Sleeve Gastrectomy

Currently is the most common type of surgery performed in Australia and is gaining momentum in other countries as well. The surgery was discovered accidentally, as it was the first stage of laparoscopic duodenal switch surgery. Due to technical difficulties in patients with a BMI 60 and over, some cases of surgery were cut short after finishing the first stage, which was to sleeve the stomach. Many patient didn’t go back for the second stage as they lost enough weight and maintained it, and the idea of sleeve gastrectomy (SG) as a stand-alone procedure for weight management developed around year 2000.

Sleeve gained popularity over lap band due to higher success rate and better life style. Medium term complications are much less than lap band, currently significant number of lap band patient experience the treble effect of the band on the esophageus, severe dilatation and reflux, acid and non-acid reflux. Popularity of sleeve gastrectomy has accelerated since 2010, as it can be performed even in patients with previous multiple abdominal surgeries, as compared with gastric bypass or other surgeries which would necessitate conversion to open surgery.

The principle of SG, is to reduce the size of the stomach down to 100 – 150 ml. In practice this size goal serves only as a guideline, and is slightly different between practicing surgeons. Although the principle of the operation is consistent between different surgeons there is variation in the finer points of surgery with a SG such as the amount of stomach removed and the exact shape which will optimise outcomes. My own technique have also undergone some changes throughout my years of practicing.

Sleeve works by altering size / shape of the stomach, decreasing Ghrelin hormone and altering vagal nerve signals to the brain. This is to counteract against the second strongest signal in our brain, the hunger signal which is the main cause of diet failure. This signal together with breathing signal are vital to keep us alive. Food and oxygen are important element in energy production ( calories) which keeps our body alive and kicking. So it is our survival instinct which push us to eat.


Generally 100 – 250 ml is an acceptable size. We are producing one size fits all, and have only a few pre-operative hints with some patient to lean toward smaller size stomach, but otherwise we are trying to produce same size for all comers. Too small a size might produce severe food intolerance and poor life style, although the patient could lose all the excess weight and in short period of time. It is very important to strike the balance right, which is easy to say but hard to achieve sometimes.

The size of stomach which allows you to eat close to entire size and any food you like, I think this is the ideal size. Desperation or the push to lose more weight and gain more patient satisfaction could have led some surgeon to produce excessively small stomach. The smaller the size the higher the leakage rate and other complications.

Stomach will never regrow but could stretch slowly. Nobody knows what is the maximum stretching ability our stomach has, but shouldn’t double in size. Up to 250 ml is acceptable size.


Attention to shape is gaining more interest as it plays very important role in combination with size in the determination of patient progress. The ideal shape is gradually increasing size from the cardia to the antrum. Axial rotation, angulation and narrowing at the mid stomach (the incisura) are important issues that needs special attention by the surgeon.

Leaving or retaining some fundus (the upper thin part of the stomach), could lead to weight regain as this part could stretch and allows the patient to eat more. It also affects the number of remaining Ghrelin producing glands.Leaving too much of the antrum (the lower portion of the stomach), again allows bigger portions of foods and could also stretch needing redo-surgery.

Responsive image

Ghrelin Hormone

Is a hunger producing hormone located in microscopic glands inside the flesh of the stomach and very concentrated at the upper part. Surgery will not remove it all but majority will go with proper sleeving of the stomach.

Responsive image

About 30% of patients have to remind themselves to eat due to complete loss of hunger signals, whilst the other 70% still feel hunger but no where near the intensity prior to surgery. Other non-consistent changes could be encountered, like for example losing interest in your favourite food and being unable to tolerate smoking.

Ghrelin has multiple effects on our body including bone mineralization, muscle growth, and repair of intestinal cells.

Vagus Nerve

This nerve conveys direct information to the brain about status of the esophageus, mainly the speed the food bolus travelling down to the stomach. Usually if the stomach is empty, it will take 4-8 sec for the bolus to reach the stomach once swallowed. With a sleeved stomach, the new tube like stomach is not as welcoming and fills up with a few mouthfuls, leading to significant slow down of the passage of food bolus. Signal through the nerve then will tell the brain that the stomach is full and should urge us to stop eating.

Other possible mechanism, could play part in the weight loss following sleeve gastrectomy, like producing dumping syndrome, which is not as common as in gastric bypass surgery.

The Surgery

The operation performed laparoscopically, (keyhole surgery) almost all the time, with few exceptions like patients with previous multiple complex open surgeries.

Responsive image

Pre-operative preparation

Patient should be assessed for suitability for bariatric surgery and anaesthetic risks:

  • We will need to know every single details of your general health, medications, previous surgeries, allergies — etc.
  • Blood tests, ECG and other investigations as needed
  • Medication review and adjustment might be needed. blood thinning medications should be dealt with properly depending on the individual patient circumstances
  • Diet prior to surgery is important to plan, some patient might not even need any diet while others might not proceed unless planned % of weight loss prior to surgery achieved. All these plans will be decided upon during the consultation. Aim of diet is to make the surgery safer, by softening the liver, improving heart and lung functions — etc.
  • Planning your work, family and social commitments
  • Psychological issues should be discussed, medication management pre and post surgery is important.
  • Setting plans about managing diabetic medication
  • Cardiac and blood pressure medication should be continued, you could even have them at the day of surgery with small sips of water.
  • Cardiac stents, and management of aspirin and plavix should be discussed.
  • Fasting before surgery, for patient on morning list, should fast from midnight the night before surgery. For patient in the afternoon, could have liquid in the morning and water up to 4 hours before surgery, unless issues with lap band and oesophageal dilation is contemplated.
  • Diabetic medication should be omitted on the day of the surgery
  • Brisk walking for few hours every day before surgery will improve recovery post surgery.
  • Smokers should attempt quitting few weeks before surgery, otherwise should expect breathing difficulties and frequent coughing which is quite painful following surgery.
  • Alcohol together with weight put more burden on liver and increases the severity of fatty changes.
  • Should inform us of any significant previous anaesthetic reactions or any significant allergies.

Pre-operative preparation

  • Hospital will contact you about your approximate time of surgery
  • Formal paper works and nursing check
  • In the operating theatre, few formal check ups and anaesthetic review
  • Positioning on operating table, intravenous cannula inserted, O2 by mask, and other preparation
  • Once anaesthetic medication given, it will be a matter of 30 – 40 sec and you will be fully anaesthetised.

The procedure

  • Position on the table and proper strapping ensured
  • Operation site cleaned with antiseptic and proper drapes used
  • The first incision for camera insertion is just under the left rib cage (anterior axillary line)
  • Other working ports inserted under direct vision and the anatomy checked as below
Responsive image
Responsive image
Responsive image

The yellow fatty tissue in the bottom of the picture is the greater omentum (abdominal policeman or lady), will be dissected off the stomach as you could see were the arrows are in the next picture. This will allow the resection of the lateral border of the stomach following the insertion of calibration tube (Bogie)

Next Bogie in black / blue inserted by the anaesthetist

Responsive image

The other important point is the shape of stomach, this area is the current interest as we think it has a lot of influence in weight lost, quality of life and complications.

As you could see above in the dark lined shape, this is the final shape of the remaining stomach. Nice and narrow at the top and slowly curving and increasing in size as we go towards the lower end. I also fold and stitch the lower end using non-absorbable stitches to prevent future stretching / dilatation and possible weight regain.

Responsive image

Resect the eft lateral border

Next step of the surgery is to resect the left lateral border of the stomach using stapler device and trying to leave stomach of 100 – 150 ml size, apart from experience there are no other definitive ways to measure the size at the time of surgery, so surgeon’s experience will play important part in this surgery.

Responsive imageResponsive image

Once the stapling finished, the next step will be the re-enforcement of staple line by bringing back the fat layer, (omentum) and stitching it to the staple line. This process will also stabilize the new stomach prevent twisting and bleeding from the staple line. The last quarter of the staple line will be folded to re-shape the lower part of the stomach were stapling is difficult and could lead to complications.

By finishing this step the operation is almost finished. Final inspection, instillation of local anaesthetic and retrieval of the excised stomach through the largest port site are the remaining steps. Wound cleaning and closure using dissolvable stitches under the skin. Steristrips and water proof dressing are applied.The anaesthetist will slowly reverse the anaesthetic and will remove the breathing tube once the patient is wake enough. You wouldn’t remember or recall any of these events, due to the heavy sedation on board at the time.


Rest of the recovery will be at the recovery unit and once awake enough you will be transferred to surgical word or high dependency depending on individual cases.

On the day of surgery, you will be nil by mouth, feeling some pain and discomfort. The pain response following surgery is different with different patients, and is dependent on a vast range of factors including age, comorbidities, social demographics and also psychological factors. Generally laparoscopic or keyhole surgery is much less painful than traditional surgery. Fluid is introduced through intravenous cannula and oxygen is given through mask or nasal tube.

Day one post surgery, you will be assessed in the morning checking your suitability to start water trial and progression to liquid. Should be able to come off the bed and move around.

Medication will need special attention:

Diabetic medication: during pre-operative diet period, usually you will need half of the dose; you should stop all diabetic medication on the day of the surgery; your blood sugar will be monitored post-surgery and we could give you small frequent doses of rapidly acting insulin for short period of time if needed. Majority of patients will not need medication, as the amount of calories ingested is very small. If you are on long acting insulin, the dose will be slowly decreased aiming at stopping them once suitable. Your individual plans will we discussed with you. If you are on a combination of oral medications and subcutaneous insulin, we will try to get you off insulin first whilst keeping oral medications until ready to stop all medication if suitable.

Blood thinners / anticoagulant: scenarios are different depending on individual patients circumstances and plans will be set before surgery. Almost every patient will have Clexane injection, to prevent clots. Some will need to have it for few weeks if previous history of deep venous thrombosis.

Blood pressure medication: depending the blood pressure, as some will go the other way, low pressure. If needed majority of blood pressure medication could be swallowed.

Responsive image
Responsive image

Antidepressant, and other psychiatric medication: most of these medication could be used on the first day, but if suitable we will try to delay the use for few days, or if liquid alternative present, some could be crushed. All medications are designed to dissolve, so even if the tablet stuck in the middle of new stomach, should eventually dissolve and pass down.

Arthritis medication: it is very important to stop these medication until full diet allowed. Using alternatives and suppositives might be needed

Cholesterol medication: no need to restart these medication , and if needed might be started few weeks later.

Other medication: should be discussed and stopped or restarts as needed.

Herbal medications: should be stopped, as we don’t completely understand their effect if any.