Robotics for benign gynecology

Patient positioning

A robotic-assisted procedure begins with proper patient positioning for surgical success and patient safety. Once the robot is docked, repositioning is challenging and disruptive. The first step for pelvic surgery is therefore to secure an anti-slip apparatus to the table to prevent the patient from sliding cephalad while in Trendelenburg position. The patient is placed directly on the anti-slip apparatus. Use of other materials, such as a draw sheet, should be avoided as these decrease friction and increase risk of slippage. A gel donut or foam pillow should also be placed under the patient’s occiput to avoid ischemic necrosis and/or alopecia from pressure points while in Trendelenburg.

The patient is placed in a low dorsal lithotomy position using boot stirrups ( Fig. 37.1 ). Hips should be flexed 60 to 170 degrees with abduction of 90 degrees and minimal external rotation. Knees are flexed 90 to 120 degrees. Heels should be flush with the back of the stirrup and all potential pressure points should be well padded. The buttocks should be positioned just off the edge of the table with the sacrum fully supported. If the patient is not placed down far enough on the table, then uterine manipulation will be limited during the case due to collision with the end of the table. If the patient is down too far, this will put increased pressure on the patient’s lower back, resulting in possible injury.

Both arms should be padded and tucked at the patient’s sides in a thumbs-up position. This provides space for the surgeon to operate from the level of the patient’s shoulder and angle directly toward the pelvis. Risk of brachial plexus injury increases with outstretched arms and prolonged Trendelenburg position, especially with the use of shoulder braces. Shoulder braces should be avoided where possible. If used, they should be placed over the acromioclavicular joints bilaterally. For obese patients, sleds or bed extenders may be used to facilitate arm tucking. A bariatric bed that allows the table to be lowered closer to the ground will allow more clearance anteriorly for robotic arms.

Lastly, a tilt table test is performed. The patient is placed in Trendelenburg position and observed for evidence of cephalad slide. The degree of Trendelenburg should be enough to allow for mobilization of the bowel out of the pelvis to adequately visualize the pelvic anatomy. It often does not require the maximum Trendelenburg position of 30 to 40 degrees. A pilot study in which surgeons were blinded to degree of Trendelenburg used demonstrated a mean of only 16 degrees required to adequately visualize the pelvis. Overall, the total time the patient spends in Trendelenburg position should be minimized to avoid injury secondary to slippage or physiologic changes associated with Trendelenburg positioning. Steep Trendelenburg position for more than 3 hours may predispose a patient to potential brachial plexus injury, corneal abrasions, laryngeal edema, cerebral edema, and posterior ischemic optic neuropathy.

Uterine manipulation

Adequate uterine manipulation is important for triangulation and exposure of the pelvic anatomy. The uterine manipulator is also used to increase operating distance away from vulnerable structures, such as the bladder and bowel. The addition of a colpotomy ring or cup aids in lateralizing ureters during hysterectomy. There are multiple manipulators available that are selected based on availability and surgeon preference.

Port placement

Robotic ports are placed to facilitate surgery deep in the pelvis while taking into consideration the patient’s unique anatomy. Typically, the first entry is made at the umbilicus and this port is used for the camera. This site may be adjusted 2 to 3 cm cephalad due to an enlarged uterus or just to the left of the midline for thin patients to avoid clashing with the first and third robotic arms. Alternative entry points such as the left upper quadrant (Palmer’s point) is used in patients with prior midline vertical incisions or umbilical hernias to avoid injury to the underlying bowel. Open entry technique with a 2.5 to 3.5 cm umbilical incision and placement of a multiport apparatus can be used for single site surgery or for retrieval of large specimens, such as uterine fibroids following myomectomy.

After establishment of pneumoperitoneum and Trendelenburg positioning, additional ports are placed as needed. Ideally, robotic ports are placed at least 8 to 10 cm apart. These can either be placed in an arc around the umbilicus ( Fig. 37.2A ), in a “W” conformation ( Fig. 37.2B ) for the Si da Vinci robotic platform, or straight across or at a slight arc for the Xi da Vinci robotic platform ( Fig. 37.2C ).

The surgeon must then decide on how many robotic arms to use and whether to use an assistant port. Many gynecologic procedures can be accomplished cost effectively with three robotic arms and without the need for an assistant port. The fourth arm may be necessary for more advanced procedures, such as with large masses, patient obesity, and difficult dissections. It can be helpful in providing added countertraction, developing anatomical spaces, supporting uterine manipulation, and retracting tissue for visualization of the operative field.

An assistant port allows the bedside assistant to irrigate, suction, provide countertraction, pass sutures, and provide tactile feedback ( Fig. 37.2D ). During myomectomy, upper quadrant placement of the assistant port allows for application of cephalad traction on fibroids, whereas a lateral assistant port allows for less interaction with the robotic arms.

For right-handed surgeons, we recommend placing the fourth arm on the right to provide traction-countertraction while operating with the right hand and vice versa for left-handed surgeons. The assistant port, if used, is then placed opposite the third robotic arm in the upper quadrant or the lateral-most location. Note that with the Xi platform, the 8 mm camera can be placed or moved to any of the robotic ports. A lateral camera position and/or a 30-degree lens may help improve visualization in setting of large uteri or fibroids.

Docking

Once all trocars are placed, the next critical step in performing a successful robotic-assisted procedure is docking the robot. Typically for the Si da Vinci robotic platform, there are three options for docking the robot: central docking, side docking, and parallel docking ( Figs. 37.3A and 37.3B ). Central docking is when the robot boom is positioned between the patient’s legs. This allows for best direct angle of instruments with regard to robotic arm attachments, but prohibits ease of access to the vagina for uterine manipulation or tissue extraction. Side docking involves the robot being positioned at an angle in line with the camera port and contralateral shoulder, on the patient’s right for right-handed surgeons and vice versa for left-handed surgeons. This allows for adequate angulation of the robotic instruments and access to the vagina but is often more time-consuming to direct the team for proper positioning. Lastly, parallel docking involves positioning the robot parallel to the bed (on the right for right-handed surgeons and vice versa for left-handed surgeons). For the Xi da Vinci robotic platform, docking position is less important as the instruments rotate around an adjustable central boom and contain a targeting positioning system for optimization of robotic arm angles. The instrument arms should be positioned to achieve the greatest angle between instruments to prevent collision and maximize pitch and aft movements ( Fig. 37.4 ).

Instrumentation

Proper instrumentation is important to perform robotic surgery successfully. There are many instruments available, and care should be used to select multifunction instruments to increase efficiency and decrease cost. A bipolar grasper or PlasmaKinetic (PK) dissector is placed in the contralateral nondominant hand to grasp, coagulate, and seal vessels. A monopolar scissors, ultrasonic scalpel, or vessel sealer is typically placed in the dominant hand to facilitate dissection. The needle driver is also used by the dominant hand. A ProGrasp forceps, single tooth tenaculum, or other retractor can be placed in the fourth arm to provide static countertraction to facilitate dissection. The ProGrasp should not be used to hold the bowel due to excessive force, whereas the small retractor may be used to hold the bowel back.

Procedural details

The steps involved in a robotic-assisted hysterectomy are the same steps as in a conventional laparoscopic hysterectomy. First, the round ligament is incised, and the anterior leaf of the broad ligament is transected down to the level of the cervical isthmus, then dissected medially to create a bladder flap. Next, the posterior leaf of the broad ligament is incised, and the ureter and internal iliac artery and vein are identified. The infundibulopelvic (IP) ligament is isolated by creating a window in the middle leaf of the broad ligament. This maneuver drops the ureter posterior and lateral from the area of dissection. If performing an oophorectomy, the IP ligament is then desiccated and transected. If no oophorectomy is performed, then the utero-ovarian ligament is desiccated and transected. It is a current recommendation to perform a salpingectomy at the time of hysterectomy regardless of oophorectomy to reduce the risk of ovarian cancer in the future. This is performed by coagulating and transecting the mesosalpinx laterally to medially to the level of the uterine cornua. The fallopian tube can be left attached to the uterus or removed separately to prevent obscuration of the uterine artery. Next, the uterine artery is skeletonized using blunt and sharp dissection. This procedure is repeated similarly on the contralateral side. The bladder flap is brought down further over the level of the cervical-vaginal junction and bilateral uterine arteries are desiccated and transected. The uterine arteries are then lateralized to the cervix and the colpotomy is carried out in a layered fashion. Bipolar energy use should be minimized during colpotomy to minimize char and decrease risk of vaginal cuff dehiscence.

A bag for tissue containment and extraction may be placed through the vagina and the uterine specimen placed within the bag for retrieval through the vagina. In cases where tissue extraction is difficult or prolonged, the robot may be undocked to allow for increased space for retraction, better visualization, and changes in patient position. After the specimen is removed, the vaginal cuff is repaired with an interrupted or running suture. We recommend the use of an absorbable barbed suture to close the cuff in a running fashion in two layers, with fixation of the cuff to the bilateral uterosacral ligaments for pelvic support. After this step, the pelvis is irrigated, and a low-pressure check is performed by temporarily desufflating the abdomen and then reinflating to ensure hemostasis under physiologic pressures. The robot is then undocked. Cystoscopy is performed to evaluate for patency of the bilateral ureters and bladder injury. We recommend making cystoscopy a routine part of any laparoscopic or robotic-assisted hysterectomy. Lastly, the surgeon may choose to apply an adhesion barrier or fibrin sealant, but routine use of these products is controversial.

Special surgical considerations

Not all hysterectomies are straightforward, and the surgical approach described in the prior section may need to be modified based on anatomy encountered at the time of surgery. As approximately one out of three babies is delivered via cesarean section, it is common to encounter scarring from a prior cesarean section at the time of hysterectomy. This scarring is usually located anterior to the uterus and can involve the bladder and the anterior abdominal wall. Other than prior surgery, endometriosis, prior appendicitis, diverticulitis, and pelvic infection can also lead to significant scarring. Usually, the best approach to hysterectomy in the face of significant scarring is to start from normal anatomy rather than initially tackling the scar directly. This technique allows one to identify normal anatomy and avoid organ injury, as tissue planes are often disrupted and mispositioned in the setting of significant scar tissue. In the setting of anterior adhesions, as commonly found after a cesarean section, it may be easiest to start laterally or posteriorly. As the bladder is often involved in the adhesion, it is often helpful to backfill the bladder with fluid to demarcate its position. When performing adhesiolysis near the bowel or bladder, it is best to minimize use of energy so as to avoid thermal injury. Saline may be used to perform hydrodissection with a laparoscopic suction irrigator device. When anticipating significant scarring posterolaterally, it may be prudent to place lighted ureteral stents prior to starting the procedure to help identify their location and avoid injury. The use of lighted ureteral stents, however, is controversial and largely dependent on surgeon experience and preference.

One benefit of robotic-assisted laparoscopy over conventional laparoscopy is the availability of wristed instruments. These prove useful when operating on large specimens such as a uterus with large fibroids. There are several techniques that may help when operating on a large uterus. As aforementioned, trocar placement should be based on the patient’s anatomy, which includes the surgical pathology. If a uterus extends to the umbilicus, the trocars should be placed more superiorly to best triangulate and target the anatomy. The specimen may also be pulled down into the pelvis during the operation rather than being pushed out of the pelvis to allow greater distance between the camera, operating arms, and specimen. The greater the distance from the camera and instruments, the greater the availability for triangulation. Manipulation is key. Sometimes it is difficult to manipulate a large specimen from uterine manipulation alone. It may help to provide some manipulation from the assistant port with use of a single or double tooth tenaculum. We suggest use of a dilute vasopressin injection prior to use of a tenaculum to reduce bleeding at the site of puncture. Lastly, a thirty-degree camera is beneficial rather than a zero-degree camera when attempting to visualize structures obscured by large fibroids. With the Xi da Vinci robot, the 8-mm camera can be placed through any of the robotic trocars and can be moved to see around structures.

In minimally invasive surgery, when the uterine specimen is too large to be removed intact through the vagina, it must be cut into smaller pieces to either fit through the vagina or through a small incision. This process is called morcellation. Morcellation has recently come under scrutiny due to risk of disseminating occult malignancy, specifically leiomyosarcoma, which is difficult to diagnose preoperatively. The FDA issued a warning against the use of power morcellation in laparoscopic surgery in 2014. During laparoscopy, large specimens can be placed within a containment system, such as a bag, and manually extracted within that system to avoid spillage of tissue. This is done by either cutting the specimen into small pieces with a scalpel or coring the specimen out in one long continuous piece.

During prolonged tissue extraction (>5 minutes), we recommend undocking the robot, taking the patient out of steep Trendelenburg position, and desufflating the abdomen to minimize intracranial and intrathoracic pressure. The uterine specimen may be removed through the vagina or through a mini-laparotomy incision either suprapubically or through the umbilicus. Typically, a “C”-incision or bivalve technique is used for extraction. The uterine specimen is allowed to rotate to provide fresh edges to grasp as the extraction is carried out. The contained extraction system bag is adjusted and pulled tauter as the specimen is removed. The scalpel blade should be changed often as calcified fibroids can dull an edge quickly. Care should be taken to avoid lacerating the bag or any structures that may be adjacent to the bag, such as the bowel, urethra, or vagina. Lastly, a circumferential retraction device may be used outside of the bag to retract and protect the tissue at the opening. This may be performed either vaginally or through a mini-laparotomy incision.

The use of routine bowel prep prior to hysterectomy is controversial. We find it is most helpful to decompress and move the bowel when performing a sacrocolpopexy or lysing extensive adhesions involving the bowel, but not necessarily for most cases.

Single site

Single-site robotic-assisted hysterectomy is an option for improved cosmesis. In general, each step of the single-port procedure has been found to be equivalent in time to a multiport approach to robotic-assisted hysterectomy, except for vaginal cuff closure. The advantages of single-site robotic hysterectomy include improved aesthetics for the patient, allowance for surgeon independence while minimizing the need for a bedside assistant, and automatic reassignment of the robotic arm controls as compared to single site conventional laparoscopy, allowing for more natural movements. Disadvantages include nonwristed instruments, decreased degrees of freedom and triangulation, longer suturing time, and restricted assistant port use.

While there are a variety of single site ports available that are compatible with the robotic arms, Intuitive has a single port that is specifically meant to be used with their single site instruments. To place the trocar, you first make a 2 to 3-cm incision either vertically through the base of the umbilicus or in a “C” or “W” around the umbilicus. We recommend tagging the apices of the fascia with 0-Vicryl or polydioxanone (PDS) suture to use for closure at the end of the case and to aid in placement of the single site port. A circumferential retractor may be used to reduce distance from skin to fascia in those patients with a larger amount of subcutaneous tissue and may ease placement. We then moisten and fold the port to allow ease of entry into the small incision ( Fig. 37.5 ). Once secured, the abdomen is insufflated. Since the arms cross in single-port surgery, the instrument for operating from the right side needs to come down the left trocar and vice versa for the left ( Fig. 37.6 ). See Box 37.1 .