A subcuticular suture is a specialized technique used in wound closure that places the suture material just beneath the skin’s outermost layer, the epidermis. This method aims to bring the wound edges together. It is often employed in situations where minimizing scarring is a significant concern.
Understanding Subcuticular Sutures
Subcuticular sutures are a preferred method for closing wounds, particularly in areas where cosmetic appearance is important, such as the face, neck, and abdomen. This technique minimizes visible scars by burying the suture material beneath the skin surface, preventing “railroad track” marks sometimes associated with traditional external sutures. This method also reduces the number of skin punctures, which can lower the risk of infection in clean surgical procedures.
This type of suture distributes tension evenly along the wound edges, promoting a smoother and more refined healing line. When absorbable suture materials are used, there is no need for a follow-up visit for suture removal. Subcuticular closures are effective for wounds under low tension, as they cause less trauma to the tissue.
Preparing for the Procedure
Beginning a subcuticular suture requires careful preparation, starting with the selection of appropriate instruments. A needle holder, also known as a needle driver, is used to grasp and manipulate the needle. Toothed forceps, or pickups, are employed to gently evert and stabilize the wound edges, while surgical scissors are needed to cut the suture material.
Choosing the correct suture material is also important for a successful subcuticular closure. Absorbable sutures, such as polyglactin 910 (Vicryl) or poliglecaprone 25 (Monocryl), are frequently preferred because they dissolve over time. Monofilament sutures, like Monocryl or polypropylene, are often favored over braided sutures due to their smooth surface, which reduces tissue drag and the likelihood of harboring bacteria. Suture sizes typically range from 5-0 to 6-0, especially for fine epidermal approximation.
Before starting the suturing, the patient and wound site must be properly prepared. This involves creating a sterile field around the wound to prevent infection, typically by cleansing the area with an antiseptic solution and draping it with sterile cloths. Local anesthesia is administered to numb the wound area. The wound itself is thoroughly cleaned and irrigated to remove any debris or contaminants, and any ragged edges are carefully debrided to create clean, well-defined wound margins.
Executing the Subcuticular Suture
The subcuticular suture technique begins at one end of the wound, often referred to as the apex. An initial bite is placed deep within the subcutaneous tissue to anchor the suture, burying the knot beneath the skin surface. The needle is typically inserted 2 to 5 mm from the wound’s apex, parallel to the incision line, and then passed directly through the epidermis to exit into the interior of the wound just medial to the apex.
Once the initial anchor is established, the needle is re-grasped with the needle holder, and the wound edge is gently everted using forceps. The needle is then inserted into the dermis on one side of the wound, with its trajectory running parallel to the incision line. The goal is for the needle to pass through the dermis at a uniform depth, approximately 1 to 2 mm deep to the skin surface, and exit at a point equidistant from the cut edge from where it entered.
After the needle exits the dermis, it is released and grasped with forceps, allowing the needle holder to be repositioned. The process is then repeated on the contralateral side of the wound, ensuring that the needle entry point is adjacent to or slightly proximal to the previous exit point. This creates a continuous suture pattern beneath the skin. Each subsequent bite should be of similar size and depth, typically 5 to 10 mm in length, maintaining a consistent plane parallel to the skin surface.
Maintaining proper tension throughout the suturing process is important to avoid puckering or excessive tightening of the skin. The suture should be pulled taut enough to approximate the wound edges without causing undue tension or blanching of the surrounding tissue. Some techniques involve introducing a small degree of backtracking with the needle to reduce the risk of tissue bunching as the suture progresses along the wound. The suture passes should remain perpendicular to the laceration, preventing the skin from being pulled at an angle.
As the suturing approaches the end of the wound, once the final bite is taken, the needle is inserted from the interior of the wound, in line with the incision, and exits just lateral to the apex of the wound. For absorbable sutures, the final knot is often buried. This involves passing the needle from superficial to deep at the apex, pulling the suture through to create a loop, and then tying a secure knot.
Achieving Optimal Results and Care
Optimal results with a subcuticular suture involve careful attention to wound approximation and post-procedure care. The goal is to align the skin edges precisely. If the subcuticular technique is used alone for skin surface approximation, applying skin tape or fine surface sutures can help correct any unevenness and provide more accurate epidermal apposition.
For absorbable sutures, the knot is typically buried beneath the skin. After the final pass, a loop of suture is created, which is then used to tie a secure knot. This knot should be pulled down into the deeper tissue, ensuring it lies flat and does not protrude, which could otherwise lead to irritation or erosion through the skin. For non-absorbable sutures, the ends are usually left exposed for later removal, or a specialized technique might be used to bury them.
Post-procedure wound care is important for preventing complications and promoting healing. A pressure dressing may be applied immediately after closure and should remain dry for at least 48 hours to minimize bleeding, swelling, and pain. After this initial period, the dressing can be carefully removed, often by soaking it to loosen adhesive, and the wound site should be gently cleaned with mild soap and water. Plain petrolatum ointment should be applied daily to keep the wound moist and prevent scabbing.
Patients should avoid strenuous activities, heavy lifting, or any movements that could place tension on the incision for at least one to two weeks, depending on the wound’s location. Patients should also avoid submerging the wound in baths, hot tubs, or pools. Patients should monitor the wound for signs of infection, such as increased pain, swelling, redness, pus, or fever, and seek medical attention if these symptoms appear. Absorbable sutures typically dissolve over several weeks, with Monocryl losing strength within approximately three weeks and fully absorbing within eight weeks, while Vicryl absorbs within six to eight weeks.