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ties back to industry, with just 7 original articles spawning 8 is effective for pain management and reduced opioid consump-
reviews, highlighting a paucity of primary data relevant to this tion. 68–72 Ketamine also has a broad safety profile, making it
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medication. 42 difficult to overdose, though rapid administration and coad-
ministration with benzodiazepines may lead to laryngospasm
In September 2019, the CoTCCC considered the addition of and transient apnea and providers administering ketamine in
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sufentanil to the TCCC analgesia guidelines for patients with high doses should prepare to secure the airway if necessary.
moderate to severe pain without shock, respiratory distress, Of note, the mechanism of this apnea and laryngospasm is
or significant risk of developing either condition while in the unclear and may relate more to vagal stimulation than the pri-
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Tactical Field Care or Tactical Evacuation settings. Although mary effect of ketamine itself. 75
administering sufentanil does not require IV access, the deliv-
ery method of sufentanil is complicated secondary to the size Ketamine has been more frequently utilized since the devel-
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of the tablets and the delivery system; the small tablets could opment of the TCCC Triple-Option Analgesia Plan in 2014.
easy fall out of the dispenser and get lost. Another challenge Schauer et al. report that from 2007 to 2016, the proportion
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is that it is not rapidly cleared, increasing the risk of adverse of casualties receiving ketamine rose from 3.9% to 19.8%.
reactions when compared to OTFC. Similar challenges were Petz et al. in 2015 found that ketamine was the most com-
published in 2020 where hospital-based nurses and physicians monly delivered prehospital analgesic, given to 52% of casu-
rated the applicator as “somewhat easy” or “easy to dose” alties requiring pain control. 1
97% of the time, however with reclined patients, this percent-
age dropped to 87%, and in limited lighting situations this Subdissociative (Low Dose) Ketamine Dosing
percentage dropped further to 77%. 41 Low Dose Ketamine (LDK) has been reported between 0.1mg/
kg/dose to 0.4mg/kg dose. This dose is intended to provide
While the Army has added sufentanil to their medical supply analgesia without producing dissociation. 20mg IV or 50mg
system, it is not being added to the medic/prehospital kits as of IM/IN is the 2014 Triple-Option Analgesia Plan recommended
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the time of this writing. There is some evidence that sufentanil dose. A recent small case series of ketamine use in SOF training
is an effective analgesic, but there are few studies describing its mishaps (n = 34), found LDK was effective, but often needed
use as an analgesic in emergency department settings and there additional doses. Because of the safety of these straight doses
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were no studies found that evaluated sufentanil in a head-to- as well as the undesirability of having to perform math on the
head comparison with OTFC or ketamine. The CoTCCC battlefield, neither the 2014 guidelines nor the current TCCC
recommends obtaining additional experience and addressing guideline updates recommend weight-based dosing under du-
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this research gap before it can be considered for prehospital ress or stressed situations. Given that the weight of many ser-
use. Cost should also be taken into consideration. The current vice members exceeds 70 kg, it is important to recognize that
cost of sufentanil is $44.32/dose while 1600mcg of OTFC is 20mg IV ketamine may be an inadequate initial dose, hence the
$15.65/dose. 43 recommendation to administer a range of 20–30mg. To reduce
the steps required for adequate pain control in the prehospi-
QUESTION 2: What is the best initial dose of ketamine? tal environment, ketamine dosing in this change is based on a
Level of Evidence: B 100-kg patient. The wide safety margin of ketamine at lower
doses allows for standardized dosing. Keeping a weight-based
Ketamine synthesis first occurred in 1965 during an effort to
find an ideal IV anesthetic. It is a derivative of phencycli- option for dosing allows personnel in more static environments
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dine (PCP) and has analgesic properties along with being a to exercise their preference for finer tuned dosing and preserve
potent anesthetic and amnestic agent. The term dissociative resources. This recommendation reflects the concern that the
anesthetic referenced the unique state patients experience fol- current dose is not adequate while also staying within the safe
lowing ketamine administration. Ketamine is an N- methyl- nondissociative dosing range of 0.1–0.4mg/kg for a majority
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D-aspartate (NMDA) calcium channel antagonist. It is on of Service members. While this is an effective strategy, some
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the World Health Organization’s Essential Drug List. 47 medical personnel may prefer weight-based dosing.
The efficacy of LDK has been established in emergency de-
Unlike opioids, which have a tendency to lower blood pres- 78
sure, heart rate, and respiratory rate, ketamine can maintain partment settings. Miller and colleagues performed a study
hemodynamic stability and can increase blood pressure and on adult patients with acute abdominal, flank, low back, or
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heart rate. In a resource limited environment in patients with extremity pain. Forty-five patients either received LDK at
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an injury severity score of greater than eight, an association 0.3mg/kg or 0.1mg/kg of morphine intravenously. Ketamine
existed between ketamine receipt and improved systolic blood provided maximum pain relief (change in Numeric Rating
pressure versus opioid analgesia (P = .03). A previous con- Scale [NRS] of 4.9) within 5 minutes while morphine maxi-
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cern with concomitant use of ketamine with eye injuries and mum pain relief (change in NRS 5.0) occurred at 100 minutes.
TBI was based on overturned analyses and case reports; all While LDK yielded equal pain reduction scores compared to
subsequent research suggest that ketamine is safe for use in morphine, LDK provided maximum analgesia significantly
these casualties. 9,51–59 faster within 5 minutes and provided a moderate reduction in
pain for two hours. A randomized controlled trial (RCT) by
Motov et al. yielded similar results, concluding that LDK was
Ketamine’s properties make this medication more appropri-
ate than opioids for use in many tactical combat injury sit- a safe and effective method of providing short term pain relief
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uations. 60–63 It appears to be neuroprotective, 64,65 which may when compared to morphine. Several other studies, includ-
explain its role in decreased incidence of PTSD. The neu- ing a systematic review and meta-analysis support these two
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roprotective aspects relate to its antiinflammatory proper- papers showing that LDK is as effective as morphine with mild
ties. 65–67 Ketamine use in the hospital and perioperative setting adverse events and should be used routinely for pain greater
than 5 on the NRS scale. 80–83
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