The Birmingham experience of high-pressure methylene blue dye test during primary and revisional bariatric surgery: A retrospective cohort study

Abstract

IntroductionLeak following bariatric surgery continues to be associated with morbidity and rarely mortality. With improvement in surgical techniques and stapler design, leak rates have reduced drastically. Intra-operative high pressure Methylene blue leak test (HPMB) is one of the techniques employed to confirm integrity of anastomoses and staple lines. Despite this, evidence for its use remains limited. We evaluated the role of HPMB in detecting and preventing leaks.MethodsA retrospective cohort of consecutive patients who underwent primary or revisional Laparoscopic Sleeve Gastrectomy (SG) or Laparoscopic Roux-en-Y Gastric bypass (RYGB) under the care of five surgeons in three centres across Birmingham, UK, between 2012 and 2016 were assessed. All patients had routine HPMB at the end of the procedure. Demographics, HPMB positivity, and post operative leaks were recorded.Results924 patients underwent bariatric surgery: 696(75.3%) RYGB, and 225(24.3%) SG. 85(9.2%) were revisional procedures.Two HPMB were positive, which necessitated staple or suture line reinforcement with sutures intra-operatively. The patients had an uneventful recovery. 5 patients had postoperative leaks, all of whom had negative intraoperative HPMB: 3 SG patients; and 2 RYGB patients (gastro-jejunostomy anastomotic leaks). There was no statistically significant relationship between positive HPMB and anastomotic leak (Fishers exact test; p = 1).ConclusionDespite routine use of methylene blue dye test in 924 patients, there were only two positive tests. Whilst HPMB may demonstrate technical failure, this study suggests that there is no role for its routine use in primary bariatric surgery. Discontinuation of this practice would reduce risk of anaphylaxis to the dye, cost, and intra-operative time.

The Routine Use of the Methylene Blue Test in Sleeve Gastrectomy: Why Not?

“…Other studies have claimed that there is no advantage in performing the MBT during SG. Kirby et al 18 failed in trying to establish a clinical value for the MBT in bariatric procedures. With a sample of 225 patients who underwent SG, they found three cases of postoperative leaks, all of which had negative MBT.…”

“…Furthermore, authors have also claimed that another reason not to perform the MBT is the risk of anaphylaxis 18 . Although a few cases of allergic reactions have been reported with the use of the methylene blue, there is no report of anaphylactic shock following the use of this dye 2,10 .…”

“…Gastric leaks of early onset usually occur due to stapler misfiring, direct tissue injury (secondary to surgeons' lack of expertise and learning curves) and/or patients' risk factors (including diabetes, smoking and vasculopathies), and, occasionally, these leaks can be caught intraoperatively and promptly closed 1,6 . In order to assess the staple line integrity during the procedure, several tests, such as the methylene blue test (MBT), have been used; however, showing conflicting results 1,13,18 . Although widely used, the evidence supporting the routine use of this test is scarce, and no study have yet confirmed its value in preventing post-SG leaks 18 .…”

“…In order to assess the staple line integrity during the procedure, several tests, such as the methylene blue test (MBT), have been used; however, showing conflicting results 1,13,18 . Although widely used, the evidence supporting the routine use of this test is scarce, and no study have yet confirmed its value in preventing post-SG leaks 18 .…”

Comparative Study Between Laparoscopic Sleeve Gastrectomy and Laparoscopic Mini Gastric Bypass for Treatment of Morbid Obesity.

“…(23) We don't routinely perform intra-operative leak tests (IOLT) in LSG, as they are unreliable and may be more harmful than benificial. (37)(38)(39)(40) Bingham et al (38) performed a retrospective multicenter study to assess the benefits and efficacy of routine IOLT in LSG, the reported that IOLT had -very poor sensitivity‖, as 91% of patients with post-LSG leaks had negative IOLT, and that routine IOLT did not decrease theincidence of post-LSG leaks. Bingham et al (40) in another retrospective study, found that all patients with post-LSG leaks had negative IOLT.…”