"Optimizing Combat Casualty Care"

Wireless vital sign monitor
approval enters final phase

Engineers and scientists at San Antonio's U.S. Army Institute of Surgical Research have developed a lightweight wireless vital signs monitor.

Engineers and scientists at San Antonio's U.S. Army Institute of Surgical Research have developed a lightweight wireless vital signs monitor. Photo by Steven Galvan

By Steven Galvan, Public Affairs Officer
U.S. Army Institute of Surgical Research
06 FEB 2012

Combat medics could soon have a new vital signs monitor device added to their first aid kits to help them accurately evaluate and track the condition of wounded warriors from the point of injury on the battlefield and throughout the medical evacuation process to an emergency room.

The FDA-approved Wireless Vital Signs Monitor (WVSM), designed by a partnership of the U.S. Army Institute of Surgical Research, the U.S. Office of Naval Research, and Athena GTX, began the final phase of approval in September with clinical trials at the Memorial Herman-Texas Medical Center emergency department and on the Life Flight air critical care medical transport service, both located in Houston, Texas.

The WVSM is a small, lightweight device that measures and records a patient’s electrocardiogram; heart rate; pulse oximeter; and non-invasive systolic, diastolic, and mean blood pressures. The information can then be transmitted to a medic’s laptop, smart phone or electronic tablet where it calculates additional patient information (e.g., trends, pulse pressure, shock index, heart rate variability and complexity indices, and the percentage probability of needing a life saving intervention using technology that incorporates artificial intelligence and advanced artificial neural networks).

“This device incorporates technology developed at the ISR to provide users with information on the patient condition, not just raw data from the patient sensors,” said Jose Salinas, Ph.D., Research Task Area Program Manager, Combat Critical Care Engineering at the USAISR. “It’s the first monitor that incorporates artificial intelligence and machine learning technology.”

The WVSM is strapped on to a patient’s arm or leg and captures all vital signs from the point of injury and is capable of transmitting and downloading the information to a hospital’s emergency department monitoring system. Unlike current monitoring devices that only provide medics with a basic set of vital signs, the WVSM tells medics when a patient’s condition is getting worse even though there aren’t outward physical signs.

“If a patient has lost a lot of blood, standard vital signs may not fully represent how he is doing,” said Salinas. “Our bodies compensate for blood loss through different mechanisms that can mask the true severity of the injury.”

The WVSM trial is being funded through a grant from the State of Texas Emerging Technology Fund and is being administered by the National Trauma Institute. This collaborative effort is also allowing engineers at the USAISR and the Army to develop the next generation of the WVSM by incorporating state-of-the-art computer technology with advanced digital signal processing algorithms to produce a new generation of smart vital signs monitors.

“We are working on making it better,” said Salinas. “We can expect a new version in one to two years.”

The current WVSM utilizes electronic wires to connect the pulse oximeter that attaches to a patient’s finger and the electrodes that are placed on the chest. These wires could get cut or damaged during treatment or while removing garments from the patient.

“The new version will eliminate these wires,” Salinas said. “This device and all of the research projects at the ISR are all aimed at optimizing combat casualty care and minimizing preventable death for our combat wounded.”

The USAISR is committed to optimizing combat casualty care by focusing on providing requirement-driven combat casualty care medical solutions and products for injured soldiers from self-aid through definitive care across the full spectrum of military operations.