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Procedure overview
Procedure overview
All equipment should be placed within reach, ideally on a Mayo stand. Adjust the lighting to allow easy visualization of the abscess.
Choose the incision site in the most fluctuant and prominent part of lesion, where the contents appear most liquefied, in order to permit rapid and effective drainage. In addition, consider starting with the most dependent portion of lesion for the ease of drainage utilizing gravity effect. The patient should be properly positioned so that the area for drainage is fully exposed and easily accessible, while ensuring the patientโs comfort.
Apply a topical antiseptic (alcohol, povidoneโiodine, or chlorhexidine) to the entire lesion and particularly to the area to be incised, followed by application of a sterile drape as indicated. Avoid using chlorhexidine in the ear and periorbital areas.1
An absorbent pad, gauze, or chuck is placed to protect other areas from draining exudate. Placement of a cotton ball or dental roll inside external ear canal is recommended to protect the ear from draining exudate. Gloves, gown, and a face shield should be worn at all times during the procedure to avoid exposure to bodily fluids, particularly from high-pressure abscesses.
Local anesthesia is injected into the selected incision site and around the lesion to minimize both the tenderness associated with pressure as well as the incision proper. This is achieved with infiltration of 1% to 2% lidocaine with or without epinephrine using a 30G needle. Care should be taken to deliver anesthetic solution into the skin overlying the lesion instead of infiltrating lidocaine into the cavity. Needle insertion is just under and parallel to the surface of the skin, and anesthetic is injected into the intradermal and subcutaneous tissues until blanching of the tissue is noted as the anesthetic diffuses. In patients with lidocaine allergy, alternatives can be employed. For a more detailed discussion of anesthetic choices, see Chapter 12.
Nerve block or local field block may be required for larger and deeper lesions to ensure the patientโs comfort. A ring block may permit anesthesia of the entire target area without directly injecting local anesthetic over the fluctuant mass, which may mitigate the risk of spray back. This approach, however, also does not infiltrate any epinephrine into the area to be incised, so an attendant increased risk of mild bleeding may be anticipated. Adequate anesthesia is essential for complete and thorough drainage. Depending on the patientโs pain threshold, ice cubes, ethyl chloride spray, or topical anesthesia may be helpful if applied prior to injecting lidocaine to decrease discomfort delivering local anesthesia. This is particularly important as the acidic environment of infected tissue may make it more difficult to achieve sufficient anesthesia with local agents.
When approaching small digital mucous cysts and trapped blood coagulum following sclerotherapy, I&D may be performed by rapid single puncturing with a needle, and local anesthesia may not be needed. Lidocaine injection may blanch the area or otherwise make these lesions more difficult to visualize for I&D. Ice cube, ethyl chloride spray, or topical anesthesia used instead of lidocaine injection may be better
for such lesions. Injectable lidocaine is necessary, however, when I&D of a digital mucous cyst is followed by destruction using electrodesiccation.