A Basic Approach to Prehospital Management of Penetrating Trauma

It’s a warm Saturday night when your BLS unit is dispatched over the radio: “EMS 6, Code 1 assignment, corner of 14th and State, report of a stabbing, unknown extent of injuries. PD is en route, time out 19:42.” On the way, you try to recall any recent stabbing you have responded to, but none comes to mind. You hear that the PD is now on scene. They advise you that the victim has multiple stab wounds and ask for a “rush on EMS.”

You arrive to find a 24-year-old conscious male lying on his back, stabbed multiple times in the torso and abdomen. He is having a hard time telling you what happened and describing the location of his injuries. The patient’s radial pulse is thready and weak, and you realize he’s having a tough time moving air. You move the patient into the back of the ambulance, grab a quick set of vitals and begin rapid transport to the trauma center seven miles away. “Where’s the ALS unit?” you yell to your partner as your patient loses consciousness and goes into respiratory arrest.

Penetrating trauma may present as some of the most graphic injury patterns you will encounter in EMS. Penetrating trauma is defined as “an injury caused by an object breaking the skin and entering the body.”1 These events include gunshot wounds (GSWs) and stab wounds, as well as other types of impalements, and can range in severity from superficial punctures to penetration of major body systems. The greater the speed of penetration, the more severe the injury tends to be.

When responding to these emergencies, safety of the crew and patient must continuously be addressed, keeping in mind the type of incident and the potential for continued violence or additional traumatic injuries that could be directed toward the crew or other individuals on scene.

Categories of Injuries

While these injuries can occur from a variety of sources, we will focus specifically on weapons and low-, medium- and high-energy or velocity wounds.

Low Energy

Objects or nonballistic weapons like knives or ice picks used from a close distance cause low-energy injuries. While they can be life-threatening, it depends on the type of object used, location, depth of penetration and number of wounds. A single stab wound to the center of the chest with a kitchen knife is a higher life threat than eight stab wounds with a pocketknife to an extremity. While both are penetrating traumatic injuries, due to the mechanism of injury (MOI), we are able to identify a higher life threat with the kitchen knife because of its size and location of the injury.

Medium and High Energy

Bullets or other ballistic weapons typically cause medium- and high-energy, or high-velocity, wounds. Determinants such as the type of weapon, handgun vs. rifle, size of the projectile’s caliber and distance at which the weapon was fired are all critical to determining the potential extent of the injuries. When looking at these wounds, try to envision the pathway the bullets took once they entered the patient. Certain smaller-caliber bullets (.22 and 9 mm) tend to bounce around within the patient, increasing the extent of injury and potential for death. Larger-caliber handguns, like a .45 caliber, are designed to continue straight ahead and actually increase the pathway of injury until the projectile exits the body. This is due to a phenomenon known as cavitation, in which speed causes a bullet to generate pressure waves that result in damage distant from the bullet’s path. Resultant tissue injury can be many times larger than the diameter of the projectile.2

While it is not critical for EMS to immediately discern between medium- and high-velocity wounds, having this information will assist in the patient’s care at the local trauma center. For prehospital providers, the focus remains on scene safety, the ABCs and rapid transport to an appropriate facility.

Assessment

An EMS provider’s approach to penetrating trauma is fairly straightforward.

As you approach, begin your scene size-up. If it seems unsafe, don’t exit your vehicle. If you decide to approach, park your vehicle in a manner that facilitates an easy exit from the scene, and then start your general impression of your patients. Evaluate the mechanism of injury, number of patients and any potential hazards, and determine whether additional resources might be needed, such as EMS units to treat/transport multiple patients and police to preserve evidence and, more important, secure the scene from additional attempts to injure you or your patient. Try to determine the patient’s approximate age, potential MOI and obvious bleeding or injury even before talking to or touching him. Kneel next to the patient in a way that won’t cause him to quickly move his head to look at you and, in the process, exacerbate a cervical injury to the point of further injury, paralysis or even death. Immediately take spinal immobilization precautions, as the penetrating injury may have injured the cervical column or spinal cord. An example would be a patient exposed to the force of an explosion or its resultant projectiles. If a projectile hits the patient in the thoraco-abdominal area, cervical precautions should be taken. If the projectile caused an isolated extremity injury, however, the probability of spinal involvement is minimized. It goes without saying that spinal precautions only need to be taken when there is a high index of suspicion for such injury.

Next, assess the patient’s airway. Does the patient have a patent airway? If the answer is no, open the airway with the jaw-thrust maneuver to minimize further spinal injury. If the airway is full of fluid (probably blood or vomitus), suction the patient. Once the airway is clear, keep the airway in the open position, either manually or with adjuncts (oropharyngeal or nasopharyngeal airway). If there is trauma to the maxillofacial area, there is a potential for a skull fracture, which most protocols consider a contraindication for a nasopharyngeal airway. Check your local protocol on this.

Once the airway has been secured in the open position, assess breathing. If the patient is not breathing, immediately give two breaths and check for a carotid pulse. (Note: Some areas have protocols for withholding CPR secondary to trauma. Check your local protocols on this.) This CPR quick-check will indicate whether you need to start compressions or, if there is a pulse, to focus only on ventilations. If the patient is breathing, ascertain the rate. If the rate is too slow or too fast (many states use the national standard of below 8 or above 24), assist ventilations with a bag-valve mask. If the patient’s respiratory rate is between 8 and 24 breaths per minute, administer a high concentration of O2 via non-rebreather mask or BVM. It’s important to know that even though the respiratory rate is between 8 and 24, the patient can still become hypoxic as a result of hypoventilation. Consider tidal volume when determining treatment modalities— ALS or BLS—for injured patients. For that reason, you may also want to consider using a BVM in a patient with a “normal” respiratory rate.

During breathing assessment, inspect and palpate the chest for life-threatening injuries like a sucking chest wound or flail chest. These injuries need immediate intervention, even before assessing circulation. For a sucking chest wound, place an occlusive dressing over each penetration to the torso. Depending on local protocol, tape down all four sides or leave one side open (and three taped down) to allow air to escape from the chest cavity. Anytime there is potential for a punctured lung, apply an occlusive dressing. If your assessment reveals a flailed chest or segment of ribs, support it with a bulky dressing. Next, auscultate once on each side of the chest, listening at the mid-axillary position for air exchange. Detailed identification of specific lung sounds will be done later during the rapid trauma assessment. At this point, you are checking for the actual presence/absence of lung sounds and making sure they are bilateral. Prompt treatment of a flail chest or sucking chest wound can improve the patient’s ability to compensate from the traumatic event. If the respiratory system collapses, other body systems will start to shut down.

Following the ABC algorithm, look for significant blood loss and other associated signs of hemorrhagic shock. In addition to checking the voids along the posterior side of the patient, estimate blood loss into clothing, car seats, the ground, etc. Expose the patient to locate the origin of bleeding, and bandage the site of penetration. If bandaging does not adequately control bleeding, place manual pressure on the site of penetration and the local pressure point. This will slow down blood loss until the patient receives surgical intervention in the hospital.

Also check for bilateral radial pulses. If none are found, move toward the center of the patient; check the femoral and then the carotid. If no pulse is found at the carotid artery and your local protocols indicate it, start CPR. If a pulse is present, note the characteristics: Is it thready, weak, bounding or irregular? This will give you a better picture of the patient’s ability to compensate for the traumatic event and what stage of shock the patient is in. Some indications that the patient is not compensating well are labored or irregular breathing, falling blood pressure, thready or absent distal pulses, dilated or delayed pupillary response, and pale or cyanotic skin color. Implement methods to maintain the patient’s body temperature and elevate the lower extremities (if not injured) to help the patient compensate for the traumatic injury.

After evaluating the ABCs, you must make a transport decision. Will you stay on scene for a while longer or rapidly treat and transport the patient to the local trauma center? You will probably stay on scene for an isolated minor injury to an extremity (a nail puncturing a hand is not a life-threatening MOI).

Anything that needs attention in regard to airway, breathing or circulation must be addressed as the problems are found. Once this is accomplished, perform a rapid trauma assessment that includes exposure of all injured areas. While looking for primary injury, you may miss other important injuries, such as those listed in Table I. An example is the patient who was beaten and then stabbed. You may immediately see the stab wound and classify it as non-life-threatening, but further assessment will reveal an abdominal injury sustained during the assault. It is easy to see an open fracture or 10" facial laceration, but identifying other, less visible injuries and determining unexplained blood loss will depend on the thoroughness of your assessment. The location of a wound is a clue to potential damage of the underlying structures and organs.

All patients with multiple injuries should be completely undressed. This allows you to thoroughly survey the patient and identify injuries; however, don’t allow him to become hypothermic—keep him covered, when possible, and move to a warmed ambulance as soon as possible (both geriatrics and pediatrics lose heat rapidly when exposed, particularly if they are wet). If the patient is a victim of violent crime, try not to cut through areas of the clothing that may have entrance or exit wounds. Be aware of law enforcement’s evidence collection needs, but do what you need to expose injured areas.

Transport

Should all patients with penetrating trauma go directly to a trauma center? It’s important to know your local protocols in this regard. Some areas advocate going to the nearest hospital for traumatic arrest. This may also be the case for a patient with life-threatening trauma and an uncontrolled airway. Clinical indicators combined with time limitations and provider experience will assist in this sometimes-gray area.

Blunt and penetrating trauma have significantly different survivability rates. All patients with penetrating trauma must be evaluated by a physician—ideally, a trauma surgeon in a trauma center. If your region does not have a trauma center, consider transporting to the local ED, where they can stabilize the patient while aeromedical transport is dispatched to their facility.

Give advance notice to the receiving facility about the type of injury and the patient’s condition. Relay any information regarding the type of implement or weapon used to the receiving facility. For example: “24-year-old male, stabbed multiple times in the torso and abdomen with what appears to be a knife or other sharp object.” Keep it simple and to the point.

Conclusion

Wounds secondary to penetrating trauma are potentially the most gruesome that EMS providers will see. There are simple steps, however, that will allow providers an easy way to triage, treat and transport these patients in an effective manner.

It is in the best interest of all EMS providers to take a Basic Trauma Life Support (BTLS) or Pre-Hospital Trauma Life Support (PHTLS) course to gain more knowledge about all types of traumatic injury.

It’s critical for EMS providers to remember that trauma is a surgical injury with limited EMS interventions. Scene time and patient management play the largest roles in determining overall mortality. Understanding mechanisms of trauma and effectively dealing with traumatically injured patients are only some of the weapons in the EMS provider’s arsenal. Remember: Penetrating injuries are more than skin deep, literally and figuratively.

References

1 Bledsoe B, Porter R, Cherry R. Essentials of Paramedic Care, Chapter 16, p. 815. Prentice Hall, 2003.
2 American Academy of Orthopedic Surgeons. Emergency Care and Transportation of the Sick and Injured, 8th Edition, Chapter 21. Jones & Bartlett Publishers, 2001.