The double loop suture is run in a continuous manner taking full thickness of the linea alba fascia and peritoneum on either side of the incision (Figure 17). After placement of the final stitch superiorly, the needle is cut off and one limb of the suture retracted back across the incision. This allows the two cut ends to be tied along one side of the incision.
Some surgeons prefer to use the figure-of-eight, or so-called eight-pound stitch, when closing fascia with the interrupted sutures. A full-thickness horizontal bite is taken that enters the linea alba on the far side at A and exits at B (Figure 18). The suture is advanced for a centimeter or two, and an additional transverse full-thickness bite is taken that enters at C and exits at D. When the two ends of the suture are tied, a crisscrossing, horizontal figure-of-eight is created (Figure 19). The knot should be tied to one side. In general, the figure-of-eight suture is placed snugly rather than tightly where it may cut through the tissue with any postoperative swelling.
After each knot is tied during the closure, the ends of the suture are held under tension by the assistant and are cut. Silk sutures may be cut within 2 mm of the knot, whereas many absorbable or synthetic sutures require several millimeters be left, as the knots may slip. As the suture is held nearly perpendicular to the incision by the assistant, the scissors are slid down to the knot and rotated a quarter turn (Figures 20 and 21). Closure of the scissors at this level allows the suture to be cut near the knot without destroying it. In general, the scissors are only opened slightly such that the cutting occurs near the tips. Additional fine control of the scissors may be obtained by supporting the mid portion of the scissor on the outstretched index and middle fingers of the opposite hand just as the rest supports the chisel on a wood-turning lathe. Following closure of the fascia, some surgeons reapproximate Scarpa's fascia with a few interrupted 3/0 absorbable sutures (Figure 22), whereas others proceed directly to skin closure, the details of which are shown in Plate 8.
Occasionally, it is necessary to use a retention or through-and-through suture. This is especially true in debilitated patients who have risk factors for dehiscence such as advanced age, malnutrition, malignancy, or contaminated wounds. The most frequent use of retention sutures, however, is for a secondary reclosure of a postoperative evisceration or full-thickness disruption of the abdominal wall. Through-and-through #2 nonabsorbable sutures on very large needles may be placed through all layers of the abdominal wall as a simple suture or as a far-near/near-far stitch (Figure 27). In this technique, the fascia is grasped with Kocher clamps and a metal ribbon retractor is used to protect the viscera. The surgeon places the first suture full thickness through the far side abdominal wall. The needle is then brought through the near linea alba or fascia about 1 cm back from the cut edge with the path going from peritoneal surface toward the skin (Figure 23). The suture then crosses the midline to penetrate the far side fascia in a superficial to deep manner (Figure 24). The free intraperitoneal suture is then continued full thickness through the near abdominal wall (Figure 25). As seen in cross section (Figure 26), it is important that the abdominal wall full-thickness bites taken at the beginning and end of this placement are not positioned so laterally as to include the epigastric vessels within the rectus abdominis muscles. Compression of these vessels when the suture is tied may lead to abdominal wall necrosis. Additionally, the intraperitoneal exposure of this suture should be small so as to minimize the possibility of a loop of intestine becoming entrapped when the retention is tied. In general, the entrance and exit sites are approximately 1.5 or 2 inches back from the cut edge of the skin (Figure 27). Many surgeons use retention suture bolsters or simple 2-inch sections of sterilized red rubber tubing in order to minimize the cutting of the suture into the skin during the inevitable postoperative swelling. Because of this swelling, the retention sutures should be tied loosely rather than snugly such that the surgeon can still pass a finger between the retention suture and the skin of the abdominal wall.