Hand-Assisted Laparoscopic Abdominoperineal Resection

Walter J. Peters Jr

Winston M. T. Chan

INDICATIONS/CONTRAINDICATIONS

Advancements in surgical technique, improvements in neoadjuvant therapy, and a redefinition of what constitutes an adequate distal margin of resection have resulted in an increase in sphincter-sparing procedures for malignancies of the rectum. Despite these advances, there are still patients for whom an abdominoperineal resection (APR) is the most appropriate operation.

Several recent randomized trials of open versus laparoscopic proctectomy, performed by expert, highly motivated and credentialed surgeons, reported APR in 13-23% of patients with cancers within 12 cm of the anal verge and 10% of patients with tumors up to 15 cm above the anal verge. APR is appropriate for recurrent rectal or anal cancer, anorectal melanoma not amenable to local excision, and for the patient for whom a sphincter-sparing procedure is not appropriate because of the depth of invasion into the anal sphincter, severe comorbidities or functional issues such as incontinence or impaired physical mobility.

PREOPERATIVE PLANNING

Accurate staging of rectal cancer requires assessment by digital rectal examination, rigid proctoscopy to determine the exact distance of the tumor above the anal verge, and complete colonoscopy to identify synchronous lesions. Radiologic staging should include a magnetic resonance imaging (MRI) performed with a specific rectal cancer protocol to accurately stage the primary tumor and to evaluate the status of the circumferential radial margin. MRI has replaced transrectal ultrasound for staging of the primary tumor because of superior visualization of the circumferential resection margin (CRM) and nodes proximal to the primary tumor. Computed tomography scans of the chest, abdomen, and pelvis complete the staging for distant disease.

The results of the clinical staging should then be discussed by a multidisciplinary team (MDT) including specialists in medical oncology, radiation oncology, radiology, pathology, and surgeons specializing in proctectomy for cancer. Depending on the clinical stage and the radiologic assessment for threatened circumferential margins, neoadjuvant therapy may be appropriate. For the past two decades, neoadjuvant therapy has typically consisted of radiation given in doses of 4,500-5,040 cGy with concomitant 5-FU. Alternative approaches have recently been suggested and are currently undergoing clinic trials. These variations include neoadjuvant chemotherapy with FOLFOX and total neoadjuvant therapy. If the initial staging indicated a threatened margin that might require extending the surgical procedure beyond the usual planes of dissection, reimaging with MRI may be helpful in planning the resection. This fact is especially true in the case of an APR where the surgeon has the option of performing an extralevator abdominoperineal excision to obtain a negative margin. The timing of surgery will depend on the type of neoadjuvant therapy recommended by the MDT, but it is typically performed at least 8 weeks after completion of radiation therapy to allow time for tumor regression.

Assessment should also focus on identifying barriers to recovery that can be addressed preoperatively to improve the quality of recovery. These interventions may include nutritional support,
physical rehabilitation, smoking cessation, and planning for postdischarge care for patients unlikely to be able to be discharged to their home. Patient education should also begin during the preoperative planning phase to allay patient fears and to set expectations for the pace of recovery. For patients anticipated to require a colostomy, preoperative teaching has been shown to decrease anxiety and to allow patients to quickly become self-sufficient.

SURGERY

Hand-assisted laparoscopic (HAL) APR consists of two separate operations. The abdominal procedure consists of mobilization of the descending colon and rectum, proximal vascular ligation, lymphadenectomy via total mesorectal excision (TME) and creation of a permanent colostomy. The perineal procedure consists of excision of the perianal skin, anal canal, levator ani muscles, distal rectum, and, occasionally, the coccyx or distal sacrum. The two procedures may be performed synchronously by two surgical teams, including two surgeons experienced in rectal resections for cancer. The perineal dissection, which is vitally important to the oncologic outcome, should not be relegated to an inexperienced surgeon. The synchronous approach allows simultaneous dissection of the distal rectum from above and below, shortening operative times and allowing the two surgeons to assist each other in identifying the correct planes of dissection. The two stages may also be sequentially performed by a single surgical team. The abdominal procedure is traditionally performed first, but it is also possible to begin with the perineal dissection and proceed to the abdominal portion. If the stages are performed sequentially, the perineal procedure may be performed either in the lithotomy position or in the prone-jackknife position.

Positioning

The patient is positioned in low stirrups for the abdominal phase of the procedure. This position offers maximal flexibility by allowing the surgeon to stand between the legs, if necessary, for a difficult splenic flexure. It also allows access to the anus and vagina for the rare occasions when passage of a dilator or proctoscope facilitates identification of planes in a difficult, fibrotic pelvis. Care must be taken to avoid pressure at the lateral leg below the fibular head to avoid peroneal nerve injury. The hips should be nearly straight with flexion of no more than 10 degrees to avoid the thighs or stirrup padding interfering with the surgeon’s ability to operate in the upper abdomen. Ureteral catheters are utilized in selected cases, when the tumor abuts the ureter or in cases of recurrent cancer. The patient’s right arm must be tucked at the side to allow both the surgeon and camera operator to stand on the right side for isolation and division of the inferior mesenteric artery (IMA). The left arm may be placed on an arm board if preferred for vascular access or if the patient’s size makes tucking both arms difficult.

Many surgeons prefer to keep the patient in the lithotomy position for the perineal dissection, even if performing it sequentially rather than synchronously. This method avoids the need for repositioning the patient in mid-procedure and may shorten total operative time. The disadvantages of the low lithotomy position are significant and include ergonomic challenges for the surgeon and assistant because of the confined space between the patient’s thighs, difficulty maintaining a sterile field and limitations on the extent to which the incision can be made posteriorly in the event coccygectomy is required. Exposure and visibility may be worsened further if the patient shifts position while in steep Trendelenburg position during the abdominal portion of the procedure.

The advantages of the prone-jackknife position are significant. Both the surgeon and assistant have a clear view of the well-lighted operative field and can operate standing comfortably without the contortions necessary when the patient is in stirrups. There is no difficulty extending the incision posteriorly if coccygectomy or distal sacrectomy is required. It is much easier to maintain a sterile field; and wound closure can be done more precisely, which has decreased the incidence of perineal wound complications in our personal experience.

The patient is positioned prone with the anterior iliac spines supported on a gel roll and the buttocks retracted with wide strips of adhesive tape attached to the bed (Fig. 36-1). After closing the anus with a heavy, monofilament purse string suture, hair can be removed from the surrounding skin and a sterile prep and drape accomplished. This is a surgical field in which hair removal cannot be adequately performed until the patient is asleep and positioned on the operating table.

Traditionally, the abdominal procedure was performed first. Following abdominal closure and maturation of the colostomy, the patient was then turned to the prone-jackknife position. With the
recent renewed interest in a transanal approach to TME, we have found it useful to begin with the perineal dissection and dissect as far cephalad as possible. When the limits of dissection are reached, the closed anus and distal rectum are pushed cephalad, a Betadine-soaked sponge is placed in the deep pelvis, and the perineal wound is closed. The patient is then turned and placed in low stirrups, or occasionally supine, for the abdominal portion of the procedure. This approach offers the same potential advantages as suggested for a transanal TME with improved visualization of the distal rectum and levator ani (Figs. 36-2 and 36-3). It also allows the surgeon to address the most critical portion of the oncologic procedure early in the case rather than after mobilizing the descending colon, dividing the IMA and dissecting the proximal and mid rectum.

FIGURE 36-1 Positioning for the prone perineal dissection. The iliac crests are supported by a gel roll and chest rolls allow for chest expansion. The buttocks are retracted with tape. This patient had extensive perianal Paget’s disease with invasive adenocarcinoma in the low rectum and anal canal.

FIGURE 36-2 The sigmoid colon is seen through the completed anterior dissection. Note the glistening intact mesorectal fascia as the rectum has rotated as it retracted posteriorly and to the left. The right ovary is marked with an arrow.

Abdominal Technique

Trocar Placement

Placement of the hand-access incision and laparoscopic trocars should allow the surgeon to operate in all quadrants of the abdominal cavity. The ideal position for an individual case may vary depending on the surgeon’s dominant hand, the need for the surgeon to serve as a teaching assistant, or patient characteristics such as preexisting scars or ostomies. For most cases, it is the authors’ preference to place the hand port through a periumbilical incision in a patient of normal habitus.^¹ A 12-mm trocar is placed in the suprapubic position, approximately 2 cm above the pubic bone and 5-mm trocars are placed in the left and right mid-abdominal positions lateral to the rectus sheath. It is ideal to have approximately one handbreadth between the trocars and the hand-access device to allow a wide range of motion at each trocar without colliding with the hand port. The surgeon stands to the patient’s right side, placing the left hand through the hand port and operating through the suprapubic trocar. The table should be rolled toward the surgeon so that gravity will assist in retracting the small bowel toward the right side of the abdomen. It is important to keep the height of the table low enough that the surgeon can operate with the shoulders relaxed and the elbows at an angle greater than 90 degrees to reduce fatigue and lessen the risk of long-term injuries to the neck and shoulders.

FIGURE 36-3 Presacral fascia as seen from the perineal approach with the patient prone. The cut edge of the right levator is marked with arrows.

Transversus Abdominus Plane Block

If a transversus abdominus plane (TAP) block has not been preoperatively performed by the anesthesiologist, it is performed under direct laparoscopic guidance. The anesthetic agent(s) of choice may differ based on the formulary available at an institution. A mixture of bupivacaine 0.5%, 150 mg (30 ml) and liposomal bupivacaine, 266 mg (20 ml) will provide abdominal wall hypesthesia for up to 72 hours. A 5-mm 30-degree camera is placed in the left mid-abdominal trocar and a syringe with a 22-gauge needle is passed through the abdominal wall in the lateral right upper quadrant (RUQ) until it indents the peritoneum. It is then withdrawn slightly and approximately 5-10 ml of the anesthetic mixture is infiltrated into the plane between the transversus abdominus muscle and the internal oblique muscle. Correct placement of the anesthetic is noted by seeing a diffuse bulge in the abdominal wall with the transversus fibers being pushed toward the abdominal cavity. If the fibers separate or become obscured by a wheal forming beneath the peritoneum, the injection is too deep. If no bulge is noted, the injection is most likely too superficial. This process is repeated at three or four sites in the RUQ until 20 ml of the anesthetic solution has been infiltrated. The camera is then moved to the right mid-abdominal trocar and the process is repeated to place the block in the left upper quadrant. The remaining 10 ml of anesthetic can be reserved to infiltrate the perineal wound.

Exploration of the Abdomen

The camera is then moved back to the left mid-abdominal site and a visual exploration of the abdomen is performed. The omentum and parietal peritoneal surfaces can be inspected visually; and the left hand, placed through the access device, can palpate the bowel and abdominal wall. Careful attention must be paid to the surface of the liver. Small nodules that were not visible on preoperative imaging may be present on the surface of the liver. Liver lesions can be biopsied, if necessary, by passing a percutaneous biopsy needle through the upper abdominal wall or using a laparoscopic biopsy forceps to remove a capsular nodule. The surgeon’s intra-abdominal hand is used to provide maximal exposure of the liver surfaces as well as to palpate the parenchyma for deeper lesions. Any areas identified as abnormal on imaging should be examined before proceeding with resection.

Mobilization of the Left Colon

The quality of the end descending colostomy created during APR is a significant measure by which the patient will judge the operation as a success or as a failure. A properly constructed colostomy requires the end of the descending colon to reach the skin of the abdominal wall at the optimal site, as selected by the patient and wound ostomy care nurse (WOCN), with no tension. This requirement
mandates that at least the descending colon be mobilized and, in some patients, the entire splenic flexure must be mobilized. This mobilization may be performed in either a medial-to-lateral or lateral-to-medial manner. The lateral-to-medial approach is more familiar to surgeons trained initially in open colectomy. The medial-to-lateral approach offers immediate entry into the correct retrocolic plane, earlier identification of the left ureter, and early isolation of the IMA.

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