Upon entering the operating room, patients are positioned on a split-leg table, with the legs externally rotated and abducted, and the boundaries of the femoral triangle are mapped out with a surgical pen (Fig. 13.2). Accurate marking is necessary for both correct trocar placement and to aid in determining the extent of the dissection during the case. Clipping and prepping are performed via standard techniques. The suprapubic skin should be included in the sterile field so that development of crepitus can be monitored. Prior to starting the case, appropriate antibiotic prophylaxis is given. The surgeon is positioned between the patient’s leg, and the assistant stands to the outside of the operative limb (Fig. 13.3). The laparoscopic tower should be positioned on the side of the operative limb with the monitors placed at the patient’s shoulders.

A three-incision technique is used. The first is a 12-mm incision placed 3 cm distal to the apex of the femoral triangle. A scalpel is used to incise the skin and dissect down from Camper’s fascia to Scarpa’s fascia, although the precise delineation at this point is not critical, as this incision is outside of the boundaries of the template. Scarpa’s fascia, a glistening thin film, is then incised, and a finger is used to develop a space extending out 5 cm on each side of the incision (Fig. 13.4). This blunt finger dissection allows enough space to insert two additional 10-mm trocars to be placed under direct visualization. A 12-mm balloon port trocar is then placed in the original incision, and the dissected space is insufflated to 25 mmHg for 10 min. The pressure is then decreased to 15 mmHg to prevent end-tidal CO₂ elevation. Under direct visualization with a 0° 10-mm laparoscope, two 10-mm short bladeless trocars are inserted approximately a handsbreadth from the visualizing port. The trocars should be positioned 3 cm outside of the medial and lateral boundaries of the previously delineated femoral triangle.

At this stage, it is critical to ensure that the anterior working space is completely developed before proceeding with additional dissection. This anterior working space is defined as the area created between the fibrofatty packet containing the lymph nodes and the “flaps” that are created when dissecting along Scarpa’s fascia. The dissection should be extended superficial to Scarpa’s fascia. If the glistening undersurface layer of Scarpa’s fascia is identified, the flap is too thick and the plane must be changed. The correct tissue thickness is approximately 3–5 mm in most patients and allows the surgeon to see the cutaneous vessels when the skin flap is transilluminated with a camera. Loss of vessel visualization is often associated with flap necrosis of this area.

For melanoma patients with primary lesions of the trunk, dissection is routinely carried 5 cm above the inguinal ligament along the abdominal wall with an endoscopic dissecting stick in tandem with ultrasonic shears. Medial and lateral boundaries of the dissection consist of the adductor longus and sartorius muscle fascia, which should be correlated to the previous skin markings via transillumination. The fibrofatty packet may be rolled inward on both sides using an endoscopic sponge or Kittner. This maneuver is continued superiorly and inferiorly as much as possible to assist in defining the posterior tail of the node packet. Throughout the dissection, small perforating vessels are routinely encountered and should be controlled using an ultrasonic dissecting scalpel, LigaSure, or clips. Lymph vessels should be sealed with the ultrasonic dissecting scalpel. The deep thigh fascia (fascia lata) constitutes the posterior boundary, and its violation is readily apparent when reddish muscle fibers are encountered.

The saphenous vein is visualized within the apex of the femoral triangle and divided with the vascular load of an endoscopic linear cutting stapler. Careful dissection within the femoral triangle enables the identification of the femoral artery pulse. Laparoscopic ultrasound probes may be used to delineate the vessel anatomy if needed. The dissection is then carried from an inferior to superior direction on top of the artery. The femoral vein is identified using the artery as a landmark. Both vessels are then skeletonized, along with all of the tissue between the femoral vein and adductor longus. This dissection is more easily accomplished when the assistant elevates the packet, allowing the surgeon to work below it in the dissection plane.

Following completion of the vascular dissection, blunt dissection in the saphenofemoral junction is performed to identify the inferior edge of the saphenous vein. A right-angle dissector and a Hunter grasper are the preferred tools for this maneuver. An endoscopic linear cutting stapler with a vascular load is then used to transect the vein at this level (Fig. 13.5). While exposing the saphenofemoral junction , continued inferomedial dissection around the femoral vein will enable resection of the deep inguinal nodes. Dissection should be continued to the level of the femoral canal until the pectineus muscle is visible. This will ensure complete nodal retrieval and also provide exposure for a biopsy of Cloquet’s node, although this element has been largely abandoned in patients with only sentinel node involvement. Some fascial attachments to the inguinal ligament may remain at this point (Fig. 13.6). In order to completely separate the nodal packet from these attachments, the tissue must be dissected off the fascia by inferior retraction of the nodal packet. This technique will provide the appropriate visualization for blunt dissection or, in some cases, dissection of the tissue from the inguinal ligament using the ultrasonic dissecting scalpel.

Once the nodal packet is free, it is withdrawn in a laparoscopic specimen bag through the apical port. If the packet is too large, the extraction site may need to be extended. Direct visualization is used to confirm complete dissection of all lymphatic tissue. To complete the procedure, a 19-French fully fluted drain is placed through the lateral port site, and the skin is closed (Fig. 13.7). The patient is encouraged to ambulate on the day of surgery and given a regular diet. Discharge is routinely planned for the same day, unless concomitant pelvic node or deep pelvic node dissection is performed. The drain remains in place until the output is <30 mL/day.