Ketamine... PCA?

[Eydawn]

Hi folks. At my paid gig on a hospital floor, recently, due to shortages of our more popular PCA drugs and patients with weird narc sensitivities/allergies, we've started having some post-surgical orthopedic patients come up on ketamine PCAs. Most of these patients have been elective back or knee surgeries (haven't had any hips yet on it).

In my anecdotal, population size <12 study, I'm beginning to think this is a really, really shitty idea.

What do y'all think of ketamine as a PCA? Specifically looking to our higher level folks here that understand all the pharm ramifications... thoughts?

I think it doesn't seem to provide the level of analgesia that we expect from a PCA. I also think that it makes many of my patients nuttier than squirrel poo. I'm talking hallucinations, self injurious behavior (leaping out of bed, pulling catheters/IV's/dressings), crazypants to the point of needing benzo sedation and/or 1:1 observation (expensive, harder to staff, takes away from having staff on the floor). Dissociative anaesthesia, in "push your little button" form seems to just not be working out that well.

What say you on risk/benefit between ketamine PCA and something like a local block (on-q balls) that can be dialed back slowly?

Wendy

CO EMT-B

RN-ADN Student

[HarryM]

I know that in most hospitals here Ketamine would not be administered as a PCA. And even when administered as an analgesic it's usually given with a small amount of a benzodiazepine which significantly reduces the halluncinations etc effects. Other than that, ketamine only really gives that sort of negative patient reaction in smaller doses. Thus recently in our service our ketamine dosage guideline has been upped as higher doses reduce the hallucinations apparently (it's not im my personal scope of practice, but I read the memo).

[Vorenus]

First to say that I`m not familiar with PCA systems at all, since never having worked in a clinical setting aside from my apprenticeships.

Ketamine wouldn`t strike me as the drug of choice for a PCA, though, considering its rather heavvy psychotropic and hallucinatory side-effects. Former named characteristics are the reason why ketamine should be administered in a combination with benzos - I can`t really see how this could effectively be acchieved with a PCA, considering the corresponding imbalance between ketamine and the benzos.

As said, just my personal thoughts without being familiar with the PCA administration of ketamine.

I know that in most hospitals here Ketamine would not be administered as a PCA. And even when administered as an analgesic it's usually given with a small amount of a benzodiazepine which significantly reduces the halluncinations etc effects. Other than that, ketamine only really gives that sort of negative patient reaction in smaller doses. Thus recently in our service our ketamine dosage guideline has been upped as higher doses reduce the hallucinations apparently (it's not im my personal scope of practice, but I read the memo).

As an analgesic?

This would imply that you haven`t had enough in your guidelines before, or that you´re analgesic dosages tend to be more sedative now...

[WestMetroMedic]

Do you get the reemergence effect with the lower doses of Ketamine typically associated with pain control?

We recently added a Ketamine option as an adjunct to analgesia at a dose of 0.5mg/kg. Our medical director cautioned against it citing cost and the associated hospital course, but they never mentioned anything about administering a benzo with it like they do with our behavioral health doses of 2 mg/kg IV or 5mg/kg IM.

[Bernhard]

Benzos are not required for Ketamine, but they are a friendly gesture...

In lower (analgesic) doses the psychotropic effects are near zero, if getting sedative/anaesthetic the probability gets higher. It's kind of a play with unknown probabilities on the given patient.

In a side effect this enables you to give Ketamine in higher doses without respiration depressive Benzos, if the actual situation calls for that trick. A large part of your patients will get over it without the psychotropic side effects. But noone really can say how many (I don't have research papers at hand, maybe someone actually can quantify it).

So Ketamine is a great tool. As with every tool you need to know, where and how to use it (risk/benefit).

But if you allow patients do dose themselves with Ketamine by PCA this simply would raise the probability of having effects as Wendy described. I would consider this an inadequate substitution of better drugs especially if it's due to a bad risk/benefit analysis. But what else, if no better drug is available?

However, we're talking about the U.S. here, land of the most sophisticated medical system, if I recall correctly...come on, "drug shortage", really, please?!?

[rock_shoes]

Benzos are not required for Ketamine, but they are a friendly gesture...

That's probably about the best way I've heard someone put the ketamine/benzo relationship.

Sent from my SGH-T989D using Tapatalk 2

[Doczilla]

However, we're talking about the U.S. here, land of the most sophisticated medical system, if I recall correctly...come on, "drug shortage", really, please?!?

Preach it, brother. Unbelievable how in one of the greatest nations on earth with outstanding health care, we can find ourselves wanting for morphine, which has been around for TWO CENTURIES and costs damn near nothing. All because of regulatory crap.

Regarding ketamine as a PCA drug, Bernhard has it right. There are also pain specialists doing ketamine infusions (yes, it's legit) for complex chronic pain syndromes such as reflex sympathetic dystrophy. These infusions are at higher doses than the PCA I think, since you are trying to get the patient into a bit of a twilight and keep them there for about 4 hours. These are often done on an outpatient basis, and have some fairly good outcomes.

'zilla

Edited August 18, 2012 by Doczilla

[croaker260]

Hi folks. At my paid gig on a hospital floor, recently, due to shortages of our more popular PCA drugs and patients with weird narc sensitivities/allergies, we've started having some post-surgical orthopedic patients come up on ketamine PCAs. Most of these patients have been elective back or knee surgeries (haven't had any hips yet on it).

In my anecdotal, population size <12 study, I'm beginning to think this is a really, really shitty idea.

What do y'all think of ketamine as a PCA? Specifically looking to our higher level folks here that understand all the pharm ramifications... thoughts?

I think it doesn't seem to provide the level of analgesia that we expect from a PCA. I also think that it makes many of my patients nuttier than squirrel poo. I'm talking hallucinations, self injurious behavior (leaping out of bed, pulling catheters/IV's/dressings), crazypants to the point of needing benzo sedation and/or 1:1 observation (expensive, harder to staff, takes away from having staff on the floor). Dissociative anaesthesia, in "push your little button" form seems to just not be working out that well.

What say you on risk/benefit between ketamine PCA and something like a local block (on-q balls) that can be dialed back slowly?

Wendy

CO EMT-B

RN-ADN Student

I would have some concern about managing emergence phenomena post ketamine in a post surgical patient "on the floor". Specifically, these can be restraint nightmares (pun intended) and add the recent surgery on top of it? hmmmmmmm.

theren there is the conscious sedation issue. In any other (in hospital) setting, ketamine, propofol, etc would have the airway cart standing by, and either the ER doc at bedside or even anesthesia a short call away

I am finding it hard to believe there arnt SOME opioids out there..even methadone is an option, though not a great one. And while PCA's are nice for more predictable drugs....Ketamine is not what I would classify as predictable. Perhaos another method..less problomatic. Perhaps transdermal fentanyl with PO opioids for breakthrough pain?

Granted I have no personal experience with this particular situation, but extrapolating from other settings, it seems like an accident waiting to happen.

[HarryM]

First to say that I`m not familiar with PCA systems at all, since never having worked in a clinical setting aside from my apprenticeships.

Ketamine wouldn`t strike me as the drug of choice for a PCA, though, considering its rather heavvy psychotropic and hallucinatory side-effects. Former named characteristics are the reason why ketamine should be administered in a combination with benzos - I can`t really see how this could effectively be acchieved with a PCA, considering the corresponding imbalance between ketamine and the benzos.

As said, just my personal thoughts without being familiar with the PCA administration of ketamine.

As an analgesic?

This would imply that you haven`t had enough in your guidelines before, or that you´re analgesic dosages tend to be more sedative now...

Yes we were underdosing for analgesia which had the effect of being effective as analgesia as it could be, while also bringing out hallucinatory effects at lower doses. The doses aren't more sedative after the increase, although we also do use ketamine as a takedown drug for chemical sedation/restraint.

Yes we were underdosing for analgesia which had the effect of being not as effective as it could be, while also bringing out hallucinatory effects at lower doses. The doses aren't more sedative after the increase, although we also do use ketamine as a takedown drug for chemical sedation/restraint.

[Vorenus]

Yes we were underdosing for analgesia which had the effect of being effective as analgesia as it could be, while also bringing out hallucinatory effects at lower doses. The doses aren't more sedative after the increase, although we also do use ketamine as a takedown drug for chemical sedation/restraint.

Never used it in that way (Propofol or Midaz) - wouldn`t an already agitated patient be more open for the psychotropic aspects of the drug, I wonder?

Any experience or studies in comparison to other sedatives?