**8.3 Surgical procedure**

The precise liver procedure to be performed will be dependent upon the type of liver resection to be performed. Below a description of anatomical and nonanatomical liver resections is discussed.

#### *8.3.1 Anatomical/major robotic liver resection*

Prior to any form of liver resection the central venous pressure is lowered to less than 5 mmHg in order to reduce blood loss that is used in conjunction with reverse Trendelenburg position for the same reason [26]. For anatomical or major robotic liver resection there are three surgical steps that have been recommended for safe resection outlined in **Table 2** and are similar to open liver surgery.

For major robotic liver resections the falciform ligament is usually divided with a vascular stapler or robotic stapler followed by a retrograde cholecystectomy using the same principles of laparoscopic cholecystectomy. In the case of left hepatectomy the left triangular ligaments can now be divided in order to mobilise

the left lobe of the liver. A Nylon taped maybe passed at this point for future Pringle use although this is not necessary in all cases [27].

Next the relevant hepatic pedicle is then dissected using a combination of robotic monopolar hooks and/or bipolar forceps. For major hepatectomy the right or left hepatic artery is dissected first and clearly identified. IOUS may be utilised after selective clamping of the dissected artery to ensure satisfactory flow within the future liver remnant. Once satisfactory flow is confirmed the desired artery can be divided between prolene sutures, surgical clips or Hem-O-locks®. Next the relevant portal vein is completely dissected and selective stitches or ligatures are applied on the small branches if present. The portal vein is then divided between robotic clips/Hem-O-locks or sutured with either 4-0 or 5-0 prolene. Generally an extrahepatic dissection of the bile duct should be performed only when the anatomy is clear and confluence of the biliary ducts is low. In the latter ICG fluorescence can be easily used at any point and can help identify the biliary anatomy and used with the Firefly setting on the robotic system. For right hepectomy hepatocaval dissection the subsequent step following hilar dissection. Specifically the lateral reflection of the peritoneum is dissected using the hepatocaval plane as a guide. The third arm of the robot can then be used and a retractor deployed to lift the inferior surface of the right liver lobe to expose the IVC in analogous manoeuvre to open surgery. The retrohepatic veins can be divided using either sutures or surgical clips. Clips can also be placed for accessory hepatic veins of minor calibre or to further The liver is progressively dissected off the IVC until the inferior aspect of the right hepatic vein is visible and signals the end of this part of the dissection.

Transection of the liver is the last step of the operation. Parenchymal transection should follow the ischemic demarcation line and start at the anterior aspect of Cantile lines for a right hepatectomy. Many retraction measures can be employed to ensure effective retraction of the liver including stay sutures, rubber rings or surgical instruments. As discussed above many liver surgeons would consider robotic harmonic scalpel as the tool of choice for parenchymal transection. Liver transection is performed layer by layer proceeding in a superficial to deep manner in the same plane to maintain control of vessels and bleeding. Moreover superficial bleeding can be controlled with appropriate energy devices whilst larger vessels may require suturing and/or surgical clips. As the resection proceed deeper into the liver most surgeons would utilise surgical stapling devices to control venous structures such as segment 5 and 8 branches as well as the right/left hepatic vein. The liver is then completely mobilised by sectioning the remaining peritoneal attachments with assistance of the bedside surgeon. In the case of left lateral sectionectomy following left triangular division robotic resection can be completed by remaining lateral to the falciform ligament and completed parenchymal transection with robotic harmonic scalpel and vascular staplers. For segmentectomy the relevant portion of the liver is mobilised and IOUS used to identify selective pedicles prior to transection.

Following transection the raw surface of the remaining liver should then be examined for bleeding and bile leaks. At the end, haemostatic agents such as fibrin glue, Surgicel®, argon plasma can be applied to the remaining surface as a sealant.


**229**

**Table 3.**

*Robotic Liver Surgery*

haemostatic agents.

*DOI: http://dx.doi.org/10.5772/intechopen.87995*

*8.3.2 Non-anatomical robotic liver resection*

**9. Current results of robotic liver surgery**

tumours presented a technical challenge.

*Types and frequencies of robotic liver resections.*

under direct laparoscopic vision.

Finally, the specimen is placed in an endoscopic bag and extracted through a small Pfannenstiel incision or through the site of a previous scar. Closed suction drains in the subhepatic and subdiaphragmatic area is used. The robotic cart is removed from the operative field, pneumoperitoneum is stopped and the trocars are extracted

In our experience the Pringle manoeuvre has to be rarely used for NARs but when there is a need to secure more control on the liver inflow, the hepatic pedicle is prepared and a tourniquet is created using an umbilical tape. NARs are generally reserved for liver lesions that are superficial, subcapsular or easily visualised. As discussed above the main tool used for parenchymal transection is the robotic harmonic scalpel and it is ideally suited to perform NARs. Prior to commencing transection the resection line can be marked with diathermy which also allows the robotic harmonic scalpel to be positioned correctly and may mandate the switching of the robotic harmonic scalpel between different robotic arms. As described above transection is recommended to be performed in a layer-by-layer fashion. The fourth robotic arm can be used to aid retraction such that there is minimal traction on the lesion itself. Once the resection is completed haemostasis is achieved with a combination of the robotic energy instruments and topical

Early experiences with using a robot in cholecystectomy demonstrated equivalent results to the laparoscopic approach. These early surgical reports served to show that robotic approaches were feasible for liver surgery [28, 29]. In most institutions robotic cholecystectomy is reserved for those surgeons completing approved training pathways/accreditation before commencing upon more complex procedures. Generally for cholecystectomy robotic surgery does not offer any significant advantage over the laparoscopic approach particularly when cost-benefit is considered. Below we discuss the current results for robotic liver resection. On reviewing the available literature it is evident that there are clear contraindications to the robotic liver surgery including invasion of major hepatic vessels and extension into the diaphragm necessitating diaphragmatic resection. There is no predetermined limit regarding the size of lesions that can be resected but very bulky

NAR/segmentectomy 87 Left lateral sectionectomy 51 Left hepatectomy 31 Bisegmentectomy 12 Right hemihepatectomy 51 Right trisectionectomy 3 Other 2 Total 237

#### **Table 2.**

*Suggested steps for major robotic liver resection.*

#### *Robotic Liver Surgery DOI: http://dx.doi.org/10.5772/intechopen.87995*

*Liver Disease and Surgery*

use although this is not necessary in all cases [27].

the left lobe of the liver. A Nylon taped maybe passed at this point for future Pringle

Next the relevant hepatic pedicle is then dissected using a combination of robotic monopolar hooks and/or bipolar forceps. For major hepatectomy the right or left hepatic artery is dissected first and clearly identified. IOUS may be utilised after selective clamping of the dissected artery to ensure satisfactory flow within the future liver remnant. Once satisfactory flow is confirmed the desired artery can be divided between prolene sutures, surgical clips or Hem-O-locks®. Next the relevant portal vein is completely dissected and selective stitches or ligatures are applied on the small branches if present. The portal vein is then divided between robotic clips/Hem-O-locks or sutured with either 4-0 or 5-0 prolene. Generally an extrahepatic dissection of the bile duct should be performed only when the anatomy is clear and confluence of the biliary ducts is low. In the latter ICG fluorescence can be easily used at any point and can help identify the biliary anatomy and used with the Firefly setting on the robotic system. For right hepectomy hepatocaval dissection the subsequent step following hilar dissection. Specifically the lateral reflection of the peritoneum is dissected using the hepatocaval plane as a guide. The third arm of the robot can then be used and a retractor deployed to lift the inferior surface of the right liver lobe to expose the IVC in analogous manoeuvre to open surgery. The retrohepatic veins can be divided using either sutures or surgical clips. Clips can also be placed for accessory hepatic veins of minor calibre or to further The liver is progressively dissected off the IVC until the inferior aspect of the right

hepatic vein is visible and signals the end of this part of the dissection.

Transection of the liver is the last step of the operation. Parenchymal transection should follow the ischemic demarcation line and start at the anterior aspect of Cantile lines for a right hepatectomy. Many retraction measures can be employed to ensure effective retraction of the liver including stay sutures, rubber rings or surgical instruments. As discussed above many liver surgeons would consider robotic harmonic scalpel as the tool of choice for parenchymal transection. Liver transection is performed layer by layer proceeding in a superficial to deep manner in the same plane to maintain control of vessels and bleeding. Moreover superficial bleeding can be controlled with appropriate energy devices whilst larger vessels may require suturing and/or surgical clips. As the resection proceed deeper into the liver most surgeons would utilise surgical stapling devices to control venous structures such as segment 5 and 8 branches as well as the right/left hepatic vein. The liver is then completely mobilised by sectioning the remaining peritoneal attachments with assistance of the bedside surgeon. In the case of left lateral sectionectomy following left triangular division robotic resection can be completed by remaining lateral to the falciform ligament and completed parenchymal transection with robotic harmonic scalpel and vascular staplers. For segmentectomy the relevant portion of the liver is mobilised and IOUS used to identify selective pedicles prior

Following transection the raw surface of the remaining liver should then be examined for bleeding and bile leaks. At the end, haemostatic agents such as fibrin glue, Surgicel®, argon plasma can be applied to the remaining surface as a sealant.

Step 1 Division of the Falciform ligament ± cholecystectomy Step 2 Portal pedicle dissection and liver mobilisation

**228**

**Table 2.**

to transection.

Step 3 Liver transection

*Suggested steps for major robotic liver resection.*

Finally, the specimen is placed in an endoscopic bag and extracted through a small Pfannenstiel incision or through the site of a previous scar. Closed suction drains in the subhepatic and subdiaphragmatic area is used. The robotic cart is removed from the operative field, pneumoperitoneum is stopped and the trocars are extracted under direct laparoscopic vision.
