Multiple casualties in the tactical environment or a disaster area that exceed both human and materiel resources require rescuers to triage rapidly, so the limited resources may be used for the most critical casualties. In the tactical environment, one may have to do so under fire, thereby increasing the chance of sustaining injury. In disaster zone, precious time may be wasted by attempting to access and treat vocal casualties, while delaying treatment for higher priority patients. Nonetheless, current methods for triage require rescuers to assess casualties one-on-one, delaying further the time to locate, triage and treat the most critical. A recent article in The Army Department Medical Journal succinctly captured the crux of problem noting:
Physiologic status assessment in casualties can be problematic in the military setting, where physical access to the injured individual may be complicated by terrain, weather and hostile action. Likewise, some civil sector settings may challenge first responders, particularly when victims are located remotely. The lack of a remote triage capability may therefore result in the medic attending to either a) a Soldier who is uninjured but caught in the vicinity of combat; or b) a Soldier under severe fire who has an injury that is deemed unsalvageable. Indeed, a combat medic may place himself in harm’s way to assist a Soldier who may not even be injured or may be unsalvageable. Data collected during the Vietnam War indicate that the fatality rate of US Army medics was double that seen in infantrymen.1
There is an initiative to remedy this situation within the Departments of Defense and Homeland Security. DHS, in cooperation with Boeing and Washington’s School of Medicine in St. Louise, developed a “Standoff Patient Triage Tool” in 2009 that allows a rescuer to assess pulse, body temperature and respiration. As the article from Science Daily notes, “The magic behind SPTT is a technology known as Laser Doppler Vibrometry, which has been used in aircraft and automotive components, acoustic speakers, radar technology, and landmine detection. When connected to a camera, the vibrometer can measure the velocity and displacement of vibrating objects. An algorithm then converts those data points into measurements emergency medical responders can use in their rapid assessment of a patient’s critical medical conditions.”2 Although the technology is not yet available, it is an interesting approach.
In addition to the above-mentioned, the US Army is currently seeking technologies that will allow them to have stand-off monitoring capabilities. Researchers seek to assemble a system that is functional from a human factors perspective (i.e., Soldiers will wear it and it will not hindered the mission) and useful with regard to discerning physiological signs of hemorrhage from normal combat stress. For instance, mental status and blood pressure, while useful, are unreliable indicators of hemo-dynamic stability.1 Moreover, they take time to gather. Researchers have therefor sought other “markers” that one can use to discern hemorrhage from stress. To this end, they investigated ECG readings, which can be attained remotely. Unfortunately, the readings are not sensitive enough. Another alternative is using “energy monitors” and algorithms that can detect physiological changes. The challenges are many, however. Location of monitors, for example, require Soldiers to have an uninjured limb. In the age of IEDs, this may be difficult, though researches found that in all but 6% of reported casualties an arm was viable for monitoring.
While technological challenges remain, the ability to quickly triage casualties in a tactical or civil disaster scenario is becoming more likely. Although these futuristic Star Trek device or Soldier-worn monitors lack feasibility currently, researchers are getting closer.
1. Ryan K, Rickards C, et al. Advanced Technology Development for Remote Triage Applications in Bleeding Combat Casualties. The Army Medical Department Journal. 2011;4/5/6:61-71.
2. Department of Homeland Security. “Triage Technology With A Star Trek Twist: Tricorder-like Device.” ScienceDaily, 1 Jun. 2009. Web. 8 Nov. 2012.