Introduction

It is not easy for surgeons and patients to decide whether to choose sleeve gastrectomy over a gastric bypass or vice versa.

Rates of revision surgery after primary RYGBP have been recorded in the long term, maybe up to 10%

Reasons for revision include:

• Weight regain
• Marginal ulcers and gastro-gastric fistula
  Internal hernia
• Malnutrition and efferent limb syndrome
• Bile reflux has also been reported in 1-5% of patients

Caveats of revision surgery

It may be relatively easy to schedule patients for a gastroscopy and re-look laparoscopy to check for ulcers, adhesions or internal hernia or schedule a laparoscopic cholecystectomy for uncomplicated gallstones and biliary colic

But in general revision surgery after Roux Y gastric bypass is very difficult to do

Also revision surgery for weight regain may have very unsatisfactory results

Some patients after gastric bypass may have chronic abdominal pain with a CT scan, normal gastroscopy and laparoscopy

• Chronic pain may be very difficult to manage and there may be no solutions

Technical aspects of RYGBP The surgery was first described in 1967, the Roux limb length that was performed was 30-35cm   When bariatric surgery became popular in the 1990s, the BP limb was 50-75cm and the Roux limb was 100-150cm   More recently with current bariatric surgery the length of the BP limb may be longer (>100cm) and the Roux limb may be shorter (>50cm)

Longer lengths for the BP limb

There are many variations in performing the RYGBP

There is no standardized limb lengths for the bilio-pancreatic (BP limb), alimentary (Roux limb) or the common channel

These variations may also varies depending on surgeon’s preference and the patient’s characteristics (BMI, medical co-morbidities and other factors)

Recently studies have found that elongation of the alimentary limb have little effect on weight loss

Some prospective studies initially reported that a longer BP limb length have better weight loss but recent randomized control trials showed no short or long term differences in weight loss (up to 2 to 3 years post op)

After 5 years BP limb length of >100cm have better odds to achieve 25% total body weight loss (TWL)

Longer BP limb length (>100cm) may also be more beneficial for patients with T2DM, HPT, dyslipidaemia and OSA

• The exact mechanisms for this is undetermined but for known it is believed to be due to adaptations in gut hormones, rapid transit of undigested food, upregulation of hormones such as GLP-1 and PYY
• There are also changes in bile acid concentration and microbiome

However with a longer BP limb there may be more micronutrient deficiencies

The risk of acid and/or bile reflux may be higher with a shorter alimentary limb

Longer lengths for the alimentary limb

Some patients reported reflux symptoms with a shorter alimentary limb length

Increasing the length of the alimentary limb length to 100cm may or may not help with the acid or bile reflux

A longer BP limb length may also have a higher risk for internal hernia and nutritional deficiencies (shorter total alimentary limb length)

Weight loss outcomes

Although a longer BP length may achieve better weight loss at 5 years but the differences in % total body weight loss may not be significant at all (maybe only a few kgs different)

Hence the trend nowadays is that more surgeons are recommending a longer a BP limb length (>100cm) for better resolution of medical co-morbidities such as HPT, T2DM, etc but the patient should be aware of the slightly higher risk for reflux

Long term results after RYGBP

Several meta-analysis comparing sleeve gastrectomy versus Roux Y gastric bypass showed better weight loss result with the bypass compare to the sleeve after 5 years

However it is important to be aware that even after Roux Y gastric bypass weight regain will occur with time

• >20% TWL after 10 years may be observed with the RYGBP but there will be weight regain after 5 years
• One study reported 31% of patients have recurrent weight gain by over 15%

Other issues after RYGBP may include:

• Gallstones may develop in 28% of patients
• Internal hernia and small bowel obstruction may develop in 9.4% of patients
• Iron and vitamin B12 deficiency in a small number of patients which may occur 2 to 3 years after surgery (which may also be partly due to PPI medication use)
• Gastric ulcers which may occur 3 or 4 years after surgery

Again revision surgery for weight regain after RYGBP is difficult to perform and the weight loss results often may be fairly unsatisfactory

Recently there are also issues raised with hypoglycaemia after gastric bypass especially for patients without T2DM These are serious major concerns which may dampen the enthusiasm for performing gastric bypass surgery over a sleeve gastrectomy