A Delphi consensus on the surgical technique of laparoscopic sleeve gastrectomy: An obesity and metabolic surgery society of India initiative

Aparna Govil Bhasker; Om Tantia; Manish Khaitan; Randeep Wadhawan; KS Kular; Sarfaraz Jalil Baig; Sumeet Shah; Vivek Bindal; Ashish Vashishtha; Atul N. C. Peters; Deep Goel; Mahendra Narwaria; Manish Baijal; Nandakishore Dukkipati; Pradeep Chowbey; Rajesh Bhojwani; Ramen Goel; Sandeep Aggarwal; Sanjay Borude; Sanjay Patolia; Shashank Shah; Shrihari Dhorepatil; Sreejoy Patnaik; Sudhir Kalhan; Surendra Ugale; Praveen Raj Palanivelu

doi:10.4103/jbs.jbs_7_23

ORIGINAL ARTICLE

Year : 2023 | Volume : 2 | Issue : 2 | Page : 79-84

A Delphi consensus on the surgical technique of laparoscopic sleeve gastrectomy: An obesity and metabolic surgery society of India initiative

Aparna Govil Bhasker¹, Om Tantia², Manish Khaitan³, Randeep Wadhawan⁴, KS Kular⁵, Sarfaraz Jalil Baig⁶, Sumeet Shah⁷, Vivek Bindal⁸, Ashish Vashishtha⁹, Atul N. C. Peters¹⁰, Deep Goel¹¹, Mahendra Narwaria¹², Manish Baijal¹³, Nandakishore Dukkipati¹⁴, Pradeep Chowbey¹⁵, Rajesh Bhojwani¹⁶, Ramen Goel¹⁷, Sandeep Aggarwal¹⁸, Sanjay Borude¹⁹, Sanjay Patolia²⁰, Shashank Shah²¹, Shrihari Dhorepatil²², Sreejoy Patnaik²³, Sudhir Kalhan²⁴, Surendra Ugale²⁵, Praveen Raj Palanivelu²⁶
¹ Saifee Hospital, Mumbai, India
² ILS Hospital, Kolkata, India
³ KD Hospital, Ahmedabad, India
⁴ Manipal Hospital, New Delhi, India
⁵ Kular Jospital, Bija, Punjab, India
⁶ Belle Vue Hospital, Kolkata, West Bengal, India
⁷ PSRI Hospital, Delhi, India
⁸ Max Hospital, Delhi, India
⁹ Department of General Surgery & Robotics, Bariatric & Robotic Surgeon, Max Superspeciality Hospital, Saket, New Delhi, India
¹⁰ Max Smart Superspecialty Hospital, Saket, Delhi, India
¹¹ Max-BLK Super Specialty Hospital, New Delhi, India
¹² Asian Bariatric Pvt. Ltd, Ahmedabad, Gujarat, India
¹³ Max Institute of Laparoscopic, Endoscopic and Bariatric Surgery, Hyderabad, India
¹⁴ LivLife Hospital, Hyderabad, India
¹⁵ Max Healthcare, New Delhi, India
¹⁶ Santokba Durlabhji Memorial Hospital, Jaipur, Rajasthan, India
¹⁷ Wockhardt Hospital, Mumbai, India
¹⁸ All India Institute of Medical Sciences, New Delhi, India
¹⁹ Breach Candy Hospital, Mumbai, India
²⁰ Asian Bariatrics, Ahmedabad, India
²¹ Laparo-obeso Center, Pune, India
²² Shree Hospital, Pune, Maharashtra, India
²³ Shanti Memorial Hospital, Cuttack, India
²⁴ Gangaram Hospital, Delhi, India
²⁵ Kirloskar Hospital, Hyderabad, India
²⁶ Gem Hospital, Coimbatore, India

Date of Submission	13-Apr-2023
Date of Acceptance	01-Jun-2023
Date of Web Publication	28-Jul-2023

Correspondence Address:
Aparna Govil Bhasker
Saifee Hospital, Mumbai, Maharashtra
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jbs.jbs_7_23

Abstract

Introduction: Laparoscopic sleeve gastrectomy (LSG) is the commonest bariatric operation being performed in India and worldwide. There are many technical variations that are being practiced. This Delphi consensus was an Obesity and Metabolic Surgery Society of India (OSSI) initiative to standardize the surgical technique of LSG. Methods: Twenty bariatric surgeons were selected as experts based on their years of experience in LSG, overall patient volumes, publications, and the recommendations of the executive committee of OSSI, to vote on 26 statements regarding the surgical steps of LSG. The minimum cutoff for consensus was taken as 70%. Results: The committee achieved a consensus on 19 out of 26 statements in the first round. One question was sent for reconsideration and 3 were resent after modification. Finally, consensus was reached on 22 statements. The consensus was reached regarding the use of preoperative upper gastrointestinal endoscopy. 85.7% agreed on an antral length of 3–5 cm. 85.7% were in favor of dissecting the left crus of the diaphragm completely and 100% agreed on Roux-en y gastric bypass to be the procedure of choice in the presence of medically refractory gastroesophageal reflux disease with hiatus hernia. Most experts agreed that a calibration tube must be used during LSG and the recommended size was between 36 and 40 Fr. Ninety-five percent agreed that care must be taken to avoid narrowing at the incisura and also to stay away from the angle of His. 71.4% did not recommend any kind of staple line reinforcement and 71.4% recommended a postoperative leak test. Conclusion: This Delphi consensus is a step toward improving the quality of surgical outcomes of LSG in India. This document has attempted to establish technical specifications of performing LSG. This will in turn help to maximize the reliability, standardization, and safety of the procedure until more robust studies are published.

Keywords: Antral length, bougie size, Delphi consensus, gastroesophageal reflux disease, sleeve gastrectomy, techniques

How to cite this article:
Bhasker AG, Tantia O, Khaitan M, Wadhawan R, Kular K S, Baig SJ, Shah S, Bindal V, Vashishtha A, Peters AN, Goel D, Narwaria M, Baijal M, Dukkipati N, Chowbey P, Bhojwani R, Goel R, Aggarwal S, Borude S, Patolia S, Shah S, Dhorepatil S, Patnaik S, Kalhan S, Ugale S, Palanivelu PR. A Delphi consensus on the surgical technique of laparoscopic sleeve gastrectomy: An obesity and metabolic surgery society of India initiative. J Bariatr Surg 2023;2:79-84

How to cite this URL:
Bhasker AG, Tantia O, Khaitan M, Wadhawan R, Kular K S, Baig SJ, Shah S, Bindal V, Vashishtha A, Peters AN, Goel D, Narwaria M, Baijal M, Dukkipati N, Chowbey P, Bhojwani R, Goel R, Aggarwal S, Borude S, Patolia S, Shah S, Dhorepatil S, Patnaik S, Kalhan S, Ugale S, Palanivelu PR. A Delphi consensus on the surgical technique of laparoscopic sleeve gastrectomy: An obesity and metabolic surgery society of India initiative. J Bariatr Surg [serial online] 2023 [cited 2023 Sep 29];2:79-84. Available from: http://www.jbsonline.org/text.asp?2023/2/2/79/382481

Introduction

It has been forecasted that by the year 2040, the prevalence of overweight individuals will double and that of obesity will triple in India.^[1] This rapid increase has led to growing acceptance of bariatric surgery in the population. At present bariatric surgery remains the only effective treatment option for people living with clinically severe obesity. Over the years, there has been an increased interest amongst surgeons to take up bariatric surgery as a subspecialization.

Standardization is the way forward for every maturing specialty and with rising numbers of bariatric procedures; it has become the need of the hour. The WHO has defined standardization as “the process of developing, agreeing on and implementing uniform technical specifications, criteria, methods, processes, designs or practices that can increase compatibility, interoperability, safety, repeatability, and quality.”^[2] Standardization is important to accurately assess future outcomes, facilitate the training of aspiring surgeons and has an impact on future policy decisions.

Laparoscopic sleeve gastrectomy (LSG) is the commonest bariatric operation performed across the world and constitutes 46% of all bariatric procedures.^[3] The perceived simplicity of its surgical technique as compared to other bariatric operations is one of the causes for its popularity amongst surgeons. Despite the global popularity, there is still a lack of absolute clarity regarding the surgical steps of LSG. As LSG is also a part of many other sleeve-plus procedures, it is imperative to have some kind of standardization in place. To this effect, a Delphi consensus was initiated by the Obesity and Metabolic Surgery Society of India (OSSI). The Delphi method is a commonly used method to reach a consensus for key steps of multiple surgical procedures.^[4] This article presents the findings of the Delphi consensus conducted by OSSI.

Methods

OSSI conducted Delphi consensus on the technical aspects of Roux-en y gastric bypass, sleeve gastrectomy, one anastomosis gastric bypass, bariatric nutrition, and perioperative care. This paper presents the findings of the sleeve consensus. This consensus was based on the Delphi method.^[5] OSSI assigned a facilitator to conduct the consensus (AGB). The facilitator prepared the questionnaire, conducted the voting, analyzed the data, and worked on the manuscript. Questions regarding nutrition and peroperative care were not included to avoid repetition as they will be published separately.

Participant selection

Twenty bariatric surgeons were selected as experts based on their years of experience in LSG, overall patient volumes, publications, and the recommendations of the executive committee of OSSI. [Table 1] enlists all the experts included in this study. All identified experts were sent an invitation E-mail regarding the Delphi protocols and to seek their consent for participating in this consensus. Once their consent was obtained, all participants received E-mails with a link to a web-based questionnaire in the form of a Google Survey (https://docs.google.com/forms/d/1933AcZeZ2s5G2Rgq01AJuH35AG1XsFb9nbn5yDYV3Vo/edit). In the first E-mail, participants were asked to choose their response from the multiple choices presented in the survey. Reminders were sent on the 14^th and 21^st day.

Table 1: Experts for the laparoscopic sleeve gastrectomy Delphi consensus

Click here to view

Any statement that achieved 70% agreement between the participants was taken as consensus.

For statements that did not achieve consensus, a round 2 was initiated once again with the help of a Google survey.https://docs.google.com/forms/d/1w0WQaROZjULlXZeemwSvw_w908f7CSwRvBVCKmMTu7E/edit). In this round, results of the first round were shared along with relevant literature and experts were asked if they would like to revise their response in view of the presented evidence. A 3 weeks' response period was allowed once again for Round 2.

Results

A 100% response rate was achieved in both the rounds. Consensus flow is shown in [Figure 1].

Figure 1: Consensus flow in the two Delphi rounds

Click here to view

Consensus was achieved on 22 out of 26 questions. Consensus questions and the responses are listed as under:

Preferred patient position:

Preoperative upper gastrointestinal (UGI) endoscopy must be performed for all patients before LSG (key question):

Recommended method for entering the abdomen (key question):

Preferred surgeon's position: 66.7% of the experts preferred to stand in between the patient's legs and 33.3% preferred to operate standing on the right side of the patient (consensus not achieved)

Liver retraction is necessary while performing sleeve gastrectomy (key question):

Dissection must begin 3–5 cm proximal to the pylorus while performing LSG (key question):

The left crus of diaphragm must be completely dissected while performing LSG (key question):

If a moderate to large hiatus hernia is found during LSG, which procedure must be recommended? (key question):

A gastric calibration tube must be routinely used while performing LSG (key question):

The recommended size of the GCT must be 36–40 Fr. (key question):

GCT must be inserted before the first stapler fire (key question):

From which port should the first stapler be fired? (key question):

First stapler fire must be 3–5 cm proximal to the pylorus (key question):

Care must be taken not to narrow the sleeve at the level of the incisura (key question):

First stapler fire consists of green cartridge (4.1 mm) or a purple tri-stapler (3–4 mm) cartridge (key question):

Second stapler fire consists of blue cartridge (3.5 mm) or a purple tri-stapler (3–4 mm) cartridge (key question):

Third and subsequent stapler fire consists of a blue cartridge 3.5 mm) or a purple tri-stapler (3–4 mm) cartridge (key question):

Last stapler fire must be 0.5–1 cm lateral to the gastro-esophageal junction (key question):

Hemostasis on the staple line can be achieved by-hemostatic clips, cautery, suturing, or hemostatic sealant solutions (key question):

Staple line reinforcement is necessary (key question):

If the answer to the above statement is yes, then please state the preferred method for staple line reinforcement: 77.8% experts recommended oversewing as the method of choice if staple line reinforcement was being done (consensus achieved)

Omentum must be routinely anchored to the staple line (key question):

A leak test must be performed after the completion of LSG (key question):

Intra-abdominal drain must be inserted after LSG (key question):

12 mm trocar sites must be routinely suture closed (key question):

Oral contrast study is advisable on postoperative day 1 (key question):

Discussion

This is an initiative of OSSI and is the first attempt toward a nationwide consensus on the step-by-step surgical technique of performing LSG. The Delphi technique has been recognized as a valid tool to reach a consensus between experts for a particular topic. The present expert group was representative of the LSG performing bariatric surgical community in India and was recommended by the executive committee of OSSI.

Sleeve gastrectomy remains one of the most popular procedures among Indian surgeons.^[6] With a nationwide registry in place and health insurance coming in, it is now imperative to standardize and streamline bariatric operations. Standardization is important to assure safety to protect patients, to promote interoperability and reproducibility, to promote common understanding about the procedure and to enable measurement and evaluation of performance.

In the past, there have been similar attempts to standardize LSG.^{[7],[8],[9],[10],[11]} However, when it comes to universal application, there can be challenges such as geographical heterogeneity, differences between healthcare systems in different countries, and diversity in views and practices of health-care practitioners. Patients in different countries also display biological, cultural, and social diversity.

In this study, out of 26 questions, 23 questions were identified as key questions.

Contrary to earlier studies and surveys, one of the practices that have come to fore in the last few years is regarding the preoperative need for a UGI endoscopy.^[8] With GERD being touted as one of the main complications after LSG and due to the concerns regarding developing Barrett's esophagus in the long term, there has been an increased emphasis on performing presurgery UGI endoscopy in patients planned for LSG.^[12] 75% of experts in our study recommended a preoperative UGI endoscopy for all patients undergoing LSG. A similar consensus was presented by Mahawar et al. in their study published in 2020 where 79.2% of the participants agreed on the need for a presurgery UGI endoscopy.^[11] This also explains the need for dissecting the left crus during LSG. 85.7% of experts in this study agreed that the left crus must be dissected properly during surgery to enable complete resection of the fundus, to identify the angle of His, and to rule out a hiatus hernia. When the group was asked about their choice of procedure in a case of medically refractory GERD with hiatus hernia-an overwhelming 100% response was – Roux en y gastric bypass. None of the experts recommended LSG for such a patient.

Although a consensus could not be reached about the technique of entering the abdomen, most experts (65%) preferred to enter the abdomen using a Veress needle as compared to 30% who used an optical trocar for entry. Ninety-five percent of the experts also agreed on the routine use of a liver retractor while performing LSG.

The use of GCT during LSG has been established before and an overwhelming 95.2% experts in this study recommended using a GCT during LSG. 76.2% experts preferred to insert the GCT before the first stapler fire. Since the inception of LSG, the size of GCT has been a point of discussion. If the size of the bougie used for calibration of the gastric sleeve is too small, it can impact the leak rates. On the other hand, higher diameters of GCT may lead to inadequate weight loss or faster weight regain in future.^[13] While back in 2013 most surgeons were using mixed GCT sizes between 32 and 50 Fr, in the present study, 95.2% of the experts agreed on a GCT size between 36 and 40 Fr. This is in accordance with one of the largest worldwide surveys done on perioperative practices of LSG in 863 surgeons.^[10] Forty percent of the surgeons in this survey reported using a 36 Fr GCT.

Antrum size or the distance of resection from the pylorus has been debated in the past. There have been two schools of thought with some surgeons preferring to resect the antrum and some preferring to preserve it. Antral length reported in the literature varies from 2 cm to 6–7 cm.^[14] It is suggested that antrum-preserving surgeries tend to improve gastric emptying, decrease intra-luminal pressure, prevent distal stenosis, and decrease the chances of proximal leak or reflux. On the other hand, antral resection tends to reduce gastric distensibility leading to early satiety and probably better weight loss. In a randomized study, Francesco Pitta et al. have reported that there is more acid reflux at 6 months in antral resecting sleeves, however, this difference is equalized at the end of 24 months.^[14] In this study, 85.7% of experts agreed that dissection must begin 3–5 cm proximal to the pylorus. This was similar to the perioperative practices survey of 863 surgeons where 72.65% reported antral resection between 3 and 5 cm.^[10]

Ninety-five percent experts in our study agreed that care must be taken not to narrow the sleeve at the level of the incisura. This was similar to the findings in the 2021 sleeve consensus by Mahawar et al.^[11] Narrowing at the incisura is one of the contributing mechanical factors for distal stenosis leading to increased intra-luminal pressure and subsequent proximal staple line leaks.^[15]

Not much evidence is available regarding the choice of linear stapler reloads in different parts of the stomach. Stomach tissue thickness varies from being the maximum in the antrum to being the thinnest in the fundus. Matching closed staple height to tissue thickness has been recommended while selecting the staple reloads. The choice of appropriate stapler can have an impact on leak rates as well as staple line bleeding.^[16],[17] In this study, 73.7% agreed that a green (4.1 mm) or a purple tri-stapler (3–4 mm) cartridge must be used for the first fire in the antrum. While everyone agreed on using the purple tri-stapler for the second fire, the opinions were mixed when it came to choosing between green and blue (3.5 mm) cartridges and no consensus could be reached. For third and subsequent fires, 89.5% agreed that blue or purple cartridges can be used.

All experts agreed that the last stapler fire must be 0.5–1 cm away from the angle of His. This was similar to the 2021 consensus by Mahawar et al. Multiple studies in the past have also emphasized to stay at least 1 cm away from the gastro-esophageal junction to prevent leaks.^[11]

The literature is equivocal and contradictory when it comes to staple line reinforcement. There are studies that do not show any difference in leak rates after reinforcement whereas some show otherwise. However, there is some evidence that reinforcing the staple line leads to a decreased incidence of bleeding.^{[19],[20],[21]} In our study, 71.4% of experts agreed that hemostasis on the staple line can be achieved with hemostatic clips and 71.4% agreed that there is no need for staple line reinforcement. Eighty-one percent experts did not see any merit in routinely anchoring the omentum to the staple line.

71.4% of experts agreed on the routine use of an intra-operative leak test and 76.2% did not recommend the use of intra-abdominal drains.

Strengths and weaknesses

This consensus included 20 Indian bariatric surgeons with many years of experience in the field. Few of these experts have served as presidents of OSSI in the past. One of them has served as the president of the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) as well as IFSO-APC. Many of them are office bearers in OSSI or have held a position in the past. In addition to years of experience, they also have multiple academic publications on the subject and can justifiably be considered experts in this field. This exercise must help to streamline the technique of LSG in India and can be used as a basis for future studies.

The cutoff of 70% for the consensus was arbitrary, however, 70% cut off has been used in multiple consensus studies done in the past. Hence, we decided to follow the same for this study. At the end of the day, consensus statements are considered to be opinions and more robust clinical studies are needed to confirm these findings. We do believe that until then, these can be used to guide practicing Indian surgeons as well as being the basis for future studies.

Conclusion

Bariatric surgery has come a long way in India since its inception in the late 90s and continues to evolve. In any specialty, it is important to introspect at regular intervals to consolidate and standardize existing surgical practices. As a conscientious society, OSSI has initiated multiple efforts toward this goal. This Delphi consensus is also a step towards improving the quality of surgical outcomes of LSG in India. This document has attempted to establish technical specifications of performing LSG which will in turn help to maximize the reliability and safety of the procedure. Until more robust studies come in, this consensus statement will help to provide a reference document which outlines the best way to perform LSG. This is a first step to provide a continually evolving foundation that enables the entire specialty to thrive better.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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