Colonoscopy Case - thoughts?

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DrOwnage

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70 y/o female w/ a PMH of Idiopathic Pulmonary Hypertension (severe), HoTh, Raynauds presents for screening colonoscopy. Had an adenoma removed 7 years prior, GI and primary care want repeat colo. Patient states she is symptomatic with some blood on wiping and intermittent lower abdominal pain. SOB walking up one flight of stairs, able to do ADL, no c/p.

Meds: on amlodipine 5mg, bosentan 125 BID (recently uptitrated), tadalafil 40mg Qday, digoxin, furosemide 20mg qday

Last RHC 2012, PAP 90/30, MPAP 50, systemic pressure 102/70. Last six minute walk test 6 months ago - Spo2 84%, HR 134.

Echo 2017:
1. Normal LV size, mild septal hypertrophy, normal wall motion and systolic function.
2. Nomral LV diastolic function.
3. Left ventricular ejection fraction is approximately 60 to 65%.
4. Mildly enlarged right ventricular size and normal systolic function. (RV/LV ratio 0.83, fractional area change 36 %, TAPSE 2.5 cm, DTI 13.2 cm/s).
5. A prior echo performed on 11/15/2016 was reviewed for comparison. .
6. Mild left atrial enlargement.
7. Mitral sclerosis, with possible mild bileaflet valve prolapse. Mild mitral valve regurgitation.
8. Tricuspid regurgitant jet inadequate to assess pulmonary artery systolic pressure.

Has been scheduled twice in the past 2 years, first anesthesiologist wouldn't do it, second said it would be light sedation and patient would have to raise her hand when uncomfortable (patient refused and left the hospital). Patient called and told high risk of morbidity and death associated with her condition and anesthesia. Wants to proceed anyways due to symptoms and past cancellations.

Safest way to get her through?
 
Just do it. lady has normal RV. it's just lower colon. give a low dose propofol infusion. it looks like she isn't overweight based on history. you can even mix it up with precedex or ketamine if you want to.
if you are concerned, about giving any resp depressants, put in epidural and titrate slowly and keep pressures up
 
Just do it. lady has normal RV. it's just lower colon. give a low dose propofol infusion. it looks like she isn't overweight based on history. you can even mix it up with precedex or ketamine if you want to.
if you are concerned, about giving any resp depressants, put in epidural and titrate slowly and keep pressures up

Epidural for a colonoscopy?
 
If her most recent echo showed normal RV and an insignificant TR jet, her pulmonary hypertension has probably improved since 2012. If she is not symptomatic at rest, I would give some oxygen and propofol and not worry too much. She survived bowel surgery in 2011 and it seems her disease has not progressed.
 
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Would get a new echo (or do it yourself if comfortable) to make sure RV is still good, ensure shes compliant with diuretics, then proceed. NRB mask plus small bumps of ketafol until the scope is in. More important than the drug choices is just keep her ventilating since apnea -> hypercarbia -> RV failure is what kills these ppl
 
The lack of a TR jet and the NL-appearing RV are compelling in the context of her previous RHC numbers; perhaps her therapy is working. My experience has been hypercapnia and hypoxemia has been worse for these patients than the hemodynamic effect of positive pressure ventilation (although induction must be very careful). All things considered, I’d probably use prop or Midaz/fent; I see a lot of pacu hypotension with dex. I’d support her pressure aggressively with vasopressin to avoid RV ischemia.
 
What is hoth

Small prop bolus then low infusion. A good GI doc is key, don't want anyone messing around longer than they have to. Ketamine is a nice idea.
 
I’d support her pressure aggressively with vasopressin to avoid RV ischemia.

I've been told contradictory things regarding vasopressin with respect to coronary blood flow and subsequent myocardial perfusion, especially with bolus dosing of 0.5-1U. Why vasopressin here instead of another pressor like norepinephrine?
 
what's the life expectancy of a 70yo with severe PHTN?
Is she going to tolerate a bowel resection if she has a mass?
Is the bleeding on toilet paper haemorrhoids, or some other pathology that can be investigated with a flexi sigmoidoscopy?

is the procedure really necessary - I've had quite a few of these problem patients become a non issue after some pointed questioning of their GI doc.

If it's really in her interests to proceed ...
talk to her resp physician about optimisation for the procedure, then sedate carefully
 
I've been told contradictory things regarding vasopressin with respect to coronary blood flow and subsequent myocardial perfusion, especially with bolus dosing of 0.5-1U. Why vasopressin here instead of another pressor like norepinephrine?

Increased systemic pressure increases afterload which increases coronary perfusion. Too much afterload increases lvedp which decreases coronary perfusion.

Vasopressin increases systemic vascular but doesn't for pulmonary which is what you want.
 
Stuff that worsens PHTN: hypoxia, hypercarbia, and... pain (i.e. sympathetic stimulation). Also ketamine. 😉

I would probably use a well-titrated amount of fentanyl + versed (between 50/1 and 100/2), and a low-dose propofol infusion, just enough to keep her a touch deeper than "conscious sedation" (we don't want her to breathe less than during sleep). I would pre-hydrate her with 500-1000 ml of fluid, and maintain the diastolic pressure (because the RV likes it) and other vitals at about her baseline, with touches of vaso (although she may tolerate even just neo or nothing).

This is a MAC, people. Don't overcomplicate it. As long as one doesn't turn into a GA, it shouldn't be a big deal, because it can be stopped at any time. Most importantly: manage patient and GI expectations.
 
I've been told contradictory things regarding vasopressin with respect to coronary blood flow and subsequent myocardial perfusion, especially with bolus dosing of 0.5-1U. Why vasopressin here instead of another pressor like norepinephrine?
You are a resident, right?

The pulmonary circulation does not have V-1 receptors.
 
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I think he’s wondering if vaso can directly increase coronary artery tone and thereby decrease flow, offsetting the increased perfusion assumed by the increased systemic pressure. I don’t know the answer.
 
I think he’s wondering if vaso can directly increase coronary artery tone and thereby decrease flow, offsetting the increased perfusion assumed by the increased systemic pressure. I don’t know the answer.

Thanks for phrasing it more elegantly, but yes.
 
Stuff that worsens PHTN: hypoxia, hypercarbia, and... pain (i.e. sympathetic stimulation). Also ketamine. 😉

I would probably use a well-titrated amount of fentanyl + versed (between 50/1 and 100/2), and a low-dose propofol infusion, just enough to keep her a touch deeper than "conscious sedation" (we don't want her to breathe less than during sleep). I would pre-hydrate her with 500-1000 ml of fluid, and maintain the diastolic pressure (because the RV likes it) and other vitals at about her baseline, with touches of vaso (although she may tolerate even just neo or nothing).

This is a MAC, people. Don't overcomplicate it. As long as one doesn't turn into a GA, it shouldn't be a big deal, because it can be stopped at any time. Most importantly: manage patient and GI expectations.

how does ketamine worsen pthn? and is it even significant enough that you need to avoid it?
 
how does ketamine worsen pthn? and is it even significant enough that you need to avoid it?
My guess is through sympathetic stimulation. I don't know how significant it is. There are all those legends with ketamine, e.g. don't use it with increased ICP (false), don't use it in PTSD (false in low doses) etc.
 
1. What is HoTh??
2. This sounds like 50% of the patients we do on a daily basis.
3. How much do you think her ECHO has changed in a year? The 2017 ECHO said that they compared it to a 2016 ECHO, but didn't mention if anything got any worse. Talk to the patient, how bad are her symptoms?
4. My biggest concerns are whether they took their tadalafil in addition to their bowel prep. I'd load her up with a liter of fluid cause she's gonna be DRY AS A MOFO between NPO and bowel prep.

I'd do mAybe 1mg of versed and 1cc of fentanyl. Low doses of propofol. +/- small hit of ketamine 10mg at a time. It's a colonoscopy,should be 15-20 minutes. Tell the surgeon your concerns and maybe they can make it 10-15 minutes... Again keep it light and simple. She may remember things but that's what you gotta tell her if you do MAC/sedation. If she refuses, so be it...
 
I put these people on vasopressin infusions even for light sedation personally. And I place an arterial line even if it’s light sedation if the procedure (not the anesthesia, is associated with labile hemodynamics . Did a VT ablation in a patient like this recently
 
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Never done an art line for colonoscopy but crazier things have happened.

If you have non invasive continuous BP (nexfin ) this could be a good case for it.
 
I would use vasopressin continuously but not place an arterial line for a colonoscopy
 
Actual MAC, not mask GA with a jaw thrust MAC. Her RV is fine, keep her systemic pressure near her RHC numbers and she’s gonna be just fine. Most C-scopes are still done via light sedation, so she can get one with a little more than that.

I’m not worried about discomfort/pain so much, it’s not like these folks drop dead when they stub their toe at home. Hypotension PLUS hypoxia is where this goes poorly, otherwise she’s gonna be ok.
 
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Since the main problem is hypoventilation and hypotension, how about using a touch of Doxapram?

I have never used Doxapram. My rationale is theoretical.

Per Drugbank, Doxapram increases bp through cardiac output, not vasoconstriction. It is more prominent for hypovolemic patient. Isn't it great for this particular case?
 
Since the main problem is hypoventilation and hypotension, how about using a touch of Doxapram?

I have never used Doxapram. My rationale is theoretical.

Per Drugbank, Doxapram increases bp through cardiac output, not vasoconstriction. It is more prominent for hypovolemic patient. Isn't it great for this particular case?

what receptors does it target?
 
Doxapram? You guys are waaayyy overthinking this. So you'd rather use some drug you've never used before than just giving this poor lady some light sedation? The OP said that she can do ADLs but gets SOB with 1 flight of stairs. She is probably in that 2-4 MET category, but again she's getting a colonoscopy not a bowel resection. Titrate slowly, give her some TLC. KISS.
 
Thanks for the insight guys. Ended up doing a chem panel, potassium was 3.2 from the bowel prep; since it was MAC started peripheral KCL infusion and went forward. 1 of midazolam, 25 of fentanyl to start. 200mL bolus prior to starting. Asked GI doc to dilate with saline rather than CO2, brady'd down at one point to 40 BPM when scope first went in, but pressures held the entire time. Propofol at 50/min, titrated in 75 more of fentanyl throughout the case. Did great.
 
Doxapram? You guys are waaayyy overthinking this. So you'd rather use some drug you've never used before than just giving this poor lady some light sedation? The OP said that she can do ADLs but gets SOB with 1 flight of stairs. She is probably in that 2-4 MET category, but again she's getting a colonoscopy not a bowel resection. Titrate slowly, give her some TLC. KISS.

No kidding. Give a little propofol or ketamine or whatever, maybe a little vasopressin - whatever floats your boat.
 
Hypothyroid? Not an abbreviation I've seen before.
I f’in hate nemonics.
The pharmaceutical companies use them like they know what they are talking about and to make normal ****e sound more serious. OIC. WTF!,!! Stop taking your f’in narcotics and you won’t be so damn constipated. Only Americans would need another drug to treat the side effects of the drug they don’t need in first place.
 
Nobody does a decent scope in 10 minutes.

6 min withdrawal is the standard of care. 4 min is longer than our average cecal time. Lots of high quality negative scopes take ~10 min. Our ADR as a group is 43% so I know we are “decent.”

The indication here is bleeding not adenoma follow up (guidelines likely 5-10 years and I would go 10 every time in someone like this but now she’s in the window and bleeding...so I think we’re stuck scoping). I’d try unsedated w water immersion or lightly sedated at most.
 
From
Since the main problem is hypoventilation and hypotension, how about using a touch of Doxapram?

I have never used Doxapram. My rationale is theoretical.

Per Drugbank, Doxapram increases bp through cardiac output, not vasoconstriction. It is more prominent for hypovolemic patient. Isn't it great for this particular case?

From a purely hypothetical, and academic standpoint this sounds interesting. Stimulates resp drive which in theory helps you from developing hypercarbia in this Pt. Also supposedly increases cardiac output and has a small pressor effect, apparently more so in hypovolemic conditions. So again, in theory this is “perfect” for this patient. Except, that surely means an increase in HR and is mediated by an increase in catecholamines which isn’t exactly what you want in someone who you’re afraid has a weak RV paired with pulmonary HTN that you’re trying to maintain a good balance of systemic pressure, low PVR, and low myocardial O2 demand.

And I agree with whoever said that’s like needing a drug for a side effect of another drug here. You don’t need that if you don’t overdo your propofol. Use less, not more here. Her RV is decent, so she is a relatively easy one. But even with a worse RV the answer is still light MAC or light sedation only. With pulmonary hypertension and a failing RV you go very light, or very deep and control everything and for a C-scope the answer is almost always to lean towards light to nothing in my humble opinion.
 
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