In 1996, a revolutionary concept occurred in military medicine. Until then, battlefield prehospital trauma care followed the same guidelines developed for the urban U.S. civilian environment. But following the October 3, 1993, Battle of Mogadishu1, the U.S. Special Operations Command sponsored a study to review how casualty care was conducted. The panel’s consensus: Conventional civilian medicine was not appropriate for optimizing casualty care within the tactical environment.
To that end, two military physicians with extensive tactical experience authored a set of guidelines intended to improve casualty care during tactical operations.1,2 These Tactical Combat Casualty Care (TCCC) guidelines have been consistently reviewed and updated, and are approved by the American College of Surgeons Committee on Trauma for inclusion in their Pre-hospital Trauma Life Support guidelines.3
A decade ago, we were attempting to apply civilian techniques to the combat environment; today, we’re examining the opposite: Are there lessons learned from tactical medicine that may improve or facilitate civilian prehospital trauma care? Although tactical medicine generally breaks down care by tactical situation (e.g., care under fire, tactical field care and tactical evacuation), this article will examine the issue by categories of trauma interventions.
Isolated extremity hemorrhage remains the primary cause of potentially preventable death during combat operations. Casualty care improvements, including better medical devices, guidelines and training down to the individual soldier level, have focused on decreasing this cause of mortality.
Another article within this supplement (“Tourniquet First!” p.24) explores temporary emergency tactical tourniquets in depth. For the purposes of this article, it’s simplest to point out that new tourniquets, and new guidelines for early tourniquet use in far-forward casualty care, are saving lives.4 The primary tactical tourniquet recommended by the U.S. Army Institute of Surgical Research (USAISR) is the Combat
Application Tourniquet (C-A-T), followed by the Special Operations Forces Tactical Tourniquet (SOF-TT). The Delphi Emergency & Medical Tourniquet (EMT) is the primary pneumatic tourniquet used with fixed surgical facilities and unit aid stations.5,6,7
Compression bandages are widely used throughout the military. Several new commercial products represent a significant improvement over older, non-compression style bandages. These newer devices all incorporate a non-adherent bandage in the form of an elastic wrap tail. Sequential wrapping of the elastic tail generates a compressive force that, when combined with gauze packing, creates an extremely efficient and effective pressure bandage. The Emergency Bandage by First Care Products was the first of these modern compression bandages to gain widespread acceptance.
The Emergency Trauma Dressing by North American Rescue (NAR) represents a significant design improvement over older devices.8 This elastic compression wrap is a tighter weave and generates greater compressive force. The wrap’s “Quick Grip” feature (Velcro® enclosures equally spaced along the wrap) prevents the entire wrap from unrolling prematurely if the wrap is accidentally dropped during application.
Certain wound locations—such as the proximal extremities, axilla, groin, torso and neck—make it difficult to control hemorrhage with direct pressure and compression dressings; tourniquets are also ineffective in many of these areas. Researchers have developed several new tools and clinical guidelines to address this critical issue. Over the past few years, a number of hemostatic agents, in both bandage and powder form, have been developed that actually arrest life-threatening arterial hemorrhage.9,10,11
The most recent research conducted by both the Army and Navy research centers compared more than 10 types of hemostatic agents for controlling arterial hemorrhage in animal models. One granular product (WoundStat, manufactured by Trauma Cure) was found to have a 100% survival rate for subjects with wounds that would otherwise be fatal. Another product, an improved gauze impregnated with a kaolin substance (Combat Gauze, manufactured by Z-Medica), demonstrated greater than 80% efficacy in independent lab presentations to the research committee. This product is actually a pro-coagulant that promotes blood clotting.
These newer hemostatic agents are proving to be both more effective and less expensive than those previously approved by the TCCC committee. In clinical trials, WoundStat showed the highest clinical efficacy, yet it is a granular-based product, which is problematic to adequately apply during tactical operations. Combat Gauze showed the next highest efficacy. Both were superior to the benchmark HemCon and QuikClot. Celox, a granular chitosan-based agent, also outperformed both HemCon and QuikClot in both USAIR and Naval Research Lab Studies. Note: This data was taken from the “Comparative Testing and Analysis of New Hemostatic Agents in Lethal Injury Models” presentation, which provides pre-published data from the Navy Research Lab and the Army Institute of Surgical Research to the TCCC committee.
However, Celox didn’t perform as well as WoundStat or Combat Gauze. It’s a lighter weight powder than WoundStat, which makes application to arterial hemorrhage injury difficult.
Based upon the results of these studies and input from combat medics regarding device preferences, the TCCC committee revised its recommendations. The newest guideline change is to utilize Combat Gauze as the primary hemostatic agent, with WoundStat as the backup or when the wound characteristics are more amenable to a granular agent.
Although mortality from isolated hemorrhage is not as high in the civilian community as it is in the combat environment, it does exist. Additionally, reducing the potential morbidity and cost of blood transfusion requirements by arresting hemorrhage early, at little to no risk to the patient or rescuer, is a huge potential benefit.
Many EMS agencies have been using hemostatic agents for some time with excellent results. The newer agents are far superior to the earlier ones and have come down in price. Why wouldn’t we want to place an additional tool in the EMT, paramedic and first responder’s toolkit that requires little training, is cost effective and has few side effects?
Airway & Breathing
Historically, tension pneumothorax and simple airway obstruction comprise the second and third most common causes of potentially preventable combat deaths. Penetrating trauma still remains the leading mechanism of injury during combat. Because the incidence of cervical spine injuries with isolated penetrating trauma is extremely low, obtaining and maintaining C-spine immobilization is neither practical nor advisable during the majority of tactical operations. Instead, soldiers are taught to place unconscious casualties in the lateral recovery position, thus minimizing the risk of airway occlusion from blood, vomitus or a flaccid tongue. When a casualty is placed in the prone position, the nasal pharyngeal airway represents the best choice for a simple airway adjunct.
When a more definitive method of airway control is required within the tactical environment, especially in the setting of facial trauma, most experts recommend the surgical cricothyrotomy as the procedure of choice. This complex, invasive procedure requires appropriate training under realistic conditions to maximize a rescuer’s chance for successful task completion.
Adequate tools are required to facilitate this procedure, one of the most important being a laryngeal hook. Although few surgical instruments are designed specifically for the tactical environment, NAR’s Tracheal Hook is one exception.
The Tracheal Hook is designed specifically to facilitate this surgical procedure under less-than-optimal conditions. Once an incision is made, the the small end of the Tracheal Hook is inserted into the cricoid cartilage and lifted up for stabilization and anterior displacement. This better exposes the hole opening for insertion of the tracheal tube.
NAR includes this Tracheal Hook in a complete, compact surgical cricothyroidotomy kit that facilitates rapid completion of this procedure under high-stress circumstances.
Other airway devices for the tactical environment remain controversial. Although retrospective casualty analysis is still being conducted, there has been no data supporting a clear survival benefit for supraglottic devices. Multiple prehospital studies have been conducted on these devices, but those studies did not account for the extent to which casualties are moved within the tactical environment.
Although the Laryngeal Mask Airway (LMA) has received many favorable reports from both the anesthesia and prehospital literature, military trauma providers are concerned that the devices are too easily dislodged during rigorous extractions and evacuations. The Army evaluated several devices and chose two: the dual-lumen CombiTube and the single-lumen King LT-D. Of these two devices, the King LT-D demonstrated a distinct advantage in terms of rapid, correct insertion over the CombiTube.12 Training novice users to correctly employ the King LT-D was easier, and the skill was retained for a longer period of time than with the CombiTube.13
Penetrating chest injuries represent a complex problem in the tactical environment. Traditional methods of patient assessment, such as visual inspection and auscultation with a stethoscope, are not always possible in a low-light, high-noise combat environment. Although medics are trained to locate and seal open chest wounds, securing an occlusive dressing to a sweaty, bloody, hairy chest to prevent air entry is not an easy task. Surgical tape doesn’t always stick, and fashioning bandages under duress is difficult.
As a result, a single adhesive dressing that effectively occludes a chest wall defect is a required item in the medic’s kit. The commercially available Asherman Chest Seal has been used by the military, but newer products, such as the Hyfin chest seal, offer more aggressive adhesive that keeps the pliable dressing in place throughout a rigorous evacuation process. Although the Hyfin chest seal does not feature a relief valve, tactical and civilian medics are well trained in recognizing and treating a tension pneumothorax.
Penetrating chest trauma is responsible for the second leading historical cause of potentially preventable combat death: tension pneumothorax.14,15 Combat medics are taught to have a very high suspicion for this problem when managing penetrating trauma, and to treat it with a needle thoracostomy. Although controversy exists regarding the efficacy of this procedure in civilian prehospital literature, combat experience shows it to be a life-saving procedure within the tactical environment.
Realizing that a needle thoracostomy is not a definitive treatment, combat medics are taught to use a 14-gauge by 8-cm (3.25") angiocath device to perform an invasive procedure that converts a life-threatening tension pneumothorax to a survivable simple pneumothorax.
Military rescuers are trained to utilize the 2nd or 3rd intercostal spaces, mid-clavicular line approach as their primary procedure, with adjustment to the anterior axillary line if the primary site is compromised or unsuccessful.
Needle thoracostomy will be successful only if the needle tip penetrates into the air pocket. Note: The 3.25" catheter is recommended because several studies confirm that the average adult chest wall is greater than 5 cm, and if the insertion angle is not perpendicular, that distance may increase by almost a full centimeter.16–18
NAR’s Air Release System (ARS) represents a significant advance in human-factors engineering for this simple device. Many systems use the typical angiocaths for this procedure, which have a flash chamber cap attached to the catheter assembly. Although this chamber cap prevents unnecessary blood loss when used to start an IV, it precludes the release of air when used in needle thoracostomy. Therefore, providers often fail to remove the cap on the standard angiocath when performing this procedure under duress.
When they insert an ordinary angiocatheter through the chest wall and fail to appreciate an improvement in the casualty’s status, providers assume the procedure wasn’t effective and remove the entire catheter assembly without having treated the underlying problem.
The ARS does not incorporate a flash chamber cap; thus, when a rescuer penetrates the chest wall into the pneumothorax pocket, there’s no additional step required to relieve the pressure. Air immediately escapes through the device, confirming successful placement.
TCCC guidelines emphasize a hypovolemic resuscitation algorithm. Combat medics are trained to evaluate combat casualties for hypovolemic shock, and initiate IV fluid resuscitation only after obtaining hemorrhage control. They assess the radial pulse character and mental status as clinical markers for IV fluid requirements.
Medical supply resources are extremely limited in the tactical environment, often constrained by what the medics can carry in their aid bags. IV fluids represent the heaviest component of all medical supplies, necessitating a fluid that provides appropriate volume expansion for the longest possible time. The military selected Hextend as the fluid of choice for hypovolemic resuscitation due to hemorrhage.
Medics are trained to secure IV access for combat casualties through the use of a saline lock device. The saline lock procedure is slightly modified from typical clinical applications in that, once secured, it’s accessed by a second IV catheter. This provides a measure of security to prevent accidental dislodgement and allows medics to administer IV medications when IV fluid resuscitation is not required.
Securing IV access via a saline lock is a technique used by many civilian prehospital services so they have IV access and don’t have to expend medical supplies to run IV fluids at a “TKO” rate.
When IV access is difficult to obtain in the hypovolemic combat casualty, medics use intraosseous (IO) devices to secure parenteral access.Military medics access multiple sites for rapid fluid administration, including the manubrium, tibia, humeral head and clavicle. The devices that have demonstrated superior efficacy in battlefield medicine include the Pyng FAST1 sternal intraosseous device and the VidaCare EZ-IO.19-22 Many civilian EMS agencies and hospital emergency departments have successfully incorporated these devices into their protocols. Note: A pressure infusion device must be used when administering fluids through an IO needle.
Evacuation & Transportation
Traditional manual carries and drags of non-ambulatory casualties depicted in numerous texts simply aren’t effective when rescuer and casualty alike are outfitted in full combat gear. Additionally, a tactical unit carrying evacuation platforms/stretchers into live combat can negatively impact maneuverability if the selected platform is too bulky or heavy for a single person to carry effectively.
The Talon II by NAR provides the material solution for this issue. Unlike non-rigid litters, the Talon provides a measure of patient safety by preventing excessive body movement, securing the casualty to the device via the integrated safety straps. In addition, over most terrain, moving a rigid litter requires much less effort than other types of platforms. The litter can then be secured directly to a vehicle or to a traditional movement gurney. Collapsible rigid litters are also easily stored in vehicles and occupy relatively little space.
Until fairly recently, hypothermia was a major source of morbidity among combat casualties. Even though ambient temperatures in combat areas often exceeded 100º F during daytime hours, casualties who had been previously exposed during evaluation and treatment were arriving at Combat Support Hospitals and Forward Surgical Teams profoundly hypothermic.
One retrospective review revealed that 18% of casualties evacuated to one hospital arrived with core temperatures of less than 36ºC.23 This study showed that the presence of hypothermia was an independent predictor of operative management, surgical procedures, Factor VIIa use and mortality, with temperatures of less than 34ºC associated with a near 100% mortality rate.
Acknowledging that active re-warming capability at the point of injury during tactical operations is not logistically feasible, military medical researchers turned their efforts toward hypothermia prevention. Traditional “space blankets” were found not to be effective enough; soldiers needed a small, lightweight product that could be easily carried in a medic’s aid bag, preferably without an external power source. The result was a system that incorporates a heat source with an improved insulator.24
NAR’s Hypothermia Prevention Management Kit (HPMK) is a vacuum-sealed compact kit that has proven very effective in preventing hypothermia. It was selected as one of the hot products at the 2008 EMS Today Conference.
Educating military rescuers on the importance of hypothermia and employing an effective kit virtually eliminated the incidence of hypothermia-related complications and mortality. The HPMK’s compact size and proven performance makes it an ideal candidate for consideration as a contingency item in civilian emergency vehicles and an important asset to have on hand in large quantities for use at MCIs.
Another challenge encountered during tactical operations: adequately medicating casualties in a timely manner. When casualty evacuation delays occur, the timely administration of antibiotics is crucial for the prevention of subsequent wound infections.
One product that addresses both moderate pain control and antibiotic prophylaxis is the Combat Wound Pill Pack, a “homemade” packet that Special Operations Forces use consisting of acetaminophen, meloxicam and a flouroquinolone. The combination of acetaminophen and meloxicam provides analgesia for mild to moderate pain without altering the sensorium, thus allowing the operator to continue participating in the tactical mission.
Military medical providers have also successfully used oral trans-mucosal fentanyl devices for pain management during combat operations. These devices have the advantage of rapid onset of action, significant pain-control properties, not requiring IV/IO access and the ability to be self-administered and titrated.25 Although not required for every trauma patient, such devices certainly bear consideration for use as a viable option in civilian prehospital and emergency department pain-control protocols.
Military medicine has contributed to many advances in prehospital trauma care by applying sound medical principles to account for the challenging tactical environment. These advances were achieved due to the requirement to optimize casualty care while simultaneously minimizing the impact on ongoing combat operations. Although all these applications may not be appropriate for the contemporary civilian environment, we should examine current military tactical medical techniques and procedures for possible crossover benefit to our civilian trauma patients, or as areas that may require further study.
Dr. Jeffrey Cain is an emergency medicine physician practicing in McKinney, Texas. He is a graduate of West Point and the Uniformed Services University of the Health Sciences, with service in the 75th Ranger Regiment as an infantry officer and later as a battalion physician. Other active-duty Army assignments included academic director for the Army Combat Medic Course and research physician with the U.S. Army Institute of Surgical Research. He has conducted extensive TCCC training for the Department of Defense and other government organizations, and is currently serving as the vice chairman for the Committee on TCCC. Cain has reported receiving honoraria and/or research support, either directly or indirectly, from the sponsor of this supplement, North American Rescue.