The three basic components of the da Vinci system are a patient-side cart, a vision system, and a surgeon's console. The patient-side cart has four robotic arms that are attached or “docked” to trocars that are placed in the abdomen in strategic locations. One arm holds the endoscope (either an 8.5-mm or 12-mm diameter, with a 0-degree or 30-degree configuration) and the other three arms hold miniaturized 8-mm (or 5-mm) instruments. Some surgeons employ only two of these arms. The vision system delivers a high-definition 3D image to the viewer in the surgeon's console, and 2D images to other monitors in the operating room.
From the console, the surgeon uses hand controllers and foot pedals to move the instrument and camera robotic arms of the patient cart via a process of computer algorithms that reduce tremor and employ motion scaling to deliver precise movements within the surgical field. The robotic instruments have seven degrees of freedom that replicate or surpass the motions of the human hand, allowing the surgeon to essentially perform open surgery through laparoscopic access.
A uterine manipulator is typically used for traditional laparoscopic myomectomy procedures, and robotic myomectomy is no exception. I typically use a standard HUMI manipulator (Harris-Kronner Uterine Manipulator Injector by CooperSurgical), and I dock the patient-side cart between the patient's legs rather than on the side. This placement of the patient cart enables me to employ a four-arm approach for robotic myomectomy, which I prefer, rather than a three-arm approach. With this configuration, I can use one of the instrument arms to manipulate the uterus instead of relying on a bedside assistant having vaginal access to do this task.
One arm, at or above the umbilicus, holds the endoscope. At the beginning of the procedure, an instrument arm on the left side holds a bipolar device (a PK Dissector that is made by Gyrus ACMI for Intuitive Surgical), and one of two instrument arms on the right side holds the robotic scissors (the da Vinci HotShears). The other right-handed instrument arm holds tenaculum forceps, which can be used to manipulate the uterus or fibroid in any direction. At the end of the procedure, for closure of the hysterotomy incision, needle drivers may be substituted for the PK Dissector and HotShears and the ProGrasp (part of the da Vinci Surgical System) substituted for the tenaculum.
The ports or trocar sites are placed after establishing pneumoperitoneum, typically starting with a Veress needle at the primary or camera site. The camera site is chosen based on the size of the uterus, and an attempt is made to keep at least 10 cm (one handbreadth) between the fundus or top of the presenting fibroid and the camera trocar site.
The left lower quadrant port is placed at least 4–5 cm (three fingerbreadth) directly cephalad to the anterior superior iliac spine. The right lower quadrant port is similarly placed, and then the right upper quadrant port, with the distance between the two right ports being at least one handbreadth (10 cm) in a medial direction. The assistant's port is placed in the left upper quadrant near Palmer's point (the point 3 cm below the last rib in the left midclavicular line). (See image 3.)
One can also “side dock” the patient cart using this configuration to provide more access to the vagina when necessary, and the ports can be adjusted higher or lower on the abdomen depending on the size of the uterus. Clearly, there is a limit to how high one may traverse on the abdomen before entering the thoracic cavity using these principles. There are cases, though, in which the camera port may end up below the fundus of the uterus.
Spacing of the arms also can be negatively affected by a lower body mass index (BMI), but every attempt should be made to obtain at least 8–10 cm of spacing between the robotic port sites to minimize or prevent collision of the instrument and camera arms externally and internally. Caution also must be employed to place the trocars perpendicular to the plane of the abdominal wall; this prevents tunneling of the port, which would defeat the purpose of the strategic placement of the arms externally.
The use of two robotic instruments on the patient's right side is key. Having two right-handed instruments gives the surgeon the ability, at any point in the operation, to manipulate the uterus or the fibroid(s) with two graspers, and to be fairly self-sufficient in enucleating and retracting the fibroid(s) as well as in closing the myometrium.