Page 106 - Journal of Special Operations Medicine - Fall 2015

An Ongoing Series

Journal Club: Ketamine in the Emergency Department

Joshua Banting; Tony Meriano, MD

CONCEPTS AND OBJECTIVES

In this column of Clinical Corner, we are going to switch Selected Excerpt: TCCC Guidelines 140602 3
things up a little. We are going to review a journal article
that is applicable to the Special Operations Forces (SOF) Analgesia on the battlefield should generally be achieved
Medic. We plan on continuing to present clinically rel- using one of three options:
evant cases, but every so often an article is published Option 3
that we simply must take a deeper look at. Moderate to Severe Pain
Casualty IS in hemorrhagic shock or respiratory distress
Keywords: ketamine; pain, acute OR
Casualty IS at significant risk of developing either
condition
– Ketamine 50mg IM or IN
The Article Or
– Ketamine 20mg slow IV or IO
Ahern TL, et al. The First 500: initial experience with * Repeat doses q30min prn for IM or IN
widespread use of low-dose ketamine for acute pain man- * Repeat doses q20min prn for IV or IO
agement in the ED. Am J Emerg Med. 2015;33:197–201. * End points: Control of pain or development of
nystagmus (rhythmic back-and-forth movement of
Why This Is Important to the SOF Clinician the eyes)
In the latest Tactical Combat Casualty Care (TCCC)
guidelines, ketamine plays a role in the care of combat Analgesia notes:
a. Casualties may need to be disarmed after being given
casualties. The problem is that many SOF Medics have OTFC or ketamine.
not had a lot of clinical experience with this medication. b. Document a mental status exam using the AVPU
This is due in part to the fact that ketamine has not tra- method prior to administering opioids or ketamine.
ditionally been used as a primary analgesic medication. c. For all casualties given opioids or ketamine
Instead, it has largely been used as an option for proce- – monitor airway, breathing, and circulation closely
dural sedation. An important clinical feature of ketamine
is the fact that the drug has a degree of different dose-de- frequency of side effects are not widely known. A Tacti-
pendent effects. Administered in a dose above 1 to 2mg/ cal Medic may have some apprehension using this medi-
kg intravenously (IV) or 4mg/kg intramuscularly (IM), cation if he has not had much experience with this drug.
the drug is a potent dissociative drug. A dose at this level This is why this article is so important; it shows the real-
is considered a dissociative anesthetic dose. Patients who time use of this medication in subdissociative (analgesic)
receive this dose maintain their respirations but typically doses. The limitation of this study is that it is used in a
are nonverbal and unable to follow commands; they are civilian hospital–based setting. Therefore, the patients
often cataplexic with a vacant dissociated stare. Doses were typically older and had more comorbidities than
under this level are known as subdissociative doses and might be seen in the tactical setting. If anything, one
have been used for a variety of conditions, including an- might infer that there might be fewer issues with a mili-
algesia. This subdissociative dose (also called subanes- tary age population.
1,2
thetic dose or low-dose ketamine [LDK]) is typically 0.1
to 0.3mg/kg. In the latest TCCC guidelines, ketamine The use of ketamine as an analgesic has many advan-
3
is an option for analgesia or an adjunct for analgesia in tages compared with traditional analgesics. Ketamine
combination with opioids. has been in worldwide use since its development in
the 1960s. It works as an antagonist to N-N-methyl-
The literature supporting the use of ketamine in these d- aspartate (NDMA) receptors. It interferes with the
subdissociative doses is limited. Further, the type and transmission of information from the peripheral nervous

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