Surgical Site Infections
Your skin is a natural barrier against infection. Even with many precautions and protocols
to prevent infection in place, any surgery that causes a break in the skin can lead
to an infection. Doctors call these infections surgical site infections (SSIs) because
they occur on the part of the body where the surgery took place. If you have surgery,
the chances of developing an SSI are about 1% to 3%.
Types of surgical site infections
An SSI typically occurs within 30 days after surgery. The CDC describes 3 types of
surgical site infections:
Superficial incisional SSI. This infection occurs just in the area of the skin where
the incision was made.
Deep incisional SSI. This infection occurs beneath the incision area in muscle and
the tissues surrounding the muscles.
Organ or space SSI. This type of infection can be in any area of the body other than
skin, muscle, and surrounding tissue that was involved in the surgery. This includes
a body organ or a space between organs.
Signs and symptoms of surgical site infections
Any SSI may cause redness, delayed healing, fever, pain, tenderness, warmth, or swelling.
These are the other signs and symptoms for specific types of SSI:
A superficial incisional SSI may produce pus from the wound site. Samples of the pus
may be grown in a culture to find out the types of germs that are causing the infection.
A deep incisional SSI may also produce pus. The wound site may reopen on its own,
or a surgeon may reopen the wound and find pus inside the wound.
An organ or space SSI may show a discharge of pus coming from a drain placed through
the skin into a body space or organ. A collection of pus, called an abscess, is an
enclosed area of pus and disintegrating tissue surrounded by inflammation. An abscess
may be seen when the surgeon reopens the wound or by special X-ray studies.
Causes and risk factors of surgical site infections
Infections after surgery are caused by germs. The most common of these include the
bacteria Staphylococcus, Streptococcus, and Pseudomonas. Germs can infect a surgical wound through various forms of contact, such as from
the touch of a contaminated caregiver or surgical instrument, through germs in the
air, or through germs that are already on or in your body and then spread into the
The degree of risk for an SSI is linked to the type of surgical wound you have. Surgical
wounds can be classified in this way:
Clean wounds. These are not inflamed or contaminated and do not involve operating
on an internal organ.
Clean-contaminated wounds. These have no evidence of infection at the time of surgery,
but do involve operating on an internal organ.
Contaminated wounds. These involve operating on an internal organ with a spilling
of contents from the organ into the wound.
Dirty wounds. These are wounds in which a known infection is present at the time of
These are other risk factors for SSIs:
Having surgery that lasts more than 2 hours
Having other medical problems or diseases
Being an elderly adult
Having a weak immune system
Having emergency surgery
Having abdominal surgery
Helping prevent surgical site infections
If you are having surgery, ask your doctor what you can do to reduce your risk for
a surgical site infection. It's important to stop smoking before surgery and to tell
your surgical team about your medical history, especially if you have diabetes or
another chronic illness. Also, avoid shaving in the skin area that the surgeon is
planning to operate through.
No matter how curious they are, loved ones should not touch your wound or surgical
site. Carefully follow your doctor's instructions about wound care after surgery.
Call your doctor if you develop a fever or pus, redness, heat, pain or tenderness
near the wound or any other signs or symptoms of a surgical site infection.
Treating surgical site infections
Most SSIs can be treated with antibiotics. Sometimes additional surgery or procedures
may be required to treat the SSI. During recovery, make sure that friends and family
members wash their hands before and after they enter your room. Make sure doctors,
nurses, and other caregivers wash their hands, too.