Wound closure in the emergency department can reduce the risk of infection, provide for improved cosmetic outcome, and maintain the skin's protective functions. Methods for wound repair include primary closure (immediately after injury), secondary closure (allowing a wound to heal on its own, which may be useful for contaminated or infected wounds), and delayed closure (packing the wound and performing closure at a later date once infection is ruled out).
Clinicians should consider several factors when choosing a wound closure method: time since injury, wound tension, whether tension is static or dynamic, and risk of scar formation. The cosmetic outcome after wound closure is primarily a function of technique and not necessarily reflective of the specific closure method or device that is selected. Options for closure include sutures, staples, adhesive tape, tissue adhesives, and hair apposition.
Sutures are strong, reliable, and adaptable and allow good approximation of wounds that are under tension. Absorbable suture material loses its tensile strength in <60 days and thus does not require removal after healing. Nonabsorbable sutures maintain their tensile strength and will require removal after a suitable time period for tissue healing. For most emergency department applications, either choice is acceptable as both have similar rates of infection, cosmetic outcomes, and wound dehiscence risks. Absorbable sutures are suitable for deep tissue structures such as dermis and fascia or when avoiding the need for suture removal is desired. Often, monofilament nonabsorbable sutures are used due to ease of use, good tensile strength, and low rates of infection. Suture material is available in a wide variety of sizes, with higher gauge sizes (such as 5-0 and 6-0) being very thin with less tensile strength. Smaller gauge sizes (such as 3-0 and 4-0) are larger in diameter with greater strength. Large gauge (e.g., 6-0) is most often chosen for areas of low tension where minimizing scars is desired, such as on the face. Smaller gauge suture (e.g., 3-0) is often used for the scalp, extremities, or other areas where increased tension requires suture material with greater tensile strength. When placing sutures of any size, be sure to evert the skin edges and avoid applying excessive crushing force on the tissue that can further damage the area and impair healing. Direct pressure, topical vasoconstrictors, or local anesthetic with vasoconstrictor are all useful for achieving hemostasis when repairing a wound.
Simple Interrupted Percutaneous Sutures
Placing simple interrupted sutures is the easiest and most commonly used technique for wound repair. The needle is introduced on one side of the wound, through the deep tissues, and exits the other side of the wound (Fig. 10-1). Be sure to keep the needle tip at 90 degrees to the skin and evert the wound edges for best results, and take care not to pucker the skin when tying the knot. Square knots are generally tied with the number of knots corresponding to the suture gauge (e.g.,four knots when using 4-0 suture material). Position the knots so that they all remain on the same side of the wound.
Placement of simple interrupted sutures. (A) Enter at 90 degrees. (B–D) Exit the same distance as the entrance. (E–G) Be consistent and tie knots on one side of wound.
Reproduced with permission from Reichman EF: Emergency Medicine Procedures
. 2nd ed. New York: McGraw-Hill Education; 2013.
Continuous (Running) Percutaneous Sutures
A rapid method for closure of high-tension wounds, this method can be challenging to get cosmetically optimal results in irregularly shaped wounds and thus is most appropriate for long linear lacerations. Place a suture at one end of the wound, tie, but do not cut the suture material. Then sew back and forth down the wound at a 65 degree angle until the opposite end is reached, at which point the suture material is tied off and cut (Fig. 10-2).
Continuous running. (A–C) Begin like a simple interrupted. (D–F) Be consistent, use a 65 degree angle. (G–I) Tie off at the end.