Single-Incision Laparoscopic Sleeve Gastrectomy Versus Multiport Laparoscopic Sleeve Gastrectomy: Analysis of 80 Cases in a Single Center

Abstract

Background:

Through efficacy and improved safety, multiport laparoscopic sleeve gastrectomy (LAPS-G) has emerged as an important and broadly available treatment option for people with severe and complex obesity. Because a single-incision laparoscopic sleeve gastrectomy (SILS-G) would be less invasive, we applied this novel surgical technique for a selected number of patients enrolled into our minimally invasive bariatric program.

Subjects and Methods:

A retrospective review of prospectively collected data from 80 morbidly obese patients who qualified for SILS-G or LAPS-G was performed from January 2011 to May 2012.

Results:

SILS-G and LAPS-G were performed in 40 patients, respectively. All patients were female. Mean age was 41 (range, 19–73) years (SILS-G, 37 [19–62] years; LAPS-G, 43 [24–73] years; P=not significant). Preoperative body mass index was 40.8 (35.1–45.0) kg/m² in the SILS-G group and 43.8 (35.0–47.8) kg/m² in the LAPS-G group (P=not significant). Total operative time was significantly lower in the SILS-G group (85±21 minutes) compared with the LAPS-G group (97±26 minutes) (P<.05). Median percentage excess weight loss was comparable in both groups (SILS-G, 57.2%; LAPS-G, 53.7%) at 6.6 months after surgery. Mean hospital stay was 5 days (SILS-G, 5 [4–24] days; LAPS-G, 6 [4–14] days; P=not significant). Complication rates were low in both groups: leakage, 2.5% in SILS-G and 0% in LAPS-G; bleeding, 2.5% in SILS-G and 2.5% in LAPS-G; and trocar-site hernia, 0% in both groups. Patients operated on with single-incision laparoscopy had a significantly better cosmetic outcome as assessed by a scar satisfaction assessment questionnaire (P<.01).

Conclusions:

SILS-G is a feasible and safe operative procedure that leads to a significant reduction of total operative time compared with a multiport access procedure. Further potential benefits associated with single-incision laparoscopic surgery remain to be investigated objectively.

Introduction

In the last decades, bariatric surgery has emerged as an important and broadly available treatment option for severely obese patients in whom conservative treatment strategies have proven ineffective. Although prevalently renowned as an additional tool to life-style changes and potential drug therapies, bariatric surgery has inevitably provided us with the most efficient weight loss solution for obese individuals.¹ As a result of this popularity in gastrointestinal surgical interventions, a great interest in the development of novel surgical devices and less invasive procedures has emerged. The basic motto behind this evolution was deliver more through less.²

Accordingly, bariatric surgery has evolved from the era of large incisions used in open surgery and multiple small incisions in laparoscopy to minimally invasive single-incision techniques. To date there is no perfect bariatric procedure. Patient selections are based on local availability, the individual balance of risks and benefits, and ultimately patient choice. Established procedures include the Roux-en-Y gastric bypass, sleeve gastrectomy, and adjustable gastric banding operation, which account for more than 95% of all bariatric surgical procedures worldwide.³ Purely malabsorbtive procedures, such as biliopancreatic diversion and its variant the duodenal switch, play minor roles as primary procedures but still remain an alternative option for patients who may not respond adequately to less radical procedures.

Although laparoscopic sleeve gastrectomy is relatively new in the field of bariatric surgery, it has become the popular preferred method among bariatric surgeons because of its technical simplicity compared with the Roux-en-Y gastric bypass operation and other malabsorbtive procedures.⁴ Likewise, it is well accepted among patients because gastrointestinal continuity is maintained and no foreign device needs to be implanted into the human body, which bears the risk of infection and migration.⁵ Usually laparoscopic sleeve gastrectomy requires four or five skin incisions positioned across the upper abdomen to place laparoscopic trocars for surgery.^6–8

Since its first inception into gynecology,⁹ single-incision laparoscopic surgery (SILS) has been a dynamic field experiencing giant leaps in technique and instrumental design. This has recently facilitated its expansion from general surgical procedures like appendectomy, cholecystectomy, and splenectomy to more complex bariatric operations like sleeve gastrectomies and implantation of adjustable gastric bandings.^10–14 More recently Saber et al.¹⁵ and Huang et al.¹⁶ strikingly reported the first single-access Roux-en-Y gastric bypass. Single-incision laparoscopy literally consists of one single umbilical incision as the only entry for all surgical instruments to obtain an excellent cosmetic outcome with the wound finally completely hidden in the umbilicus.¹⁷ Further key benefits of this novel surgical technique may comprise a significant reduction of postoperative pain and a shorter hospital stays while having complications rates comparable to those of conventionally accepted procedures.

At Innsbruck Medical University (Innsbruck, Austria) we have been performing both the conventional multiport and the single-incision sleeve gastrectomy from 2008. This study was designed to evaluate the feasibility and identify possible limitations of single-incision laparoscopic sleeve gastrectomy (SILS-G) compared with the conventional multiport variant.

Subjects and Methods

Study design

Prospectively collected data from 80 female patients who underwent sleeve gastrectomy from January 2011 to May 2012 were analyzed. Multiport laparoscopic sleeve gastrectomy (LAPS-G) and SILS-G were performed in 40 patients each. The study was approved by the institutional review board, and informed consent pertaining to both procedures was obtained from all patients. The same surgical team consisting of one senior surgeon and one surgical resident performed all operations. Prior surgery anthropometric parameters were evaluated, and all patients were subjected to a routine gastroduodenoscopy, esophageal manometry, and 24-hour pH monitoring. No liquid diet was supplied to our patients preoperatively.

Exclusion criteria from this study were as follows: (1) previous bariatric surgery or abdominal surgery with excessive scarring; (2) age less than 18 years or more than 75 years; and (3) patients with a body mass index (BMI) of less than 35 kg/m² or more than 50 kg/m².

Prior to surgery patients received 2.2 g of amoxicillin for infectious prophylaxis. Intra- and postoperative pain therapy consisted of piritramid (0.1 mg/kg i.v.) given immediately after surgery and paracetamol (1 g i.v.) as well as metamizol (1000 mg i.v.) administered every 8 hours after surgery. During the entire hospitalization period, prophylaxis for deep vein thrombosis comprised daily injections of low-molecular-weight heparin (starting 12 hours prior to surgery) and administration of deep vein thrombosis stockings.

Postoperative outcomes in terms of percentage excess weight loss (%EWL), resolution of comorbidities, and complication rates were compared at a follow-up of 6.6 months. The %EWL was defined as ([operative weight – follow-up weight]/operative excess weight)×100.¹⁸

At 3 months postsurgery patients were interviewed and assessed using our patient scar satisfaction assessment questionnaire. Regarding scar satisfaction, patients could give five possible responses: excellent=1, good=2, fair=3, acceptable=4, and poor=5. A lower score indicated a favorable outcome.

Statistical analysis

Results are expressed as mean (range) values. Statistical analysis was performed using the Mann–Whitney U test to compare the median value of two groups (Prism version 5.0 software; GraphPad Software, La Jolla, CA). A P value of <.05 was considered to be statistically significant.

Surgical technique of SILS-G

Patients were placed on the operation table in the medium lithotomy position, allowing the surgeon to stand between the split legs. The assistant was positioned at the left side of the patient. With the patient under general anesthesia, a 4-cm vertical transumbilical incision was made, and the abdomen was entered via an open technique. Either a GelPOINT^® (Applied Medical, Rancho Santa Margarita, CA) advanced access platform (n=10) with one 12-mm and three 5-mm GelPOINT trocars or the OCTO-Port^® (AFS Medical, Austria) (n=30) was used. Pneumoperitoneum was achieved with carbon dioxide insufflation, maintaining a continuous intraabdominal pressure of 14 mm Hg. For SILS we used a 5-mm, 30° optic (Stryker Endoscopy, Montreux, Switzerland) and 5-mm Ligasure^® (Valleylab; Covidien, Mansfield, MA) as well as 5-mm flexible graspers (Karl Storz, Tuttlingen, Germany). In the steep reverse Trendelenburg position the sleeve gastrectomy was started 6 cm proximal to the pylorus by dissection of the gastrocolic as well as the gastrosplenic ligament from the greater curvature of the stomach. By lifting the stomach the left lobe of the liver was automatically pulled up, and posterior adhesions to the pancreas were carefully separated, while care was taken to avoid injury to the spleen. Finally, the left crus of the diaphragm and the angle of His were completely dissected free to avoid leaving a posterior pouch when generating the sleeve in this region. No extra retraction of the left lobe of the liver was necessary in our patients, and no preoperative liquid diet to reduce liver volume was applied.

In a next step a 36 French bougie was inserted orally into the stomach and placed against the lesser curvature. The gastric sleeve was subsequently prepared using a long Echelon Flex^®, 60-mm, linear stapler (Ethicon Endo-Surgery, a Johnson and Johnson Company, Cincinnati, OH) following the edge of the calibrating bougie. A golden cartridge (open staple height, 3.8 mm; closed staple height, 1.8 mm) was used two times starting 6 cm proximal to the pylorus followed by a blue cartridge (open staple height, 3.5 mm; closed staple height, 1.5 mm). Between the closure of the stapler and its firing a 30–45-second interval was observed in every case. Sequential firing of the stapler completed the transection at the gastroesophageal junction. After the resection was completed, the staple line was inspected carefully for any malformation of the staples. Reinforcement of the staple line, and in particular of junctions of each staple firing, was performed regularly by application of endosurgical titanium clips (Ligamax^®; Ethicon). Finally, the transected stomach was removed directly through the port without using any specimen collection bag, and the abdomen was closed with 0/0 polyglactin 910 (Vicryl™; Ethicon) interrupted sutures. All patients left the operation room without a nasogastric tube.

An upper gastrointestinal series with diatrizoate meglumine and diatrizoate sodium (Gastrografin^®; Bracco Diagnostics Inc., Princeton, NJ) was performed on postoperative Day 1, and if it was negative the patient was put on liquid diet consumption for 1 day. Because of the Austrian insurance and clearing system patients were discharged as early as postoperative Day 4 once they were able to maintain hydration and manage pain with oral analgetics. A routine follow-up with attention to electrolyte and vitamin levels was recommended at 3, 6, and 12 months after surgery, and patients were invited to fill out a scar satisfaction assessment questionnaire at 3 months after surgery.

Surgical technique for LAPS-G

The multiport sleeve gatrectomy was performed as described by Moy et al.⁶ with the patient in the supine position on a split-leg operating table. In brief, a 12-mm trocar (Autosuture™; Covidien) was placed approximately 5 cm proximal to the umbilicus with an open entry, and pneumoperitoneum was achieved with carbon dioxide. Three additional 12-mm trocars were placed under direct vision into the right and left middle epigastrium and one in the right upper quadrant for liver retraction, which was carried out using a straight liver retractor. All further surgical steps were essentially the same as described for the single-incision technique. Once the stomach was transected, the remnant was put into a specimen collection bag and removed. Again, reinforcement of the stapler line was achieved with endosurgical titanium clips (Ligamax). Finally, all incisions were closed with 0/0 Vicryl sutures. In our first 36 cases of multiport sleeve gastrectomy, a 15-Robinson drain was inserted and placed into the left upper abdomen without brushing the staple line.

Results

Following evaluation of anthropometric parameters, demographics, and comorbidities, no statistical differences were observed between the two groups (Table 1).

Table 1.

Demographics of the Two Groups of Laparoscopic Sleeve Gastrectomy Patients

Demographic	SILS-G (n=40)	LAPS-G (n=40)
Age (years) [mean (range)]	37 (19–62)	43 (24–73)
BMI (kg/m²) [mean (range)]	40.8 (35.1–45.0)	43.8 (35.0–47.8)
Drainage [n (%)]^a	0 (0%)	36 (90%)
Operation time (minutes) (mean±SD)^a	84.8±21.3	97.4±26.0
Length of hospital stay (days) [mean (range)]	5 (4–24)	6 (4–14)
Comorbidities [n (%)]
Hyperlipidemia	3 (7.5%)	4 (10%)
Hypertension	4 (10%)	2 (5%)
Diabetes mellitus	1 (2.5%)	2 (5%)
Cosmetic outcome [mean (range)]^b,c	1.1 (1–2)	2.0 (1–3)

P<.05.

P<.01.

On a scale of 1–5.

BMI, body mass index; LAPS-G, multiport laparoscopic sleeve gastrectomy; SD, standard deviation; SILS-G, single-incision laparoscopic sleeve gastrectomy.

In total, 80 female patients (SILS-G, n=40; LAPS-G, n=40) underwent sleeve gastrectomy at our institution. The mean age was 41 (range, 19–73) years, and mean preoperative BMI was 42.5 (range, 35.0–47.8) kg/m² (SILS-G, 40.8 [35.1–45.0] kg/m²; LAPS-G, 43.8 [35.0–47.8] kg/m²; P=not significant). The mean operative time was significantly shorter in the SILS-G group compared with the LAPS-G group (SILS-G, 84.8±21.3 minutes; LAPS-G, 97.4±26.0 minutes; P<.05). No conversion to standard laparoscopic surgery or open surgery was needed. No intraoperative and postoperative deaths occurred.

Overall, we had three postoperative surgical complications (3.75%) (Table 2). One patient in the SILS-G group developed a stapler line leakage near the esophagogastric junction, which was diagnosed at postoperative Day 4. It is interesting that the postoperative upper gastrointestinal x-ray series performed with Gastrografin was negative on postoperative Days 1 and 4 for this patient, and the leak was solely diagnosed by clinical symptoms (fever, 38.5°C; tachycardia, 100/minute; pain visual analog scale, 5). The patient underwent relaparotomy and abdominal lavage, the leak was oversewn with (polydioxanone) monofilament synthetic absorbable suture (PDS™; Ethicon) 5.0 running sutures, two drains were positioned close to the leak, and an endoscopic stent was placed. The further course was uneventful, and the patient could be discharged on postoperative Day 24 without further complications. Two postoperative bleedings (2.5%), one within the SILS-G group (2.5%) and another one within the LAPS-G group (2.5%), which were also solely detected by clinical symptoms (tachycardia, 100/minute; low blood pressure <100/60 mm Hg), were resolved by single-incision and multiport relaparoscopy and endosurgical clipping.

Table 2.

Postoperative Complications

	n (%)
Complication	SILS-G (n=40)	LAPS-G (n=40)
Leakage	1 (2.5%)	0 (0%)
Bleeding	1 (2.5%)	1 (2.5%)
Reflux	2 (5%)	3 (7.5%)
Trocar-site hernia	0 (0%)	0 (0%)

LAPS-G, multiport laparoscopic sleeve gastrectomy; SILS-G, single-incision laparoscopic sleeve gastrectomy.

The mean postoperative hospital stay was similar in both groups (SILS-G, 5 [4–24] days; LAPS-G, 6 [4–14] days; P=not significant).

At 3 months of follow-up all patients were interviewed and assessed using our patient scar satisfaction assessment questionnaire. As expected, the SILS-G group appreciated their cosmetic outcome, resulting in a significant better score compared with the LAPS-G, which which still indicated positive results (SILS-G score, 1.1 [1–2]; LAPS-G score, 2.0 [1–3]; P<.01). No difference in terms of scar satisfaction was observed between LAPS-G patients who received drains or not.

Regarding postoperative %EWL, patients were followed up 6.6 months after surgery. Both groups had distinct reductions in excess weight (SILS-G %EWL, 57.2%; LAPS-G %EWL, 53.7%; P=not significant). No postoperative stenosis or fistulas were observed in our patients, and no trocar-site hernias were reported so far. No improvements in comorbidities (hyperlipidemia, hypertension, and diabetes mellitus [data not shown]) were detected in the short-term follow-up; however, incidences were low right from the start in our selected group of patients. To date all patients are satisfied with their weight loss and cosmetic outcome.

Discussion

Although still considered as an “experimental definitive bariatric procedure” (as stated by the American Society for Metabolic and Bariatric Surgery), laparoscopic sleeve gastrectomy is emerging as an important and broadly available treatment option for severely obese patients who have not responded to other therapy.¹⁹ The mechanism of action and the improvement in comorbidities seen after sleeve gastrectomy might be related to a plethora of factors, including gastric restriction and its related neurohumoral changes.²⁰

Laparoscopy has numerous advantages compared with open surgery, and currently the interest of some bariatric surgeons, open to novel surgical techniques, focuses on even less-invasive operative procedures such as SILS. Using only one skin incision for the introduction of numerous surgical devices bears several benefits for the patient, including better cosmesis, less pain, and hence lower need for postoperative analgesia as well as shorter hospitalization time.^13,21,22 However, SILS also demands a critical learning curve because the loss of triangulation and frequent clashing of the instruments increase the difficulty of the surgical procedure.²³

In the present study we describe our experience with SILS applied to sleeve gastrectomy for morbidly obese patients. Besides a smaller series of 8 patients published by Gentileschi et al.,⁵ this is one of the first studies describing a single transumbilical surgical access for the introduction of all surgical instruments without the need for further abdominal incisions for liver retraction. However, as described earlier,²⁴ we suggest that without any kind of liver retraction the use of SILS in bariatric surgery might at this stage only be considered for patients with a BMI of less than 45 kg/m², and if stringently needed a liver retractor or liver suspension sutures should additionally be called into service.⁴

It is interesting that our data demonstrate for the first time that, in contrast to other studies,² SILS leads to a significant reduction in total operation time. This might be related to the fact that the insertion of the trocar used in our study is very straightforward and facilitates a feasible, safe, and fast application of the pneumoperitoneum. After an initial learning curve the specific technically demanding steps of the procedure can easily be carried out without significant time loss. Finally, the closure of one slightly larger incision seems to be less time consuming than closing multiple smaller incisions, which might be more difficult to access in obese patients.

Regarding weight loss, as expected, no differences were observed between our SILS-G (57.2%) and LAPS-G (53.7%) groups within the first 6.6 months; once again, the sleeve gastrectomy seems to be equally effective as the Roux-en-Y gastric bypass procedure in the short-term follow-up. In fact, the sleeve gastrectomy even seems to be more feasible because the total operation time is shorter and the technically challenging part of the operation is substantially easier to perform, which results in lower mortality rates.²⁵ If ineffective, the sleeve gastrectomy can easily be extended to a Roux-en-Y gastric bypass or a duodenal switch procedure.

Regarding peri- and postoperative complications, we had a very low incidence of leaks, hemorrhages, and trocar-site hernias. As described in the literature as well as in our cases, most leaks are detected clinically and become noticeable by patient-related symptoms like fever, tachycardia, pain, and leukocytosis.²⁶ In case of leakage—from our own experience—we strongly recommend an early relaparoscopy or relaparotomy if technically unavoidable, abdominal lavage, drainage, and placement of an esophageal stent, if applicable.

We furthermore assume that suture line reinforcement reduces the incidence of peri- and postoperative bleeding and may reduce the risk of staple line leakage.^6,27 We use different staple heights (1.8 mm at the antrum of the stomach and 1.5 mm at the fundus of the stomach) because we believe that this strategy provides optimal tissue approximation throughout the variable wall thickness of the stomach.

It is interesting that no early trocar-site hernias were observed in our study population. Although it seems intuitive that trocar-site hernias might be more frequent at the umbilicus after SILS in morbidly obese patients, no evidence has been reported on differences of single-port and conventional multiport laparoscopy. Many authors might consider higher BMI a risk factor for trocar-site hernias; however, to date only one study by Uslu et al.²⁸ found a BMI of 28 kg/m² or higher to be a significant risk factor for postoperative trocar-site hernia development. In contrast, other studies did not reveal any association between trocar-site hernias and BMI.²⁹

This study has several limitations. First, it is a retrospective analysis of a relatively small number of patients. However, our intention was to evaluate feasibility and safety of this novel single-incision surgical approach, which could in fact be demonstrated without any limitations. Following these results we intend to extend this study into a prospective randomized controlled trial, comparing SISL-G versus LAPS-G in a larger cohort of patients for a longer follow-up period.

Second, patients included into our study were all female with a “relatively low” BMI. Admittedly, female patients are technically better candidates for this kind of minimally invasive bariatric procedure because of their shorter body height and smaller left liver lobe. In their 2008 case report Reavis et al.²⁴ already reported that SILS might be limited only to patients with lower BMI. Even though the entire surgery is performed without any countertraction, loss of triangulation, and frequent clashing of the instruments, which are all inserted through a very small incision, a novel armamentarium of devices like the GelPOINT advanced access platform, the OCTO-Port, and flexible graspers have been developed to facilitate better intraabdominal access and maneuverability. However, we have to admit that to date the benefits of SILS-G may not extend to extremely tall male patients with a BMI over 50 kg/m².

Another noteworthy limitation to this study might result from the fact that the advantage of superior cosmesis following 3 months after SILS-G underlies a highly subjective and interindividual judgment and is therefore difficult to objectify. Furthermore, laparoscopic scars might fade significantly over time and be barely noticeable after 1 year.

The success of bariatric surgery bears a bright future for surgeons and industry in the discovery and innovation of new techniques and devices. Sleeve gastrectomy is continuously evolving, and specific refinements to sleeve size, the extent of antral removal, and technical changes to minimize staple line complications are aiming to further improve its efficacy and safety.³⁰ According to our point of view, SILS-G is a safe, feasible, and effective bariatric procedure, which currently can be applied with great success to a selected group of morbidly obese patients.

Footnotes

Disclosure Statement

No competing financial interests exist.

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