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Kevin,
 
I can see your point, and understand your position.  At a former hospital, we non-anesthesiologists (including PICU and ER docs) were barred from using ketamine for *any* sedation because it was a "dissociative anesthetic", and only anesthesiologists were allowed to administer anesthetics.  We could give as much midazolam and fentanyl as we wanted.  Made no sense to me, as ketamine was less likely to cause profound hypotension or respiratory depression.  Luckily, the chair of anesthesia at the time was let go, and the interim chair allowed us to use ketamine, provided we could demonstrate that we had the knowledge and skills necessary to use it safely.  We did, and when the anesthesia department hired a replacement, he reviewed our sedation protocols and had no concerns about our use of ketamine.
 
I agree with you - ketamine is different than the other agents we use.  It can produce deep sedation (and even anesthesia) while simultaneously permitting adequate spontaneous ventilation, oxygenation, and preserves (and even augments) cardiovascular tone.  It doesn't produce the same cardiorespiratory depression that other agents do, even as patients drift along the ill-defined sedation-anesthesia continuum.
 
However, when you *do* run into problems with ketamine, the advanced airway skills needed to support the patient are the same skills needed to support patients who lose their airways with other agents.  And, in the event of a ketamine shortage, you may have to use other agents anyway, so why not get credentialled to provide procedural sedation, irrespective of the agent used?
 
We have two pediatric hospitalists at our institution, and are looking at expanding the program to at least a third hospitalist, and are developing a procedural sedation model using pediatric hospitalists as sedation providers, so I can definitely "feel your pain".  If your peds hospitalists are PALS (or APLS or similar) certified, they already have demonstrated the skills needed to maintain/secure the airway in most pediatric patients, so hopefully you won't have much difficulty getting the needed certification.
 
Consider getting your hospitalists credentialled to provide "procedural sedation", including (but not limited to) ketamine.  It might be a bit more work, but your anesthesia department will be more likely to support you.
 
Michael Verive



--- On Wed, 11/23/11, Kevin Powell <[log in to unmask]> wrote:

> From: Kevin Powell <[log in to unmask]>
> Subject: Re: Ketamine Sedation Classification: Moderate vs Deep vs Dissociative?
> To: [log in to unmask]
> Date: Wednesday, November 23, 2011, 6:03 AM
> I also think we would agree on the
> vast majority of ideas around sedation,
> but the couple disagreements are crucial to a pediatric
> hospitalist.
> 
> I agree that the levels of sedation are not distinct
> levels.
> 
> I certainly agree that patients can easily get more sedated
> than intended. I
> would agree that dosing of meds is not linear, as in 2x
> more med is twice as
> sedated. My use of the jargon "linear" reflects my
> engineering/math
> background. I tried to clarify that jargon with "simple,
> single, linear."
> Perhaps the term "one-dimensional" would be clearer.
> 
> Your claim that sedation is a continuum, and your repeated
> use of the term
> light and deep, reinforces that one-dimensional idea. It
> implies that there
> are only two directions that sedation can go, lighter or
> deeper, and that
> the sedation can be rated on a single scale from 1 (none)
> to 0 (general
> anesthesia). The current model (let's use the ASA 2002
> guidelines that
> changed the definitions, Anesthesiology 2002; 96:1004–17)
> created a scale
> which has milestones based on patient response to stimuli.
> But  there were 3
> other scales in that model - based on maintenance of
> airway, spontaneous
> ventilation, and CV function.
> 
> A one-dimensional approach implies that when depressed
> responsiveness is at
> a moderate level, then the other 3 variables are at similar
> points in their
> scales of 1 to 0. This is an oversimplification and
> ketamine is the best
> example of this. Ketamine achieves a much greater drop in
> responsiveness for
> the same risk of losing spontaneous ventilation, when
> compared to
> midaz/fentanyl. With repeated boluses ketamine can maintain
> the same deep
> level of change in responsiveness as pentobarbital does,
> but with a much
> lower risk of hypotension. Rather than a one-dimensional
> continuum, sedation
> with different agents is at least two dimensional, if not
> >4. (To the 4
> scales in the ASA guidelines I would add "probability of a
> bad outcome
> unless patient receives a skilled intervention." )
> 
> Unfortunately, the one-dimensional model leads to equating
> procedural
> sedation with ketamine to deep sedation with propofol,
> based on change in
> responsiveness. Here again is where we disagree. In many
> hospitals where the
> chair of anesthesia makes the rules, that
> oversimplification of classifying
> ketamine as equal to propofol interferes with the
> credentialing of
> procedural sedation by pediatric hospitalists, who almost
> always want the
> child unresponsive to mild stimulation. The term
> "dissociative anesthetic"
> is a terminology to remediate this errant one-dimensional
> model.
> 
> I agree with your claim that there currently is not a carve
> out for
> dissociative sedation. The term dissociative is only used
> once in the 2002
> guidelines, and is followed by a hedge returning to the one
> dimensional idea
> of a "level."  That was an error in the 2002
> guidelines. That misconception
> has yet to be fixed. The articles cited in the original
> post of this thread
> continue to add to the literature trying to fix the
> problem. As I stated in
> my post, this issue is not perceived as a major stumbling
> block for some
> subspecialties such as intensivists. That perception may
> explain why the
> Society for Pediatric Sedation has not adequately addressed
> the issue after
> 9 years.
> 
> Kevin
> 
> 
> 
> -----Original Message-----
> From: Michael Verive [mailto:[log in to unmask]]
> Sent: Tuesday, November 22, 2011 8:13 PM
> To: [log in to unmask];
> Kevin Powell
> Subject: Re: Ketamine Sedation Classification: Moderate vs
> Deep vs
> Dissociative?
> 
> 
> Kevin,
> 
> I think we agree more than disagree on this.  I also
> agree that ketamine is
> relatively safe (and safer than fentanyl/midazolam when
> used to provide the
> same level of sedation).
> 
> Sedation *is* a continuum, and I never suggested that it
> was linear, nor did
> I suggest that the "levels" of sedation were distinct
> levels.  Sedation is
> not predictable, and patients can easily become more or
> less deeply sedated
> than intended.  There is significant variation in
> patient response to
> ketamine (and other sedative/anesthetic agents), so even if
> you intend to
> produce a "light" dissociative state, you may find that
> patients often
> become more deeply sedated than intended, especially if you
> need to use
> multiple doses of ketamine.
> 
> Regardless of the level of sedation intended (or what you
> want to call it),
> the sedation provider needs to be able to rescue patients
> who become more
> deeply sedated than intended.  Credentialling for
> ketamine (which is
> typically used to produce a level of sedation in children
> that borders on
> general anesthesia) will probably need to be on the same
> level as propofol,
> which is also very safe when used by personnel skilled in
> titrating it and
> rescuing patients who become too deeply sedated.
> 
> Michael J. Verive, MD, FAAP
> Medical Director - Pediatric Intensive Care
> St. Mary's Hospital for Women and Children
> 3700 Washington Ave
> Evansville, IN 47750
> 
> 
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> 

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