• Draw the shape and describe it.
• Measure the head-to-toe length, side-to-side width, and depth—use the greatest measurement for length, width, and depth (Taylor et al., 2023).

• Perform hand hygiene. Put on gloves.
• Moisten a sterile, flexible cotton-tipped applicator with saline and insert it gently into the wound at a 90-degree angle, with the tip down (Figure A).
• Mark the point on the swab that is even with the surrounding skin surface or grasp the applicator with the thumb and forefinger at the point corresponding to the wound's margin (Figure B).
• Remove the swab and measure the depth with a ruler (Figure C).

• Perform hand hygiene. Put on gloves.
• Determine direction: Moisten a sterile, flexible cotton-tipped applicator with saline and gently insert a sterile applicator into the site where tunneling occurs. View the direction of the applicator as if it were the hand of a clock (Figure D). The direction of the patient's head represents 12 o'clock. Moving in a clockwise direction, document the deepest sites where the wound tunnels.
• Determine the depth: While the applicator is inserted into the tunneling, mark the point on the swab that is even with the wound's edge, or grasp the applicator with the thumb and forefinger at the point corresponding to the wound's margin. Remove the swab and measure the depth with a ruler (see Figure C).
• Document both the direction and depth of tunneling.

Source: Adapted from Baranoski, S., & Ayello, E. A. (2020). Wound care essentials: Practice principles (5th ed.). Wolters Kluwer.