When severe bleeding leads to large amounts of blood loss, it can quickly become fatal. Both internal and external bleeding can be life-threatening, depending on the volume lost. Nursing students often ask, “How much blood can a person lose before it’s too much?” or “What’s the difference between arterial and venous bleeding?” Understanding these fundamentals is crucial for future nurses, and in a First Aid course, you’ll gain practical skills to manage these emergencies.
Blood Volume and Deadly Bleeding
On average, a human body contains about 5 to 6 liters of blood. While factors like age, size, and athleticism play a role, even a loss of around 500 mL (about two cups) can become life-threatening. External deadly bleeding is visible and easier to address, while internal bleeding – blood trapped under the skin – requires immediate medical attention. In this guide, we’ll focus on external bleeding and life-saving techniques to control it.
Types of External Bleeding: Arterial vs. Venous
External bleeding falls into two types:
Arterial Bleeding: From the artery, high-pressure and often spurting or spraying.
Venous Bleeding: From the vein, lower pressure, with a steady flow.
Knowing the type of bleeding helps determine the approach to control it effectively.
The 3 P’s to STOP External Bleeding
Pressure Direct "Place direct pressure on the wound"
Pressure Bandages "Place a pressure bandage to maintain even pressure "Avoid cutting off circulation".
Pressure Points "Place pressure in the joint directly above the wound to slow the blood flow, Avoid cutting off circulation"
Applying the right type of pressure can significantly reduce blood loss without the risks associated with using a tourniquet. Avoid tourniquets unless professionally trained, as they cut off blood flow completely, which can lead to complications. Instead, these “3 P’s” are effective tools for “slowing the blood flow” so the body can form clots and stop bleeding.
Steps to Control External Bleeding
Ensure Safety: Check for your own safety before approaching the victim.
Call 911: For high-volume bleeding or if you’re unsure of the situation.
Expose and Rinse the Wound: If necessary, rinse with clean water.
Apply Direct Pressure: Press a bandage directly on the wound to slow blood flow. Avoid removing blood-soaked bandages; instead, add more on top.
Use a Pressure Bandage: Wrap with moderate pressure using gauze or a triangular bandage. Check circulation by pressing on the skin beyond the wound; color should return quickly.
Apply Pressure Points: For serious bleeding, place a rolled bandage in a joint (like the armpit or groin) above the wound and have the person bend the joint to press against the roll. This slows blood flow above the injury.
Combine All 3 Techniques: Direct Pressure, Pressure Bandage, and Pressure Points together increase survival rates in cases of severe bleeding.
If possible, elevating the limb and applying a cool pack may further reduce blood flow.
Preparation and training make all the difference in emergencies. Learning these skills in a First Aid course provides nursing students with the knowledge needed to act confidently and save lives.
Learn these life-saving techniques with Saving Grace Medical Academy Ltd., where our First Aid courses for nursing students provide essential skills for managing severe bleeding and other critical emergencies.
Disclaimer: This information is provided for educational purposes based on materials from the Canadian Red Cross, Heart & Stroke Foundation, and Alberta Health Services. For detailed guidance, consult a certified First Aid instructor or physician.
RESOURCES:
Author - Saving Grace Medical Academy Ltd
Jason T
Retired EMT - Heart & Stroke Foundation Senior Instructor