Fentanyl + morph in spinal anesthesia

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Sleeplessbordernights

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So this happened yesterda, C section, in a 22 year old 38 weeks preg otherwise healthy pt.

my attending said: you do everything, I’ll only intervene if something is wrong or the pt is in danger.

I used 8 mg heavy bupi, 25 mcg fent, 100 morph. Got a nice spinal, pt is stable, surgery went without any problem.

halfway trough my attending (young about 2 years ouf of residency) got relieved by another attendig (older, near retirement). I present the pt and the meds we used. He got very upset because in his words I should never mix spinal opioids, that I was lucky my pt was not vomiting and aspirating right now… anyway, i just rolled with the punches and finished the surgery.

Im pretty sure I can mix opioids to have a nice mix of post op pain relief and good visceral coverage in the surger, what do you think? Or what is your to go mix in spinals.
 
Just curious, how many c sections have you done so far in training? How many ml of the bupivicaine did you put in the spinal?
 
I'm in PP with some very quick surgeon (also some slow ones) and I tend to dose my spinals based on the chart from this paper (below). It works well as a dosing guide. I may chicken out and dose higher with slower surgeons though. Also I use 25 mcg fentanyl and 150 mcg duramorph.


Used to do 1.6 mL heavy bupi for everyone in residency. Lowest I've gone in PP is 1.3 mL. Never tried 1.2 mL!
 
I'm in PP with some very quick surgeon (also some slow ones) and I tend to dose my spinals based on the chart from this paper (below). It works well as a dosing guide. I may chicken out and dose higher with slower surgeons though. Also I use 25 mcg fentanyl and 150 mcg duramorph.


Used to do 1.6 mL heavy bupi for everyone in residency. Lowest I've gone in PP is 1.3 mL. Never tried 1.2 mL!

Don’t do OB these days, but just today I gave a tiny 75 year old, 50 kg lady 1 ml of hyperbaric bupi plus a whiff of fentanyl (10mcg) for a THA. I was working with a fast, predictable surgeon though.
 
How are you guys incorporating TAP blocks into your C- sections?
 
How are you guys incorporating TAP blocks into your C- sections?
Oh god

For a while they were the standard at my usual hospital. Everyone was encouraged to do them.

I rarely do OB there these days. I'd never do a TAP for a section if it was completely up to me, though next time I'm working L&D, I suppose I'll go along with it for the sake of "it's what we do here" and resident experience. For the rare section under general that didn't have an epidural, I guess there's a place for TAP blocks.
 
OP I've done IT fent+duramorph for CSs for a long time. It's silly not to. Your attendings need to get up to speed. 8mg is light IMO. I routinely use 1.6ml of heavy marcaine + 15mcg fent/100mcg duramorph, even in PP with fairly quick surgeons. I like good, solid dense blocks for patients staying awake during a CS.
 
It's fine. When I was a resident, our PD who was also the Director of OB anesthesia mixed the two all the time. The old timers haven't touched a book in years, probably don't even know where things are in the OR.
 
As far as TAP blocks for C sections…If they have an epidural then give epidural duramorph. If you do a spinal then give IT duramorph. Haven’t had issues with post op pain with that strategy. No TAP blocks required in my experience.
 
@Sleeplessbordernights, let this be a lesson for residency.

Step 1, figure out who has ridiculous and stringent methods and exaggerates the possible side effects to make you feel stupid (such as your second attending).
Step 2, do what these attendings say to avoid further conflict.
Step 3, realize deep down most of those types of personality are full of @#$%. Don't incorporate their practice into your future practice. Learn from another attending who is constructive and reasonable.
 
Oh god

For a while they were the standard at my usual hospital. Everyone was encouraged to do them.

I rarely do OB there these days. I'd never do a TAP for a section if it was completely up to me, though next time I'm working L&D, I suppose I'll go along with it for the sake of "it's what we do here" and resident experience. For the rare section under general that didn't have an epidural, I guess there's a place for TAP blocks.
Throw in the chronic opioid/pain patient. That's about it.
 
The most important thing about spinal opioids is billing the followup the next day.

if you care about that, just do the TAP/QL block in the OR. It collects way, way, way more $$$ than the follow up.
 
if you care about that, just do the TAP/QL block in the OR. It collects way, way, way more $$$ than the follow up.
Oh

Maybe that's why TAPs after sections are a thing.

How much more? I'm a billing newbie, having worked a salaried government job or hourly locums all my life.
 
Oh

Maybe that's why TAPs after sections are a thing.

How much more? I'm a billing newbie, having worked a salaried government job or hourly locums all my life.

i mean it depends on your contract, it might be worth more than you get paid for the csection
 
if you care about that, just do the TAP/QL block in the OR. It collects way, way, way more $$$ than the follow up.

Well I want to be somewhat ethical. Doing a tap block on a patient with an epidural just makes zero sense and has been shown to be useless.
 
So this happened yesterda, C section, in a 22 year old 38 weeks preg otherwise healthy pt.

my attending said: you do everything, I’ll only intervene if something is wrong or the pt is in danger.

I used 8 mg heavy bupi, 25 mcg fent, 100 morph. Got a nice spinal, pt is stable, surgery went without any problem.

halfway trough my attending (young about 2 years ouf of residency) got relieved by another attendig (older, near retirement). I present the pt and the meds we used. He got very upset because in his words I should never mix spinal opioids, that I was lucky my pt was not vomiting and aspirating right now… anyway, i just rolled with the punches and finished the surgery.

Im pretty sure I can mix opioids to have a nice mix of post op pain relief and good visceral coverage in the surger, what do you think? Or what is your to go mix in spinals.
Second anesthesiologist is an idiot, as we all suspect you already know.

Mix whatever you want, fent and duramorph have different onset times.

Also, aspiration or nausea are not common side effects of intrathecal opioids. In fact, intrathecal fentanyl actually decreases nausea during a C section as it covers some of the visceral pain incompletely covered by the block itself.

I agree 8 mg bup is a weird dose. Also, I only know doses of hyperbaric bup in mLs.

Also, 25 mcg of fent is slightly high, too much itching.
 
Also, aspiration or nausea are not common side effects of intrathecal opioids.
What? Nausea is one of the most common side effects of intrathecal morphine. Maybe not intraoperatively, but it is very common.
 
What? Nausea is one of the most common side effects of intrathecal morphine. Maybe not intraoperatively, but it is very common.
I have personally never seen significant nausea with 100-200 mcg of duramorph.
 
I have personally never seen significant nausea with 100-200 mcg of duramorph.

itching is far and away the most common side effect

Not sure what to tell you guys. Nausea is common after intrathecal opioid. That’s a fact. Google some studies and look at the percent of patients with nausea after having received intrathecal opioids if you don’t believe me.

Itching is common as well, but again, depending on what studies you look at, nausea can be even more common.
 
Not sure what to tell you guys. Nausea is common after intrathecal opioid. That’s a fact. Google some studies and look at the percent of patients with nausea after having received intrathecal opioids if you don’t believe me.

Itching is common as well, but again, depending on what studies you look at, nausea can be even more common.
I beleive nausea is a side effect, but I think it is rare with low dose neuraxial opioids. I have personally never had a non OB patient that got neuraxial opioids have nausea. I think the nausea is more likely from the major abdominal surgery and C section itself, but I have no evidence tj support my opinion.
 
I beleive nausea is a side effect, but I think it is rare with low dose neuraxial opioids. I have personally never had a non OB patient that got neuraxial opioids have nausea. I think the nausea is more likely from the major abdominal surgery and C section itself, but I have no evidence tj support my opinion.

I think it's from the obs tugging on the belly and the uterus like it owes them money
 
Not sure what to tell you guys. Nausea is common after intrathecal opioid. That’s a fact. Google some studies and look at the percent of patients with nausea after having received intrathecal opioids if you don’t believe me.

Itching is common as well, but again, depending on what studies you look at, nausea can be even more common.

what dose are you referring to? Low dose narcotic causes minimal nausea. IT morphine even at relatively low doses consistently causes itching.
 
what dose are you referring to? Low dose narcotic causes minimal nausea. IT morphine even at relatively low doses consistently causes itching.
Yes, people used to do much higher doses of intrathecal duramorph, and nausea was more common. I agree itching is the predominant and more likely side effect
 
Last I looked the data showed no real analgesic benefit but more side effects above 400 mcg intrathecal morphine.

I use 200 and see some itching but nausea is just about a never event - at least, I never see nausea that can plausibly be blamed on the IT morphine.

C-section nausea is all about the uterus yanking and hypotension (if you let that happen).
 
what dose are you referring to? Low dose narcotic causes minimal nausea. IT morphine even at relatively low doses consistently causes itching.

Yes, people used to do much higher doses of intrathecal duramorph, and nausea was more common. I agree itching is the predominant and more likely side effect

Last I looked the data showed no real analgesic benefit but more side effects above 400 mcg intrathecal morphine.

I use 200 and see some itching but nausea is just about a never event - at least, I never see nausea that can plausibly be blamed on the IT morphine.

C-section nausea is all about the uterus yanking and hypotension (if you let that happen).

Again, not sure what to tell you guys. The data out there doesn’t support your guys’ anecdotal experiences. I’m interested in seeing what studies you can show me that proves what you’re saying.

A few studies showing that IT morphine causes nausea / vomiting :

1) http://www.anestesiologiachp.com/DevPort/modules/dGC/files/artigosv/Risks and side-effects of intrathecal morphine combined.pdf

Meta analysis looking at side effects of intrathecal morphine. “In our analysis, patients receiving morphine < 0.3 mg in addition to spinal anaesthesia showed a significantly increased risk of nausea (RR = 1.4), vomiting (RR = 2.9), …”

2) Opioid-related side-effects after intrathecal morphine: a... : European Journal of Anaesthesiology | EJA

A study looking at nonsurgical patients who got IT morphine for pain relief, which showed doses as small as 15-30 mcg caused nausea and vomiting.

3) Another prospective study in joint arthroplasty showing increased rates of N/V:

Risk of postoperative nausea and vomiting in hip and knee arthroplasty: a prospective cohort study after spinal anaesthesia including intrathecal morphine - BMC Anesthesiology

“The main finding in our observational study in patients receiving intrathecal morphine was a high risk of PONV”

Another paragraph in the discussion for you guys to read: “The PONV risk found in our cohort are in accordance with previous studies. A meta-analysis evaluating intrathecal morphine (0.05–0.25 mg) in caesarean section found an overall PONV-risk of number needed to harm (NNH) of 6.3 for nausea and 10.1 for vomiting [5]. Another study investigating side effects in a randomized, double-blind, dose-response study concluded that nausea was present at even low doses of intrathecal morphine (0.015 mg) with an risk of 56% compared to a control group with a risk of 4% [6]. The absolute risks vary between studies and might be dependent on study settings and PONV prophylaxis, but many studies with intrathecal morphine report high risk for PONV”

Again, not all the highest quality studies/data, but it is surely better than an individual’s anecdotal experience, especially if you aren’t following up with each and every patient and specifically asking them about their symptoms...
 
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Another paragraph in the discussion for you guys to read: “The PONV risk found in our cohort are in accordance with previous studies. A meta-analysis evaluating intrathecal morphine (0.05–0.25 mg) in caesarean section found an overall PONV-risk of number needed to harm (NNH) of 6.3 for nausea and 10.1 for vomiting [5]. Another study investigating side effects in a randomized, double-blind, dose-response study concluded that nausea was present at even low doses of intrathecal morphine (0.015 mg) with an risk of 56% compared to a control group with a risk of 4% [6]. The absolute risks vary between studies and might be dependent on study settings and PONV prophylaxis, but many studies with intrathecal morphine report high risk for PONV”

Again, not all the highest quality studies/data, but it is surely better than an individual’s anecdotal experience, especially if you aren’t following up with each and every patient and specifically asking them about their symptoms...

so it causes maybe 15% more patients to be nauseated? I stand by my anecdotal evidence that it causes near 100% to be itchy, or in other words the far most likely side effect.

Also we both have 24 hour follow up with all c-section patients as well as MAR data on usage of meds for things like pain, nausea, and itching.
 
so it causes maybe 15% more patients to be nauseated? I stand by my anecdotal evidence that it causes near 100% to be itchy, or in other words the far most likely side effect.

Also we both have 24 hour follow up with all c-section patients as well as MAR data on usage of meds for things like pain, nausea, and itching.

1) I never objected to your statement that itchiness is more common in your experience. My exact quote was: "Itching is common as well, but again, depending on what studies you look at, nausea can be even more common." Look at above studies if you don't believe me.

2) The other posters who I kinda grouped with you have been saying things like "...aspiration and nausea are not common side effects of intrathecal opioids", "I beleive nausea is a side effect, but I think it is rare with low dose neuraxial opioids.", "I use 200 and see some itching but nausea is just about a never event". You yourself said "Low dose narcotic causes minimal nausea."

I have no idea what everyone's definitions of 'rare' and 'never event' are, but 15% (if you use the NNH you quoted), or the RR of 1.4 (40% more likely), or the rate of nausea being 56% in nonsurgical patients who got a spinal with 15 mcg of morphine...that doesn't seem as rare as everyone is making it out to be.

3) Several posters were blaming the nausea on the OBs yanking on the uterus, once again providing exactly zero evidence other than anecdote to prove that. It also doesn't explain why non-C-section patients commonly get nauseated after getting a spinal with morphine.

I have no idea what is with people and providing anecdote after anecdote to refute an evidence-based claim. It makes it very challenging to keep it scientific and factual. At least critique the study design of the studies I provided, or link another study that supports your claims...
 
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1) I never objected to your statement that itchiness is more common in your experience. My exact quote was: "Itching is common as well, but again, depending on what studies you look at, nausea can be even more common." Look at above studies if you don't believe me.

2) The other posters who I kinda grouped with you have been saying things like "...aspiration and nausea are not common side effects of intrathecal opioids", "I beleive nausea is a side effect, but I think it is rare with low dose neuraxial opioids.", "I use 200 and see some itching but nausea is just about a never event". You yourself said "Low dose narcotic causes minimal nausea."

I have no idea what everyone's definitions of 'rare' and 'never event' are, but 15% (if you use the NNH you quoted), or the RR of 1.4 (40% more likely), or the rate of nausea being 56% in nonsurgical patients who got a spinal with 15 mcg of morphine...that doesn't seem as rare as everyone is making it out to be.

3) Several posters were blaming the nausea on the OBs yanking on the uterus, once again providing exactly zero evidence other than anecdote to prove that. It also doesn't explain why non-C-section patients get commonly nauseated after getting a spinal with morphine.

I have no idea what is with people and providing anecdote after anecdote to refute an evidence-based claim. It makes it very challenging to keep it scientific and factual. At least critique the study design of the studies I provided, or link another study that supports your claims...
You must be new here. anecdotes>>>scientific studies
 
1) I never objected to your statement that itchiness is more common in your experience. My exact quote was: "Itching is common as well, but again, depending on what studies you look at, nausea can be even more common." Look at above studies if you don't believe me.

2) The other posters who I kinda grouped with you have been saying things like "...aspiration and nausea are not common side effects of intrathecal opioids", "I beleive nausea is a side effect, but I think it is rare with low dose neuraxial opioids.", "I use 200 and see some itching but nausea is just about a never event". You yourself said "Low dose narcotic causes minimal nausea."

I have no idea what everyone's definitions of 'rare' and 'never event' are, but 15% (if you use the NNH you quoted), or the RR of 1.4 (40% more likely), or the rate of nausea being 56% in nonsurgical patients who got a spinal with 15 mcg of morphine...that doesn't seem as rare as everyone is making it out to be.

3) Several posters were blaming the nausea on the OBs yanking on the uterus, once again providing exactly zero evidence other than anecdote to prove that. It also doesn't explain why non-C-section patients commonly get nauseated after getting a spinal with morphine.

I have no idea what is with people and providing anecdote after anecdote to refute an evidence-based claim. It makes it very challenging to keep it scientific and factual. At least critique the study design of the studies I provided, or link another study that supports your claims...
Fake news
 
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