Technique of totally robotic delta-shaped anastomosis in distal gastrectomy.

BACKGROUND: We aimed to clarify the utility of delta-shaped anastomosis (Delta), an intracorporeal Billroth-I anastomosis-based reconstruction technique used after laparoscopy-assisted distal gastrectomy (LADG), in robot-assisted distal gastrectomy (RADG).
METHODS: RADG was performed in patients with clinical Stage I gastric cancer, and reconstruction was performed using Delta. The Delta procedure was the same as that performed after LADG, and the operator practiced the procedure in simulated settings with surgical assistants before the operation. After gastrectomy, the scope and robotic first arm were reinserted from separate ports on the right side of the patient. Then, a port on the left side of the abdomen was used as the assistant port from which a stapler was inserted, with the robotic arm in a coaxial mode. The surgical assistant performed functional end-to-end anastomosis of the remnant stomach and duodenal stump using a powered stapler.
RESULTS: The mean anastomotic time in four patients who underwent Delta after RADG was 16.5 min. All patients were discharged on the post-operative day 7 without any post-operative complications or need for readmission.
CONCLUSIONS: Pre-operative simulation, changes in ports for insertion of the scope and robotic first arm, continuation of the coaxial operation, and use of a powered stapler made Delta applicable for RADG. Delta can be considered as a useful reconstruction method.

INTRODUCTION

Currently, the da Vinci Si High-Definition Surgical System (da Vinci Surgical System [DVSS]; Intuitive Surgical, Inc., Sunnyvale, CA, USA), an endoscopic surgical robot, has been introduced into the surgical treatment of liver and pancreatic cancer, as well as oesophageal, stomach, and large intestinal cancer in gastrointestinal surgery.[12345] Robot-assisted gastrectomy (RAG) using the DVSS was first reported by Hashizume and Sugimachi in 2003.[6] Since then, several advancements and modifications to RAG to allow performing gastrectomy with systematic lymphadenectomy and total gastrectomy have been reported. RAG has been reported to overcome the limited manoeuvrability experienced in conventional laparoscopic surgery.[17] Therefore, the minimal invasiveness and utility of RAG, such as minimal blood loss and shorter hospital stay, are now being recognised.[789]

However, only a few reports describe the reconstruction methods employed, which is a major issue in gastrectomy.[10] At various institutions, selection of the reconstruction methods for RAG is assumed to be one of the problems in the early stages of introduction of RAG. When robot-assisted distal gastrectomy (RADG) was introduced at our hospital, delta-shaped anastomosis (Delta) – a technique most frequently performed after laparo-assisted distal gastrectomy (LADG)[1112] – was chosen as a reconstruction method after RADG. However, certain adjustments were necessary to be able to perform Delta after RADG in the same manner as after LADG. Herein, we describe the technique and tip for 4 cases which we performed.

METHODS

Patients

This study comprised four patients with clinical Stage I gastric cancer who were indicated for distal gastrectomy. The status of the patients was classified according to the Japanese Classification of Gastric Carcinoma Version 13 (translation: 2nd English version),[13] and treatment was provided as per the Gastric Cancer Treatment Guidelines for Doctors’ Ref.[14] Operative time, blood loss, anastomotic time and post-operative course were examined in all patients.

Operation methods

Setting

All operations were performed by the same operator (H. K) and the same team. The operation was performed under general anaesthesia whereas the patients were placed in the split-leg position. We monitored everything, from location of ports and robotic arms to selection of forceps and powered devices according to the report by Uyama et al.[1] Reconstruction was performed using ECHELON FLEX™ Powered ENDOPATH® Stapler 60 mm (Ethicon Endo-Surgery, LLC, Guaynabo, PR, USA).

First, a 12-mm trocar was inserted below the umbilicus (scope port). Eight-millimetre intuitive cannulas were inserted – one each in the right and left lateral hypochondriac regions (right and left upper ports). Twelve-millimetre trocars were inserted—one each at the middle of the right and left radii of a concentric circle centered at the subumbilical port and connecting the right and left hypochondriac ports (right and left lower ports). In the left lower port, an intuitive cannula was inserted in a trocar-in-trocar configuration [Figure 1a]. A 30° oblique scope was used. The DVSS patient cart was rolled in from the left cranial side of a patient. During the operation, 2 scrubbed assistants stood at each side of the patient.

Figure 1

Placement of ports. (a) During distal gastrectomy, (b) during anastomosis

Gastrectomy

During gastrectomy, the robotic first arm was inserted into the left lower port, the robotic second arm into the right upper port, and the robotic third arm into the left upper port. The right lower port was used as the assistant port. To resect the duodenum and stomach, the robotic first arm and the trocar-in-trocar cannula were removed from the left lower port, and the assistant inserted the powered stapler into the port, which was a 12-mm port. The patient cart was rolled back to retrieve the resected stomach and again rolled in after retrieval.

Reconstruction

The right lower port was used as the scope port, and the robotic first arm was inserted in a trocar-in-trocar configuration from the subumbilical port. In the same manner as in gastrectomy, the robotic second and third arms were inserted from the right and left upper ports, and the left lower port was used as the assistant port [Figure 1b].

Delta was performed as described by Kanaya et al. and Kitagami et al.[1112] The assistant inserted the cartridge fork of the powered stapler from the assistant port to the stoma of the remnant stomach [Figure 2a]. The operator inserted the anvil fork into the duodenal stoma with the gripping forceps of the robotic first and second arms [Figure 2b]. The posterior walls of the stomach and duodenum were anastomosed, and the operator held the resulting V-shaped anastomotic stoma with the forceps of the robotic first and second arms to open it [Figure 2c]. The assistant temporarily closed the entry hole using an Endo Universal™ 65° 12-mm stapler with 104.8-mm staples [Figure 3a]. Then, the assistant stapled the entry hole with the powered stapler immediately below the staples for temporary closure [Figure 3b and c].

Figure 2

Robotic Delta-shaped anastomosis 1. (a) The cartridge fork of 60 mm stapler is inserted to small incision along the edge of the remnant stomach (white arrow). (b) The anvil fork is inserted to small incision along the edge of the duodenum (arrow head). The posterior walls of both the remnant stomach and the duodenum are approximated and the stapler is fired. (c) The created V-shaped anastomosis (black arrows)

Figure 3

Robotic Delta-shaped anastomosis 2. (a) The entry hole is closed temporarily (arrows head) by firing hernia stapler (black arrow). (b) The entry hole is closed by firing 60 mm stapler under the line of temporary closures (white arrows). (c) Leakage test

RESULTS

In the four patients, the median operative time was 399 min, and the median volume of blood loss was 25 ml. While Delta was performed in the same manner in all of the patients, the median time for Delta was 16.5 min [Table 1]. After the operations, the patients were managed according to the critical path. On the day after the operation, ambulation and oral intake were started in all patients. No post-operative complication was observed, and the patients were discharged on the post-operative day 7. Thus far, all patients have been treated at the outpatient unit, and none has been readmitted.

Table 1

Operative data

DISCUSSION

In RADG, the wristed instruments, motion scaling function, tremor filtration and stereoscopic vision of DVSS enable gentle traction of fragile tissue, an approach to the dorsal side of major arteries, and performing other procedures that are considered difficult in LADG. RADG is expected to overcome the operational limitations of LADG. Lymphadenectomy has already been performed safely and precisely.[1] However, the problems of RADG include prolonged operative time, high surgical costs and lack of evidence.[789] The operative time for RADG is longer than that for LADG. We consider this a problem that should be immediately resolved so as to achieve minimal invasiveness. To shorten the learning curve and reduce operative time, standardisation of the surgical procedure is essential, and a reconstruction method that can be performed safely in a short period of time is also required as a part of the procedure.

Reconstruction after LADG is broadly classified into Billroth I and Roux-en-Y (RY) anastomosis, either of which is assumed to be applicable to RADG. Delta was reported by Kanaya et al. in 2002 to be an intracorporeal mechanical-stapled anastomosis for Billroth I reconstruction after LADG.[11] Delta has certain advantages: (1) because it can be performed completely with a scope, damage to the abdominal wall can be minimised, and (2) it can be performed in a short period. We previously reported that, compared with RY anastomosis, Delta can be performed completely laparoscopically in the short duration of 15 min and that it is a superior anastomosis method associated with a favourable post-operative course.[12] Thus, for reconstruction after RADG, we selected Delta, which could be expected to reduce operative time. Furthermore, also in terms of safety, we considered it necessary to perform Delta in the same manner as after LADG, which has proven useful.

To perform Delta in the same manner as that after LADG, it is important that the left lower port be used as the assistant port for insertion of a stapler. In RADG, the left lower port is a port for insertion of the robotic first arm, which serves as the operator's right hand, and is the most important port. To ensure that the left lower port was used as the assistant port, we did not move or add any trocars but changed the ports for insertion of the scope and the robotic first arm to those at the right side of the patient and kept the differences in the positional relationship minimal. Because reinsertion of the scope into the right lower port would reduce the distance between the duodenal stump and the scope and would provide a slightly slanted view, the operation was expected to be difficult. However, although the angle of insertion of the scope was slightly different, there was actually no difficulty in the use of forceps. We were able to perform a series of operations – such as creating a stoma and guiding a stapler – in the same manner as in LADG. This is likely attributed to the fact that (1) the wristed instruments and stereoscopic vision provided by DVSS allows for forceps to be used freely – without interference with the stapler – and (2) intuitive operations can be performed with DVSS in the coaxial mode.

In Delta, the assistant should perform a series of procedures using the stapler, from insertion and delicate positional adjustment to stapling in cooperation with the operator. In RADG, the robotic arms interfere with the surgical field, and the assistant uses the stapler through a space between them. Thus, a stapler's routine operations are sometimes difficult. In recent years, the development of electrically powered endoscopic liner staplers has advanced to provide the ability to achieve stable staple lines. We used these staplers while considering that powered staplers, which assistants can operate with simple movement, are appropriate for Delta after RADG. Moreover, because RADG does not allow face-to-face communication between the operator and the assistants, all procedures should be determined beforehand and understood by the operator and the assistants. Therefore, it is important to practice this procedure under simulated conditions, where the operator and assistant who would perform RADG performed Delta after LADG with the same stapler to be used for RADG. Thus, they may be able to perform all manoeuvres smoothly.

The number of cases of RADG is still small, and the evidence is insufficient. This is also true for reconstruction. In this study, the number of cases in which we performed Delta after RADG was small – 4 cases – and further accumulation of cases is needed.

CONCLUSIONS

Given the advantage that Delta can be performed after RADG in the same procedure as that after LADG, which has been reported to be safe and useful, we consider that Delta is a useful method for RADG.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.