Page 86 - JSOM Fall 2020

TABLE 5 Initial Ketamine Route and Dose (mg) for Training Casualties
Number of % of
Route Casualties Casualties Mean (SD) 95% CI* Range (mg) Minimum Dose (mg) Maximum Dose (mg) IQR
IM 10 29.4 37.00 (18.135) 25.76–48.24 55 20 75 25
IN 8 23.5 58.13 (27.247) 39.25–77.01 95 25 120 10
IO 0 0 — — — — — —
IV 16 47.1 48.44 (28.967) 34.25–62.63 85 15 100 33
*Due to sample sizes <30, variations may be noted with 95% CI calculations and SD should be considered

TABLE 6 Pain Scores Pre- and Post-Ketamine Administration As demonstrated in Schauer’s 2015 Battlefield Analgesia:
(N = 30*) TCCC Guidelines Are Not Being Followed. These changes
Median Minimum Maximum were not fully implemented for in theater training until March
(IQR) Range Pain Pain of 2014, demonstrating a 5-month lag from the announce-
Pre-ketamine 8.0 (3) 5 5 10 ment. During the time period of this study, from July 2013 to
3
Post-ketamine 0.0 (3) 8 0 8 March 2014, less than half of all patients received analgesia at
*Four casualties excluded related to incomplete pain documentation. the point of injury, with the highest rates of adherence occur-
ring within the SOF community. The delay in adoption, and
in the tactical setting is important for patient comfort, tactical lower rates of use of ketamine and pain treatment may have
efficiency, and consensus that pain associated with traumatic been attributed in part to a paucity of civilian clinical training
events can potentiate posttraumatic stress disorder (PTSD) opportunities, minimal use of ketamine during training events,
and chronic pain syndromes. Previous studies have found and the lack of experience of supervising physicians with ket-
1
that by treating pain, it can help prevent the development of amine. While the trend for better adherence would improve
PTSD. This study demonstrated pain scores were greatly re- over time, the overall compliance with the TCCC analgesic
5–7
duced after the administration of ketamine. The dissociative guidelines remains suboptimal. 2,4
effects of ketamine may also play a role in long term benefit to
the psychological health of the combat casualty, and therefore There are surgeons and emergency medicine physicians who
amnesia may not be a deleterious effect. 5 are not comfortable receiving a minimally responsive or unre-
sponsive trauma patient who has been given ketamine in the
Ketamine is thought to act as an NMDA receptor antago- prehospital setting (personal communication). When given in
nist at the GABA receptor complex causing anesthesia. It is larger doses, ketamine can cause significant sedation and on
8
further postulated that ketamine excites delta and mu opioid initial presentation to a trauma center, an obtunded trauma
receptors within the basal ganglia and thalamus producing patient may cause the attending physician concern regard-
analgesia, as well as stimulating catecholamine receptors and ing the possible presence of TBI despite no physical findings.
decreasing production of nitric oxide leading to a decrease of This concern may result in additional testing and possibly
hemodynamic instability frequently seen with opiates. Thus, unnecessary procedures such as endotracheal intubation. A
9
ketamine has prevalent mechanistic uses for sedation, analge- well-documented GCS by the medic prior to the administra-
sia, and anxiolysis. tion of ketamine would help assuage this concern. Ideally, a
prehospital system should gain the buy in from their receiv-
Ketamine was formally endorsed by the Defense Health Board ing hospitals prior to using ketamine in the field. This method
in 2012 along with endorsement from the TCCC. In recent could increase awareness with the use of ketamine and ad-
1
years, low dose ketamine has been utilized in far forward en- dress points of concern in different practice patterns. It may
vironments and is currently the first line pain medication for be worth noting that the documentation of the mental status
patients in shock or at risk of bleeding according to TCCC and Glasgow Coma Score prior to ketamine administration
guidelines. Discordant with the TCCC and DHB approving may reduce the concern for altered mental status related to
10
the use of ketamine as a front analgesic, only 39% of patients ketamine in trauma patients.
in Afghanistan from October 2012 to March 2013 received
pain control at the point of injury despite receiving good pain US military medical officers should have a pain management
control at Role 1 health care facilities in deployed locations. 11 protocol for their organization and this protocol should be in

TABLE 7 Other Drugs Administered With Ketamine (mg*)
Number of % of Range Minimum Maximum
Drug Route Casualties Casualties (mg) Dose (mg) Dose (mg) Mean (SD) 95% CI**
Midazolam IM 3 8.82 1 4 5 4.667 (0.577) 4.01–5.32
Midazolam IN 3 8.82 0.70 1.80 2.50 2.10 (0.361) 1.69–2.51
Midazolam IV 9 26.47 2 1 3 2.11 (0.546) 1.75–2.47
Hydromorphone IV 3 8.82 — 2 2 2.00 (0.000) —
Ondansetron IM 1 2.94 — 4 4 0.00 (0.000) —
Ondansetron Unknown 2 5.88 4 4 8 6.00 (2.828) 2.08–9.92
OTFC (µg) PO 8 23.53 800 800 1600 900 (282.843) 704.00–1095.99
*Oral transmucosal fentanyl citrate (OTFC) doses are in µg, not mg.
**Due to sample sizes <30, variations may be noted with 95% CI calculations and SD should be considered.

84 | JSOM Volume 20, Edition 3 / Fall 2020