Page 85 - JSOM Fall 2020

TABLE 3 Ketamine Training Casualty Dosing (mg) per Dose
Number of
Dose Casualties Mean (SD) 95% CI* Range (mg) Minimum Dose (mg) Maximum Dose (mg) IQR
1 34 47.35 (26.263) 38.52–56.18 105 15 120 28
2 19 62.89 (60.903) 35.51–90.28 265 10 275 75
3 7 23.57 (12.488) 14.32–32.82 40 10 50 5
4 3 26.67 (20.817) 3.11–50.23 40 10 50 —
5 1 10 (0) — 0 10 10 —
6 1 10 (0) — 0 10 10 —
Total** 34 1.88 (1.094) 1.51–2.25 5 Doses 1 Dose 6 Doses —
*Due to sample sizes <30, variations may be noted with 95% CI calculations and SD should be considered.
**Data regarding number of doses received, not dosage (mg) of ketamine.

TABLE 4 Ketamine Administration Routes (N = 34)
Initial Administration Route Additional Administration Route Administration Route Totals
Route Number of Casualties % of Casualties Route Number of Casualties % of Casualties Number of Casualties (%)
IM 10 29.4 IM 2 5.9 12 (35.3%)
IN 8 23.5 IN 0 0 8 (23.5%)
IO 0 0 IO 0 0 0 (0%)
IV 16 47.1 IV 6 17.6 22 (64.7%)
— — — N/A 26 76.5 —
IM = intramuscular, IN = intranasal, IO = intraosseous, IV = intravenous, N/A = not applicable/no additional route.

patients whose initial dose was IM and the mean dose was There were no significant adverse reactions regarding hemo-
37.00mg (SD 18.135; 95% CI, 25.76–48.24). Last, 8 (23.5%) dynamic or respiratory compromise. Among the 34 patients in
of the patients received their first dose of ketamine IN, with the the study, 7 (20.58%) had potentially adverse reactions (Table
mean dose being 58.13mg (SD 27.247; 95% CI, 39.25–77.01). 8). Of these seven patients who had potentially adverse reac-
tion, 1 (2.94%) was noted as having a “mild emergence reac-
Patients’ pain assessment was based on a 0-to-10 pain scale, tion” and the casualty stated after discharge that “it wasn’t
with 0 being no pain and 10 being the worst pain of their life. that bad.” One (2.94%) experienced a “possible hypertonia
Four cases were not included because the data was incomplete; adverse event.” Other noted reactions were hallucinations,
therefore, the data for 30 patients were evaluated. Due to the amnesia, and potential hypertonia. There were 4 (11.76%) pa-
limited population size, and the data not being normally distrib- tients noted to have experienced hallucinations and 3 (8.82%)
uted, nonparametric testing was used to determine if there was who experienced amnesia. None of the reactions were noted
any significance between the pre- and post-ketamine pain scales. to have interfered with the patients’ care and were ultimately
well tolerated.
A Wilcoxon signed-rank test examined the results of the pa-
tients’ pre-ketamine pain scale and post-ketamine pain scale. Discussion
A significant difference was found in the results (Z = –4.791,
p < 0.05). The post-ketamine pain scale results were better In our experience the use of ketamine was safe and effective
than pre-ketamine pain scale results. This significance demon- in the military prehospital training environment. The idea that
strates that ketamine was effective in contributing to the relief inexperienced, young medics could have the clinical judgement
of the patients’ pain. The median pre-ketamine pain scale for to titrate morphine in a polytrauma patient in the prehospi-
patients was noted to be 8.0 (IQR 3) and the median post- tal setting is unrealistic. In the early years of the conflicts in
ketamine pain scale was 0.0 (IQR 3) (Table 6). Other medica- Iraq and Afghanistan, morphine was often the only analgesic
tions were also provided to some of the casualties. option. It is concerning that morphine is still routinely used
1
by the US military, despite the CoTCCC recommendations,
Among other medications given were midazolam, hydromor- which are 5 years old. The approval to use ketamine as an
1,4
phone, ondansetron, midazolam and oral transmucosal fen- analgesic was important to improve the therapeutic index for
tanyl citrate (OTFC) (Table 7). Midazolam was administered battlefield medics for pain control because of the deleterious
the most, a total of 15 times (51.72%), via multiple known effects of morphine on blood pressure, gag reflex suppression
routes: IM, IN, and IV. IM was used for three (8.82%) patients and respiratory depression in trauma patients. 1
with a mean of 4.667mg (SD 0.577; 95% CI, 4.01–5.32).
Three (8.82%) patients also received IN midazolam with a Unfortunately, the data collection method did not capture pain
mean of 2.10mg (SD 0.361; 95% CI, 1.69–2.51). The most reduction with each dose, only the overall pain scale reduc-
prevalent route of midazolam was via IV whereby 9 (26.47%) tion. Likely, the majority of additional doses were due to re-
of the patients received midazolam, with a mean of 2.11mg dosing as the analgesic effect wore off. The measure of pain is
(SD 0.546; 95% CI, 1.75–2.47). There were three occurrences subjective and often difficult to assess and quantify. Though
of 2mg hydromorphone IV being administered, and 800 µg the pain scale is used routinely in studies and clinical care, it
oral transmucosal fentanyl citrate lozenge (OTFC) was given is still not an accurate tool for determining a consistent and
eight times. With regard to all the patients who received ket- accurate measure of pain due to the subjective variance of pain
amine, there were limited potential adverse reactions. perception between patients. Despite this, pain management

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