For the EMT exam, you will need to familiarize yourself with injuries of the circulatory system. Two types of injuries you should know are injuries to the heart and injuries to the vasculature.
Injuries to the heart
The heart’s function as a pump can’t be overstated; even a small bruise can cause diminished cardiac output. Check out this information about potentially serious injuries.
| Problem | Signs and Symptoms | Action Steps |
|---|---|---|
| Myocardial contusion | Possible irregular heartbeat; signs of a myocardial infarction or acute coronary syndrome such as chest pressure or discomfort, radiating pain, shortness of breath | Provide oxygen to maintain saturation; monitor vital signs closely |
| Commotio cordis | Sudden cardiac arrest caused by a sharp blow to the sternum from an object like a baseball, bat, or fist | Begin CPR immediately and apply an automated external defibrillator (AED) as soon as possible (ventricular fibrillation is the common presenting rhythm disturbance) |
Injuries to the vasculature
Rising up from the left ventricle, the aorta is a very large artery that carries blood away from the heart to the rest of the body. It quickly creates the aortic arch, causing it to descend toward the feet. The brachiocephalic, left common carotid, and left subclavian arteries branch off the aortic arch. Collectively they’re known as the great vessels.
![[Credit: Illustration by Kathryn Born, MA]](https://www.dummies.com/wp-content/uploads/439728.image0.jpg)
The arch is held up by the ligamentum arteriosum. In major blunt-force trauma, this ligament can act like a knife, causing a tear in the aorta.
Lacerations to the great vessels, or the vena cava, from either blunt or penetrating trauma, cause massive bleeding into the chest cavity. Your patient may appear in severe shock, even though there’s little or no external bleeding! Treat for shock and prepare to ventilate the patient if needed.
Lacerations to other major arteries or veins near the femur or in the neck also cause significant bleeding, either externally or internally.
Specific to the neck region, an open wound can potentially draw air into a vein or artery, causing an air embolism to occur. Just as you would do with an open chest wound, you cover an open neck wound with some type of occlusive dressing.
Normally, fractures of long bones don’t cause major bleeding. However, a broken femur can puncture the femoral artery lying next to it and cause massive bleeding that may require a tourniquet to control. Similarly, bleeding resulting from fractures of two or more long bones, like the tibias of both legs, can become fairly significant when added together.
Controlling any major bleeding you can see is essential. Without adequate blood the body can’t transport oxygen very well. Fortunately, the steps to control external bleeding are simple:
Apply direct pressure with your gloved hand using gauze or any clean dressing to cause blood to form a clot at the site.
If direct pressure fails to control the bleeding within a few seconds, apply a tourniquet proximal to the injury site.
You may have learned about applying a pressure point or elevating an extremity before applying a tourniquet; these techniques have not been shown to be effective.
You can control external bleeding, but you can’t control internal bleeding; the definitive treatment in the field is to rapidly recognize signs of shock, package the patient for safe transport, and move immediately toward a trauma center for surgical intervention.
Some trauma exam questions check whether you know how to properly perform a procedure. See if you can answer this one.
A 17-year-old female was stabbed several times during a fight. She has a 1-inch stab wound to the left side of her neck, which is oozing blood. There is an incision to her left hand, covered with a shirt, which bleeds freely when the shirt is removed. What should you do first?
(A)Use direct pressure to apply a dressing to the hand injury and elevate it above the heart.
(B)Use mild pressure to apply a dressing to the neck injury.
(C)Apply an occlusive dressing to the hand injury.
(D)Apply an occlusive dressing to the neck injury.
The correct answer is Choice (D). Although controlling the bleeding from the hand injury, as noted in Choices (A) and (C), may be tempting, the bleeding appears controlled when the shirt is left on the hand.
More importantly, the neck incision has the potential to create an air embolism, so occluding the site as soon as possible is imperative. A gauze dressing can’t block the site completely, which makes Choice (B) less effective than Choice (D).