Robotic distal pancreatectomy

Indications

The indications for robotic distal pancreatectomy are similar to those for traditional laparoscopic approaches, ranging from cystic neoplasms to malignant diseases of the distal pancreas. However, robotics appears to have several important advantages over laparoscopy, which has been shown to provide short- and long-term oncologic outcomes comparable to open distal pancreatectomy, with a shorter hospital stay and less intraoperative blood loss. ^, Although the long-term oncologic outcomes require further assessment, studies suggest that robotic approaches provide higher R0 resection rates, shorter length of hospital stay, and lower conversion rate to an open procedure than laparoscopic approaches. ^, The cost-effectiveness appears to be similar to or even better than that of laparoscopic distal pancreatectomy. Technically, robotics provides enhanced dexterity, increased range of motion of instruments, ergonomic wrist articulation, and a close and steady three-dimensional view of structures in deep cavities. These features are particularly useful in pancreas surgery, which requires precise dissection around the deep vital structures. In distal pancreatectomy, the use of robotic systems is especially advantageous when dissecting around the splenic vein to preserve the spleen, performing a thorough lymphadenectomy, and oversewing the pancreas cut edge. It also makes it easier to perform vascular and bowel anastomosis when necessary. Importantly, the full wrist articulation of robotic systems mimics the surgeon’s hands and allows the surgeon to apply the technical principles of open surgery to minimally invasive approaches. Therefore, it is relatively easy for experienced pancreas surgeons to adopt the robotic techniques.

In contrast, the lack of haptics is a major limitation of robotic surgery. Not having a sense of touch makes it a challenge to appreciate tissue texture such as mass, friction, elasticity, and relational constraints, which can lead to unwanted tension on delicate structures, inappropriate dissection planes, and incorrect perception of a tumor margin or even the presence of a tumor itself. Applying haptic feedback to robotic surgery remains an ongoing research focus. At the moment, the central approach to overcome this issue is to augment active vision with active touch, a technique known as vision-based haptic exploration. This technique is used when controlling various service robots in general. Applying the technique to surgery requires sufficient experience and sound technical skills in open as well as robotic surgery. The use of intraoperative ultrasound, routine frozen section pathology consultation, and the presence of a capable bedside assistant also help maximize the success rate of robotic distal pancreatectomy, as described in our procedure below.

Patient selection is the key to a successful robotic distal pancreatectomy in the early stages of the learning curve. Although robotic systems can provide advantages when dissecting through fibrotic tissue or performing en bloc resection of multiple organs, it is preferred to avoid patients with extensive disease that would require such procedures until vision-based haptic exploration can be comfortably performed. Once the surgeon is comfortable with a straightforward distal pancreatectomy with or without splenectomy, patient selection can be based on the surgeon’s comfort level. Distal pancreatectomies involving additional procedures such as enterectomy, adrenalectomy, nephrectomy, and celiac axis resection have been successfully performed robotically.

Operating room setup and patient positioning

The patient is placed in a supine position on a table equipped with footboards. In general, two large-bore peripheral intravenous lines and an arterial line are used for vascular access. After the induction of general anesthesia, an orogastric tube and urinary catheter are inserted. The patient will have both arms tucked and is strapped over the chest and lower extremities, to be placed in reverse Trendelenberg position with a right lateral tilt of approximately 30 degrees ( Fig. 30.1 ). The abdomen is treated with chlorhexidine gluconate from the nipples down to the superior border of the pubic symphysis and bilaterally to the midaxillary lines. Intravenous cefazolin is administered to prevent surgical site infection within an hour of skin incision and is re-dosed during the operation. A dose of subcutaneous heparin is given to prevent deep vein thrombosis, and methadone is administered to help postoperative pain control.

Key operative steps

Port placement

The abdominal cavity is accessed with a Veress needle through a small stab incision at Palmer’s point. Once insufflation is completed, port insertion sites are marked with a marking pen. Four robotic ports and one assistant port are lined horizontally in a slight V-shaped configuration ( Fig. 30.2 A). For the robotic camera port, a midline vertical incision is made infra-umbilically and is extended at the end of the case for specimen extraction. However, based on body habitus, port placement often requires adjustment. For example, in patients with a long xiphi-umbilical length, the horizontal line is moved more cephalad above the level of the umbilicus ( Fig. 30.2 B). Here, the ports are lined up with less angulation to maintain an adequate working distance of the ports from the target specimen. Based on the markings, a robotic 8-mm port is first placed through the periumbilical vertical midline incision ( Fig. 30.3 ). A robotic 30-degree camera is inserted through the 8-mm port, and the abdomen is inspected for any signs of peritoneal or visceral metastasis in the setting of malignant disease. Additional ports are then placed under direct visualization. The robotic cart is docked from the right side of the patient, and targeted to the gastric fundus. The robotic arms are docked to the ports and the robotic instruments are inserted (refer to Fig. 30.2 ).

In patients with possible intraperitoneal adhesions secondary to past surgical procedures or a history of pancreatitis, the insufflated abdomen is accessed with a 5-mm optical port under direct visualization with a 5-mm 0-degree laparoscopic camera at Palmer’s point or at the midline by the umbilicus. The laparoscopic camera is switched to a 30-degree camera, and the adhesions are taken down laparoscopically to a level that allows placement of robotic trocars and execution of the subsequent robotic operation.