Ketamine for spines

[turnupthevapor]

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I am going to use this regimen (below) tomorrow. I wanted all of your input on the dose of ketamine (2 mg midazolam before leaving the preoperative holding area, 2–3
g/kg fentanyl before induction, 2–2.5 mg/kg propofol on induction, and isoflurane for maintenance of anesthesia....0.5 mg/kg ketamine on induction and an infusion of 10 micrograms /kg/min started before incision and terminated on closure of the incision.)

This seems like a LOT of ketamine and was wondering what your experiences with ketamine infusions during spines are.





Intraoperative Ketamine Reduces Perioperative Opiate
Consumption in Opiate-dependent Patients with Chronic
Back Pain Undergoing Back Surgery

ABSTRACT
Background: Ketamine is an N-methyl-D-aspartate receptor
antagonist that has been shown to be useful in the reduction
of acute postoperative pain and analgesic consumption in a
variety of surgical interventions with variable routes of administration.
Little is known regarding its efficacy in opiatedependent
patients with a history of chronic pain. We hypothesized
that ketamine would reduce postoperative opiate
consumption in this patient population.
Methods: This was a randomized, prospective, doubleblinded,
and placebo-controlled trial involving opiate-dependent
patients undergoing major lumbar spine surgery. Fifty-two
patients in the treatment group were administered 0.5 mg/kg
intravenous ketamine on induction of anesthesia, and a continuous
infusion at 10
gkg
1min
1 was begun on induction and
terminated at wound closure. Fifty patients in the placebo group
received saline of equivalent volume. Patients were observed for
48 h postoperatively and followed up at 6 weeks. The primary
outcome was 48-h morphine consumption.
Results: Total morphine consumption (morphine equivalents)
was significantly reduced in the treatment group 48 h
after the procedure. It was also reduced at 24 h and at 6
weeks. The average reported pain intensity was significantly
reduced in the postanesthesia care unit and at 6 weeks. The
groups had no differences in known ketamine- or opiaterelated
side effects.
Conclusions: Intraoperative ketamine reduces opiate consumption
in the 48-h postoperative period in opiate-dependent
patients with chronic pain. Ketamine may also reduce
opioid consumption and pain intensity throughout the postoperative
period in this patient population.

 

[G0S2]

I have tried this protocol out twice on spines and it seems to work well. Don't know about the pts post-op opiate use. Many of my faculty, however, do not go over 200MG of ketamine total.

 

[IlDestriero]

Here's what I do for spines (usually scoliosis as I practice 100% peds). Always a TIVA. (after mask induction)
Premed with oral midazolam and Tylenol.
Mask induction, IV, propofol bolus (2/kg) for intubation and 1 mcg/kg fentanyl.
Start infusions of propofol (200), remi (0.1), and ketamine (0.1 mg/kg/hr- very low dose). Volatiles off.
Lines in. 1 mg/kg ketamine before flip.
They also get 0.1 mg/kg of methadone at induction.
I skip the methadone in the really disabled neuromuscular kids, who also get amicar.
I can usually get the prop down to around 125 and the remi up to 0.2-0.3 when things settle down.

 

[Idiopathic]

my lumbar spines and uncomplicated cervical spines get ketamine infusion at 0.5mg/kg/hour (between 30-50mg/hour) during the case, which i turn down to 2mcg/kg/min (usually 6-10mg/hour), usually about 30 minutes before emergence, and this is continued until they leave PACU.

my sample size with this technique is fairly small (8-10 patients) but they have all been pretty comfortable, no one has been disoriented or problematic in recovery and there has been no delayed emergence.

i also like this as part of a balanced TIVA for MEP monitoring, which includes propofol, remi/su, lidocaine, ketamine infusions (sometimes will add precedex)

 

[Idiopathic]

I am going to use this regimen (below) tomorrow. I wanted all of your input on the dose of ketamine (2 mg midazolam before leaving the preoperative holding area, 2–3
g/kg fentanyl before induction, 2–2.5 mg/kg propofol on induction, and isoflurane for maintenance of anesthesia....0.5 mg/kg ketamine on induction and an infusion of 10 micrograms /kg/min started before incision and terminated on closure of the incision.)

This seems like a LOT of ketamine and was wondering what your experiences with ketamine infusions during spines are.

its not a lot. 10mcg/kg/min is 0.6mg/kg/hour which is consistent with what i use in any case where I will be using ketamine

 

[IlDestriero]

its not a lot. 10mcg/kg/min is 0.6mg/kg/hour which is consistent with what i use in any case where I will be using ketamine

I used to use 0.5mg/kg/hr, but have had good success (in scoliosis patients) with only 0.1 mg/kg/hr. Chronic pain patients may need higher doses to get the desired effect.
How about adding clonidine and magnesium to the recipe?

 

[BLADEMDA]

http://www.anesthesia-analgesia.org/content/100/2/475.full.pdf

I limit my total Ketamine for a case to 150-200mg. Take a look at the above study.

For Spines with Neuromonitoring I sometimes run a nice cocktail of Propofol with Ketamine mixed in, Sufenta or Fentanyl drip and no more than 1/2 MAC of Vapor. It's easy and works well.

For shorter cases I wouldn't run the Sufenta/Fentanyl drip.

 

[BLADEMDA]

http://books.google.com/books?id=-YI9P2DLe9UC&pg=PA1486&lpg=PA1486&dq=total+dose+of+ketamine+as+an+infusion+for+spinal+surgery&source=bl&ots=ch5kidA7S0&sig=iuyg_JWot4RMzNYHtptj-yZJLrA&hl=en&ei=cvVqTYTHCpDVgAeo_vnLCg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBMQ6AEwADge#v=onepage&q=total%20dose%20of%20ketamine%20as%20an%20infusion%20for%20spinal%20surgery&f=false


I don't add Clonidine because of concern for Hypotension in Lumbar Spine cases (Blindness). Precedex is expensive compared to GENERIC Iso/Propofol/Ketamine/Sufenta but I have no problem with it as it is easily titrated down/off if needed.

I am familiar with Lidocaine Infusions to decrease pain in Bowel Surgery cases but haven't seen good studies with it for Spine.


http://bja.oxfordjournals.org/content/early/2010/07/21/bja.aeq189.abstract
http://clinicaltrials.gov/ct2/show/NCT01043211

 

[Idiopathic]

its a medicine that i use and trust in many cases, most notably those cases where a TIVA is desirable as it has shown to be effective in decreasing the amount of propofol necessary to maintain anesthesia, so I will use it in anything from an ENT case to a spine. Its extremely safe, it augments the general anesthetic, it helps with the wakeup and with postop pain. I know its a slippery slope, but I feel comfortable using it for spines without any good RCT data.

 

[Idiopathic]

http://www.anesthesia-analgesia.org/content/100/2/475.full.pdf

I limit my total Ketamine for a case to 150-200mg. Take a look at the above study.

For Spines with Neuromonitoring I sometimes run a nice cocktail of Propofol with Ketamine mixed in, Sufenta or Fentanyl drip and no more than 1/2 MAC of Vapor. It's easy and works well.

For shorter cases I wouldn't run the Sufenta/Fentanyl drip.

that study has nothing to do with your arbitrary maximum aggregate ketamine dose.

 

[BLADEMDA]

Large doses of ketamine (>2 mg/kg) are associated with unacceptable psychotomimetic side effects (10). Common complaints include hallucinations, vivid dreams, cognitive decline, and emergence confusion (10). However, side effects are rare with a reduced dose of ketamine ranging from 0.15 to 0.5 mg/kg (10,25,26).


http://journals.lww.com/ejanaesthes...mine_with_clonidine_and_midazolam_for.14.aspx

 

[BLADEMDA]

Ninety-five percent of cases in this series were
performed with 200 mg or less total ketamine.


http://drfriedberg.com/files/pk_technique.pdf

 

[BLADEMDA]

that study has nothing to do with your arbitrary maximum aggregate ketamine dose.

Feel free to give as much Ketamine via an Infusion as you want. But, I will stick to the 200 mg total as I live in a high malpractice State. When something goes wrong (and it eventually does) your anesthetic will be heavily scrutinized.

In addition, the evidence of the superiority of high dose Ketamine vs. low dose just isn't there. Friedberg has shown that a total of 200 mg is safe, effective and has minimal to no side effects.

The only subgroup I would be willing to give more are the Opioid addicted patients (drug addicts). Those patients are in a whole different category.

 

[Idiopathic]

i cant really argue with those examples, since they dont apply to the discussion

 

[Arch Guillotti]

I can't believe that we are talking about a Friedberg study.

 

[BLADEMDA]

I can't believe that we are talking about a Friedberg study.

Like it or not he did some decent work on safety of Ketafol anesthesia for outpatient surgery. I pretty much stick to the 200 mg Ketamine rule and my post op complaints are minimal.

For Spine cases we are doing a mixed anesthetic anyway so I see little reason to blast patients with large doses of Ketamine. The data is very supportive of low dose ketamine infusions and that easily keeps the total under 200 mg.

 

[fakin' the funk]

Large doses of ketamine (>2 mg/kg) are associated with unacceptable psychotomimetic side effects (10). Common complaints include hallucinations, vivid dreams, cognitive decline, and emergence confusion (10). However, side effects are rare with a reduced dose of ketamine ranging from 0.15 to 0.5 mg/kg (10,25,26).

Those are clearly bolus doses, not cumulative doses applying to 6-hour back wacks.

 

[fakin' the funk]

i also like this as part of a balanced TIVA for MEP monitoring, which includes propofol, remi/su, lidocaine, ketamine infusions (sometimes will add precedex)

How much lido? I know the studies about ileus duration in abdominal surgery use fairly high dose, pretty much the Vtach dose (1-2 mg/kg load, then 1-2 mg/min).

What benefit does the precedex add in that cocktail?

 

[Idiopathic]

i like it in cases where MEP is monitored simply because it can decrease the amount of propofol we use

i run lidocaine at 2mg/min during the case, I may hold off on the bolus at induction, where i would normally give 1mg/kg. ive seen one episode of PR interval prolongation, and no conduction abnormality of significance. i would avoid it in patients with significant renal/hepatic dysfunction

 

[pgg]

IlDestriero mentioned methadone in his kids, but I like it in adults too.

I can't believe that we are talking about a Friedberg study.

But he invented ketafol! Don't we owe him royalties or something for infringing on his patented Minimally Invasive Anesthesia™?

 

[BLADEMDA]

Those are clearly bolus doses, not cumulative doses applying to 6-hour back wacks.

OKay. So how much Ketamine do you want to give an 85 year old (total) or a 43 year old outpatient (4 hour case)? Where is the evidence that HIGH DOSE Ketamine is superior to low dose Ketamine for Spine cases?

Since we are giving a "mixed anesthetic" why not go conservative with the Ketamine?

I do agree that the exact total dosage of Ketamine for each subroup has not been thoroughly investigated; but, for my needs a total maximum dose of 2mg/kg is sufficient.

 

[BLADEMDA]

i like it in cases where MEP is monitored simply because it can decrease the amount of propofol we use

i run lidocaine at 2mg/min during the case, I may hold off on the bolus at induction, where i would normally give 1mg/kg. ive seen one episode of PR interval prolongation, and no conduction abnormality of significance. i would avoid it in patients with significant renal/hepatic dysfunction

Try adding up to 1/2 MAC of ISO to your mix. Cheap and Effective with MINIMAL affect on the MEP.

 

[IlDestriero]

Try adding up to 1/2 MAC of ISO to your mix. Cheap and Effective with MINIMAL affect on the MEP.

That wouldn't fly where I work, or at the last place. The surgeons would have a fit if it wasn't a TIVA.

 

[proman]

That wouldn't fly where I work, or at the last place. The surgeons would have a fit if it wasn't a TIVA.

They are idiots.

All these concoctions are just overly complicated with more drips than I do a cardiac case with.

I did several dozen adult and peds scoliosis repairs in residency (hospital does +1,000 adult spines a year, and 4-8 idiopathic adolescent repairs a day):

1/2 MAC iso + 50% nitrous. Methadone if you want to be fancy.

Premeds to be really fancy: APAP 1000mg, tizanidine 4mg, gabapentin 900mg. Ketamine 0.1mg/kg before baseline signals.

 

[BLADEMDA]

They are idiots.

All these concoctions are just overly complicated with more drips than I do a cardiac case with.

I did several dozen adult and peds scoliosis repairs in residency (hospital does +1,000 adult spines a year, and 4-8 idiopathic adolescent repairs a day):

1/2 MAC iso + 50% nitrous. Methadone if you want to be fancy.

Premeds to be really fancy: APAP 1000mg, tizanidine 4mg, gabapentin 900mg. Ketamine 0.1mg/kg before baseline signals.

Nice. KISS. But, the lawyers around my area can do a Google search pretty well. FWIW, I read the entire study in February's A and A.

http://news.bioscholar.com/2011/01/nitrous-oxide-anesthesia-ups-heart-attack-risk.html

"The results showed a persistently higher rate of myocardial infarctions among patients who received nitrous oxide. The odds of myocardial infarction were nearly 60 percent higher than in patients not receiving nitrous oxide, after adjustment for other risk factors such as age, history of heart disease, and length of surgery."



For the past 5-6 years I omit the N20 (just say NNO) to all ASA 3 and 4 cases or all patients having a long anesthetic. I personally just use N2O for just a few minutes at the end of cases to assist in a rapid wake-up.

 

[IlDestriero]

They are idiots.

All these concoctions are just overly complicated with more drips than I do a cardiac case with.

I did several dozen adult and peds scoliosis repairs in residency (hospital does +1,000 adult spines a year, and 4-8 idiopathic adolescent repairs a day):

1/2 MAC iso + 50% nitrous. Methadone if you want to be fancy.

Premeds to be really fancy: APAP 1000mg, tizanidine 4mg, gabapentin 900mg. Ketamine 0.1mg/kg before baseline signals.

Perhaps, but it's their party and it's easy to do a TIVA. I don't really care why their protocol is what it is.
Pile on the primordial dwarves, non responsive pretzels, etc and you're lucky to have signals at all. An idiopathic spine is just a dream.

 

[proman]

I agree it's difficult but TIVA is not perfect either and the best person to approach this is the neurology attending. It's not difficult to run propofol, I do it all the time with MEPs because the surgeon who wants it is unreasonable. But adding methodone and ketamine and hydromorphone and Precedex and remi and who knows what else really makes for a sloppy anesthetic and I don't think it's necessary, especially when we have this great drug called "volatile anesthetic". Used appropriately, volatiles do not impair evoked potentials and the evidence supports that. That's what we should be advocating.

 

[Surfer]

.

 

[Idiopathic]

many roads lead to rome. i think that comparing these spines to the 12 year old scoliosis kids is not appropriate. im talking about basic 1-2 level C/T/L spines, +/- MEP, having ketamine running throughout and continuing it into PACU. They use less opioid in PACU and the first 24 hours, and may actually shorten time until fitness for discharge as a result. it has zero risk and my patients have done very well on it.

for the extremely complicated OA/AA fusions or 6 level jobs, I dont really worry about ketamine that much, although I have no problem including it. it something you dont have to titrate and that is beneficial when monitoring.

 

[Idiopathic]

I agree it's difficult but TIVA is not perfect either and the best person to approach this is the neurology attending. It's not difficult to run propofol, I do it all the time with MEPs because the surgeon who wants it is unreasonable. But adding methodone and ketamine and hydromorphone and Precedex and remi and who knows what else really makes for a sloppy anesthetic and I don't think it's necessary, especially when we have this great drug called "volatile anesthetic". Used appropriately, volatiles do not impair evoked potentials and the evidence supports that. That's what we should be advocating.

citation, please

 

[proman]

citation, please

Here are a couple. Better question, why don't you ask for the citations that show an unacceptable high number of false negatives SSEP or MEP with the use of volatile anesthetics? That's the real question.

PMID: 18713887
PMID: 19878711
PMID: 16780078
PMID: 16324298
PMID: 16628063

The point of all these, and more studies out there, is that yes, evoked potentials are affected by both intravenous and inhaled anesthetics. Both decrease signals in a dose-dependent manner, and inhaled anesthetics are more potent depressants, particularly above 1 MAC. However, using less than 0.8 MAC does not impair the ability to assess TcMEP. Stimulatory thresholds are higher. The key is to set the anesthetic depth prior to obtaining the baseline signals and not adjusting anesthetic depth. This discussion has to involve adolescent idiopathic scoliosis because that's where the high quality research has been done on evoked potentials and neurologic outcome.

 

[countingdays]

citation, please

Doesn't the effect of volatile depend on the stimulation technique? If neuromonitoring can get good signal using high intensity, trains of stimuli despite 0.5 MAC of volatile, then do it. The monitoring can adjust to the anesthestic technique instead of vice versa.

 

[Idiopathic]

Here are a couple. Better question, why don't you ask for the citations that show an unacceptable high number of false negatives SSEP or MEP with the use of volatile anesthetics? That's the real question.

PMID: 18713887
PMID: 19878711
PMID: 16780078
PMID: 16324298
PMID: 16628063

The point of all these, and more studies out there, is that yes, evoked potentials are affected by both intravenous and inhaled anesthetics. Both decrease signals in a dose-dependent manner, and inhaled anesthetics are more potent depressants, particularly above 1 MAC. However, using less than 0.8 MAC does not impair the ability to assess TcMEP. Stimulatory thresholds are higher. The key is to set the anesthetic depth prior to obtaining the baseline signals and not adjusting anesthetic depth. This discussion has to involve adolescent idiopathic scoliosis because that's where the high quality research has been done on evoked potentials and neurologic outcome.

the discussion here is regarding MEP, and none of those studies even mention MEP.

ultimately, the point is that you will have a neurosurgeon who wants monitoring and a neuromonitoring group that wants you to avoid volatile anesthesia because it introduces a level of inefficiency into their measurements. if you are going to have a long career as an anesthesiologist, you will have to learn to compromise. thats all. we dont use volatile in our MEP cases because there is evidence to suggest that it hampers the ability to generate good signals and because there is no good evidence that we should use it, especially when we have perfectly reasonable alternatives.

 

[proman]

the discussion here is regarding MEP, and none of those studies even mention MEP.

Wrong. Thanks for the advice on how to have a successful career, it's worth what I've paid for it.

Anyway, for the visual people:

 

[Idiopathic]

Doesn't the effect of volatile depend on the stimulation technique? If neuromonitoring can get good signal using high intensity, trains of stimuli despite 0.5 MAC of volatile, then do it. The monitoring can adjust to the anesthestic technique instead of vice versa.

so when your surgeon asks you specifically for a TIVA, what is your response? also, it seems as though if you have to use higher stimulation intensity, odds are you narrow your therapeutic observational range, and are more likely to miss one. even one miss may not be disastrous, but may necessitate an unnecessary emergent decompression, an intraop wake up, or an outright cancellation.

 

[Idiopathic]

hey look proman, i can see why you want to just use Anesthesia A for these patients, its easy, you dont have to do much, but lets just agree that its probably at best a substitute that makes the case more challenging for everyone but you

 

[Idiopathic]

DISCUSSION: In children, anesthesia maintenance with 2% sevoflurane prolongs median SEP latencies in a manner that is similar to those reported for other volatile anesthetics. However, SEP monitoring can be done with sevoflurane inhalation, but the dosage should be adjusted due to interindividual variability. Co-administration of ketoprofen, and fentanyl did not affect the SEP latencies, but post hoc analysis suggested that older children had a decrease in cortical amplitudes.

Abstract
Electrophysiological recordings of the auditory system are commonly performed in deeply anesthetized animals. This study evaluated the effects of various concentrations of the volatile anesthetic isoflurane (1-3%) on the compound action potential (CAP), cochlear microphonic (CM) and auditory brainstem response (ABR). Recordings were initiated in the awake, lightly restrained animal. Anesthesia was induced with a single dose of Hypnorm (fentanyl and fluanisone). After tracheostomy increasing isoflurane concentrations were applied in N(2)O/O(2) via controlled ventilation. Data were compared to recordings in the awake animal using repeated measures ANOVA and Dunnett's post hoc test. On average, isoflurane dose-dependently suppressed the amplitude and increased the latency of the CAP. CM amplitude was suppressed. These effects were most profound at high frequencies and were typically significant at isoflurane concentrations of 2.5% and 3%. Amplitude and latency of the second negative peak of the CAP (N(2)) were affected to a greater extent compared to the first peak (N(1)). On average, isoflurane dose-dependently reduced the amplitude and increased the latency of the ABR. These effects were typically significant at an isoflurane concentration of 2%. Effects on peak IV and V were more pronounced compared to the early peaks I and III.

CONCLUSIONS: VEP was most strongly affected with anesthetics, and ABR showed less marked influence of sevoflurane and propofol. Propofol based TIVA technique would induce less change in evoked potentials than sevoflurane.

CONCLUSION: The effects of three volatile anesthetics on SSEP and BIS are significant in dose-dependent manner. Anesthetic regimen of 0.75 MAC isoflurane for intraoperative cortical SSEP monitoring may be optimal. It seemed that the correlation between BIS and short-latency SSEP was poor, although both are associated with the effects of anesthetics on cerebral cortex.

Abstract
The aim of the present study was to compare the influence of volatile anesthetics on transcranial motor-evoked potentials (tcMEP) in humans anesthetized with propofol/fentanyl/nitrous oxide and on partial neuromuscular blockade (NMB). The authors studied 35 ASA I and II patients who were undergoing elective craniotomy and brain tumor resection. The patients were randomized to one of three groups to receive halothane (HAL), isoflurane (ISO), or sevoflurane (SEV). Anesthetic depth was initially adjusted using the bispectral index to 40+/-5, and NMB was adjusted to 40%-50% of one twitch of train of four (T1) after recovery from intubation. MEPs with train of five square-wave pulses were elicited using screw electrodes placed in the skull over C3-C4. After craniotomy, the inhalational agent was introduced at 0.5 MAC and then 1.0 MAC (20 minutes each), and the effects on MEPs, NMB, and hemodynamic variables were studied. A decrease in BIS and systolic blood pressure was observed with all agents. Both SEV and ISO at 1.0 MAC significantly decreased train-of-four ratio from 38.4+/-18.1 at control to 19.0+/-9.7 and from 35.3+/-12.4 to 26.1+/-13.7, respectively (P<0.001), but not HAL at 1.0 MAC. The amplitudes of tcMEPs were significantly reduced by all agents at 1.0 MAC, with the effect being less in HAL at 0.5 MAC. We have shown that HAL had a lesser suppressive effect on MEPs than either ISO or SEV at 0.5 MAC, which was partially due to a lesser degree of NMB.

the data cited above.

 

[proman]

Spine (Phila Pa 1976). 2010 Dec 15;35(26):E1627-9.
Successful monitoring of transcranial electrical motor evoked potentials with isoflurane and nitrous oxide in scoliosis surgeries.

CONCLUSION: Although isoflurane and nitrous oxide diminish tceMEP responses, reliable monitoring can still be accomplished while using significant levels of inhalational anesthetic agents.

J Neurosurg Anesthesiol. 2006 Jul;18(3):211-4.
Intraoperative motor-evoked potential monitoring in scoliosis surgery: comparison of desflurane/nitrous oxide with propofol total intravenous anesthetic regimens.

CONCLUSIONS: This is the first study comparing the use of desflurane and TIVA showing that both anesthetic regimens allowed successful intraoperative monitoring useage throughout the procedures. For MEP recording, the AH was the preferred muscle with a desflurane anesthetic regimen.

We could do this all day. Motor evoked potentials are not a contraindication for volatile anesthetics. Now show me the study that inhaled anesthetics produces more false negatives than IV anesthetics and I'll probably change my practice. BTW a simple anesthetic is my goal and there's nothing wrong with that.

 

[Idiopathic]

oh are you using desflurane with your spines? probably shouldnt add N20 to volatile for these patients...

nobody said they were a contraindication. i envy you being able to bring 35 year old data into an OR and challenge the neurotechs and neurosurgeons, i may agree with you at heart, but you are talking about a change in practice and that requires a little more data than has been presented. your top 5 articles hardly mentioned MEP and NONE suggested that volatile anesthesia was preferrable.

from neuromon.com

7) With myogenic MEP recordings, amplitude is no longer the issue; MEP amplitudes are much greater than those of SSEP, in the millivolt range as compared to the microvolt range. With MEP, the issue is response threshold, and presence or absence of the response. High anesthetic concentrations tend to increase the required stimulus level or completely abolish the response.

 

[proman]

citation, please

Copius evidence cited, over a 35 year period. Now show me the higher rate of false negatives which is the foundation of your argument for TIVA.

 

[Idiopathic]

youve done nothing to convince me that a change in practice is necessary. we do things a certain way, in conjunction with the other operative teams, because that is the BEST way to monitor MEP, and that point is not up for debate. you may have an alternative way, but certainly not a better way, and asking for me to prove that your way isnt better isnt realistic. you are trying to convince someone to change their practice, and youve provided no compelling evidence to do so, in fact, all the evidence says is that its simply acceptable, not optimal. for me, thats not enough.

carry on all, thread hijack over

 

[bullard]

How about lidocaine vs ketamine drip for long back whacks or big belly cases? Anybody have an argument in favor of one or the other?

 

[epidural man]

I am going to use this regimen (below) tomorrow. I wanted all of your input on the dose of ketamine ...

I use the doses that De Kock used in his study...

Balanced analgesia'in the perioperative period: is there a place for ketamine?
[M De Kock, P Lavand'homme… - Pain, 2001 - Elsevier


He bolused 0.5mg/kg, then infused .25mg/kg/hr (one of the arms).

I think it works great.

By the way, that study above is really a wonderful study. They show decreased wound hyperalgesia 6 MONTHS after surgery in one of the ketamine arms - and they compare it to ketamine epidural. It is a well done study.

Surprisingly, none of the reviews or new papers on ketamine ever reference this article.

I agree that you should never exceed 200mg.

 

[epidural man]

How about lidocaine vs ketamine drip for long back whacks or big belly cases? Anybody have an argument in favor of one or the other?

do them both....(tons of good research that lidocaine infusions decrease opioid usage and increase time to bowel recovery - in fact recent study compared TEA to iv lido - no difference in return to bowel function....no advantage to lido on same day patients though)

I just did that last week on a guy that was taking 20 percocet/day. He woke up great and happy and not in pain, and I gave him less IV morphine equivalents during the case than he usually had each day.

My next thing I want to start doing is IV methadone - 1 dose - for the case. Anyone see the recent article on this? Pretty cool stuff....

 

[jwk]

Doesn't the effect of volatile depend on the stimulation technique? If neuromonitoring can get good signal using high intensity, trains of stimuli despite 0.5 MAC of volatile, then do it. The monitoring can adjust to the anesthestic technique instead of vice versa.

the discussion here is regarding MEP, and none of those studies even mention MEP.

ultimately, the point is that you will have a neurosurgeon who wants monitoring and a neuromonitoring group that wants you to avoid volatile anesthesia because it introduces a level of inefficiency into their measurements. if you are going to have a long career as an anesthesiologist, you will have to learn to compromise. thats all. we dont use volatile in our MEP cases because there is evidence to suggest that it hampers the ability to generate good signals and because there is no good evidence that we should use it, especially when we have perfectly reasonable alternatives.

We do a ton of spine cases for at least 20 different spine surgeons (some of whom don't use ANY neuro monitoring at all) , and with a very large anesthesia department, do them a lot of different ways.

Best practice - communicate with your surgeon and neuro-monitoring techs. Find out what they think they want vs what you can actually provide. Most of ours tend to be 1/2 MAC, no roc after induction, no N2O, propofol infusion, and plenty of narcs, +/- ketamine. Most use the BIS, few get invasive monitoring. It works well for most of the different spines and modes of neuro monitoring that we use. As good as we want them to think we are, we're not magicians, and the more they want to limit our technique/agents/drugs, the higher the chance something will occur during the case that they don't like.

 

[sevoflurane]

Not sure if I like the bis for long whacks in the prone position. It's like having shards of glass on your forehead + the weight of your head on that glass for 4-5 or more hours + facial edema.

I don't use it much anymore anyways (the exception is a cardiac case). It seems to be an unecessary expense.

Just my opinion.

 

[sevoflurane]

Ketamine is one of my favorite drugs. Long half-life with excellent analgesia. We had some spines that went 8 hours during residency (slow surgeon + big whack). I would sometimes go over 200mg.... the half life is like 2.5-3 hours, so I was cool with that. They didn't wake up in the middle of a bad trip. Precedex seemed to help that delirium. Most the spine patients have been on narcs for a while so it's a great choice for that population.

In PP, we never take that long so I don't think it is necessary to go over 200mg unless you have a biggens on your hand.

 

[Frank Rizzo]

We do a ton of spine cases for at least 20 different spine surgeons (some of whom don't use ANY neuro monitoring at all) , and with a very large anesthesia department, do them a lot of different ways.

Best practice - communicate with your surgeon and neuro-monitoring techs. Find out what they think they want vs what you can actually provide. Most of ours tend to be 1/2 MAC, no roc after induction, no N2O, propofol infusion, and plenty of narcs, +/- ketamine. Most use the BIS, few get invasive monitoring.

👍 just summed up my standard approach. Nothing fancy or cute. Guess what???? They do just fine.