retrospectively reviewed. Assessment was performed by measurement of serum tryptase and specific IgE and a combination of skin prick and intradermal skin testing. Testing was performed both for agents received during the anaesthetic and for agents the patient may encounter in future procedures. Twenty of 50 patients underwent a subsequent procedure after assessment. Sensitisation to neuromuscular blocking agents was identified in 18 patients (36%). Sensitisation to propofol (14 patients; 28%) and latex (four patients; 8%) was also frequently identified. No precise cause was identified in 11 cases (22%). Reactivity to more than one agent was identified in 14 patients (28%). Serum tryptase was measured within six hours of the episode in only 28 of the 50 cases. All the patients with elevated serum tryptase had clinically severe reactions. One patient initially found to be sensitised to propofol had another reaction during a second procedure, prompting further assessment where chlorhexidine reactivity was identified. Subsequent surgery in that patient and in 19 other patients where agents implicated in the testing were avoided, proceeded without incident. The results reaffirm that neuromuscular blocking agents are the most common cause of anaphylaxis during anaesthesia. The importance of serum tryptase measurement at the time of the acute episode needs to be emphasised. Investigation should include screening for chlorhexidine and latex in all patients, as exposure to both these agents is common and may be overlooked.
 
If that's your measure of allergy/anaphylaxis, I would like to report a near-100% rate of allergies in my
patients.

LOL. 😀

As an aside, you don't frame questions very well for a medical student.🙄

Sometimes I feel like you guys let ME off the hook with my questions around here. I consider myself lucky. 😉

D712
 
Hi there. When I first started reading about the subject, I thought that the skin prick test was only for local anesthetic. I was under the(misguided) impression that for general anesthesia, they make you breathe in a very low concentration to see if you break out in hives or something.

One last thing, in all general anesthesia, are there some drugs or cases where the machine does not breathe for the patient, or does the machine do all the breathing in every case?
 
Actually, our usual goal when inducing general anesthesia is to stop spontaneous respirations.

If that's your measure of allergy/anaphylaxis, I would like to report a near-100% rate of allergies in my patients.

Allergy to morphine - "it makes me sleepy"
Allergy to codeine - "it makes me feel funny"
Allergy to sulfa - "I dunno my niece and BFF are so I figure I must be too"
Allergy to Novocaine - "it makes me drool"
Allergy to general anesthesia - "it makes me quit breathing"

Crazy is as crazy does.
 
One last thing, in all general anesthesia, are there some drugs or cases where the machine does not breathe for the patient, or does the machine do all the breathing in every case?

It's not as much about drug selection as it is dose given. You can take any drug in anesthesia, give it at a lower dose, and maintain spontaneous respiration and consciousness. Give a little more, you can deliver deep sedation while maintaining breathing. Give a little more, they're done breathing.

Same with the machine. What most people think of as "anesthesia" is actually a broad spectrum from feeling a little silly while someone jams a snake up your transverse colon, to feeling nothing, asleep and dependent on a ventilator, while a surgeon picks your heart up, flips it over and sews a coronary graft. Got a brain tumor? You can be completely asleep, or wide awake while the neurosurgeon plucks it out. We do it all.
 
Anaesth Intensive Care. 2008 Mar;36(2):201-7.
Review of procedures for investigation of anaesthesia-associated anaphylaxis in Newcastle, Australia.

McNeill O, Kerridge RK, Boyle MJ.

Department of Immunology, John Hunter Hospital, Newcastle, New South Wales, Australia.
Abstract

The procedures, results and outcomes of investigation of 50 patients with clinical episodes of anaesthesia-associated anaphylaxis were retrospectively reviewed. Assessment was performed by measurement of serum tryptase and specific IgE and a combination of skin prick and intradermal skin testing. Testing was performed both for agents received during the anaesthetic and for agents the patient may encounter in future procedures. Twenty of 50 patients underwent a subsequent procedure after assessment. Sensitisation to neuromuscular blocking agents was identified in 18 patients (36%). Sensitisation to propofol (14 patients; 28%) and latex (four patients; 8%) was also frequently identified. No precise cause was identified in 11 cases (22%). Reactivity to more than one agent was identified in 14 patients (28%). Serum tryptase was measured within six hours of the episode in only 28 of the 50 cases. All the patients with elevated serum tryptase had clinically severe reactions. One patient initially found to be sensitised to propofol had another reaction during a second procedure, prompting further assessment where chlorhexidine reactivity was identified. Subsequent surgery in that patient and in 19 other patients where agents implicated in the testing were avoided, proceeded without incident. The results reaffirm that neuromuscular blocking agents are the most common cause of anaphylaxis during anaesthesia. The importance of serum tryptase measurement at the time of the acute episode needs to be emphasised. Investigation should include screening for chlorhexidine and latex in all patients, as exposure to both these agents is common and may be overlooked.

Yeah, but what does sensitization actually tell us about the risk for anaphylaxis? I'm on peds right now, and the allergy/immunology docs just finished giving us a lecture on how ridiculous it is that pediatricians will shotgun IgE panels looking for food "allergies" that come back mostly "positive" but have no clinical significance. Obviously, the higher the level, the more worrisome it is, but I wonder what percent of the general population will have a "positive" IgE to NMBAs or propofol without any adverse effect. (Sorry if the answer is in the paper, I'll look at it more fully tomorrow as I'm heading to bed).
 
Hi guys, I am a med student. I want to ask a one question. When someone is allergic to general anesthesia, what do you do to check? I mean you cannot put the guy to sleep and go oh well..... he ain't breathing .

thanks in advance.

I've never heard of anyone being allergic to volatile anesthestics if that's what you are asking about. When there IS an allergic reaction under anesthesia, the volatile isn't even considered in the differential and isn't discontinued.
 
I've never heard of anyone being allergic to volatile anesthestics if that's what you are asking about. When there IS an allergic reaction under anesthesia, the volatile isn't even considered in the differential and isn't discontinued.

He's a med student, I took his use of "anesthesia allergy" to be the layman's term for malignant hyperthermia.
 
Top