By Kelly Sullivan, USARIEM Public AffairsSeptember 17, 2013
NATICK, Mass. (Sept. 17, 2013) -- It is no secret that Soldiers must prevail in all kinds of terrain and climates to complete missions. Afghanistan, for example, boasts mountains with elevations higher than 24,000 feet.
Many Soldiers who have deployed to high altitudes without the proper time to adjust have learned the hard way that they are probably going to get sick.
"Rapid ascents without sufficient time to adapt to altitude can lead to acute mountain sickness, or AMS," said Dr. Stephen Muza, acting division chief for the Thermal and Mountain Medicine Division, or TMMD, which is part of the U.S. Army Research Institute of Environmental Medicine, or USARIEM. "This condition, marked by nausea, fatigue, headache and gastrointestinal distress, can really throw a wedge into a mission when not planned for."
Abrupt exposure to high altitude negatively affects mental and physical performance and overall health because it lowers the oxygen supply to the body's tissues for a significant amount of time. This condition, known as hypoxia, is what leads to altitude sickness.
"You also see a performance decrement at altitude," said Muza. "A Soldier may not be able to carry as heavy a load as they are used to or even march at speed."
This summer, like many summers before, researchers from USARIEM's Thermal and Mountain Medicine Division traveled to Pikes Peak in Colorado, to study the physiological effects of AMS.
"Soldiers have to perform in the mountains," Muza said. "We know lack of oxygen impairs health and performance. Currently, we are developing a tool that will give commanders a validated predictive model that accurately tells them at what point a Soldier may feel the effects of AMS and the likely severity of the symptoms."
Annually, researchers from TMMD make the trek to perform research at Pikes Peak because it allows them to validate the studies they conduct in the altitude chamber in Natick, Mass., while replicating a forward operating base environment similar to ones in Afghanistan. Also, Pikes Peak has what Muza calls the "ideal research elevation" of 14,000 feet, allowing for significant impairment without making people dangerously sick.
This year's study concluded a two-year study. Researchers from USARIEM collected data on 70 men and women who were exposed to four different altitudes, at different activity levels, to validate their previously published predictive model of AMS, which suggested that altitude, time at altitude, gender and physical activity level are significant predictors of AMS.
Researchers were also there to collect data to develop an altitude acclimatization model as part of the Altitude Readiness Management System, or ARMS, being developed. This system will contain three models: the validated AMS model, the altitude acclimatization model and a physical performance model.
"USARIEM has the world's largest mountain medicine database," said Dr. Beth Beidleman, a research physiologist for TMMD, and the primary investigator for this study. "By using the wealth of historical data combined with the studies we have done at Pikes Peak, we have been able to pool information and create this important system."
Prior to this, there was no test that could predict an individual's likelihood of getting altitude sickness. So the researchers at TMMD came up with the idea to create a model that would significantly help planners and commanders when they are planning missions.
The ARMS combines population-based data with an individual's altitude exposure, providing useful information for sustaining health and improving performance. It does this by predicting the prevalence and severity of altitude stress by incorporating altitude acclimatization, acute mountain sickness and physical work performance decrements. Simply put, it predicts the level of AMS a person is likely to experience during a mission and provides actual ways to reduce the severity and potentially avoid the affects of AMS altogether.
The first AMS model will allow commanders to identify the likely probability and severity of Soldiers experiencing AMS based on the mission requirements. If the risk and severity are too high, the altitude-acclimatization model will then enable commanders to mitigate the risk of AMS by developing an altitude-acclimatization prescription to avoid the harmful effects.
"This model allows commanders to mitigate the impact of altitude exposure," Beidleman said. "It not only predicts whether a Soldier would get ill at certain altitudes, it gives a prescription for exposure. This tool can prescribe, for example, that if (Soldiers spend) two days at 8,000 feet before they go to their final altitude of 14,000 feet, the likelihood and severity of AMS would be drastically reduced."
When this patent-pending technology debuts, the goal is to have produced a stand-alone software product coupled with the capability to produce a device version integrated into a wristwatch, GPS or smartphone.
"We are currently collaborating with Massachusetts Institute of Technology's Lincoln Laboratory to get this technology into a smartphone-based application," Beidleman said. "It is important for us to provide a really basic planning tool that anyone could easily use while planning missions."
Putting a good planning tool in the hands of commanders and unit leaders, enabling them to better complete their missions, is the primary planning consideration to Beidleman while perfecting this tool.
"If a commander has a small unit of 12 Soldiers with specialized skills, and potentially two can get sick, that really impacts their mission," Beidleman said. "With this tool, he or she can think ahead to bring an extra person or allow for more time for Soldiers to acclimatize to the altitude. Essentially, it tells them the risk and also provides them with ways to mitigate that risk."
The U.S. Army Research Institute of Environmental Medicine provides solutions to optimize warfighter health and performance through medical research. Located in Natick, Mass., USARIEM is recognized by the Department of Defense as a trusted leader in medical research for warfighter health and performance.