Backing out subcuticular suture
Video 4-07. Backing out running subcuticular suture
This is an epidermal approximation technique suitable for wounds under minimal to no tension in areas with an excellent vascular supply. This technique should almost never be employed in the absence of a deep dermal suture, since its strength is in fine-tuning epidermal approximation and it is ineffective in the presence of significant tension.
As with any technique, it is best to utilize the thinnest suture possible for any given anatomic location. Since the backing out subcuticular suture technique is not designed to hold tension, and its utility is limited to fine-tuning epidermal approximation, 5-0 or 6-0 suture is generally adequate when adopting this technique. This is especially important since a large volume of suture material is left in situ when utilizing this approach. It is best to utilize a monofilament suture material to minimize the coefficient of friction at the time of suture removal.
The needle is inserted at the far right corner of the wound, parallel to the incision line, beginning approximately 2-5 mm from the apex. The needle is passed from this point, which is lateral to the incision apex, directly through the epidermis, exiting into the interior of the wound just medial to the apex.
With the tail of the suture material resting lateral to the incision apex and outside the wound, the wound edge is gently reflected back and the needle is inserted into the dermis on the far edge of the wound with a trajectory running parallel to the incision line. The needle, and therefore the suture, should pass through the dermis at a uniform depth. Bite size is dependent on needle size, though in order to minimize the risk of necrosis it may be prudent to restrict the size of each bite. The needle should exit the dermis at a point equidistant from the cut edge from where it entered.
The needle is then grasped with the surgical pickups and simultaneously released by the hand holding the needle driver. As the needle is freed from the tissue with the pickups, the needle is grasped again by the needle driver in an appropriate position to repeat the earlier mentioned step on the contralateral edge of the incised wound edge.
A small amount of suture material is pulled through and the needle is inserted into the dermis on the contralateral side of the incised wound edge and the same movement is repeated. The needle should enter slightly proximal (relative to the wound apex where the suture line began) to the exit point, thus introducing a small degree of backtracking to the snake-like flow of the suture material.
The same technique is repeated on the ...