Intraop Seizure

[eggscal99]

Long time lurker here. Enjoyed reading clinical discussions. I'm quite fresh out of training and would appreciate any feedback or wisdom about a recent case:

50 yo F for elective lumbar laminectomy. PMH of lupus anticoagulant with previous right central retinal vein thrombosis on plavix + coumadin, off both for 5 days for surgery. She's on Plaquenil, CellCept, Prednisone for SLE. No h/o HTN, DM, stroke, heart/lung/renal/hepatic issues. 100kg BMI 35. NKDA. No previous GA anesthetic issues. METS>4. Standard ASA monitors, induced with fentanyl 50mcg, propofol 200mg, lidocaine 40mg, sux 100mg. Easy DLx1 intubation without issue. Post-induction A. line. VSS throughout induction and pre-incision with BP roughly 140s/80s, HR 70s, SpO2 100%, ETCO2 roughly 35, NSR. Anesthesia maintained with ETsevo 1.8 at this point. Rocuronium 20mg given (wanted to preserve motor for MEP but wanted to decrease moving/bucking when flipping), then pt flipped prone, all VSS, ETT checked good position with same ETCO2. At this point pt was being preped, surgeon scrubbing, then suddenly... what appeared to be a generalized tonic-clonic seizure. Immediately administered versed, large propofol bolus, ABG drawn (ph 7.32/ CO2 42/O2 426/bicarb 21.6), labs (K4.0, glu 97, neg TnI), sent to ICU, Keppra given. CXR neg, EKG NSR, stat CT head no bleed/midline shift/lesion, but focal decreased left MCA superior branch diameter poss. thrombus vs. stenosis. Stat MRI negative for ischemia. EEG in ICU no seizure activity. VSS in ICU.

Of course, per neuro, the "new onset seizure" was likely "a reaction to the anesthetic" since surgery hadn't started yet. I did some preliminary reading saying that fentanyl, propofol, sevo can all induce seizure activity. But these are the most commonly used agents.

What should I have done differently? What induction agents would you choose or what would you do, if she came back a few weeks later for a repeat procedure? Thanks in advance for any feedback.

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[urge]

Long time lurker here. Enjoyed reading clinical discussions. I'm quite fresh out of training and would appreciate any feedback or wisdom about a recent case:

50 yo F for elective lumbar laminectomy. PMH of lupus anticoagulant with previous right central retinal vein thrombosis on plavix + coumadin, off both for 5 days for surgery. She's on Plaquenil, CellCept, Prednisone for SLE. No h/o HTN, DM, stroke, heart/lung/renal/hepatic issues. 100kg BMI 35. NKDA. No previous GA anesthetic issues. METS>4. Standard ASA monitors, induced with fentanyl 50mcg, propofol 200mg, lidocaine 40mg, sux 100mg. Easy DLx1 intubation without issue. Post-induction A. line. VSS throughout induction and pre-incision with BP roughly 140s/80s, HR 70s, SpO2 100%, ETCO2 roughly 35, NSR. Anesthesia maintained with ETsevo 1.8 at this point. Rocuronium 20mg given (wanted to preserve motor for MEP but wanted to decrease moving/bucking when flipping), then pt flipped prone, all VSS, ETT checked good position with same ETCO2. At this point pt was being preped, surgeon scrubbing, then suddenly... what appeared to be a generalized tonic-clonic seizure. Immediately administered versed, large propofol bolus, ABG drawn (ph 7.32/ CO2 42/O2 426/bicarb 21.6), labs (K4.0, glu 97, neg TnI), sent to ICU, Keppra given. CXR neg, EKG NSR, stat CT head no bleed/midline shift/lesion, but focal decreased left MCA superior branch diameter poss. thrombus vs. stenosis. Stat MRI negative for ischemia. EEG in ICU no seizure activity. VSS in ICU.

Of course, per neuro, the "new onset seizure" was likely "a reaction to the anesthetic" since surgery hadn't started yet. I did some preliminary reading saying that fentanyl, propofol, sevo can all induce seizure activity. But these are the most commonly used agents.

What should I have done differently? What induction agents would you choose or what would you do, if she came back a few weeks later for a repeat procedure? Thanks in advance for any feedback.

I wasn't there, but from what you wrote my guess is that the patient was light and was trying to move. I would expect anyone to be jumping around with very little fentanyl, low gas, and minimal paralysis. I can imagine it looks more impressive while prone.

More fentanyl and more gas for the next one.

 

[eggscal99]

I wasn't there, but from what you wrote my guess is that the patient was light and was trying to move. I would expect anyone to be jumping around with very little fentanyl, low gas, and minimal paralysis. I can imagine it looks more impressive while prone.

More fentanyl and more gas for the next one.

Definitely could being light, or shivering. The neurosurgeon saw it and was convinced it was seizure. I wasn't entirely convinced, because with versed and propofol boluses didn't do a whole lot to subside the activity. But afterwards when I took her to ICU and she kept doing this repetitive leg jerking I just wasn't sure what it was. With negative EEG, CT, MRI, labs I'm less convinced it was a seizure. But the neurologist already labeled it as new onset seizure and I'm not sure what to tell the patient/family? "Look, contrary to what the neurologist said, I don't think it was a seizure, we just overreacted"??

 

[caligas]

Sometimes patients shudder violently when prone, incubated, and light. (Never happens to MY patients, but I've heard)

 

[urge]

But the neurologist already labeled it as new onset seizure and I'm not sure what to tell the patient/family? "Look, contrary to what the neurologist said, I don't think it was a seizure, we just overreacted"??

I wouldn't say that. I would play along, but for the next ones make sure they are deep.

 

[deleted162650]

Next time don't confuse getting baseline MEPs as seizure activity. You're welcome.

 

[chocomorsel]

I do spine almost all day every day. I can pretty much guarantee you this was not a seizure. It was most likely,
A: A light patient, who reacts to being moved to prone position;
B: What Salty Said, Getting baseline MEPs, which don't send the whole patient twitching, but can trigger a jerky whole body reaction from the patient since he/she was most likely light.

I wasn't there, but every time I move my patients I disconnect the ETT, and they end up on the lighter side and since most aren't paralyzed, they move occasionally. It can be pretty dramatic sometimes. I just turn the machine to manual, turn gas up, bag them and give more narcs/white stuff and make sure they aren't falling off the bed.

No biggie.

 

[chfo]

I've seen some weird s***, but a seizure under general ain't one of them.

I would evaluate every other possibility before thinking it was a seizure.

 

[deleted162650]

Neuro monitoring shoulda been able to show you EEG on the spot. Pretty F'in hard to seize through GA.

 

[drmwvr]

Good for the neurologist... now no matter what anyone says she'll insist that whatever elements of GA she got that day causes seizures. Probably'll carry a copy of the record just to make sure someone doesn't do it again.

 

[Scotty_G]

No sane anesthesiologist is going to avoid giving volatile anesthesia because of this. Do not worry It most likely wasn't a seizure, but sevo has been shown to decrease seizure threshold.

 

[chocomorsel]

Neuro monitoring shoulda been able to show you EEG on the spot. Pretty F'in hard to seize through GA.

Yup. Those squiggly lines mean something.

 

[Robotic Wis-Hipple]

Once again, proof literally nobody, even other physicians, including neurology/surgery have any clue what we do or how we do it.

Not sure how long between induction and flipping, likely 15min if anything like our neuro monitoring prone cases so propofol likely mostly gone but 1.8 sevo should be plenty. 50mcg fent and 100mg sux seems light to me though. I'd wager not enough to blunt the tracheal stimulation from ETT once thrown into prone +\- MEPs firing as others have said.

I certainly wouldn't tell the patient it was a seizure, I'd explain some movement that was interpreted as possible seizure but unlikely based on the anesthetic agents she was administered, most of which increase the seizure threshold.

 

[jwk]

Once again, proof literally nobody, even other physicians, including neurology/surgery have any clue what we do or how we do it.

Not sure how long between induction and flipping, likely 15min if anything like our neuro monitoring prone cases so propofol likely mostly gone but 1.8 sevo should be plenty. 50mcg fent and 100mg sux seems light to me though. I'd wager not enough to blunt the tracheal stimulation from ETT once thrown into prone +\- MEPs firing as others have said.

I certainly wouldn't tell the patient it was a seizure, I'd explain some movement that was interpreted as possible seizure but unlikely based on the anesthetic agents she was administered, most of which increase the seizure threshold.

No reason not to give a normal or near-normal intubating dose of roc in these patients. You've got to get them tubed, sometimes place an a-line or 2nd IV, flip and position, prep, drape, etc. Unless you're really fast, that's an easy 20-30 minutes in most places. The roc will be largely gone by the time your neuro-tech gets everything hooked up (and if you/they are worried, it can be reversed). And 50mcg of fentanyl on a 100kg patient is not gonna do much. As one of my old mentors used to say - "put em to sleep son".

 

[PainDrain]

While I think the most likely scenario is that the patient was light, I have seen significant myoclonus with propofol. I also had one patient who had jerking motions in the PACU post-op for almost two hours after GA. She reported that this happened anytime she had propofol and it lasted 24 hours. It looked like a combo of Parkinson's and seizure activity.

 

[chocomorsel]

Yup. Those squiggly lines mean something.

I just asked my neuromonitoring guy and he says that not all machines are capable of monitoring EEG. It depends on the computer make.

 

[Planktonmd]

Yes... Propofol induced myoclonic movements is my bet, it can have delayed onset and last for days sometimes.

 

[Pooh & Annie]

While I think the most likely scenario is that the patient was light, I have seen significant myoclonus with propofol. I also had one patient who had jerking motions in the PACU post-op for almost two hours after GA. She reported that this happened anytime she had propofol and it lasted 24 hours. It looked like a combo of Parkinson's and seizure activity.

Ditto. VIOLENT jerking motions every 2-3 minutes post-op, decreasing in frequency and severity over several hours. Pt is oriented in between but VERY lethargic. NO clonus DURING the procedure, only after.

I see pretty powerful myoclonus from propofol frequently enough, but it usually fades within 10 mins or so. This is the period where everyone looks at me like "what'd you do?!" Other than the one patient, I've never seen it carry over into recovery.

 

[eggscal99]

Next time don't confuse getting baseline MEPs as seizure activity. You're welcome.

that was my very first thought, but the neuromonitoring tech claimed that she hadn't started baseline MEPs yet, so who knows?

 

[chocomorsel]

No reason not to give a normal or near-normal intubating dose of roc in these patients. You've got to get them tubed, sometimes place an a-line or 2nd IV, flip and position, prep, drape, etc. Unless you're really fast, that's an easy 20-30 minutes in most places. The roc will be largely gone by the time your neuro-tech gets everything hooked up (and if you/they are worried, it can be reversed). And 50mcg of fentanyl on a 100kg patient is not gonna do much. As one of my old mentors used to say - "put em to sleep son".

Our surgeons and therefore us, are really fast. I have given as little as 20mg and have had to reverse them since the quality of the twitches was too poor for the Neuromonitoring technicians. So I just learned to intubate with a bunch of propofol. And chase it sometimes with phenylephrine in the old folks.

 

[chocomorsel]

Our surgeons and therefore us, are really fast. I have given as little as 20mg and have had to reverse them since the quality of the twitches was too poor for the Neuromonitoring technicians. So I just learned to intubate with sometimes bunch of propofol. And chase it sometimes with phenylephrine in the old or sick folks.

 

[eggscal99]

No reason not to give a normal or near-normal intubating dose of roc in these patients. You've got to get them tubed, sometimes place an a-line or 2nd IV, flip and position, prep, drape, etc. Unless you're really fast, that's an easy 20-30 minutes in most places. The roc will be largely gone by the time your neuro-tech gets everything hooked up (and if you/they are worried, it can be reversed). And 50mcg of fentanyl on a 100kg patient is not gonna do much. As one of my old mentors used to say - "put em to sleep son".

thanks for the input. I think coming out of training in a new

No reason not to give a normal or near-normal intubating dose of roc in these patients. You've got to get them tubed, sometimes place an a-line or 2nd IV, flip and position, prep, drape, etc. Unless you're really fast, that's an easy 20-30 minutes in most places. The roc will be largely gone by the time your neuro-tech gets everything hooked up (and if you/they are worried, it can be reversed). And 50mcg of fentanyl on a 100kg patient is not gonna do much. As one of my old mentors used to say - "put em to sleep son".

thanks for the input. I think coming out of training into a new practice I'm always afraid of stepping on someone else's foot and screwing things up. But you're right. the roc would've been gone after flipping and draping.
I've been giving less narcotic before incision, mainly because I hate the period of hypotension after induction and before incision; I can titrate the gas but the fentanyl takes time to wear off.

 

[eggscal99]

I wouldn't say that. I would play along, but for the next ones make sure they are deep.

so I talked to the pt after she woke up, explained thoroughly what happened. I told her all the seizure w/u has been negative, and I told her that the neurologist was calling it new onset seizure likely because it was like a witness event (or so we thought it was a seizure), but not so much that there was any diagnostic proof of actual seizure. I told her it could be seizure or that she was simply bucking. I told her the medications used for anesthesia were used quite commonly, and very rarely cause seizure. In fact, she had general anesthesia before, had received propofol sedation as well as local anesthetic for epidural injections without issue. I told her we took her to the ICU out of abundance of caution, and I told her I was glad that all the seizure/stroke w/u had been negative. She appeared satisfied with the discussion.

 

[eggscal99]

Good for the neurologist... now no matter what anyone says she'll insist that whatever elements of GA she got that day causes seizures. Probably'll carry a copy of the record just to make sure someone doesn't do it again.

neurologist wrote in note: "Ancef is known in some patients to induce seizure." I learn something new everyday.

 

[Orin]

No one drew a prolactin for academic purposes?

 

[CopaceticOne]

neurologist wrote in note: "Ancef is known in some patients to induce seizure." I learn something new everyday.

I was taught that is a patient with hx of seizure, high dose ancef, and possibly renal impairment.

 

[chessknt]

General anesthesia would be the last salvage treatment for intractable seizure so in someone who has never had a seizure--this wasn't a seizure.

The incidental neuro finding of intracranial athero is more important to her health than this stupid label--make sure they start her on a high dose statin and screen for CAD too. If she gets a huge MCA stroke 3 years from now and wasnt on a statin and the family is of the suing mindset that would be actionable, especially because it would convert to a big ol hemorrhage on her plavix/coumadin.

 

[Ronin786]

thanks for the input. I think coming out of training in a new


thanks for the input. I think coming out of training into a new practice I'm always afraid of stepping on someone else's foot and screwing things up. But you're right. the roc would've been gone after flipping and draping.
I've been giving less narcotic before incision, mainly because I hate the period of hypotension after induction and before incision; I can titrate the gas but the fentanyl takes time to wear off.

I'm only a resident but why don't you give more blue and less of the white stuff? For a lumbar laminectomy, 250-500mcg of fentanyl, 100mg of propofol and 0.5 MAC of gas is a nice start while you're getting flipped. Especially in someone who's not that old. And since the fentanyl is going to last a while, you don't have to run their gas very high and pressures will be much smoother. It's a pet peeve of mine, but I hate when attendings say they're worried about taking pressures but then slam a stick of propofol and blast the gas all the way.

Also I've seen this happen twice. None of my attendings were ever really able to explain it and I couldn't find any specific mention in books. But I've seen generalized shaking that is usually short lived and disappears. Maybe some sort of shivering or response to light anesthesia. The jerky leg movements after surgery are interesting though.

 

[ranvier]

One MRI is worth a whole room full of neurologists....

 

[epidural man]

People are pretty sure that it wasn't a seizure. I don't disagree...and probably would agree and say the same thing.

On the other hand, very strange things happen on rare occasion when we mess with physiology using very powerful drugs that we don't really understand and even if the incidence is one in a million, it is "one."

Maybe it was seizure?

It doesn't change anything about treatment or how you would change your world view on delivering anesthetic care.