flumazenil

[New CCU RN]

quick question.. i had a pt who was intubated for airway protection secondary to ugb... egd performed, ulcer cortorized and epi given and bleed was stable...we wanted to do a rapid extubation...no underlying lung disease but the patient was alert not enough....no following commands and no sustained eye contact, but had recieved alot of versed during the scope because of her agitation level..also elderly... i suggested a reversal agent bc the patient was a dni but agreed just for the scope and bc the only reason she was still intubated s/p the procedure was waiting for the versed to wear off... docs refused secondary to increased risk for seizure activity if given flumazenil....ive never heard of this... any thoughts on this??? just wondering...

she needed to get off the vent... ulcer was stable, hgb stable, no active bleeding and her gas was great... 7.39 41 344 yes 344 24.5 -.7 100% drawn on spontaneous breathing, 35% peep 5 psv 8

[New CCU RN]

should clarify my role... i am an rn in an icu setting.. if that makes any difference...

[arkgolfer]

Seems to be some controversy in the anesthesia literature about this. Stoelting and Miller sugggest usage doesn't precipitate, however Katzung, M&M suggest there is an increased risk, especially with longterm use of BZDs. Per package insert: should be aware of a risk of seizure in association with flumazenil treatment, particularly in long-term BZD users and TCA overdose.

Maybe this patient had some history with BZDs or TCAs.

Hope this helps. Just happen to be studying about this now.

[AnesthesiaBound]

Good response Arkgolfer. In my experience, there are a multitude of older people on TCAs and/or BNDs - either for depression, itching, etc, etc. Something to think about.

bj

[New CCU RN]

The patient had no med hx... wouldn't even take ASA for a headache... unless there was something I didn't know.. thanks for the info though. That's neat you are studying it right now :)

[New CCU RN]

anyhow, she now will be intubated overnight as opposed to rapid extubation which was the original plan... i feel awful for her considering her wishes and she only reversed them thinking the procedure would be quick and the ett out soon after which was what we were all anticipating... but then again sz activity is not fun either i suppose it is better to take the safer route

[Tenesma]

i wouldn't give flumazenil either ... for two reasons...

1) old ladies for some reason always have an endless stash of valium that they take for sleeping and they never tell you about it... so there flumazenil is definitely risky and thus the risk for worsening agitation and possibly seizures

2) if this old lady has been pumped with versed then the flumazenil will wear off way before (lasts about 45 minutes) the versed wears off - then you are in a sticky situation because she will need to be possibly intubated again because of poor medical judgement

so in summary since this lady is DNI you want to make sure that she is perfect when you extubate

[New CCU RN]

aha... i didn't realize the #2 part...my assumption was that it totally reversed it not just for x amount of time... that makes more sense now...

another question...... i hope this doesn;t sound dumb, but increasing ivf help her clear faster... ?? just wondering...

[Tenesma]

increasing IVF per say wouldn't increase clearance of versed...

it is primarily metabolized in the liver (so is flumazenil by the way), and therefore if you want to increase clearance you will have to increase hepatic flow (tough to do), put the patient on an artificial liver (expensive to do - and dangerous), or add another drug that stimulates cytochrome P450 activity (some growth hormones, ETOH, phenobarb) - and that actually may work against you as ETOH and phenobarb won't help with the mental status... i know this sounds tongue in cheek (but it is late and i am between cases - finished a ruptured LV and on to something else exciting...)

[Brenna's Dad]

Interesting response concept to increase her P450 enzymatic activity in an effort to increase liver metabolism. Probably impractical though, since increasing enzymatic activity would probably take at least a week.

If i remember correctly, versed is also a high extraction ration drug, so increasing hepatic blood flow would not increase metabolism. Please correct me if I'm wrong. (I suppose I could reach over to my bookshelf and look it up, but I'm tired)

Interesting response concerning old ladies valium stash.

Does anyone know why flumazenil would be contraindicated in individuals on TCA's. I know TCAs decrease SERT and NERT, but can't make the connection as to why a BZD receptor antagonist would increase seizure potential in this group of patients.

[Tenesma]

i wrote my thesis on cytochrome p450 - it just takes a few hours...

it is a post-transcriptional mrna mediated process

[Brenna's Dad]

You would know then.... it was my understanding that P450 stimualtion would take longer than that.

Very interesting.

Anyone have an answer to the flumazenil and TCA question?