Page 21 - JSOM Summer 2024

TABLE 2 Tube Thoracostomy Patient Prehospital Interventions extremities, abdomen, and head/neck. Overall, 70% (1,507)
(n=2,178) of the casualties were partner forces or humanitarian non-
Intervention No. (%) combatants. The lower numbers of U.S. military members
Chest seal 73 (3) (26%) requiring tube thoracostomy placement is most likely
Tube thoracostomy 130 (6) secondary to personal protective equipment, tactics, or other
Needle decompression 276 (13) factors. Future studies should compare the U.S. and non-U.S.
cohorts to ascertain reasons for potential differences in tube
Limb tourniquet 416 (19) thoracostomy placement practices.
Intraosseous access 228 (10)
Intubation 208 (9) Chest interventions were not as common as might be expected;
Any blood product 115 (5) only 3% of casualties underwent chest seal placement. Prior
Crystalloid 67 (3) investigation from the Prehospital Trauma Registry (PHTR)
Ketamine 241 (11) identified only 46 (7%) casualties with chest seal placement.
Fentanyl 412 (19) This study was limited by the inherent reporting issues of the
Morphine 347 (16) PHTR. 12,13 The low numbers are likely due to poor reporting
Antibiotic 216 (10) or might be due to a larger number of casualties who experi-
enced a blast injury without penetrating wounds, the complex
nature of severely wounded casualties, and the limited diag-
(95% CI 63–65) (Table 3). The mean pulse rate was 112 beats nostic capability for tension pneumothorax in the prehospital
per minute (95% CI 111–113) and the mean respiratory rate environment. Of the invasive thoracic procedures, 6% (130)
was 24 breaths per minute (95% CI 23–24). The median ox- had a prehospital tube thoracostomy placement and 13%
ygen saturation was 97% IQR 93%–99%), and the median (276) had a prehospital needle thoracostomy placed.
Glasgow Coma Scale (GCS score) was 10 (IQR 3–15). Within
this population, 29% (624) underwent transfusion (Table 4). The signs and symptoms of tension pneumothorax often take
longer than anticipated to present and/or these casualties may
TABLE 3 Emergency Department Observations have had a hemothorax. Roberts et al. found that in sponta-
Observation Mean (95% CI)* neously breathing patients with tension pneumothorax, over
Systolic blood pressure, mmHg 112 (111–113) 50% developed hypotension between 5 and 180 minutes of
onset. Another systematic review stated the time from occult
14
Diastolic blood pressure, mmHg 64 (63–65) pneumothorax to development of tension pneumothorax can
Oxygen saturation, %, median (IQR) 97 (93–99) be assumed to be 30–60 minutes. This suggests patients com-
15
Glasgow Coma Scale score, median (IQR) 10 (3–15) pensate well or the time required to cause tension physiology
Pulse rate, beats per min 112 (111–113) is longer than combat medics/corpsmen anticipate. Eastridge
Respiratory rate, breaths per min 24 (23–24) et al. noted only 11 (1.1%) deaths due to tension pneumotho-
16
*Unless otherwise specified. rax in the prehospital setting. It is not necessarily surprising
that the prevalence of tube thoracostomy is lower than ex-
TABLE 4 24-hour Fluid Administration Data (n=624) pected when compared with needle decompression, given the
skill is often limited to medical officers or special operations
Fluid Median (IQR) forces (SOF) enlisted medical personnel.
Crystalloid, mL 3,850 (2,000–6,790)
Colloids, mL 0 (0–500) In the prehospital setting, if the signs and symptoms of ten-
Whole blood, units 0 (0–0) sion pneumothorax are present, needle thoracostomy, tube
Packed red cells, units 4 (0–10) thoracostomy, or simple thoracostomy may alleviate tension
4
Platelets, units 0 (0–1) physiology. In a recent study of 28,950 combat casualties,
Fresh frozen plasma, units 4 (0–10) needle thoracostomy was performed in 1.6% (486) and tube
7
thoracostomy in 1.1% (326). This low number is likely a
combination of rapid evacuation and data capture issues in-
Discussion
herent to the DoDTR. In this study, while only 130 under-
Casualties who underwent tube thoracostomy placement went prehospital tube thoracostomy, this may occur more
within 24 hours of admission were severely injured with lower frequently in multi-domain operations/large-scale combat op-
survival than reported in previous studies. They tended to erations (MDO/LSCO) scenarios. There are no specific studies
3,6
have multiple injuries, complicating prehospital care. While on tube thoracostomy by the combat medic/corpsman. Prior
chest procedures and limb tourniquets were the most com- studies from civilian emergency medical services (EMS) have
mon prehospital interventions for patients receiving a tube demonstrated similar outcomes compared to hospital-based
thoracostomy in 24 hours, it remains unclear whether these interventions. If needle thoracostomy is performed, it is likely
interventions were beneficial or contributed to indications for a patient will require tube thoracostomy at some point ; how-
17
tube thoracostomy placement. ever, failure rates for needle thoracostomy are high, 18,19 and
simply performance skill should not be an indication for tube
20
On arrival at the Medical Treatment Facility most of the pa- thoracostomy. Notably, tube thoracostomy, is more effective
tients in our study were tachycardic, normotensive, and tachy- at releasing air and has a stronger association with clinical and
pneic with a median GCS score of 10. A significant proportion vital sign improvement. 18,19,21
of these patients suffered from injuries due to explosive mech-
anisms, which was likely a factor in the number of serious inju- During the conflicts in Afghanistan and Iraq/Syria, the goal
ries in body regions beyond the thoracic region, including the was rapid transport away from the point of injury (POI). In

Combat Chest Tubes | 19