Page 23 - Journal of Special Operations Medicine - Winter 2014

it difficult to move a casualty through heavy brush and
Appendix A Ketamine Questionnaire
the incoherent speech, was above the normal volume of
1. On a scale of 1 to 10, rate your pain initially after speech, however, it is not known if it caused unnecessary
injury. attention from the enemy. One patient developed a pe-
2. On a scale of 1 to 10, rate your pain with the riod of apnea after receiving ketamine and midazolam.
application of the tourniquet.
3. What caused more pain, the tourniquet or the injury? This was his second round of receiving ketamine and
4. Which one of the following best describes what you midazolam, after being moved through a pomegranate
remember after the injury? orchard. The move was made more difficult by the spo-
a. Remember nothing radic gunfire from the enemy and suppressive fire from
b. Remember pain or lack thereof attack helicopters; the patient was moving his extremi-
c. Remember being injured and who was around
d. Hallucinated ties throughout this time. Once the patient arrived at the
5. If you do recall pain after the administration of helicopter-landing zone, he was given his second round
ketamine, rate your pain on a scale of 1 to 10. of medication. Within 30–60 seconds of administration
6. If you do not remember or recall the time after the of both ketamine and midazolam, he stopped breath-
administration, when did you first realize you were ing. He was observed for 30–45 seconds before being
injured?
a. Before CASEVAC [casualty evacuation] aroused by painful stimuli.
b. During CASEVAC
c. Arrival at MTF [military treatment facility] The eight patients who responded to the questionnaire,
d. After surgery many reported vivid dreams, with one casualty noting an
almost out-of-body experience. He reported seeing him-
self from above with treatments being performed. He re-
application; (2) long-bone fracture due to penetrating ceived midazolam in conjunction with ketamine. Patient 7
trauma; or (3) extremity amputation. received two doses of ketamine as TCCC recommended;
prior to ketamine he had received morphine 15mg and
Along with ketamine, most patients with severe pain midazolam 7.5mg. Even with morphine, midazolam, and
received hydromorphone and/or midazolam. The ket- low-dose ketamine, he still had significant pain. Tourni-
amine dose used for these patients differed from case to quet pain was, by far, reported as the worst pain. Ampu-
case. During this time, the 75th Ranger Regiment did not tations closely followed. Most long-bone fractures were
have a standard protocol for ketamine use, and varying associated with tourniquet application, usually due to the
doses were given depending on the provider overseeing vascular damage and associated massive hemorrhage.
the medical personnel at the various combat outstations.
The discussion among the providers in the 75th Ranger It was noted by the authors and in personal commu-
Regiment prior to the release of the RMHB led to a nication with the treating medics that procedures were
unanimous recommendation of 50–100mg IV, but there easier to perform and it was easier to move patients who
were instances where it was given IM in larger amounts. had received ketamine. Procedures such as splinting and
reduction of fractures, and wound packing and dress-
ing were easier to perform with the sedating effects of
Results
ketamine. Excessive patient movements, such as moving
Of the 11 patients who received ketamine, two were lo- extremities and talking, were common when using ket-
cal nationals who were lost to follow-up. The remaining amine alone or with Dilaudid. The authors noted and in
nine cases were active duty Soldiers assigned to the 75th personal communication with the treating medics, when
Ranger Regiment. Although times were recorded in the using midazolam with ketamine, there was a drastic de-
PHTR, the administration times were not exact due to crease in extremity movements and incoherent speech.
the difficulty of maintaining precise time during ongo-
ing combat operations. It is estimated that the onset of
action of IV ketamine was 1 minute or less. Onset of Discussion
action for IM administration was less than 3 minutes. The doses of ketamine being administered in this patient
population appear to be safe and appear to have con-
The average initial dose for ketamine, when given IV was trolled the pain effectively. This dosing range is still far
65mg, when given IM was 183mg, with an average total below the recommended dose for surgery, but enough to
dose given IV was 97mg and IM was 217mg (Appendix cause analgesia and dissociation. The use of midazolam
B). All patients who received IV administration of ket- or dilaudid appeared to offer additional sedation and
amine received at least two doses. One patient received pain management.
two 100mg doses IM. Most of the side effects from the
administration of ketamine were extremity movements In this small study, ketamine appears to have improved
and incoherent speech. The extremity movement made pain scores without being associated with significant

Prehospital Analgesia With Ketamine for Combat Wounds 13