How to drain a small skin abscess

There are several noticeable markers of a small, uncomplicated skin abscess:

1. Abscess is less than 5 cm in size.
2. Patient does not have a fever.
3. No surrounding cellulitis.
4. Patient is not immunocompromised (e.g., AIDS, chemotherapy, poorly controlled diabetes, immunotherapy-like transplant medicines, or chronic steroids).

Incision and drainage is the definitive treatment for soft tissue abscesses. Antibiotics alone cannot effectively penetrate the abscess, and may not work in the acidic environment within the abscess. As well, draining the abscess results in immediate pain relief by decreasing pressure on the skin’s nerve fibers.

There are four major scenarios where you should be careful about performing an incision and drainage:

1. Your patient has a prosthetic heart valve or other risk factors for developing endocarditis. In these cases, give the patient antibiotics before the procedure.
2. The abscess is near a vital structure (e.g., major blood vessel, nerve, or gland). In these cases, be careful about the depth of your incision. If you don’t feel comfortable, defer to a surgeon.
3. The abscess is located on a cosmetically significant area of the body (e.g., face or breast). In these cases, be careful about the size of your incision.
4. The abscess is large or deep. In these cases, you may need to take the procedure to the operating room.

Before you do an incision and drainage of an abscess, first collect the necessary medication and tools:

• Skin sterilizing solution
• 1% lidocaine with epinephrine
• 3 cc syringe and a 25 gauge (G) needle
• #11 scalpel
• Hemostat
• Gauze
• Tape

Now, let’s crack this abscess open! This step-by-step procedure ensures a safe, clean, and (relatively) painless abscess drainage:

1. Gently clean the skin with a sterilizing solution.
2. Apply ice to the abscess. Anesthetize the skin with lidocaine and epinephrine. The numb area will blanch within the next two minutes.
3. When the skin is numb (abscess appears blanched), make a 1–2 cm incision along the natural folds of the skin.
4. Apply gentle pressure around the abscess to get as much of the pus out as possible.
5. If the wound is deep, take the hemostat and gently probe the wound to break up loculations.
6. Take a culture of the wound if you anticipate poor wound healing (e.g., in an immunocompromised patient). Generally, most abscesses are caused by community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA).
7. Place a dressing, but do not pack the wound (packing the wound been shown to delay healing and cause more pain). There is also no need for irrigation of the abscess cavity.

The final decision to make is about antibiotics. In general, if it is an uncomplicated, small abscess, incision and drainage is the only treatment needed.

Before sending the patient home, give them some dressing supplies and ask them to the keep the abscess clean and dry by changing the dressing twice a day.

As well, instruct your patient to come back if they develop surrounding cellulitis, increasing pain, or fever. Either way, it’s a good idea to have them come back for a follow-up visit in two days.

That’s it for now. If you want to improve your understanding of key concepts in medicine, and improve your clinical skills, make sure to register for a free trial account, which will give you access to free videos and downloads. We’ll help you make the right decisions for yourself and your patients.