Contingency aeromedical staging facility (CASF) team members prepare a critical care patient for transport on C-17 Globemaster to Landstuhl, Germany where he will receive further care for his wounds.

AAOS Now

Published 7/1/2007
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Peter Pollack

Wound management, evacuationkey in treating battlefield injuries

During the second Extremity War Injuries symposium, combat physicians shared techniques in transporting patients from war zones to the United States

Approximately 70 percent of all traumatic combat wounds in Afghanistan and Iraq involve orthopaedic injury to the extremities, which present significant challenges for transporting these patients from overseas battlefields to definitive care in the United States. As military surgeons improvise and refine effective treatments, the lessons they’ve learned can be helpful for civilian—particularly rural—healthcare providers who may also have to transport severely wounded patients long distances.

That kind of synergistic learning was just what the organizers of the Extremity War Injuries II symposium hoped to generate. The two-day program, sponsored by the AAOS and the Orthopaedic Trauma Association earlier this year, focused on the development of clinical research principles aimed at promoting recent advances in managing traumatic extremity injuries.

Managing injuries for evacuation
According to Col. John V. Ingari, MD, penetrating trauma from blasts has been the most common mechanism of injury in recent conflicts, followed by gunshot wounds. The surgeon’s treatment decisions must take into account rapid air evacuation—a 6-hour flight within 24 hours of initial injury—to optimize limb salvage.

As a result, initial management of these traumatic limb injuries requires “efficiency, thoroughness, and meticulous attention to detail.” Once a history identifies the mechanism of injury and other coexisting trauma, and standard resuscitation protocols are satisfied, the field surgeon makes a determination between limb salvage and amputation. Limbs determined to be nonviable are amputated immediately.

Viable limbs undergo thorough irrigation and débridement of all devitalized tissue and foreign materials. Physicians do not perform primary skin closure but apply a “ridiculously bulky” dressing to open wounds for transport. Fasciotomies are done “early and often” to maximize limb viability during and after the evacuation flight and to prevent the development of compartment syndrome in the limb.

The use of external fixators, which can span open fractures with significant tissue loss, greatly facilitates limb salvage for viable extremities. They immobilize the wound and enhance patient comfort during transportation. As a result of these techniques, explained Dr. Ingari, less than 5 percent of patients arriving at Landstuhl, Germany, from battlefields in Iraq or Afghanistan required fasciotomy for evolved compartment syndrome during transport.

Rapid evacuation
Col. Elisha Powell IV, MD,
continued the theme of rapid evacuation of patients from the battlefield. In his view, the focus of combat medical treatment has shifted toward transporting patients quickly to a more capable facility rather than attempting to stabilize them near the combat zone. As recently as 1991, it took an average of 10 to 14 days to transport a patient from Iraq to the United States; today, the average is just 3 days.

That change in focus has resulted in the formation of Critical Care Air Transport Teams and the need to address treatment in the partial-pressure environment of flight. As an example, he cited negative pressure wound management, which has revolutionized soft-tissue wound treatment, but is only now being studied in the aeromedical system.

Contingency aeromedical staging facility (CASF) team members prepare a critical care patient for transport on C-17 Globemaster to Landstuhl, Germany where he will receive further care for his wounds.
Tech. Sgt. Stacy Foster, air evacuation operations officer from the 332nd Expeditionary Air Evacuation Flight, gives a thumbs-up to airmen preparing to board a C-17 with an injured soldier. (U.S. Air Force photo by Airman 1st Class Nathan Doza.)

Because wounds caused by high-explosive blasts may be at increased risk for the formation of deep vein thrombosis/pulmonary embolism (DVT/PE), the Joint Theatre Trauma System staff has developed clinical practice guidelines. According to Dr. Powell, the guidelines include the use of Lovenox®, sequential compression devices, and inferior vena cava filters as options. Following this systematic prevention strategy can reduce the risk of DVT/PE in 90 percent or more of surgical and trauma patients without additional risk factors, said Dr. Powell.

The key to pain management
“Pain management, even on the ground, can be a complex issue,” said Lt. Col. Tracy L. Popey, MD. “With the stressors of flight added in, it becomes an even bigger problem.” Among those stressors are lower air pressure, noise, vibration, lack of humidity, and temperature control (too cold/hot).

Oral narcotics with parenteral boluses are a mainstay, and patient-controlled analgesia (PCA) during flight is becoming an option. The PCA is administered intravenously or into a nerve sheath through a peripheral nerve catheter. “The key to pain management during air evacuation is the recognition that pain medication requirements in the air are frequently double or triple what they would be on the ground,” said Dr. Popey.

On long flights, dressings and splints are also considerations that must be addressed. Because it is rarely possible to change dressings in-flight, dressings should be able to contain wound drainage for at least 12 hours. Dressing options include dry or wet-to-dry dressings, negative pressure dressings, and antibiotic-impregnated bead pouches (not generally used outside of the United States for American service members).

Options for splinting include plaster splints and external fixators, depending on the stability of the underlying injury and the need to address soft-tissue wounds. Traction that requires a swinging weight is not possible under evacuation conditions.

Fracture stabilization
Maj. Greg M. Osgood, MD,
discussed the realities of fracture stabilization in the field. Compact sterile instrumentation packages have simplified the application of external fixators on or near battlefields, so patients arrive at Level 3 facilities (behind the battlefield) with wounds that are better stabilized and managed.

Some fracture patterns, however, do not lend themselves to simple external fixation. Furthermore, the application of external fixators near the front lines is usually done without the benefit of fluoroscopy, often resulting in suboptimal pin placement and possibly resulting in incomplete fracture reduction.

Because many orthopaedic surgeons who are deployed to war only rarely see the types of wounds seen at field hospitals, Dr. Osgood advocated the creation of guidelines to familiarize them with the decisions and techniques involved in the early echelons of combat trauma. Such guidelines would address not only optimal techniques of fracture stabilization and safe placement of fixator pins, but would also discuss the effect of the field surgeon’s decisions on fracture fixation and the impact of frame application on wound care and patient transport.

Given the prevalence of ortho-paedic extremity trauma among wounded soldiers returning from Iraq and Afghanistan, orthopaedic surgeons both in the United States and abroad become invaluable links in the chain of recovery. Events such as EWI II give military and civilian researchers and surgeons the opportunity to understand the steps involved in removing the wounded from the battlefield and the reasons behind the treatment methods applied in the critical first hours and days after injury.