Phentermine - no go for GA?

[SitraAchra]

Just wanted peoples' opinions on this.

I recently cancelled a case for an MRI in a claustrophobic patient with Stage 4 ESLD and CHF who was taking Phentermine as a diet drug. I've heard stories that it can lead to dysautonomia/intractable hypotension and I didn't want to risk it in an elective case in a sick patient.

Anyone have experience dealing with this?

I told the patient to stop taking it for a week and come back for the MRI.

What are your thoughts on what to do with a patient taking Phentermine?

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[narcusprince]

Why did the patient need general anesthesia for the mri? Why not mac sedation ? What was the mri for? I would have talked to the patient and sedated with midazolam or low dose propofol infusion if GA not needed.

 

[SitraAchra]

Why did the patient need general anesthesia for the mri? Why not mac sedation ? What was the mri for? I would have talked to the patient and sedated with midazolam or low dose propofol infusion if GA not needed.

Patient was obese and OSA, also wanted to be "deeply asleep" and the MRI was a total spine so C/T/L which is ~2.5hrs. I didn't want to have to wait for her to wiggle around and force the rad tech to pause the MRI for me to give her more blue and orange while risking her airway.

Any concern for propofol infusion in someone with a low native BP due to ESLD on a sympathomimetic even if not gas?

 

[Noyac]

You cancelled based on stories?

 

[WholeLottaGame7]

Just wanted peoples' opinions on this.

I recently cancelled a case for an MRI in a claustrophobic patient with Stage 4 ESLD and CHF who was taking Phentermine as a diet drug. I've heard stories that it can lead to dysautonomia/intractable hypotension and I didn't want to risk it in an elective case in a sick patient.

Anyone have experience dealing with this?

I told the patient to stop taking it for a week and come back for the MRI.

What are your thoughts on what to do with a patient taking Phentermine?

Why are they getting a CTL spine? Their upcoming C7-S2 fusion? /sarcasm

How ascitic/fluid overloaded are they? I'd probably RSI/ETT this person, also, if they look like I imagine they look. I don't care about the phentermine as much as I do the stage 4 ESLD and the CHF. I also don't care about 2.5 hrs of a propofol infusion, either, though tubing them makes it a moot point.

 

[caligas]

Just wanted peoples' opinions on this.

I recently cancelled a case for an MRI in a claustrophobic patient with Stage 4 ESLD and CHF who was taking Phentermine as a diet drug. I've heard stories that it can lead to dysautonomia/intractable hypotension and I didn't want to risk it in an elective case in a sick patient.

Anyone have experience dealing with this?

I told the patient to stop taking it for a week and come back for the MRI.

What are your thoughts on what to do with a patient taking Phentermine?

It has been anecdotally associated with severe HYPERtension with GA. 14 days is a conservative approach for elective procedures.

 

[Planktonmd]

Just wanted peoples' opinions on this.

I recently cancelled a case for an MRI in a claustrophobic patient with Stage 4 ESLD and CHF who was taking Phentermine as a diet drug. I've heard stories that it can lead to dysautonomia/intractable hypotension and I didn't want to risk it in an elective case in a sick patient.

Anyone have experience dealing with this?

I told the patient to stop taking it for a week and come back for the MRI.

What are your thoughts on what to do with a patient taking Phentermine?

It's not worse than Cocaine, so think how many people on Cocaine never tell you and you end up giving them anesthesia safely.

 

[vector2]

Patient was obese and OSA, also wanted to be "deeply asleep" and the MRI was a total spine so C/T/L which is ~2.5hrs. I didn't want to have to wait for her to wiggle around and force the rad tech to pause the MRI for me to give her more blue and orange while risking her airway.

Any concern for propofol infusion in someone with a low native BP due to ESLD on a sympathomimetic even if not gas?

Precedex/ketamine/glyco with nasal trumpet or oral airway covered in lidocaine jelly if needed. Phenylephrine gtt / IM ephedrine prn if bp drops. Tube if they have severe pulmonary hypertension and/or 10L of ascites.

 

[SitraAchra]

You cancelled based on stories?

Some call them case reports, but yes, stories.

It's not worse than Cocaine, so think how many people on Cocaine never tell you and you end up giving them anesthesia safely.

True, cocaine is worse. If a patient said they had been taking cocaine up until that day I would be inclined to cancel as well, but I am sure we all take care of people on coke with no issue.

Precedex/ketamine/glyco with nasal trumpet or oral airway covered in lidocaine jelly if needed. Phenylephrine gtt / IM ephedrine prn if bp drops. Tube if they have severe pulmonary hypertension and/or 10L of ascites.

That's some sexy anesthesia. How would you dose the precedex/ketamine - do you have infusion pumps that are MRI compatible or would you just titrate to effect the old fashioned way?

Sounds like I was on the conservative side of things to this forum, which is fine. Has anyone actually taken care of someone actively taking Phentermine? Just curious.

 

[pgg]

It's not worse than Cocaine, so think how many people on Cocaine never tell you and you end up giving them anesthesia safely.

Sure, but you're not going to take someone to the OR for elective surgery if they TELL you they're on the downslope of a cocaine binge, are you?

Or if someone TELLS you they just ate a ham sandwich?

OP's asking if you'd do this elective case, given that the patient TOLD him he was on this drug.


I would do this case; it's an MRI, not something that's going to have any risk for blood loss, fluid shifts, pain or really any physiologic stress at all. I'd have a direct-acting vasopressor available (as I always do for any case) and be aware that the patient may need it.

 

[Mman]

You cancelled based on stories?

many (most?) academic departments with guidelines you can find online recommend delaying elective surgeries in patients on phentermine for anywhere from 2-7 days. The concern isn't hypertension, it's severe hypotension from depleted catecholamines.

Is it a huge risk? No. But it's a risk. I've seen it and had to admit a patient unexpectedly because of it.

 

[SitraAchra]

Sure, but you're not going to take someone to the OR for elective surgery if they TELL you they're on the downslope of a cocaine binge, are you?

Or if someone TELLS you they just ate a ham sandwich?

OP's asking if you'd do this elective case, given that the patient TOLD him he was on this drug.


I would do this case; it's an MRI, not something that's going to have any risk for blood loss, fluid shifts, pain or really any physiologic stress at all. I'd have a direct-acting vasopressor available (as I always do for any case) and be aware that the patient may need it.

My thought process was, do I want to keep running into the MRI room and interrupting the scan to bolus phenylephrine to mess with hypotension, thus prolonging the procedure? Sick people get MRIs under sedation/GA frequently and putting someone on a phenylephrine drip isn't something new to me. My issue was the unkown effect of phentermine - how hypotensive would she be and how much of a pain in the @ss would it be to keep her pressures up? In someone with multi-organ system damage already underway, I found this risk to be excessive for a simple MRI that can easily be put off a week.

Further, one of the other hospitals I work at does have a "no phentermine for 7 days" policy. If this was a healthy young patient I would be more inclined to give it a shot, but the confluence of issues caused me to postpone it (I'll stop saying cancel, sounds too harsh).

 

[pgg]

I don't think it was unreasonable to cancel/postpone, especially if the hospital or group had a policy or guidelines.

For an MRI, running 1/2 a MAC of volatile or thereabouts, I wouldn't expect significant hypotension. If it did I'd expect a light phenylephrine infusion to handle it. Worst case, is I sit in the scanner with earplugs for a couple hours.

 

[Planktonmd]

Sure, but you're not going to take someone to the OR for elective surgery if they TELL you they're on the downslope of a cocaine binge, are you?

Or if someone TELLS you they just ate a ham sandwich?

OP's asking if you'd do this elective case, given that the patient TOLD him he was on this drug.


I would do this case; it's an MRI, not something that's going to have any risk for blood loss, fluid shifts, pain or really any physiologic stress at all. I'd have a direct-acting vasopressor available (as I always do for any case) and be aware that the patient may need it.

No you missed my point!
I said you take care of people on Cocaine probably more frequently than you know although Cocaine is most likely worse than diet drugs, and also you probably don't think twice about taking someone to the OR who is on Amphetamine derivatives for ADHD and those patients usually TELL you that they are taking it.
So, it's a bit silly to demand that they stop their diet drugs while it's OK for them to take ADHD drugs, that's what I meant!

 

[Planktonmd]

True, cocaine is worse. If a patient said they had been taking cocaine up until that day I would be inclined to cancel as well, but I am sure we all take care of people on coke with no issue.

How about patients taking Amphetamines for ADHD? Do you make them stop their ADHD medications for 7 days for an MRI?

 

[SitraAchra]

How about patients taking Amphetamines for ADHD? Do you make them stop their ADHD medications for 7 days for an MRI?

Nope, ADHD meds don't concern me. I understand the issue here, but if certain hospitals had a policy against Ritalin as they do Phentermine I would likely treat it the same way.

Now, do we know if ADHD meds pose less issue with BP than Phentermine? I don't know the answer to that. Like I said, it sounds like I was more conservative than most on how to handle this, and I'm fine with that. I'm 2 years out of residency so this is my "getting my bearings" period where I figure out my boundaries. Anyhow, thanks to all for the replies.

 

[pgg]

No you missed my point!
I said you take care of people on Cocaine probably more frequently than you know although Cocaine is most likely worse than diet drugs, and also you probably don't think twice about taking someone to the OR who is on Amphetamine derivatives for ADHD and those patients usually TELL you that they are taking it.
So, it's a bit silly to demand that they stop their diet drugs while it's OK for them to take ADHD drugs, that's what I meant!

I agree that these things are likely no big deal and we surely care for people who are currently/recently intoxicated all the time.

ARBs are probably worse than phentermine with regard to refractory hypotension, but does anybody cancel cases if patients took their ARB that morning? I hope not.

I'm just saying the legal risk calculus changes if we KNOW they're on these drugs, if our department or facility has an explicit written policy concerning them. I occasionally find myself adhering to department guidelines I don't really agree with, just because the hassles of a un-unified front and inconsistent stances within my department are greater than the hassle of doing or not doing a case. These are not battles I choose to fight, most of the time. Life's too short to bang your head against some of these walls.

 

[Pooh & Annie]

I think cancelling is totally reasonable. We're already making a very safe imaging test multiple times more dangerous by performing anesthesia on a sick person remote from the OR. In a CHF pt with PRESUMABLY lowered EF we're going to potentially give a boat load of pressor? What does their output look like then? Or do you give an inotrope? Phentermine increases synaptic catecholamines, and the pt has liver failure and probably very low MAO reductase levels. How will they tolerate a peri procedural dysrhythmia?

I'm not saying I WOULDN'T do it, because I don't know the whole story. And despite what I said, they will most likely do just fine. But I don't for a second blame someone for questioning the appropriateness of going forward with a completely elective case like this.

 

[Noyac]

Here's an approach I wish more newer ANESTHESIOLOGISTS would pursue. Next time you want to "postpone" or cancel a case for some reason, why not run it by one of your senior partners.
When people come out of training they frequently are rigid in their approach and get defensive. To others, it comes across as indecisive. This is a bad way to introduce yourself to a new community. Never hesitate to get a second opinion. Check your ego at the door. You will have plenty of opportunity in the future to stand your ground when you have established yourself after a few years in the trenches.

This is meant to be a general statement for the general population and has little to do with this case.

 

[narcusprince]

Agreed if your hospital has a policy then follow it. If not do the case and discuss with the patient doing it with Mac level sedation. If GA is warranted reschedule the case 7-14 days out.

 

[ZzzPlz]

Tell them you're busy and the ordering provider should try some Valium instead.

 

[SitraAchra]

Here's an approach I wish more newer ANESTHESIOLOGISTS would pursue. Next time you want to "postpone" or cancel a case for some reason, why not run it by one of your senior partners.
When people come out of training they frequently are rigid in their approach and get defensive. To others, it comes across as indecisive. This is a bad way to introduce yourself to a new community. Never hesitate to get a second opinion. Check your ego at the door. You will have plenty of opportunity in the future to stand your ground when you have established yourself after a few years in the trenches.

This is meant to be a general statement for the general population and has little to do with this case.

I totally agree with this. I in fact did call the chief of anesthesia at the facility I was at prior to cancelling this case, just to make sure I wasn't being overly conservative. Any type of "soft call" scenario like this I will contact a senior anesthesiologist for advice - it's always a good idea to get another perspective.

 

[Urzuz]

Precedex/ketamine/glyco with nasal trumpet or oral airway covered in lidocaine jelly if needed. Phenylephrine gtt / IM ephedrine prn if bp drops. Tube if they have severe pulmonary hypertension and/or 10L of ascites.

Sorry, this sounds like a nightmare plan for a 2.5 hour MRI in a dude with obesity, OSA, ESLD, etc. And I usually don't make a habit of sliding nasal trumpets in patients with ESLD but that's just me...

This is the type of guy that I either give nothing to (a mg or two of midazolam and nothing else), or he goes out all the way. Anything in between is just asking for 2.5 hours of hell.

Based on the patient's preferences, GA with an ETT is the way to go for this patient 100%. Don't know enough about the diet supplement to comment.

 

[nimbus]

ARBs are probably worse than phentermine with regard to refractory hypotension, but does anybody cancel cases if patients took their ARB that morning? I hope not.

No. But I've regretted not cancelling them a few times.

 

[IlDestriero]

I don't think it was unreasonable to cancel/postpone, especially if the hospital or group had a policy or guidelines.

For an MRI, running 1/2 a MAC of volatile or thereabouts, I wouldn't expect significant hypotension. If it did I'd expect a light phenylephrine infusion to handle it. Worst case, is I sit in the scanner with earplugs for a couple hours.

Don't your scanners have a pass through for infusion lines? RSI, start a phenylephrine infusion, .6 MAC volatile, titrate to effect from the control room.


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Il Destriero

 

[pgg]

Don't your scanners have a pass through for infusion lines? RSI, start a phenylephrine infusion, .6 MAC volatile, titrate to effect from the control room.

No, if we need to be in the room to do anything.

 

[Noyac]

No, if we need to be in the room to do anything.

You don't have an MRI compatible ventilator?
The pump issue is easy. Just hook up enough extension tubing sets to reach the back of the room or through the door.
You don't need a bunch of fancy equipment to do these cases.

Personally, I would have just sat in the room with a dirtbike magazine after convincing the pt that I would be there for any issues and that I would sedate her enough to be comfy but awake. Pts usually just want to know that you are giving them something. If this isn't the case here then off to dreamland she goes. What's the big deal?

 

[lobelsteve]

So why did they need a whole spine MRI? Would ask the ordering doc what they were looking for and how it would change treatment depending on what was found. A lot of risk and for what benefit? ACGME calls it system based practice. I'd have just yelled at the patient until they lay still or went to a different facility. Press ganey got nuttin on me.

 

[vector2]

Sorry, this sounds like a nightmare plan for a 2.5 hour MRI in a dude with obesity, OSA, ESLD, etc. And I usually don't make a habit of sliding nasal trumpets in patients with ESLD but that's just me...

This is the type of guy that I either give nothing to (a mg or two of midazolam and nothing else), or he goes out all the way. Anything in between is just asking for 2.5 hours of hell.

Based on the patient's preferences, GA with an ETT is the way to go for this patient 100%. Don't know enough about the diet supplement to comment.

I like the GA plan as well, but mostly just cause the scan is so long that babysitting a MAC that closely would be tiresome. I usually afrin squirt and downsize trumpets by one or two sizes d/t seeing some horrible epistaxis in the past, but obviously if this guys INR is 2.5 and plts are 50 I would go the oral route if needed. I work at one of the busiest liver transplant centers (and TAVR centers in which we do exclusively MACs) in the country, so I feel relatively comfortable providing pre- liver tx anesthesia for procedures which require more than versed/fentanyl and less than GA, and ime proper patient selection and judiciously titrated precedex and ketamine works like a charm.

 

[pgg]

You don't have an MRI compatible ventilator?
The pump issue is easy. Just hook up enough extension tubing sets to reach the back of the room or through the door.
You don't need a bunch of fancy equipment to do these cases.

Personally, I would have just sat in the room with a dirtbike magazine after convincing the pt that I would be there for any issues and that I would sedate her enough to be comfy but awake. Pts usually just want to know that you are giving them something. If this isn't the case here then off to dreamland she goes. What's the big deal?

Oh, we have Drager MRI compatible machines. I usually sit in the control room and watch the monitor through the window. But we don't have a way to adjust the vent or infusion pumps from the control room. Our MRI rooms have vault-like doors that seal like there's a nuclear nerve gas biohazard on the other side, so there's no way to string tubing to the patient from outside. If we need to make a change, we have to be inside.

 

[deleted162650]

Ours has a tiny hole drilled in the window to pass the narrow bore infusion tubing through