Robotic Right Colectomy with Intracorporeal Anastomosis: Experience with 52 Consecutive Cases

Abstract

Background:

In laparoscopic right hemicolectomy (LRC), extracorporeal or intracorporeal (ICA) anastomosis can be performed. Several authors have suggested advantages to ICA. This study reports our transition to and our experience with robotic right colectomy (RRC) with ICA.

Materials and Methods:

From June 2009 to September 2012 we performed 58 consecutive RRCs, of which 52 were with ICA. Data were prospectively stored and retrospectively reviewed.

Results:

Twenty-eight female and 30 male patients with a mean age of 71.6±8.3 years (range, 52–89 years) were studied. Indications for surgery included adenocarcinoma (n=30), adenoma (n=20), diverticulitis (n=1), and Crohn's disease (n=1). For RRC with ICA (n=52), mean operative time (OT) was 193.2±42.2 minutes (range, 123–239 minutes). Mean estimated blood loss (EBL) was 47.8±59.5 mL (range, 5–300 mL). Mean length of hospital stay (LOS) was 3.7±3.2 days (range, 1–21 days). Mean extraction-site incision size was 4.61±0.78 cm (range, 2.5–6.5 cm). Mean lymph node harvest was 20.7±8.2 (range, 6–40). Mean specimen length was 18.9±7.2 cm (range 10–37). No intraoperative complications, conversions, or 30-day mortality occurred. Nine postoperative complications (19.1%) occurred, with one anastomotic leak (1.7%). For LRC with ICA as reported in the literature, OT ranges from 136 to 190 minutes, EBL ranges from 0 to 500 mL, median LOS ranges from 3 to 5 days, complication rates range from 6% to 15%, with ileus <22%, and conversion rates are <5%.

Conclusions:

RRC with ICA is safe and feasible. OTs and outcomes compare favorably with those published in the literature for LRC with ICA. The robot may facilitate transition to ICA, and if future studies confirm advantages of ICA, the role of RRC may gain importance.

Introduction

In laparoscopic right hemicolectomy (LRC), extracorporeal (ECA) or intracorporeal (ICA) anastomosis can be performed. There may be advantages to the construction of an ICA. Some authors have suggested that ICA results in superior postoperative outcomes and possibly lower extraction-site morbidity, such as hernias and wound infections. Hellan et al.¹ found similar outcomes with either, but shorter incisions with ICA. Bergamaschi et al.² reported that a standardized laparoscopic intracorporeal right colectomy for neoplasia of the right colon results in favorable short-term outcomes. In addition, a smaller abdominal incision for specimen extraction may have advantages in terms of cosmesis, postoperative pain, infection, return to daily activities, and incidence of incisional hernia.^3,4 Grams et al.⁵ described earlier return of bowel function, shorter length of hospital stay (LOS), and fewer complications; furthermore, performing ICA may decrease the risk of intestinal twist during extracorporeal extraction and anastomosis. However, currently, there is insufficient scientific evidence to definitively demonstrate an advantage of one technique over another.⁶

A survey published by Jamali et al.⁷ in 2008 indicates that extracorporeal creation of an ileocolic anastomosis in right colectomy remains the most commonly used modality by surgeons. It is considered as the easiest laparoscopic procedure together with sigmoidectomy. Conversely, right hemicolectomy with ICA is considered one of the most difficult procedures to perform laparoscopically and is only surpassed, in this regard, by transverse colectomy, low anterior resection, and reversal of Hartmann's procedure.⁷

Some authors have suggested that the robot may facilitate difficult or complex tasks during a procedure such as splenic flexure mobilization, pelvic dissection, or construction of an anastomosis.^8–14 In our experience, the transition from an ECA to ICA was facilitated by the robotic platform. The intuitive nature of the robot, improved surgical dexterity, and high-definition three-dimensional visualization make the switch to an ICA easier. This may lead to a higher adoption rate for ICA, which is not very commonly used in laparoscopic right colectomy today.

The aim of this study is to report our experience and outcomes performing robotic-assisted right hemicolectomy with ICA. Our standard of practice transitioned from an ECA to an ICA technique as we moved from laparoscopic to robotic-assisted right colectomy.

Materials and Methods

We analyzed the robotic-assisted right hemicolectomies performed from June 2009 to September 2012 by two board-certified colon and rectal surgeons (H.J.L. and G.P.) with extensive experience in minimally invasive surgery. Robotic techniques were introduced into our practice in June 2009. To date, our group has performed 252 robotic-assisted colectomies. We included all patients who underwent elective robot-assisted right hemicolectomy regardless of the etiology. Informed consent was obtained from all patients.

When performing laparoscopic right colectomy, our routine and customary approach was an extracorporeal technique. Early in our transition from laparoscopic to robotic surgery, we adopted an isoperistaltic, side-to-side, ICA modeled after the technique described by Rawlings et al.¹⁰

Data from 58 robotic right colectomies (RRCs) (52 intracorporeal and 6 extracorporeal) were prospectively recorded in a database and retrospectively reviewed. Data included gender, age, body mass index (BMI), estimated blood loss (EBL), operative times (OTs), total operating room time (TORT), extraction-site incision length, LOS, specimen length, anastomotic technique, conversion rates, peripostoperative complications, pathology, recurrence rates, and survival.

TORT was defined as the time elapsed from when the patient enters the room until he or she leaves the room (wheels in to wheels out). OT was defined as the time elapsed from the beginning of the incision to completion of skin closure (skin to skin). Extraction-site incision length was determined immediately after skin closure. The anesthesiologist and nursing staff recorded EBL. Conversion was defined as the use of the extraction-site wound for any portion of the dissection. Early complications were defined as those occurring during the first 30 postoperative days. Mortality was considered as death within the first 30 postoperative days regardless of the cause.

The discharge criteria were identical for both groups. Patients were discharged when tolerating a soft diet, either passing flatus or bowel movement, and satisfactory pain control on oral analgesics. Follow-up was conducted at 1 week, 6 weeks, and 1 year for the benign cases. Cancer patients were followed at 4-month intervals after their initial postoperative visits. Follow-up was accomplished by office visits, chart review, and telephone interviews when necessary.

This is an institutional review board–approved study. All the variables were collected on a database developed by A.M. using FileMaker (Santa Clara, CA) Pro^® version 11 software. Statistical analysis was performed using Microsoft (Redmond, WA) Excel^® 2010.

Robotic-assisted right colectomy technique

The patient is under general anesthesia in the supine position. Pneumoperitoneum is achieved with a Veress needle, and, in total, four ports are placed, as shown in Figure 1. We used a modification of the Crawford technique,¹⁰ but only three arms of the da Vinci^® Surgical System robot (Intuitive Surgical, Sunnyvale, CA) are used as previously described.¹⁵ The lesion is localized prior to docking the robot, using a 5-mm laparoscope. The table is then positioned in slightly reverse Trendelenburg position and tilted right side up to allow the small intestine to fall away from the midline. The robot is then docked from the patient's right side, slightly over the right shoulder. The room set-up is shown in Figure 2.

FIG. 1.

Port placement.

FIG. 2.

Room set-up.

The robotic camera is inserted through the 8.5-mm periumbilical port. The assistant surgeon uses the lateral 12-mm port to introduce laparoscopic instruments. Using the grasper and the hot shears, a medial-to-lateral dissection is carried out; the assistant surgeon grasps the ileocecal valve to put the ileocolic vascular pedicle under tension. Two windows are constructed on each side of the pedicle, and it is divided at the level of the duodenum with a vascular stapler brought in through the left-lateral 12-mm port. More recently, we have been using the EndoWrist^® One™ vessel sealer (Intuitive Surgical) for division of the ileocolic vessels at their origin. The right mesocolon is mobilized off the retroperitoneum. The ileal mesentery is divided with an energy device to a point 8–10 cm from the ileocecal valve. The mesocolic mobilization is carried up to the duodenum and the transverse mesocolon. The transverse colon and ileum are then divided with the Echelon Flex™ Endopath^® stapler (Ethicon, Somerville, NJ). The colon often remains attached to the right paracolic gutter to keep it from falling medially. If detached, the specimen is placed above the liver for later retrieval.

Next, attention is turned to constructing an isoperistaltic side-to-side anastomosis. For this purpose, the terminal ileum and the transverse colon stump are brought together. A 20-cm nonabsorbable suture on a Keith needle is used to put a stay suture through the abdominal wall to provide tension and elevate the ileum and colon. Using the hot shears, a colotomy and ileotomy are created through which the jaws of the endoscopic linear stapler are introduced to construct the common channel. The remaining defect is then closed with 2-0 polyglactin 910 (Vicryl^®; Ethicon) in two layers using robotic suturing techniques. Once complete, the stay suture is cut, and attention is again directed to the specimen to free the remaining lateral and hepatic attachments. A grasper with teeth is introduced through the 12-mm left-lateral port to hold the specimen, and the robot is undocked. The incision is then enlarged. An Alexis™ wound retractor (Applied Medical, Rancho Santa Margarita, CA) is placed to protect the skin, and the specimen is extracted. The abdominal wall and port incisions are closed in the usual fashion.

Results

Fifty-eight robotic-assisted colectomies were performed: 6 with an ECA and 52 with an ICA. Both groups were similar in demographics, BMI, indications for surgery, and comorbidities (Table 1). The ECA group had three males and three females with a mean age of 68±7.77 years (median, 69 years; range, 57–78 years). Mean BMI was 28.86±3.95 kg/m² (median, 29 kg/m²; range, 22–32 kg/m²). Indications for surgery included adenocarcinoma (n=2) and adenoma (n=4). Mean OT was 181.66±37.85 minutes (median, 180 minutes; range, 123–239 minutes). TORT was 248.66±42.23 minutes (median, 251 minutes; range, 182–304 minutes). Mean EBL was 68.33±71.67 mL (median, 35 mL; range, 20–200 mL). Mean LOS was 4.66±3.44 days (median, 3 days; range, 2–11 days). Mean extraction-site incision size was 5.37±1.35 cm (median, 5 cm; range, 4–11 cm). Mean number of lymph nodes harvested was 20±13.91 (median, 24; range, 1–38). Mean specimen length was 16.16±2.71 cm (median, 16 cm; range, 12–20 cm). No intraoperative complications, conversions, recurrence, or disease-related deaths have been observed to date. Two postoperative complications (33.33%) were recorded, but no (0%) mortality at a mean follow-up of 328 days.

Table 1.

Summary of Demographics and Characteristics of the Two Patient Groups

	Robotic-assisted right
Variable studied	Extracorporeal (n=6)	Intracorporeal (n=52)	P value
Age (years)
Mean±SD	68±7.77	71±9	.39
Median	69	72
Range	57–78	52–89
Body mass index (kg/m²)
Mean±SD	28.86±3.95	29.60±8.12	.66
Median	29	27
Range	22–32	19.47–68.89
Gender			—
Male	3	27
Female	3	25
Indication			—
Adenocarcinoma	2	30
Adenoma	4	20
Diverticulitis	0	1
Crohn's disease	0	1

SD, standard deviation.

The ICA group (27 males and 25 females) had a mean age of 71±9 years (median, 72 years; range, 52–89 years). Mean BMI was 29.60±8.12 kg/m² (median, 27 kg/m²; range, 19.47–68.89 kg/m²). Indications for surgery included adenocarcinoma (n=30), adenoma (n=20), Crohn's disease (n=1), and diverticulitis (n=1). Thirty patients had colon cancer: Stage 0 (n=3), Stage 1 (n=7), Stage 2 (n=10), Stage 3 (n=8), and Stage 4 (n=2). Mean OT was 193.21±42.21 minutes (median, 185 minutes; range, 123–336 minutes). Mean TORT was 260.71±46.53 minutes (median, 254 minutes; range, 195–419 minutes). Mean EBL was 47.78±59.49 mL (median, 20 mL; range, 5–300 mL). The mean LOS was 3.7±3.22 days (median, 3 days; range, 1–21 days). Mean extraction-site incision size was 4.61±0.78 cm (median, 4.5 cm; range, 3–6.5 cm). Mean number of lymph nodes harvested was 20.73±8.23 (median, 19; range, 6–40). Mean specimen length was 18.86±7.19 cm (median, 17 cm; range, 10–37 cm). No intraoperative complications or conversions were observed. One port-site recurrence was diagnosed in a Stage T4 patient. Nine postoperative complications (19.05%) were recorded, including one (1.9%) anastomotic leak, but no (0%) mortality at a mean follow-up of 130 days. Results are summarized in Table 2.

Table 2.

Summary of Results

	Robotic-assisted right
Variable studied	Extracorporeal (n=6)	Intracorporeal (n=52)	P value
Surgical time (minutes)
Mean±SD	181.66±37.85	193.21±42.21	.52
Median	180	185
Range	123–239	123–336
Total operating room time (minutes)
Mean±SD	248.66±42.23	260.71±46.53	.58
Median	251	254
Range	182–304	195–419
Estimated blood loss (mL)
Mean±SD	68.33±71.67	47.78±59.49	.56
Median	35	20
Range	20–200	5–300
Length of stay (days)
Mean±SD	4.66±3.44	3.7±3.22	.50
Median	3	3
Range	2–11	1–21
Extraction-site length (cm)
Mean±SD	5.37±1.35	4.61±0.78	.008
Median	5	4.5
Range	4–11	3–6.5
Specimen length (cm)
Mean±SD	16.16±2.71	18.86±7.19	.08
Median	16	17
Range	10–20	10–37
Number of lymph nodes
Mean±SD	20±13.91	20.73±8.23	.88
Median	24	19
Range	1–38	06–40
Conversion to open surgery	0 (0%)	0 (0%)	—

SD, standard deviation.

Discussion

In their systematic review of the literature, Antoniou et al.¹⁶ identified 39 series that reported a total of 210 RRCs. The mean operative time for these cases was 167 minutes (range, 152–228 minutes). These series included right colectomies with both ECA and ICA techniques. Our 3-year experience suggest that robotic-assisted right colectomy is safe, feasible, and reproducible for the elective management of right colon pathology, and outcomes, including OT, EBL, conversion rate, and complications, compare favorably with those published in the literature for laparoscopic right colectomy and RRC. Mean operative time was 181.66 minutes for ECA (n=6) and 193.21 minutes for ICA (n=52). Comparison of these results with those reported in the literature is difficult because there are variations in surgical techniques and differences in OT reporting. However, the mean OT in studies of RRC with ICA varies between 189 and 270 minutes.^9,10,15–18 The mean OT in studies of laparoscopic surgery for right hemicolectomies with ICA varies between 136 and 190 minutes.^1,5,19,20 As we have shown, OTs for RRC are similar to those for laparoscopic right colectomy. It is well known that robot docking and interchange of robotic instruments increase OTs. We should also take into consideration that OTs for RRC are based on relatively few procedures early in our robotic experience. At present, comparisons with laparoscopic right colectomy are unfair because laparoscopic colectomy has been around since the early 1990s. We are optimistic that the RRC technique can still be streamlined and refined.

Some authors have suggested that the robot may facilitate difficult or complex tasks during a procedure such as splenic flexure mobilization, pelvic dissection, and construction of an anastomosis.^13–16 We believe that the intuitive nature of the robot and the improved surgical dexterity facilitate the transition from an ECA technique to an ICA. In the first six RRCs, the anastomosis was constructed extracorporeally, as had been the routine practice for LRCs in the authors' previous experience. However, all subsequent RRCs were performed with an ICA. In other words, we adopted a completely intracorporeal technique (after our initial six RRCs) early in our learning curve. The transition to ICA was subjectively experienced as a natural progression that had not occurred for the authors in 12 years (H.J.L.) and 19 years (G.P.) of prior laparoscopic colectomy experience.¹⁵

There may be advantages to the construction of an ICA. In fact, some studies have suggested that ICA results in superior postoperative outcomes and possibly lower extraction-site morbidity such as hernia and wound infection.^1,5,15,20 For example, there is probably less trauma, traction, and tension applied to the ileum, colon, and mesentery during an ICA technique. After intracorporeal transection, the terminal ileum and transverse colon almost always reach without tension for anastomosis. Because the specimen is completely detached, it can be brought out through any extraction site. Less mobilization of the transverse colon is necessary because it does not have to reach the abdominal wall for anastomosis as with ECA and can simply lie in its normal anatomic position after transection. Conversely, when an ECA is performed, trauma and stretching of the bowels and their mesentery can occur during externalization. One more advantage of the ICA is that bowel orientation is not lost, and “twisting” of the mesentery is avoided. On the other hand, the creation of an ECA is often partially blind, especially in the obese patient.^2,15,17 These differences may translate into less postoperative ileus and fewer complications. In theory, this could favorably impact on LOS and leak rates. Larger comparative studies or randomized control trials are needed to determine whether or not ICA has advantages over ECA in minimally invasive right colectomy. A recent systematic review and meta-analysis failed to resolve the controversy because of the lack of evidence and insufficient data in the current published literature.⁶

Another advantage of the ICA technique (which demands the total intracorporeal resection of the specimen) is that it allows the surgeon to choose where to place the incision for extraction. Recent data have shown that keeping the extraction site off the midline results in decreased risk of hernia. Samia et al.²¹ showed an almost twofold increase in risk of incisional hernia when the extraction site was placed in the midline. By using an ICA technique the surgeon can choose an extraction site off the midline.

Some studies have suggested that blood loss is less with RRC. However, DeSouza et al.¹⁸ in their study comparing 135 laparoscopic with 40 RRCs found no difference in blood loss. In our own study, EBL for the robotic group was significantly less when compared with the laparoscopic group.¹⁵ Although we would like to attribute the lower blood loss to a more precise dissection achieved with the robot, blood loss was a poorly controlled parameter. Furthermore, as with incision length, differences may not have any clinical significance. Further study will be needed to clarify this issue.

Conversion to open or to laparoscopy in our experience was 0% (n=52). This result is comparable to what we reported in our previous experience¹⁵ and also to what was reported by D'Annibale et al.⁹ (conversion rate=1.1%) in patients who underwent robotic-assisted right colectomy with ICA for cancer.

The American Joint Committee on Cancer and the College of American Pathologists recommend evaluation of a minimum of 12 lymph nodes to guarantee a sufficient oncological radicality.^22,23 Bergamaschi et al.² reported in their laparoscopic case series a median of 29 lymph nodes harvested using the intracorporeal approach. This is higher than the previously recommended minimum number of 12. In our experience, the mean number of harvested lymph nodes was 20.73, and this result is in line with those reported in larger series on robotic right hemicolectomy, which vary from 17 to 19.^9,18,24 Length of the specimen is directly related to the number of lymph nodes harvested, and our mean specimen length was 18.86±7.19 cm for the ICA approach and is comparable to laparoscopic colectomy data.¹⁸ Absence of an adequate follow-up period to evaluate recurrence and long-term survival represents a limitation of this study even if this was not the purpose of our analysis.¹⁵

A mean LOS of 3.7 days (n=52) is similar to that in our previous report of 3.6 days (n=22).¹⁵ In addition, when compared with recent reports for either laparoscopic or RRC with ICA, our data compare favorably.^{7,9,18,25–27} However, our data only show similar LOS for LRC versus RRC.

Overall, our postoperative complication rate was 16.6% for RRC with ICA, which is similar to rates published in the literature.¹⁸ Furthermore, no intraoperative complications occurred in our patients. As mentioned, a recent meta-analysis by Cirocchi et al.⁶ did not find any significant difference in anastomotic leakage rate between ICA and ECA in LRC. In our study, one leak (1.92%) was reported in the ICA group. This result is consistent with our own previous experience and with other studies on robotic ileocolic ICA, which reported percentages of anastomotic leakages that vary between 0% and 5.9%.^9,10,15,17

A cost analysis is beyond the scope of this article. At present, it appears that RRC is more expensive than laparoscopic. However, how much more is widely debated and influenced by several factors. A true cost analysis would involve amortizing capital costs and an analysis of the purchasing practices of different institutions and the specific contracts with industry. Furthermore, surgeon preferences and techniques vary and influence the cost of each case. For purposes of discussion here, we assume that large capital costs, including purchase of laparoscopic towers, monitors, robot, and basic equipment, are removed from the equation. If we just compare the cost of robotic disposable devices (specifically, the robotic hook, bipolar fenestrated grasper, EndoWrist One vessel sealer, and EndoWrist stapler 45) versus laparoscopic disposables (energy device, endoscopic stapler, linear stapler 75, and reloadable stapler 60), the estimated range is from U.S. $400 to $1000 difference in favor of laparoscopic. In a recent randomized clinical trial, Park et al.²⁸ concluded that, although feasible, RRC did not provide benefit to justify the greater cost. The authors did state the limitations of the study included few patients and a single surgeon with greater laparoscopic experience. They also stated that future developments in robotic technology would prompt re-evaluation of the use of robotics in colon resection.²⁸

We share the opinion that the dissection with the robot is precise. In fact, blunt dissection and excessive tension on tissues are dangerous with the robot. This, in turn, promotes principles of sharp dissection and maintaining proper planes. Superior visualization, a stable platform, and articulating instruments all contribute to this advantage. This could have clinical relevance if we think of how laparoscopic colorectal surgery proved to be less traumatic than open surgery. Some authors believe that minimally invasive techniques are less traumatic and less immunosuppressive, are associated with less ileus, and result in quicker recovery.^29,30 However, the true advantage of robotics may lie in its ability to simplify complex tasks, and robotics may facilitate the adoption of minimally invasive techniques and ICA in right colectomy. Finally, if future studies confirm that ICA is advantageous, the role of RRC may gain importance.

Future multi-institutional, randomized, controlled studies are needed to determine whether RRC can provide better outcomes than LRC and justify costs. More data on ECA versus ICA are also needed. Comparative studies may help define the role of robotics in right colectomy in the near future.

Conclusions

• For right colectomy, robotic surgery is feasible and appears to be at least as safe as laparoscopic surgery.

• Operative times for RRC with ICA are comparable to those for LRC with ICA.

• ICA can be performed safely with the robot.

• If future studies confirm advantages of ICA, the role of RRC may gain importance.

Footnotes

Disclosure Statement

H.J.L. is a proctor/speaker for Intuitive Surgical and also owns stock in Intuitive Surgical. G.P. is a consultant/speaker for Ethicon Endosurgery, Inc. A.M., A.B., and B.R. declare no competing financial interests exist.

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