How To Incise and Drain an Abscess

ByMatthew J. Streitz, MD, San Antonio Uniformed Services Health Education Consortium
Reviewed/Revised Apr 2023
View Patient Education

A soft-tissue abscess may need to be incised and drained.

A soft-tissue abscess is typically a palpable, tender, red lump containing pus. There is usually localized induration and some "give" with palpation as opposed to the solid feeling of a mass or nodule. (See also Abscesses.)

Indications for Incising and Draining an Abscess

  • Soft-tissue abscess

For small and/or superficial abscesses, treat initially with heat and oral antibiotics and reevaluate need for drainage after 24 to 48 hours.

Contraindications to Incising and Draining an Abscess

Absolute contraindications

  • None

Relative contraindications

  • Certain abscesses may require drainage in an operating room.

  • Uncertainty whether lesion represents focal cellulitis with induration and swelling or an actual abscess (ultrasonography may be helpful)

Consider operating room management for

  • Abscesses close to major neurovascular structures (eg, the axilla, antecubital fossa, posterior knee, groin area, neck)

  • Infections of the hand other than those limited to the distal finger (because of complicated anatomy and small areas)

  • Facial infections (because adequate anesthesia is difficult and the cavernous venous sinus is nearby for facial abscesses above the upper lip and below the brow)

  • Large or deep abscesses (alternatively, experienced practitioners with available technology may consider doing ultrasound or CT-guided percutaneous needle aspiration)

Complications of Incising and Draining an Abscess

  • Bacteremia and sepsis

  • Chronic draining sinuses and fistulas, secondary to inadequate drainage of deep or complicated abscesses

Equipment for Incising and Draining an Abscess

  • 21- and 25-gauge needles

  • 10-mL syringe

  • Irrigation syringe

  • Hemostat or small forceps

  • #11 scalpel

  • Culture swab

  • Packing material, such as ½- to 1-cm sterile gauze strip

  • Absorptive bulk dressing (such as 4 × 4 gauze squares and tape; circular dry gauze wrap on extremities)

  • Nonsterile gloves

Additional Considerations for Incising and Draining an Abscess

Preincision antibiotics: For patients at high risk of infectious endocarditis complications

Less invasive alternatives: Avoid aggressive incision in abscesses in cosmetic areas, in areas under significant skin tension (eg, extensor surfaces), and in areas with extensive scar tissue (eg, sites of multiple previous drainage procedures). Instead, use a stab incision or needle aspiration to limit tissue injury and resultant scar formation. Multiple needle aspirations, ultrasound-guided needle aspiration, or delayed incision and drainage may be required. The abscess should be reassessed every 1 to 2 days to determine whether additional intervention is needed.

Relevant Anatomy for Incising and Draining an Abscess

  • Varies by location

Positioning for Incising and Draining an Abscess

  • Patient comfort with excellent exposure of abscess

Step-by-Step Description of Incising and Draining an Abscess

  • If available, point-of-care ultrasound may be used to identify extent of abscess and possible loculations.

  • Inject local anesthetic using a 25-gauge needle either along the line of incision over the dome of the abscess, or, more effectively, as a field block around the entire abscess; in some locations, a nerve block also can be used.

  • If injecting along the incision, be careful not to inject into the abscess cavity, which is painful and fails to numb the skin.

  • To create a field block, inject local anesthetic in a diamond-shaped pattern around the entire abscess. Start at one of the apices of the diamond and inject for the length of the needle, then reinsert it through anesthetized skin as you continue around the abscess.

  • Make a linear incision over the full length of the abscess using a #11 scalpel, following skin creases if possible.

  • Gently squeeze the wound to express the pus.

  • Culture of the abscess is not routinely necessary but may be done in patients who have systemic symptoms and signs, severe local infection (cellulitis), recurrent abscesses, or failure of initial antibiotic treatment and in patients at the extremes of age or who are immunocompromised.

  • Sweep a hemostat or forceps around the abscess cavity to break up loculations. Consider using a blunt-ended, rigid suction device to extract pus from large or deep abscesses, which also assists in breaking up loculations.

  • Correct predisposing conditions, such as obstruction of natural drainage (eg, due to redundant skin folds) or the presence of a foreign body.

  • If it is difficult to completely evacuate the abscess contents, irrigate the cavity with normal saline solution.

  • Although packing was commonly done in the past, it is not considered necessary except for pilonidal abscesses > 5 cm and, possibly, abscesses in immunocompromised patients and those with diabetes.

  • Place an absorbent gauze pad over the wound. If on an extremity, secure the pad with circular dry gauze wrap. Splint the affected part if possible, particularly if a joint is affected.

Aftercare for Incising and Draining an Abscess

  • Reevaluate and redress the wound in 24 to 48 hours. Exceptions are some small abscesses, such as paronychias or small furuncles, which do not need to be monitored as closely.

  • Drainage relieves most of the pain of an abscess, but postoperative analgesics may be required.

  • Instruct the patient to elevate the wound and not disturb the dressing and splint before the first follow-up visit.

  • Any packing may be removed once there is healthy granulation tissue throughout the cavity and there is no longer any drainage. Have the patient begin warm soaks and gentle hydrostatic debridement at home (ask the patient to hold the skin incision open and direct the shower or faucet spray into the abscess cavity). Continue dressing changes every 1 to 2 days and follow-up visits as needed until fully healed.

  • Patients should be reevaluated if they have worsening pain, increased drainage, or spreading erythema.

Antibiotics

Prescribe empiric antibiotic therapy after drainage with a drug active against methicillin-resistant Staphyloccocal aureus (MRSA) and beta-hemolytic streptococci in patients who have the following:

  • Significant associated cellulitis or septic thrombophlebitis

  • A deep abscess

  • Multiple or recurrent abscesses

  • Systemic symptoms and signs

  • Immunocompromise

  • A facial abscess above the upper lip and below the brow

  • High-risk heart disease, particularly with severe or extensive disease, comorbid conditions, extremes of age, or an abscess on the face, a hand, or the genitals

Patients should receive antibiotics for at least 5 to 7 days after the procedure. Consider admission for anyone immunocompromised with systemic symptoms (eg fever, chills) or anyone with signs of sepsis.

A common practice is to give an initial IV dose of antibiotic in the emergency department, followed by oral antibiotics.

Warnings and Common Errors When Incising and Draining an Abscess

  • Do not underestimate the need for analgesia. Inadequate analgesia deters thorough wound care.

  • The skin of a pointing abscess is very thin, making it difficult to inject local anesthetic into the skin rather than the abscess cavity; use a field block instead.

  • Without proper incision and drainage, spontaneous rupture and drainage may occur, sometimes leading to the formation of chronic draining sinuses. Incomplete resorption may leave a cystic loculation within a fibrous wall that may become calcified.

  • Perirectal abscesses have a high morbidity and mortality if incision and drainage are incomplete and should be evaluated by a surgeon. Patients with large and deep abscesses should be admitted to the hospital for evaluation and treatment under general or spinal anesthesia.

  • A facial abscess above the upper lip and below the brow may drain into the cavernous sinus, so manipulation of an abscess in this area may predispose to septic thrombophlebitis. After incision and drainage, treat with antistaphylococcal antibiotics and warm soaks and have frequent follow-up visits.

Tips and Tricks for Incising and Draining an Abscess

  • When doing a field block, after the first injection always reinsert the needle through anesthetized skin to minimize the number of painful pricks.

  • For breast abscesses, ultrasound-guided needle aspiration, as opposed to formal incision and drainage, is becoming the standard of care.

  • Sebaceous cyst abscesses have a pearly white capsule. The capsule must be removed for complete healing either at the time of abscess drainage or at a follow-up visit once inflammation has resolved.

  • For paronychia, consider simply lifting the eponychial fold away from the nail matrix to allow the pus to drain; after this, adequate drainage is likely.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  1. Johnson EK. Voel JD, Cowan ML, et al : The American Society of Colon and Rectal Surgeons' clinical practice guidelines for the management of pilonidal disease. Dis Colon Rectum 62:146-157, 2019. doi: 10.1097/DCR.0000000000001237

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