RECONSTRUCTIVE Robotic, Intraperitoneal Harvest of the Rectus Abdominis Muscle John Pedersen, M.D. David H. Song, M.D., M.B.A. Jesse C. Selber, M.D., M.P.H. Houston, Texas; Chicago, Ill.; and Akron, Ohio
Background: The rectus abdominis muscle is a workhorse for free and pedicled muscle coverage. Traditional harvest violates the anterior rectus sheath and requires an abdominal incision. Robotic harvest can be reliably and efficiently performed using three ports and no additional incisions. Methods: Ten robotic rectus muscle harvests were performed at three institutions as free flaps for extremity coverage and pedicled flaps for minimally invasive pelvic surgery requiring soft-tissue reconstruction. Three contralateral ports and an intraperitoneal approach were used in each harvest. Demographic information, operative variables, and outcomes were recorded. Results: All cases were completed robotically by three surgeons at three different institutions. Four muscles were harvested as free flaps for lower extremity and six muscles were used as pedicled flaps, three for abdominopelvic defect reconstruction and two for protection of visceral repair following salvage prostatectomy or anterior pelvic exenteration. Average robotic setup time was 15 minutes. Average robotic harvest time was 45 minutes. Two 8-mm ports and one 12-mm port were used in each case. One patient developed a grade I decubitus ulcer during an extended operation. There were no other complications. All muscles were completely viable following harvest. There were no conversions to open technique, and no hernias or bulges were noted. Conclusions: Robotic rectus muscle harvest is safe, efficient, and reproducible. The anterior rectus sheath can be left completely intact, eliminating incisional morbidity. The cumulative incisional length can be less than 2 inches even for extensive, multiservice pelvic procedures. (Plast. Reconstr. Surg. 134: 1057, 2014.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.
he rectus abdominis muscle flap is among the most frequently used flap for both free and pedicled reconstruction.1–5 Its axial, type III blood supply and long, large-caliber pedicle make it ideal for a multitude of indications. A variety of incisions have been used to harvest the rectus muscle, including midline, paramedian, and Pfannenstiel incisions. The principal disadvantage of these approaches is an incision on the abdomen, which is both unattractive and violates the anterior rectus sheath.6–9 From the Department of Plastic Surgery, The University of Texas M. D. Anderson Cancer Center; the Section of Plastic and Reconstructive Surgery, University of Chicago Medicine; and Akron General Medical Center. Received for publication February 13, 2014; accepted March 27, 2014. Presented in part at the 2011 American Society of Reconstructive Microsurgery Annual Meeting, in Cancun, Mexico, January 15 through 18, 2011. Copyright © 2014 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000000586
Intraperitoneal harvest of the rectus muscle using minimally invasive techniques has theoretical advantages. First, it is performed entirely through ports placed laterally on the contralateral abdominal wall (along the medial edge of the external oblique), eliminating any violation of the anterior rectus sheath. The intraperitoneal approach allows the muscle to be harvested on the inside, with the access through the posterior sheath, which provides, very little structural integrity to the abdominal wall, Disclosure: The authors have no financial interest to declare in relation to the content of this article. Supplemental digital content is available for this article. Direct URL citations appear in the text; simply type the URL address into any Web browser to access this content. Clickable links to the material are provided in the HTML text of this article on the Journal’s Web site (www. PRSJournal.com).
Plastic and Reconstructive Surgery • November 2014 and leaves the anterior sheath overlying the empty rectus sheath completely intact. In addition, using a “port-only” technique, incisional length can be limited to the cumulative length of the three ports (approximately 2 inches) (Fig. 1). Robotic harvest makes the intraperitoneal approach not only possible but simple. This is because the platform is extremely precise, with 100 percent tremor elimination and up to 5:1 motion scaling, and comes equipped with highresolution, three-dimensional optics, permitting extremely precise dissection of vascular structures with a low risk of injury. In addition, the robotic arms, because of their inherent stability and flexibility, are not limited by position restrictions that can thwart a laparoscopic approach. Specifically, the instruments are inserted laterally and have to be aimed “upward,” toward the midline to perform the dissection, a position that is awkward for human arms and laparoscopic instruments. The robotic, intraperitoneal approach was developed in the cadaver laboratory in 2009, and was first performed clinically in 2010.10 Subsequent cases have been performed at three different institutions. The purpose of the present work
Fig. 1. Robotic harvest of the rectus abdominis muscle is through an intraperitoneal approach. This allows the muscle to be harvested on the inside, with the access through the posterior sheath, which provides very little structural integrity to the abdominal wall, and leaves the anterior sheath overlying the empty rectus sheath completely intact. In addition, using a port-only technique, incisional length can be limited to the cumulative length of the three ports (approximately 2 inches). A well-healed donor site is shown here.
is to describe the technique, indications, and early outcomes with this procedure.
PATIENTS AND METHODS Ten robotic rectus muscle harvests were performed at three institutions as free flaps for extremity coverage and pedicled flaps for minimally invasive pelvic surgery requiring soft-tissue reconstruction. Three contralateral ports and an intraperitoneal harvest approach were used in each case. In half the free flap cases, a small pubic hairline incision was used to remove the muscle. In the other half, the muscle was removed with a laparoscopic retrieval sac (Anchor Products, Addison, Ill.) through one of the ports. In the pedicled flap cases, ports were used for harvest and inset of the flap for either abdominopelvic resection defects or to protect rectal repairs following prostate surgery with rectal involvement. Surgical Technique Markings and Port Placement The contralateral costal margin and iliac crest are marked along a line connecting the anterior axillary line and the anterior superior iliac spine. The midpoint between these two landmarks and 2 cm lateral to it is the desired location of the 12-mm camera port. On either side of the camera port, approximately three fingerbreadths away, or 1 to 2 cm from the costal margin and iliac crest, respectively, is the planned location of the two 8-mm instrument ports (Fig. 2).
Fig. 2. Markings and port placement. The contralateral costal margin and iliac crest are marked along a line connecting the anterior axillary line and the anterior superior iliac spine. The midpoint between these two landmarks and 2 cm lateral to it is the desired location of the 12-mm camera port. On either side of the camera port, approximately three fingerbreadths away, or 1 to 2 cm from the costal margin and iliac crest, respectively, is the planned location of the two 8-mm instrument ports.
Volume 134, Number 5 • Robotic Rectus Abdominis Muscle Harvest A Ultra Veress Needle (Ethicon, Somerville, N.J.) is used to access the peritoneum and attain insufflation using standard technique and pressure parameters (Fig. 3). Once pneumoperitoneum is achieved, the port sites are confirmed or adjusted. The goal of the ports is to be able to access the entire length and width of the rectus muscle, including the pedicle. The most difficult part to dissect is the medial edge because of the steep upward angle that must be taken from the contralateral side. The more lateral the instrument ports, the shallower this angle; however, the lateral extent of the port is limited by the peritoneal reflection that marks the beginning of the retroperitoneum. Once port location is determined, a no. 15 blade is used to cut the skin. A 12-mm port is placed using the corresponding trochar. The robotic endoscope can then be inserted and held by hand to visualize placement of the remaining two 8-mm ports (Fig. 4). Docking and Instrument Placement The surgical robot (da Vinci; Intuitive Surgical, Sunnyvale, Calif.) is brought into position perpendicular to the patient on the ipsilateral side to the muscle being harvested (opposite side from the ports) until the camera arm is flexed at 90 degrees at the elbow (Fig. 5). The central column of the robot is positioned at the level of the umbilicus. The camera port is then docked. Arms 1 and 2 are brought in from the sides with the elbows akimbo to not conflict with the camera arm. The two 8-mm ports are docked and instruments placed. A Cadiere Grasper (Intuitive Surgical) is used in the
Fig. 3. A Varis Needle is used to access the peritoneum and attain insufflation using standard technique and pressure parameters. Once pneumoperitoneum is achieved, the port sites are confirmed or adjusted.
Fig. 4. Once port location is determined, a no. 15 blade is used to cut the skin. A 12-mm port is placed using the corresponding trochar. The robotic endoscope can then be inserted and held by hand to visualize placement of the remaining two 8-mm ports. Here, all three ports are in place and the robot is ready to be docked.
nondominant arm (arm 2 for right-handed people and arm 1 for left-handed people), and the monopolar cautery or Hot Shears (Intuitive Surgical) is placed in the dominant arm. The camera is angled to visualize the instruments as they enter the peritoneal cavity, preventing injury to internal organs that may result during blind entry.
Fig. 5. Docking the robot. The surgical robot (da Vinci) is brought into position perpendicular to the patient on the ipsilateral side to the muscle being harvested (opposite side from the ports) until the camera arm is flexed at 90 degrees at the elbow. The central column of the robot is positioned at the level of the umbilicus. The camera port is then docked. Arms 1 and 2 are brought in from the sides with the elbows akimbo to not conflict with the camera arm. The two 8-mm ports are docked and instruments placed.
Plastic and Reconstructive Surgery • November 2014 Muscle Harvest The surgeon then sits at the console and performs the robotic dissection (Fig. 6). (See Video, Supplemental Digital Content 1, which displays a robotic dissection, available in the “Related Videos” section of the full-text article on PRSJournal. com or, for Ovid users, at http://links.lww.com/PRS/ B117.) First, the deep inferior epigastric pedicle is identified. The peritoneum overlying the pedicle is opened sharply and the vessels are dissected from their origin at the external iliac artery and vein to their entrance into the rectus muscle.
Fig. 6. The surgeon’s console is like an airplane cockpit. All the controls for the camera and instruments are available on a touchscreen. The effector arms are manipulated using two hand-controlled mechanisms in the console. Here, a dual-console system is being shown. Instruments can be passed from one surgeon to the other for teaching purposes and the teacher can “telestrate” on the screen so the learner can be guided.
Next, the posterior sheath is opened along the length of the muscle, just lateral to the midline. This exposes the medial edge of the muscle, which is then grasped, retracted downward, and carefully dissected off of the anterior sheath along its entire length from pubis to costal margin. Neurovascular structures that enter the rectus muscle laterally from the intercostal system and perforators from the deep inferior epigastric artery/vein are both easily identified and controlled during the muscle dissection. These structures can either be cauterized or clipped. The size threshold for this decision is similar to that for the open approach but slightly more conservative because of the more limited access for hemostasis. Care should be taken to separate inscriptions from the anterior sheath without damaging either. To aid the dissection of the inscriptions, the anterior rectus sheath is dissected both above and below the inscriptions, as in the open harvest technique. Gravity is an assistant in this effort, as the muscle hangs away from the sheath increasingly during dissection. When the entire width of the muscle has been dissected, the posterior sheath will be visible on the lateral side of the muscle. The posterior sheath can be divided here, in which case a strip will remain with the muscle, or it can be dissected off of the muscle and repaired following harvest. Currently, there is no evidence that one of these techniques is more effective than the other. The muscle is now bipedicled and otherwise free. The proximal and distal muscle can be divided using electrocautery or bipolar cautery. At the costal margin, the superior epigastric vessels can be clipped or cauterized; at the pubic insertion, the muscle should be divided below the entry of the pedicle. At this point, the muscle is islanded on the pedicle, and if a free flap is intended, a laparoscopic or robotic clip (Weck Clip; Intuitive Surgical) can be used to divide the pedicle, and either a laparoscopic Anchor retrieval sac through an existing port (J.C.S.) or a small public hairline incision (J.P. and D.H.S.) can be used to extract the muscle. If the muscle is remaining pedicled for use in the pelvis, the robot is undocked and inset either robotically using the “prostatectomy” ports or open through the perineum in the case of an abdominoperineal resection.
RESULTS Video. Supplemental Digital Content 1, which displays a robotic dissection, is available in the “Related Videos” section of the fulltext article on PRSJournal.com or, for Ovid users, at http://links. lww.com/PRS/B117.
All cases were completed robotically by three surgeons at three institutions. One of the surgeons participating in this study performs rectus harvest as the only indication for robotic surgery
Volume 134, Number 5 • Robotic Rectus Abdominis Muscle Harvest in his practice; another performs robotic harvest of both the rectus and latissimus muscles; and the senior author has a diverse robotic practice with multiple indications, including muscle harvest, transoral reconstruction of the oropharynx, and microsurgical anastomoses. All participating surgeons reported a steep learning curve for this particular procedure, indicating that it is quickly adopted and incorporated into general practice. All three have extensive experience and are comfortable with open techniques. In this series, four muscles were harvested for lower extremity free flaps and six muscles were used as pedicled flap in the pelvis. Average robotic setup time was 15 minutes (range, 10 to 32 minutes). Average robotic harvest time was 45 minutes (range, 31 to 126 minutes). Two 8-mm ports and one 12-mm port were used in each case. There were no surgical complications. All muscles were completely viable following harvest and there were no conversions to open technique. There was one surgical complication, a stage I decubitus ulcer resulting from a long, multiservice case. Representative cases for free (case 1) and pedicled (case 2) flaps are included.
Fig. 7. Case 1. After having an exposed and infected arthroplasty endoprosthesis, this patient received a robotically harvested rectus muscle to cover the prosthesis. The muscle can be extracted using a small incision in the pubic hairline or through one of the ports using a laparoscopic retrieval bag.
CASE REPORTS Case 1 A 30-year-old female marathon runner presented for right lower extremity limb salvage. Her medical history was remarkable for reticular cell sarcoma of the right lower thigh that was treated with resection followed by chemotherapy and radiation therapy. She remained active, in spite of severe atrophy of the affected leg muscles. Because of worsening arthritis, she underwent a right knee arthroplasty. Two months postoperatively, the incision dehisced and she developed hardware-related infection. After washout and débridement, she underwent prosthesis exchange and negative-pressure wound therapy. Because her native musculature was atrophied and irradiated, there was no local muscle available for reconstruction. The decision was made to use a free rectus abdominis muscle free flap for limb salvage. A robotic muscle harvest was performed and the flap anastomosed end to side to the distal superficial femoral vessels, providing well-vascularized tissue over the exposed tendon and bone. The muscle was skin grafted and she went on to heal uneventfully (Figs. 7 and 8).
Case 2 A 62-year-old man presented with a history of high-risk prostate cancer. He received preoperative radiotherapy. Because his tumor was close to the rectum, plans were made for the patient to undergo radical robotic prostatectomy, possible robotic low anterior resection, and possible robotic rectus abdominis muscle flap for interposition between the coloanal anastomosis and ureterovesicostomy, to prevent rectovesicular fistula. During his prostatectomy, the rectum was injured because of the proximity of the tumor, and a robotic imbricating repair was performed by a gastrointestinal surgeon. Port sites and robot position were
Fig. 8. Case 1. The donor site is shown for the same patient as in Figure 7 . The scars are three small incisions on the contralateral side to the muscle being harvested. Incisional morbidity is very low, and there is no bulge appreciated. changed, and a robotic rectus abdominis flap was performed. An umbilical hernia repair was also performed robotically using biological mesh. The robot was redocked to the prostate ports and the muscle was sutured to the pelvic floor between the rectum and the bladder. The ureterovesicostomy was then performed robotically and an ileostomy was brought up laparoscopically to protect the rectal repair.
DISCUSSION In this article, we have demonstrated the safety and feasibility of harvesting the rectus
Plastic and Reconstructive Surgery • November 2014 abdominis muscle flap robotically in a case series of 10 patients. This approach has wide applicability as a free flap for scalp and extremity coverage and as a pedicled flap for abdominopelvic reconstruction. Incisional morbidity is eliminated using this technique, and there does not appear to be a risk for hernia or bulge, although at less than 1 year of follow-up definitive conclusion would be premature. An advantage of the described technique is that the muscle is much more accessible from inside than from outside. The intraabdominal view provides complete and excellent visualization of the entire length of the muscle and the entire course of the deep inferior epigastric pedicle before any dissection begins. The history of minimally invasive innovations of previously open approaches is perhaps the most significant development and trend in modern surgery. Robotic surgery appears to be the next step in the evolution of minimally invasive efforts, and the improvements in visualization and precision have been well demonstrated.11–13 There are several features that account for the rise of robotic surgery to preeminence among the surgical subspecialties.14,15 First, the robot is capable of superhuman levels of precision, accounted for by 100 percent tremor elimination and 5:1 motion scaling. In addition, high-definition, three-dimensional optics with the capacity for computer-augmented reality (such as indocyanine green image overlay and stereotactic computed tomographic and magnetic resonance imaging guidance) create a visual system beyond what is possible with a microscope, an endoscope, or the human eye. The instrumentation itself does not require the reverse logic of laparoscopy, and 7 degrees of freedom at the tips of the instruments provide a versatility that is unparalleled in either laparoscopic or conventional instrumentation. As remarkable as these features are, they represent a technology still in its very nascent form. We are still operating in a single-vendor, single-software platform, robotic surgical world. We can soon expect multiple vendors, exponentially more specific and refined robotic technology, and wider surgical applications at a lower cost. In plastic surgery, we have been slow to adopt minimally invasive technology. Being surgeons of the “skin and everything within,” we generally have wide incisional access to surgical fields. As a result, we have not developed a tradition of minimally invasive techniques, and even an introduction to the robot is absent from routine plastic surgery training. Perhaps for this reason, some of the more subtle opportunities to use this
technology for the benefit of our patients have eluded the specialty, with some exceptions.16–19 A lack of specialty-specific training should not, however, deprive our patients from receiving the benefit of such approaches when they are appropriate. This is particularly the case with complex, minimally invasive abdominopelvic surgery. Just as we have refined our techniques and technologies for our patients, general surgeons, urologists, and gynecologist have refined minimally invasive, intraperitoneal surgery such that increasingly complex surgery is being performed without laparotomy. Robotics has pushed this boundary even further. At the senior author’s institution, for instance, it is not unusual for anterior pelvic exenterations, radical cystoprostatectomies, and abdominopelvic resections to be performed robotically by urologists, colorectal surgeons, and plastic surgeons whose robotic skills are all enlisted in the service of a single patient. As our reconstructive group has previously published, irradiated abdominopelvic resection defects have better outcomes with vascularized tissue, usually in the form of a vertical rectus abdominis muscle flap to obliterate dead space and reinforce the perineal incision.20 Furthermore, it is well recognized by colorectal and plastic surgeons alike that irradiated rectal repairs benefit from vascularized coverage.21–23 In many cases, the skin is an important component of the vertical rectus abdominis muscle, particularly when there is a vaginal lining or perineal skin defect. The abdominal adipose tissue of the vertical rectus abdominis muscle can also be desirable when demand for dead space obliteration of the pelvis is significant. For these reasons, the vast majority of pelvic reconstructions performed by the authors are traditional vertical rectus abdominis muscle flaps. Such considerations highlight the importance of patient selection in using a muscle-only approach to pelvic reconstruction. The ideal patient is one in whom dead space volume is low to moderate, there is not significant loss of the vaginal mucosa or perineal skin, and the abdominal adiposity creates an oversupply of tissue for the reconstructive demands. When these conditions are met, however, it is unfortunate for reconstruction to serve as the only indication for a laparotomy when multiple other services have provided so much value by eliminating the need for one. Plastic surgery at a cancer center is a support service, creating wraparound operations so that the other service lines can function at peak performance levels and the top of their training. As
Volume 134, Number 5 • Robotic Rectus Abdominis Muscle Harvest these new scenarios emerge and present clinical challenges, we must adapt our skills and services to meet them, or our specialty will be left behind. The robotic rectus harvest meets this growing demand using a straightforward, reproducible harvest technique for providing well-vascularized tissue within the abdomen and pelvis and maintaining minimal access. With the addition of a simple extraction procedure, this technique is equally applicable to extraperitoneal use throughout the body.
CONCLUSIONS The rectus abdominis muscle provides a highly versatile flap, but its usefulness is limited by incisional morbidity and violation of the anterior rectus sheath. Robotic harvest of the rectus muscle is a straightforward, reproducible, and expeditious technique that eliminates violations of the rectus sheath and reduces total incisional length to approximately 2 inches. This harvest technique has broad applications for both free flaps and pedicled flaps and even broader implications for the role of plastic surgery as an integrated service line in a changing world. Jesse C. Selber, M.D., M.P.H. The University of Texas M. D. Anderson Cancer Center 1400 Pressler Street, Unit 1488 Houston, Texas 77003 [email protected]
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