Isobaric bupivacaine spinal for CS

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osoprop28

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Due to shortage of hyperbaric, we've had to switch over to isobaric bupivacaine (0.5%) for CS. And there's been more incidences of either failed spinal or high spinal causing HD instability.

Any tips you guys have for using isobaric in parturients? I was always taught to not lay them flat as suddenly as this can induce high spinal due to sudden shift in CSF, but any other method you guys use when using isobaric compared to hyperbaric? thanks!

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High spinal with isobaric? Don’t lay them flat as suddenly?

Isobaric shouldn’t move cephalad nearly as quickly as hyperbaric and is unlikely to give a high spinal or HD instability unless you are using a whopping dose. One of the benefits I have found using iso for hips in the elderly is you don’t typically see much of a sympathectomy.
 
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What dose? You really shouldn’t be seeing isobaric move cephalad as much. Isobaric takes longer to setup and lasts longer for equivalent dosage. The time to setup makes it not a great use for CS in my opinion.
 
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Yeah I thought the whole point of using isobaric was so that you could essentially put the patients headfirst into a centrifuge after placing the spinal and not really have issues.

Maybe I should do a study.

Any volunteers?
 
We switched over to isobaric for all of our total joints a few years ago. We found it to be more stable and predictable.

When I researched it before, there were some studies that basically said it worked well for CSxns, just need to use the same milligram dose as you would with hyperbaric
 
Yeah I thought the whole point of using isobaric was so that you could essentially put the patients headfirst into a centrifuge after placing the spinal and not really have issues.

Maybe I should do a study.

Any volunteers?
I would because I want to ride one of these things Rotor Ride Youtube

But I never want to have a spinal.

And to the conversation.

Edit to be helpful: I've done all my total joints/hip fractures (when I use a spinal) with 0.5% since residency. It's slightly hypobaric, but you still want to lay the person down, so it works great for hip fractures with the patient in lateral with the fracture site up. I've never seen a high spinal with it. I did a few c/s's with it when we had a hyperbaric shortage at my hospital. It just took a little longer to set up. I have seen some weird blocks that look a longer time to set up for joints -- contralateral leg set up first, so we induced general after waiting 20 minutes, by the time the surgery was done, the spinal was working.
 
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The answer is Heavy Bupivacaine with Epi. That will give you 2.5 hours of surgical time. If you can't do a C section in 2.5 hours then the issue isn't the Bupivacaine.

Slow Arse OB:

7.5% Bupivacaine (13-15 mg)
0.1 mg Epi
20 ug Fentanyl
200 ug Duramorph
( be prepared to give some pressors early)

I have never had one of those spinals last less than 2.5 hours.
 
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Due to shortage of hyperbaric, we've had to switch over to isobaric bupivacaine (0.5%) for CS. And there's been more incidences of either failed spinal or high spinal causing HD instability.

Any tips you guys have for using isobaric in parturients? I was always taught to not lay them flat as suddenly as this can induce high spinal due to sudden shift in CSF, but any other method you guys use when using isobaric compared to hyperbaric? thanks!
Failed Spinals? That's technique related. Zero failed spinals at my gig the past 2 years. HD instability? Again, bad technique with too much Heavy Bupivacaine- try lowering the dose to 10-12 mg Bupivacaine with early treatment of BP, even before the BP drops. I think you can't blame the drug for user error.

If you really prefer Isobaric Bupivacaine then you can order some Spinal dextrose to add to it and make your own Heavy Bupivacaine. I prefer the heavy stuff for OB because the block is denser and the motor block is much better. I have not had issues with HD instability with Isobaric Bupivacaine unless the dose is over 15 mg. Typically, 10-12 mg of Isobaric Bupivacaine should be enough for a C section but that can vary from shop to shop.



 
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1672949670166.png


Overall anesthetic success (success(operation)) ED50and ED95for isobaric intrathecal bupivacaine for cesarean delivery calculated from the logistic regression plot of probability of successful anesthesia versus dose of intrathecal bupivacaine.
 
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The incidence of intraoperative pain in the current study was very low (6%) with doses of 10 mg or greater, which is similar to our previous hyperbaric bupivacaine ED50/ED95study in which only 7% of patients reported intraoperative pain with doses larger than 10 mg.10In previous low-dose intrathecal bupivacaine studies for cesarean delivery, the incidences of visceral pain and discomfort using 5 and 8 mg were 50%1and 35%,9respectively. In another study, Petersen et al. 15found that increasing the intrathecal dose of bupivacaine from 7.5–10 to 10–12.5 mg decreased the incidence of pain associated with visceral traction from 70.5% to 31.6%, emphasizing the relation between larger doses and greater patient comfort. Differences in reported pain in these compared with the current investigation cannot be explained by the duration of surgery, uterine exteriorization, or use of adjuvant opioids, all of which were similar among the studies. Reducing the dose of local anesthetic in an attempt to decrease maternal hypotension may increase the likelihood of maternal discomfort and result in anesthetic failure in some patients. Such high incidences of intraoperative pain1,3,9suggest that anesthesia was suboptimal; such frequent discomfort would be considered unacceptable in our practice.
 
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The rate of vasopressor consumption between the groups and intra-operative maternal complications:

The rate of ephedrine requirement was relatively greater in the isobaric group 18 (36%) than the hyperbaric group 7 (14%) for the treatment of hypotension and it is statistically significant (p = 0.011). Nausea and vomiting were the most common maternal complications, which accounted for 44% in isobaric and 20% in hyperbaric groups of all complications. Relatively higher maternal complications were observed in with respect to nausea and vomiting, light headedness and respiratory depression in isobaric group. It was statistically significant between the groups (p = 0.001).

 
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The answer is Heavy Bupivacaine with Epi. That will give you 2.5 hours of surgical time. If you can't do a C section in 2.5 hours then the issue isn't the Bupivacaine.

Slow Arse OB:

7.5% Bupivacaine (13-15 mg)
0.1 mg Epi
20 ug Fentanyl
200 ug Duramorph
( be prepared to give some pressors early)

I have never had one of those spinals last less than 2.5 hours.

The issue for the OP is heavy bupi shortage not slow OBs. And that’s way too much duramorph.
 
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The incidence of intraoperative pain in the current study was very low (6%) with doses of 10 mg or greater, which is similar to our previous hyperbaric bupivacaine ED50/ED95study in which only 7% of patients reported intraoperative pain with doses larger than 10 mg.10In previous low-dose intrathecal bupivacaine studies for cesarean delivery, the incidences of visceral pain and discomfort using 5 and 8 mg were 50%1and 35%,9respectively. In another study, Petersen et al. 15found that increasing the intrathecal dose of bupivacaine from 7.5–10 to 10–12.5 mg decreased the incidence of pain associated with visceral traction from 70.5% to 31.6%, emphasizing the relation between larger doses and greater patient comfort. Differences in reported pain in these compared with the current investigation cannot be explained by the duration of surgery, uterine exteriorization, or use of adjuvant opioids, all of which were similar among the studies. Reducing the dose of local anesthetic in an attempt to decrease maternal hypotension may increase the likelihood of maternal discomfort and result in anesthetic failure in some patients. Such high incidences of intraoperative pain1,3,9suggest that anesthesia was suboptimal; such frequent discomfort would be considered unacceptable in our practice.
Years ago, our very busy women's hospital found the same. Sig more spotty blocks with 10.mg Bupivacaine. It was felt to be too few MG of local anesthetic to provide a complete nerve block. Isobaric is good for prone procedures, hemorrhoids, pilonidal cysts, fissures, etc.
 
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I am not arguing the effective dose of intrathecal morphine. I have seen 100 ug to 250 ug given. Many still use the 150 ug dosage routinely. I was listing 200 ug to boost the efficacy of the spinal opioid analgesic effect. I firmly believe 200 ug is within the standard of care even if your personal opinion is that dosage is "high."


Conclusions: This meta-analysis shows that HDs of intrathecal morphine prolong analgesia after cesarean delivery compared with lower doses.

HD= higher dose
 
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?

200 mcg is a completely reasonable dose. Better/longer analgesia than 100 mcg without significantly more side nausea/pruritis effects.

200 is no more effective than 100-150. Just more side effects.


Among others. Not a lot of time currently but happy to post more articles later if there’s a desire. I don’t think there are many high volume OB centers left giving more than 150mcg for post op pain after routine CS. I could be wrong as I don’t talk to everyone. But I talk to people who talk to most everyone haha.
 
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In the late 1990s, I had a partner who routinely gave 1mg IT MS for total knees. His patients actually did very well. Completely pain free and maybe too sleepy to notice any nausea and pruritus.
 
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200 is no more effective than 100-150. Just more side effects.


Among others. Not a lot of time currently but happy to post more articles later if there’s a desire. I don’t think there are many high volume OB centers left giving more than 150mcg for post op pain after routine CS. I could be wrong as I don’t talk to everyone. But I talk to people who talk to most everyone haha.
I ain't got no time for fancy peer-reviewed studies when I did one myself, back when I was less jaded by MOCA Part 4 nonsense ...


A massive N of 20+20, all spinalized by me. :) Going to keep on keepin' on with 200 mcg.


In all seriousness, the 100 vs 200 is really splitting hairs. It doesn't make enough of a difference to care about one way or the other.
 
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In the late 1990s, I had a partner who routinely gave 1mg IT MS for total knees. His patients actually did very well. Completely pain free and maybe too sleepy to notice any nausea and pruritus.

I've heard of demerol spinals for uro and now I wonder if you could do it for totals. I like mepi spinals for same day discharge.
 
200 is no more effective than 100-150. Just more side effects.


Among others. Not a lot of time currently but happy to post more articles later if there’s a desire. I don’t think there are many high volume OB centers left giving more than 150mcg for post op pain after routine CS. I could be wrong as I don’t talk to everyone. But I talk to people who talk to most everyone haha.
Even if there's a ceiling effect for analgesia, wouldn't a higher dose last longer?
 
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