Roux-en-Y Gastric Bypass Surgery
Roux en-Y gastric bypass (RNYGB) is the gold standard operation against which all other obesity operations are judged. First performed in the USA in 1967 by Mason & Ito, it has stood the test of time providing reliable, long-term weight loss with little long-term risk of malnutrition or complications. Globally it is the most common procedure with 200,000 gastric bypasses performed in the US alone in 2008. First performed as an open operation it is now mainly performed laparoscopically, reducing hospital stay to two or three days with a shorter time to return to normal activities. It is a more invasive operation, with greater risk of complications than laparoscopic adjustable gastric banding and is not easily reversed.
How Does Roux En-Y Gastric Bypass Work
RNYGB has a physical and hormonal effect. Physically it restricts food intake, portions sizes after the RNYGB are much reduced with an early feeling of fullness. Over-eating causes abdominal discomfort and vomiting. While the majority of the reduction in a patient’s calorie intake is attributable to the restriction, initially there is also an element of malabsorption of fat similar to the duodenal switch. Long-term malabsorption is probably not important as the patient’s body adapts to the bypass. Nevertheless patients do need regular dietetic review and should be tested for anaemia annually after surgery.
RNYGB also reduces a patient’s appetite. The mechanism by which this occurs is not fully understood, but is related to a change in the normal gut hormonal patterns. Bypassing the first part of a patient’s small intestine affects the production of hormones which control appetite. After RNYGB most patients feel far less hungry, often forgetting to eat. Bypass surgery also affects the hormones that control blood sugar and consequently many diabetic patients become non-diabetic immediately after surgery.
The Surgery
While the majority of patients will be suitable for laparoscopic (keyhole) surgery, for some patients open surgery may be a safer option.Irrespective of the approach used, internally the bypass is performed in the same way. Your surgeon will advise you on the best option for you.
The patient is admitted to hospital on the day of surgery. A general anaesthetic is needed for the surgery, it cannot be performed under local or spinal anaesthesia. Laparoscopic surgery uses six small cuts on the upper abdomen, three are about 1.5 cm long and three are about 0.5 cm long. Using a digital telescope and long operating instruments the surgeon performs the procedure in a standardised way. For open surgery, Streamline surgeons use an 8 to 10 cm long midline incision in the upper abdomen that. Most other centres performing open RNYGB will use a much longer incision.
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After Surgery |
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The first step of the operation is to make the Roux en-Y bypass from the small intestine. The small intestine is divided using a surgical stapler 0.75m to 1.25m from it’s origin, approximately 0.75 to 1.5 m from the place of division it is re-joined to the small intestine. This join is made using a combination of a surgical stapler and suturing. The next step is to make a small gastric pouch from the patient’s stomach. Surgical staplers are used to form a vertical pouch of approximately 20 ml in volume. The bypass is then joined to the pouch using a 1 cm diameter join called an anastomosis.
The skin incisions, laparoscopic or open are closed with soluble stitches and local anaesthetic is injected into the skin around the incisions to reduce post-operative pain. A surgical drain, which is a long plastic tube, may be placed close to the gastric join passing through the patient’s abdominal wall to drain into a bag. It will normally be removed after 48 to 72 hours. Similarly, it is sometimes necessary to keep the gastric pouch empty with a fine plastic tube passed through the patients nose into the pouch. This tube is also normally removed after 24 to 48 hours.
After Surgery
After surgery, the patient spends an hour or two in the recovery area of theatre, being closely observed before returning to the ward. The patient has an intravenous drip in their arm for fluid, oxygen through a face mask, heart monitoring via leads on their chest, and blood pressure monitoring with a special cannula placed in an artery in the wrist. The patient will also have pneumatic compression stockings around the calf, which improve blood circulation, through the leg veins during surgery helping to prevent thromboses.
After surgery the patient is usually kept nil by mouth overnight before being allowed to drink small amounts the following morning, building to normal drinking through the first day after surgery. On the second day, soft diet is started ready for discharge the next day. The pain after laparoscopic surgery isn’t usually too bad, it is a bit worse after open surgery but can usually be controlled without too much difficulty. Morphine may be needed in the first 24 hours after laparoscopic surgery and for 48 hours after open surgery. The rate at which morphine is injected is controlled by the patient using a computer controlled syringe, when a button is pressed the syringe injects a small dose of morphine into a vein. Software prevents the patient from over-dosing themselves. After a day or two pain should easily be controlled with paracetamol and ibuprofen. Patients having laparoscopic RNYGB are usually discharged from hospital on the third day after surgery, but may sometimes be fit for discharge the evening before. After open RNYGB patients are discharged on the third or fourth day after surgery.
After discharge, it is important to rest and eat carefully. Most people need two to three weeks off normal activities before returning to work. The pain shouldn’t be too severe and should be controlled with paracetamol and an anti-inflammatory pain killler such as ibuprofen. Patients shouldn’t drive for ten days to a fortnight and should notify their insurer before driving. After RNYGB patients need to stick to the diet recommended by our dieticians, slowly building up too bigger portions and less easily digested foods such as meat and fish. Most medication can be taken as normal although it is sometimes necessary to break tablets or capsules.
Follow Up After Surgery
Good follow up is essential after RNYGB surgery to get the best weight loss and ensure patients don’t develop protein malnutrition or vitamin deficiency. The best follow up advice is given by specialist bariatric dieticians trained to advise patients on diet and vitamin supplementation after bypass surgery. Research has shown that the patients who achieve the best weight loss have worked well with their dietician’s sticking to the prescribed diet. Patients should take a multi-vitamin daily and be checked for anaemia annually by their general practitioner.
Expected Weight Loss & Health Benefits Of Rnygb
Research including many thousands of patients has shown that on average patients having RNYGB lose 66% of their excess weight. Putting this weight loss into context, an average patient with a Body Mass Index of 45 kg/m2, who is 5’6” tall and weighs 19.5 stone is 8.5 stone over their ideal weight. On average with a RNYGB this patient will lose nearly six stone and have a long-term weight of 13.5 stone. The same research compared RNYGB with other surgical procedures, LAGB has an average weight loss of 49% and duodenal switch 70%.
In practice weight loss after RNYGB is affected by many patient factors including age, activity level and basal metabolic rate. Many of Streamline’s RNYGB patient’s have much better than average weight loss.
Health Benefits Of Rnygb
In addition to the weight loss there is a dramatic improvement in the medical conditions commonly associated with obesity.
Raised blood cholesterol is corrected in over 70% of patients.
High blood pressure is cured in over 70% of patients, and medication requirements are usually reduced in the remainder.
Obstructive sleep apnoea is resolved in 86% of patients, snoring improves for most patients
Diabetes Mellitus is cured in up to 90% of patients, often within days of the surgery.
Reflux of acid is usually cured by the surgery.
Low back pain and musculo-skeletal pain is usually relieved or improved.
Risks Of Roux En-Y Gastric Bypass Surgery
DEATH
Roux en-Y gastric bypass is usually safe, research has shown that the risk of death, measured across many obesity centres, after RNYGB is 0.5% or 1 in 200. Streamline’s mortality rates are much better than average, in over 1000 RNYGBs there has been one in-hospital death, a mortality rate below 0.1% or 1 in a thousand. There have been no deaths in private patients or after laparoscopic RNYGB. There has been a few late, post discharge deaths. All the patients who have died have been high risk, usually older, super-obese men with underlying heart and lung disease.
INTRA-ABDOMINAL INJURY & CONVERSION TO AN OPEN OPERATION
The risk of internal injury with laparoscopic surgery is low. It is possible to injure the stomach, spleen or liver. If this were to happen it may be necessary to convert from keyhole surgery to an open operation through an incision from the bottom of the breast bone to the umbilicus (tummy button). This would mean a longer hospital stay and a slower recovery. Similarly with open surgery it is possible to injure the spleen and occasionally it is necessary to remove a patient’s spleen. This should not cause long-term harm but will mean being vaccinated against specific bacteria and needing to take a low dose of antibiotic once a day for life. The risk of internal injury can be reduced by shrinking the liver with the pre-operative milk diet.
BLEEDING
Bleeding after RNYGB occurs in about 1 in 50 to 1 in 100 cases. The bleeding can occur in two ways. In an intra-abdominal bleed blood is lost into the patient’s abdominal cavity, there are usually no external signs of bleeding, but the patient will have a fast heart rate and sometimes a low blood pressure. In an anastomotic bleed, the patient bleeds from one of the joins in their bowel, patients normally pass dark red-black stools and have an increased heart rate. Most bleeding stops with no specific treatment, sometimes a blood transfusion is necessary if the blood loss is significant and occasionally it is necessary to re-operate or look into the patient’s gastric pouch with an endoscope.
ANASTOMOTIC LEAK
Although an anastomotic leak is uncommon it is the surgeon’s most feared complication, other than death, after RNYGB. In this complication one of the joins leaks and intestinal juice seeps into the abdominal cavity. Un-recognised an anastomotic leak can progress to generalised peritonitis which can be fatal. A leak will usually occur in the first two or three days after surgery. Patients complain of severe abdominal pain and have signs of generalised infection including a temperature, high heart rate and low blood pressure. It can sometimes be managed by making the patient nil by mouth and using intravenous antibiotics to treat the infection. If more severe a further operation may be necessary.
WOUND INFECTION
Wound infections are uncommon after laparoscopic surgery, but occur in about 1 in 20 patients after open surgery. They are usually managed with oral antibiotics and should cause no long-term harm.
HERNIAS AND ADHESIONS
After laparoscopic surgery patients can develop internal hernias, where a loop of bowel becomes stuck through a potential area of weakness created by the surgery. With open surgery, a hernia may develop through the midline incision. Either type of hernia can cause bowel obstruction which may need an operation to relieve it and repair the hernia. Adhesions are more common after open than laparoscopic surgery. Adhesions are “scar tissue” that sticks and tethers loops of small bowel; adhesions can trap the bowel causing abdominal pain and sometimes bowel obstruction. It is sometimes necessary to operate for adhesions, dividing them to un-trap the bowel.
RE-OPERATION
Overall about 1 in 50 patients need further surgery after RNYGB to manage complications including bowel obstruction, anastomotic leak, bleeding or hernias.
ANAESTHETIC COMPLICATIONS
Chest infections and heart attacks can occur after Roux en-Y gastric bypass but are not common. Occasionally patients will develop a deep vein thrombosis (DVT), a clot in the deep veins of the leg. Left untreated these can move to the lung, a pulmonary embolism, causing serious breathing difficulties. These are best avoided. Lots of steps are taken in theatre and after surgery to minimise the risk. Patients can help to decrease their risk by giving up smoking before surgery, maintaining a good fluid intake after surgery and walking after surgery.
MALNUTRITION AND VITAMIN DEFICIENCY
Malnutrition and vitamin deficiency are uncommon after Roux-en Y gastric bypass and are best avoided. After surgery it is important to avoid protein malnutrition, this is not always easy as some of the best sources of protein including meat and fish are not easily digested in the first few months after surgery. Following a prescribed high protein diet with regular dietetic review is the best way to avoid malnutrition. Patients can develop vitamin deficiency after surgery, so we recommend patients take a daily multi-vitamin and are checked for anaemia annually. Hair loss after RNYGB is normal and is the body’s response to it’s perceived state of starvation. It always grows back strongly.
Very occasionally, especially in patients who vomit a lot after surgery, rare vitamin deficiencies (thiamine, B6, B12) associated with muscular and neurological impairment (Guillam Barre syndrome) can occur.
Information For Women Of Child Bearing Age
FERTILITY AND CONTRACEPTION
Obesity can cause infertility. Many overweight women find they are infertile, don’t have periods and don’t use contraception. With weight loss many patients start to ovulate again, have periods and with this increased fertility, unplanned pregnancies can occur. It is important to use contraception after obesity surgery. Barrier methods, coils and hormone injections are the most reliable methods. Absorption of some drugs is reduced by RNYGB and after surgery the oral contraceptive pill may not be effective.
PREGNANCY AFTER ROUX EN-Y GASTRIC BYPASS
Pregnancy within the first year after RNYGB is not recommended. But after a year it is safe to become pregnant. Many healthy babies have been born to Mothers who have had RNYGB surgery with us. It is important to inform your obstetrician about your surgery.
Recommended Diet After Roux En-Y Gastric Bypass
Streamline’s dietician will see you before surgery to advise you on the appropriate diet. A low fat healthy diet is recommended although there may be some foods that can’t be tolerated after surgery. Particularly red meat and bread can be difficult to eat after RNYGB as they can stick in the gastric pouch.
Sugar is best avoided after RNYGB as it can cause dumping syndrome. In this condition after eating sugars patients feel nauseous, may have abdominal discomfort, their heart races and patients suffer overwhelming anxiety. Once experienced most patients won’t chance eating sugar again.
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