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New SDN Article! Q&A with Dr. Maria Vasquez, Specialty Pharmacist
1st CHB= complete heart block? PPM=?
I am seeing more and more requests for this situation. ie where the patient is has multiple potential life threatening comorbities for an otherwise simple procedure. Although my altruistic side says they are calling us because they want the patient to have the best and safest sedation, my critical sides says that we are merely assuming liability for the medicine or radiology guy.
I would ask them how the study is going to change their management of the patient. Then i would ask them what there expectations are. If they want a GA w/o an airway in an MRI i would be more critical. Does the pt have a pacer?
On a side note i was once asked to provide sedation for an MRI for a patient with acute mental status changes and they were considering that patient may being having a CVA. I asked the ED physician who placed the consult if neurology felt comfortable with deep sedation in a patient with an unknown cerebral event. Neurology was not and the ed cancelled the consult.
I am seeing more and more requests for this situation. ie where the patient is has multiple potential life threatening comorbities for an otherwise simple procedure. Although my altruistic side says they are calling us because they want the patient to have the best and safest sedation, my critical sides says that we are merely assuming liability for the medicine or radiology guy.
I would ask them how the study is going to change their management of the patient. Then i would ask them what there expectations are. If they want a GA w/o an airway in an MRI i would be more critical. Does the pt have a pacer?
On a side note i was once asked to provide sedation for an MRI for a patient with acute mental status changes and they were considering that patient may being having a CVA. I asked the ED physician who placed the consult if neurology felt comfortable with deep sedation in a patient with an unknown cerebral event. Neurology was not and the ed cancelled the consult.
PPM?
a case like this happened at my home hospital, LOL in NAD who fell... ER doc wanted a CT to r/o bleed. I think they gave her some Ativan which bottomed her out and ended up with ischemic event/troponin spill/MI (cardiology said MI, the ER doc said troponin spill...can't remember the exact #). huge lesson for me to be super careful with the elderly and the benzos...
other wise -- discuss risks and benefits with patient and a family member if available...if really needs the MRI and can't relax i would use etomidate.
a case like this happened at my home hospital, LOL in NAD who fell... ER doc wanted a CT to r/o bleed. I think they gave her some Ativan which bottomed her out and ended up with ischemic event/troponin spill/MI (cardiology said MI, the ER doc said troponin spill...can't remember the exact #). huge lesson for me to be super careful with the elderly and the benzos...
other wise -- discuss risks and benefits with patient and a family member if available...if really needs the MRI and can't relax i would use etomidate.
PPM = permanent pacemaker
The question is whether to do an MRI on a patient whose life depends on a relatively delicate piece of electronics inside implanted metallic object.
My instinct is that there isn't any MRI finding that could meaningfully alter this guys outcome.
The question is whether to do an MRI on a patient whose life depends on a relatively delicate piece of electronics inside implanted metallic object.
My instinct is that there isn't any MRI finding that could meaningfully alter this guys outcome.
Doesn't the pacer disqualify this patient from an MRI?
Assuming it didn't matter, and assuming there are no other 'issues' I would load precedex and run a drip. Or just a low dose propofol infusion with a few boluses.
Generally yes. But it's been done, +/- disastrous complications. I think the issue isn't so much the pacemaker being ripped from the pocket as heating up and/or not working. (Not to mention degrading the images)
It's something you would consider if the patient had a life threatening problem that the MRI and MRI along might help manage.
I'd put the liability for proceeding on the radiologist and ordering doc -have them document the possibility of acquiring potentially lifesaving information and the inability to acquire it in a less risky fashion.
As for then anesthetizing the person, you need some reliable backup method if the pacer fries. Maybe place and confirm usability of a pacing swan which gives you the ability to detect and rescue CHB.
Cant put a swan in the MRI either. If it is absolutely essential (which it most likely isnt) that he needs an MRI, the pacer needs to be interrogated to see
1. Is he pacemaker dependent. Just because he was in complete block when it was put in doesnt mean he is now.
2. What happens when I put a magnet on it. Not that it really matters in this case since my magnet is going nowhere near the MRI which will probably mess up the pacer programming anyway.
If he actually isnt pacer dependent and needs the MRI, then deactivate the pacer do the MRI with whatever sedation works for you, and keep the crash cart with pacing pads close by. tell the MRI folks they may need to abort quickly. If not tell them to go to CT or PET for whatever they need the scan for.
by the way, some abbreviations are not standard practice for all areas/institutions and it doesnt take that long to type out most things. It would be appreciated if the conditions were spelled out in the future. This especially annoys me on notes on our pediatric patients when the peds guys use some f'd up abbreviation for a condition I've not read about since med school.
1. Is he pacemaker dependent. Just because he was in complete block when it was put in doesnt mean he is now.
2. What happens when I put a magnet on it. Not that it really matters in this case since my magnet is going nowhere near the MRI which will probably mess up the pacer programming anyway.
If he actually isnt pacer dependent and needs the MRI, then deactivate the pacer do the MRI with whatever sedation works for you, and keep the crash cart with pacing pads close by. tell the MRI folks they may need to abort quickly. If not tell them to go to CT or PET for whatever they need the scan for.
by the way, some abbreviations are not standard practice for all areas/institutions and it doesnt take that long to type out most things. It would be appreciated if the conditions were spelled out in the future. This especially annoys me on notes on our pediatric patients when the peds guys use some f'd up abbreviation for a condition I've not read about since med school.
Why do an MRI? We already know this guy has Lung Ca with mets. What information can the MRI tell us that a CT can't? On top of that, how would this information change our long term management of a guy who has a poor prognosis anyway?
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- Thread Starter
- #16
Why? what concerns you about GA without an airway assuming no risk factors and that patient meets NPO guidelines? Ever done a general anesthetic without an airway? If so what makes this one different?
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- Thread Starter
- #17
Pt is pacemaker dependent. Would you bring the crash cart into close proximity of the MRI?
doesn't the magnetic field of the mri disturb the function of the pacemaker that the pt is dependent on... mri won't add j.s. to the management of this patient...if he cannot tolerate the procedure sans pharmacology then no mri imho.
If this guy dies and I'm the anesthesiologist then I'll be sued so I'd at least like an explanation as to why I should put him under in the first place and what's going on. It's professional courtesy at a minimum and yes I'd prolly ask the question given that there significant risks associated w/sedation
Nope, its staying right outside the door though. Hence my remark to the MRI staff that we may need to abort QUICKLY and bring the patient out. Of course this was all dependent of the patient not being pacer dependent. Although, since the patient is pacer dependent that makes it a no dice for me on the MRI. Go to CT and make do.
This is completely elective procedure. Call cardiology/pacemaker company and see if they have any bright ideas since it is their piece of equipment. These things from my understanding can all quite differently depending on the type.
It's not a completely elective procedure. If it were, the answer is easy - cancel the MR. You would only consider this in a dire situation
The pacemaker company will say that a PPM is an absolute contraindication to MRI.
The material in the Swan-Ganz is either ferromagnetic or may melt. Im not sure if this is true of all PA catheters or just the ones with thermodilution CO capability. Im not sure about the pacing catheters either.
Threefold. One- the magnet could rip out a lead, leaving the patient to his own devices, so to speak. Two- the magnet could induce current in the pacer, affecting it's function. Three- the magnet could rip the damn thing right out of his chest! (probably least likely of the three, but sounds coolest)
Or the magnet would levitate the patient right off the table and the pacer would stick them to the side of the MRI machine.
I vote not to proceed. The team should be able to figure out a non-MRI modality to find whatever it is they are looking for with a reasonable degree of certainty.
I vote not to proceed. The team should be able to figure out a non-MRI modality to find whatever it is they are looking for with a reasonable degree of certainty.
Given my personal experience with radiology departments as an intern, i'm amazed that they are signing on as this even being a possibility. I would get a really clear statement of why this is medically necessary and how it will change management over a CT.
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- Thread Starter
- #28
Hey Guys: thanks for the responses. They were all great and I am glad this situation elicited some discussion.
The primary team decided to cancel the procedure for now and I learned that the way to handle this situation is to consult the electrophysiologist and let them determine whether you can proceed. If there are any complications, at least its on paper that the expert on pacemakers said it was ok to proceed.
The primary team decided to cancel the procedure for now and I learned that the way to handle this situation is to consult the electrophysiologist and let them determine whether you can proceed. If there are any complications, at least its on paper that the expert on pacemakers said it was ok to proceed.
- Aug 8, 2001
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Once I was in the MRI scanner and who of all people forgot to take something metallic out of their pocket but the tech herself. We were in there for a while positioning the pt. when a caught the briefest glimpse of an object go whizzing through the air. So things really do become missiles but it wasn't quite as earth shattering as some people make it out to be.
A Sampling of MRI Related Incidents from the MDR Database
* MDR-351516:
A patient with an implanted cardiac pacemaker died during an MR exam. (12/2/92)
* MDR-175218:
A patient with an implanted cardiac pacemaker died during or shortly after an MR exam. The coroner determined that the death was due to the interruption of the pacemaker by the MR system. (9/18/89)
MDR-349790:
A patient with an implanted intracranial aneurysm clip died as a result of an attempt to scan her. The clip reportedly shifted when exposed to the magnetic field. The staff apparently had obtained information indicating that the material in this clip could be scanned safely. (11/11/92)
MDR-100222:
Dislodgement of an iron filing in a patient's eye during MR imaging resulted in vision loss in that eye. (1/8/85)
MDR-454660:
A patient complained of double vision after an MR exam. The MR exam as well as an x-ray revealed the presence of metal near the patient's eye. The patient was sedated at the time of the exam and was not able to inform anyone of this condition. (12/15/93)
MDR-547886:
An IV pole was attracted to the magnet and struck a patient, cutting his arm. The patient required stapling of the cut. (8/30/94)
MDR-405200:
A pair of scissors was pulled out of a nurses hand as she entered the magnet room. The scissors hit a patient causing a cut on the patient's head. (8/2/93)
MDR-234698:
A patient was struck by an oxygen bottle while being placed in the magnet bore. The patient received injuries requiring sutures. (6/2/91)
PRP-19168:
Two steel tines (parts of a fork lift) weighing 80 pounds each were accelerated by the magnet striking a technician and knocking him over 15 feet resulting in serious injury. (6/5/86)
And of course this:
http://query.nytimes.com/gst/fullpage.html?sec=health&res=9D07EED7163DF93AA1575AC0A9679C8B63
Nothing to fool around with.
David Carpenter, PA-C