A tunneling wound is a channel that extends from the main wound opening into deeper tissues, such as the subcutaneous layer or muscle. These narrow passageways form due to the destruction of underlying tissue, frequently caused by infection or pressure forces that create a path of least resistance beneath the skin surface. Accurate measurement of the tunnel’s depth and direction is a fundamental part of tracking the wound’s healing trajectory. A precise assessment allows for the selection of appropriate treatment protocols, particularly for selecting the correct packing material to fill the “dead space” and prevent abscess formation. Consistent measurement over time helps determine if the wound is progressing toward closure, indicated by a reduction in the tunnel’s length.
Preparing for Accurate Wound Assessment
Before beginning the measurement process, gathering the necessary supplies and establishing a clean environment ensures accuracy and prevents introducing bacteria into the wound. The essential tools include a sterile, flexible cotton-tipped applicator or a specialized wound probe, a disposable ruler marked in centimeters, and clean gloves. Hand hygiene must be performed thoroughly before donning the gloves to minimize the risk of contamination from the skin’s surface.
The environment should be set up to allow the procedure to be carried out with minimal interruption and maximum visibility of the wound area. The sterile probe must remain in its packaging until the moment of use to preserve its sterility. Using a fresh, sterile instrument for each measurement ensures that bacteria or debris is not transferred into the deeper wound channel.
Technique for Measuring Tunnel Depth
A tunneling wound measurement involves a gentle, systematic approach to map the channel without causing further trauma to the fragile tissue. Gently cleanse the main wound surface and surrounding skin with a prescribed solution to remove loose debris or excess exudate. This cleansing allows for a clear view of the wound margins and the small opening of the tunnel.
Next, the location of the tunnel opening relative to the main wound is identified and recorded using the clock-face method. This orientation places the patient’s head at the 12 o’clock position and their feet at the 6 o’clock position, allowing for the tunnel’s location to be described precisely, such as “tunnel at 4 o’clock”. The sterile probe is then gently inserted into the identified tunnel opening, following the direction of the tract.
The probe must be advanced only until a soft resistance is felt, indicating the end of the channel, and it must never be forced, as this could damage the tissue and create a false passage. Once the tip is at the end of the tunnel, the probe is grasped or marked at the point where it is level with the wound’s edge. Keeping a finger on the probe, the instrument is then carefully removed from the wound. The distance from the tip of the probe to the marked point is measured against the centimeter ruler. This distance represents the depth of the tunnel at that specific clock-face location.
Documenting Tunnel Location and Characteristics
The depth measurement obtained from the probe and ruler should be recorded in centimeters or millimeters, as this provides a standard unit for comparison over time. For instance, a record might note “tunnel depth 5.2 cm” at a specific clock position. The direction established during the measurement, such as the 7 o’clock position, must be explicitly documented alongside the depth. This documentation ensures that the exact channel is probed and remeasured consistently during subsequent assessments.
Beyond the dimensional data, any characteristics observed during the probing should be noted. These characteristics include the type and amount of exudate (e.g., serous, purulent), the presence of any odor, and the type of tissue felt at the end of the tract. Observing the tissue at the tunnel’s end, such as firm granulation tissue or non-viable slough, offers insight into the underlying healing environment. Consistent documentation at regular intervals provides the comparative data needed to assess the efficacy of the current treatment plan and determine if the tunnel is shortening.