PHLS Level 1 Curriculum
Circulation & Hemorrhage Control
Circulation & Hemorrhage Control
Uncontrolled hemorrhage is the leading cause of preventable death in trauma. In the <C>ABC approach, catastrophic (exsanguinating) hemorrhage must be controlled before even addressing the airway.
The Lethal Triad of Trauma
When a patient bleeds significantly, they enter a physiological death spiral known as the Lethal Triad:
- Hypothermia: Blood carries heat. Losing blood means losing core temperature.
- Acidosis: Poor perfusion leads to lactic acid buildup.
- Coagulopathy: Cold, acidic blood loses its ability to clot.
Types of Bleeding
- Arterial: Bright red, spurting, pulsatile. Immediate life threat.
- Venous: Dark red, steady flow. Can still be life-threatening if a major vein is severed.
- Capillary: Oozing, easily controlled.
Stepwise Hemorrhage Control
Follow the tactical approach to bleeding control:
1. Direct Pressure
Apply firm, sustained, continuous direct pressure over the bleeding site using a sterile dressing. Do not peak to check the wound every 10 seconds—pressure must be sustained for at least 3-5 minutes.
2. Tourniquets
If direct pressure fails for an extremity wound, or if the bleeding is catastrophic and arterial from the start, apply a commercial tourniquet (e.g., CAT).
- Placement: "High and Tight" (over the clothing) during care under fire/immediate danger. Once in a secure area, place 2-3 inches above the wound on bare skin.
- Tightening: Twist the windlass until the bleeding STOPS and distal pulses are ABSENT.
- Documentation: Always write the time of application on the tourniquet and the patient's forehead.
3. Wound Packing
For junctional areas (groin, axilla, neck) where a tourniquet cannot be placed:
- Identify the bleeding source deep in the wound.
- Tightly pack hemostatic gauze (or standard gauze) directly against the bleeding artery.
- Apply very firm direct pressure over the packed wound for 3 minutes (if hemostatic) or 10 minutes (if standard gauze).
Recognizing Shock
Shock is inadequate tissue perfusion. Recognize the stages:
- Compensated Shock: Tachycardia, normal BP, delayed CRT, anxiety, pale/cool skin. The body is fighting to maintain blood pressure.
- Decompensated Shock: Hypotension (falling BP), altered mental status, absent peripheral pulses. The compensatory mechanisms have failed. Death is imminent.
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