Capillary Bleeding

Video 27 of 61
4 min 31 sec
English, Español
English, Español

While you're probably familiar with veins and arteries, capillaries may warrant a quick definition. Capillaries are tiny blood vessels linking arteries and veins that transfer oxygen and other nutrients from the blood to all body cells and remove waste products.

Generally speaking, there are three types of bleeding. Arterial is the worst of the three and the hardest to control, as it's under pressure and gushes. Then there's venous bleeding – those wounds drip and ooze and are under negative pressure. And then there's capillary bleeding.

Capillary bleeding has the classic appearance of a road rash type of wound. Anyone who has fallen off a bike or while playing sports likely has some experience with this type of bleeding injury.

Capillary bleeding distinctions are:

  • The blood tends to ooze or bubble up on the surface of the wound
  • The pressure is very low and will usually clot on its own or with minimal direct pressure
  • The blood is mixed with serous fluid

Serous fluid is a yellowish liquid that is made up of proteins and water. It's the same fluid that fills a burn blister and is the body's attempt to heal the wound.

How to Provide Care

Don't get too distracted by the obvious abrasive wound which isn't probably life-threatening. Instead, think about other areas and possible injuries that may require care and may even be life-threatening, such as:

  • Head wounds, concussions
  • Neck or spinal injuries
  • Fractures

Ask the victim if they're hurt anywhere else, and if they're experiencing any other pain. Once you've established that you're only dealing with an abrasion, treat it using the steps below.

As always, the first thing you want to do is make sure the scene is safe and that your gloves are on. (If you don't have gloves, wash your hands or use an alcohol-based hand sanitizer.) Make sure you have your rescue mask with a one-way valve handy and introduce yourself to the victim.

  • Find the source of the bleeding. You may have to remove or cut away clothing to reveal the wound.
  • Clean the wound using clean, potable water. Pour or run water over the abrasion while brushing off blood and debris – dirt, loose pebbles, etc.

Pro Tip #1: While capillary bleeding wounds tend not to be as serious as arterial or venous, the pain is usually more severe. If you encounter embedded debris in the wound, save it for medical personnel who can numb the area before removing those objects.

  • Dab the wound with (ideally) a sterile pad or bandage. However, anything clean will work, like napkins or tissue.
  • Once the wound is clean and dry and the bleeding has stopped, apply an antibacterial cream (if you have one) to stop any chance of infection.
  • Apply a bandage large enough to cover the entire wound. A standard size band aid isn't going to cut it. If you have a first aid kit, check for a 3”x4” sterile dressing pad. Then put the antibacterial cream directly on the pad, then apply that side to the victim's abrasion.

Pro Tip #2: While a bandage would be nice, it's not really necessary. (The antibacterial cream is far more important.) Just make sure the victim is careful with the wound while in transport to a place where a bandage can be applied.

  • To hold the bandage in place, fix two pieces of medical tape (from the first aid kit you hopefully have), one to the top of the dressing bandage and one to the bottom. Ask the victim to hold the bandage in place while you tape it over their wound.

Remember, even though capillary bleeding injuries aren't usually serious, it's always important to monitor the victim for signs of shock – pale, cool, sweaty, trouble breathing, etc. Shock can escalate a situation very quickly; better to catch it early and activate EMS immediately if you do.

A Few Common Capillary Bleeding Questions

Can I clean the wound using hydrogen peroxide?

While you may have heard about using hydrogen peroxide for wound cleaning, the medical community is steering rescuers away from this practice, as peroxide is a little too harsh on body tissue.

Instead, clean the wound using clean, potable water. It's a much better option.

Why are capillary bleeding wounds usually more painful than arterial or venous bleeding wounds?

Capillary bleeding injuries affect the epidural layer where the nerve endings are located, which is why they can be more painful than other types of bleeding injuries.

What's the biggest area of concern with capillary bleeding injuries?

With arterial and venous bleeding injuries, controlling bleeding is the chief concern. However, with capillary bleeding injuries, reducing the chance of infection is BY FAR the greatest area of concern.

Remember, these injuries usually involve a collision between a large surface area of the body and an external surface area that's likely far less than sterile, leaving some of that unsterile surface inside the fresh wound.