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Why should I consider weight loss surgery?

Surgical treatment is an option for patients who have attempted unsuccessfully to lose weight by non-surgical treatments. Surgical treatment in combination with behavioural modification is a proven method of achieving long-term weight loss for obese people.

Being overweight is closely linked with obesity-associated health conditions, including diabetes (high blood sugar levels) hypertension (high blood pressure), heart disease, hyperlipidaemia (high blood fats), sleep apnoea, infertility, social isolation and depression. Studies have shown certain obesity-associated health conditions have improved or resolved after surgery.

Gastric bypass and Lapband surgery promote weight loss by restricting the amount of food that can be eaten so that fewer calories are absorbed.

What happens before surgery?

  • You will have your first consultation with your surgeon, who will explain all the surgical options which are available to you.
  • You will be referred to the dietician, who will advise you regarding a healthy diet and what you can expect to eat after surgery.
  • You will be referred to a respiratory physician who will assess you for sleeping disorders and especially for obstructive sleep apnoea - which is very common amongst morbidly obese people.
  • You may be referred to a cardiologist who will assess your heart.
  • You may be referred to an endocrinologist who will assess your for diabetes or other endocrine gland disorders.
  • You will be referred to an experienced psychologist.
  • You will be given the contact details of patients who have undergone bariatric surgery already so that you can talk with them.
  • You will be advised to attend the obesity patients' support group which meets at the Bon Secours Hospital every month and is made up of patients who have had surgery and those who are thinking about it.
  • You will be advised to review our obesity surgery website at obesitysurgery.ie
  • You will be admitted at a later date for tests to make sure you are fit for surgery.
  • Your case will be discussed by the Bon Secours Multidisciplinary Team.
  • You will have a second consultation with your surgeon approximately 4-6 weeks after the first consultation. On this occasion, you will decide which procedure you wish to have. If you have had the all clear medically, a date will be set for surgery. Two weeks prior to this date you will commence a special diet. This will allow your liver to shrink and will make the surgery easier and reduce the risk of complications.

How do I prepare for the surgery?

  • You will be admitted to hospital the day before your surgery.
  • You will meet the anaesthetist before going to surgery.
  • Your surgery will be performed under general anaesthesia (you will be put to sleep).
  • The anaesthetist will explain the anaesthetic to you and answer any questions that you may have.
  • When you go for the operation you may be put to sleep in the operating theatre itself.

If you normally take Warfarin or Aspirin or anti-inflammatory drugs for arthritis you will usually be instructed to stop taking these drugs at least a week before your operation because of their effects on blood clotting.

To reduce the risk of blood clots you will be given an injection of anti-coagulant (blood thinner) into your skin. You will be asked to wear elastic stockings and special plastic compression cuffs around your legs.

Postoperative pain management will be discussed with you. It may be suggested that you have a PCA (patient controlled analgesia) after surgery. This is a device, which allows you to give yourself pain-killing drugs, and is connected to a drip in your arm. When you press the handset a small dose of the drug will be delivered directly into your drip in your vein. This is a very safe method of pain relief and you cannot overdose/give yourself too much of the pain killing drug.

Once prepared for surgery you will be taken to theatre by the theatre escort team.

It may be necessary for you to have a urinary catheter inserted into your bladder during your surgery. This allows your urine output to be monitored. The catheter will be removed once you are drinking normally.

What happens after surgery?

After surgery, you will be monitored in the post anaesthetic care room. You will be sat upright and will have oxygen in place to help you with your breathing. You will also have a drip in your arm to provide you with fluids. Pain relief is administered via the PCA when you press your handset. This will have been discussed with you. If you do not have a PCA you will be given painkillers by injection or orally.

Some patients require close monitoring in the early post op stage and are cared for in the high dependency unit. However, most patients go back to the ward, where they receive specialized nursing care.

The day after your surgery you may have a special x-ray test called a 'gastrograffin' swallow or a "CT" scan if you have had a laparoscopic gastric bypass (not after lapband). This is to confirm that there is no leakage from the bowel. If this is OK you will be given sips of fluid to drink, the amount will be gradually increased over the next 24 hours. Once you are tolerating adequate amounts your drip will then be removed.

Very early after surgery you will be encouraged to mobilize. This to prevent post op complications eg. Thrombosis (blood clots) and a chest infection.

The dietician will visit you on the ward and discuss the diet you need to follow now that you have had your surgery.

Approximately 3-5 days following surgery patients are usually ready for discharge home (2 days following gastric band).

You should keep your wounds clean and dry for 5 days - using waterproof dressings if you choose to have a shower. The stitches are usually dissolving and therefore will not need to be removed.

A member of nursing staff will check your wounds before you are discharged and you will be advised when to remove the wound dressings. If your wound site appears red and inflamed or is leaking fluid once you have been discharged you must seek advice from your GP or contact the ward for advice.

Most patients resume working 4-6 weeks after surgery and can begin driving after two weeks. It is however always advisable to check with your own car insurance company first.

Try to incorporate regular exercise in your daily routine. Start with gentle exercise such as swimming or walking.

Sexual activities can be resumed once it is comfortable for you.

Your consultant will see you at regular intervals at your outpatient's appointment.

Surgery can only assist you to lose weight; YOU are the main contributor to you success for weight loss after surgery.

What will prevent me from losing appropriate weight?

  • Eating high calorie foods
  • Drinking high calorie drinks - this includes alcohol
  • Snacking between meals
  • Not exercising regularly or sufficiently.

What can I eat after surgery?

It is initially very difficult to take much food or fluid due to tissue swelling. This improves progressively over the first few weeks and you will be able to eat more solid food. Initially drink plenty of fluid between meals but avoid drinking when you are eating as this will fill up the stomach pouch quickly. Carry a bottle of water with you throughout the day and sip continuously. Our Dieticians will give you good advice regarding this.

It is crucial to avoid eating in between meal times but it is important to sip fluid constantly as you may otherwise become dehydrated. High protein foods such as milk and meat and fish are very important after surgery. Avoid fizzy drinks or let them go flat before drinking them. Otherwise they will fill up the stomach pouch too quickly. Avoid alcohol which is high in calories. Avoid sweets, crisps or sugar. These may cause dumping or diarrhoea.

What medications will I need after surgery?

You will need to take multivitamins, iron and calcium supplements (Calcichew 1000mg od) long term (Not after gastric band). Otherwise you will suffer from deficiencies. You will also require acid-suppressing medication for at least six months. You will also require vitamin B12 injections at 6 and 12 months. Your GP will organize this for you.

What medical conditions are affected by surgery?

Maturity onset diabetes tends to respond rapidly to gastric bypass surgery. You will notice a fairly dramatic reduction in the amount of insulin or tablets that you require and many patients (approx 80%) stop taking all diabetic medication within a few weeks of surgery. High blood pressure also tends to respond to surgery over a period of a few months. If you are taking blood pressure (or water) tablets you should make sure that your doctor checks your blood pressure regularly for the first 3 months. If you do not reduce your medications you may suffer from dizzy spells - particularly on standing.

Many overweight female patients are infertile and once the weight falls, ovulation and periods may start again. If you do not want to become pregnant, it is important to start using some form of contraception if there is a risk. Pregnancy is safe after the surgery but we would advise you to avoid getting pregnant for the first year. If you do become pregnant inform your GP at an early stage.

Most patients report a significant improvement in their sleeping patterns. Most patients with arthritis and back pain notice a marked improvement in their symptoms. However, paradoxically, back and joint pain can get worse initially due to change in posture following marked weight loss. If you suffered from symptoms of heartburn or gastric acid reflux these symptoms are often made better following surgery. Urinary incontinence is also much improved in those patients who have this problem preoperatively. If you suffer from overactive thyroid your medication requirements will reduce. You should ask your GP to check your thyroid level every three months after the surgery.

Do I need to exercise?

After four weeks, it is important to gradually increase your activity levels and to start taking regular exercise. The importance of exercise in helping you to lose weight cannot be over stressed. Exercise also improves muscle and skin tone and the loose skin which may develop when the fat disappears around the waist, underarms and inner thighs. It also has a beneficial effect on the blood pressure and cholesterol levels.

If possible aim to do exercise every day for at least thirty minutes a time. Start gently with activities like swimming, brisk walking or jogging and if you can, join a local gym and get a personal trainer. Those patients who get into the habit of regular exercise do better after weight loss surgery.

How will I manage my diet after gastric bypass surgery?

Disclaimer: Food tolerance may vary from individual to individual


The dietician will give you advice. The following points should be kept in mind:

  1. Foods high in protein such as milk and meat are very important to aid the healing process.
  2. It is essential to take your vitamin and mineral supplements each day. Take these with water as tea or coffee can reduce the absorption of essential nutrients.
  3. All foods should be pureed consistency.
  4. Take fluids in between meals only and sip these slowly.
  5. Try to drink a pint more fluid than you used to each day to make up for the water contained in food.
  6. Eat slowly and stop eating as soon as you feel full; that extra spoonful might be too much.
  7. If you have problems with a particular food stop eating it for a few days and then try it again. Many people find fish and eggs difficult to start with, so don't worry if you cannot get on with these foods initially. You may find that your tastes change after the operation and you no longer enjoy food which you used to like. Experiment with other foods as you may now like them.
  8. Pureed food can be very bland. After the first few weeks use herbs and spices to make it more interesting.
  9. Do not eat sweets, chocolates or high fat snacks such as crisps as these may cause 'dumping' and/or diarrhoea and will slow down the rate of weight loss.

Week 1 and Week 2 after surgery
Sugar-free fluid diet - 4 fluid meals per day
sloppy porridge, milky drink, soup, yoghurt. Remember to drink in-between meals not with meals. Avoid fizzy drinks

Week 3 and Week 4
Soft pureed sugar-free diet for 2 weeks - 3 small pureed meals per day plus 3 glasses of mild in-between meals
Portion size should be that of ½ a yogurt pot or 2 dessert spoonfuls. Remember to drink in-between meals not with meals. Avoid fizzy drinks

From Week 5
Soft sugar-free diet

  • Breakfast: 1x weetabix, milk NO sugar
  • Lunch: Sandwich - 2 small slices of bread with crusts removed. Filling can be salmon, tuna with low calorie mayonnaise. ½ pot of yogurt.
  • Evening Meal: Small portion of mince meat, mashed potatoes & vegetables - carrots, swede. Yoghurt or soft drink

Are there any serious complications?

  • Heart Attack (rare less than 1% or 1/100 patients)
  • Blood Clot (rare less than 1% or 1/100 patients)
  • Chest Infection (up to 10% or 1/10 patients)
  • Leak from/blockage at the joins in the bowel or stomach perforation (up to 5% or 1/20 patients)
  • Haemorrhage/ Excessive bleeding (up to 5% or 1/20 patients)
  • Wound Infection (up to 5% or 1/20 patients)
  • Death - rare (< 0.5%)
  • Conversion to laparotomy - rare (<1%)
  • Vitamin and mineral deficiencies - these are unusual and are prevented by taking supplements
  • Some complication will occur in 10-20% of all people who have this type of surgery.

Disclaimer: Outcomes may vary from individual to individual

What are the common complications?

  • Vomiting- This may be caused by eating too fast, too much, or food that is too solid. Remember to eat small meals at regular intervals.
  • Diarrhoea - Diarrhoea is not uncommon to start with and usually settles as you restart solids. The most common reason is eating foods high in sugar such as sweets, chocolates, sweet drinks or sugar added to food, or high in fat such as crisps, snack foods, chips, fried foods, cheese and fatty meats.
  • Constipation- This is due to drinking insufficient fluid, or drinking too much fluid which contains diuretics such as tea, coffee or alcohol, or both and the solution is to drink more fluids avoiding diuretics rather than taking laxatives.
  • Hair loss- A proportion of patients (about 1 in 5) note some hair loss. This is reversible and usually due to dietary deficiency.
  • "Dumping"- Approximately 1 in 5 patients become dizzy, feel faint and sweaty and get diarrhoea either just after or a couple of hours after eating. To reduce the symptoms of dumping: Avoid sugar and sugar containing foods and drinks.

Disclaimer: Results may vary from individual to individual

Will the weight stay off?

The gastric bypass operation has an excellent long term track record with good follow up data on several thousand patients who have been observed for up to 20 years. Weight loss is shown to be durable but to achieve good results is a two-way thing and following these rules in the long term is important.

Can I become anaemic?

We do suggest that you ask your doctor to check your blood count once a year to make sure that you are not anaemic although this is usually only a problem in women who have very heavy losses with their period. You should also continue to take supplements.

What happens to the excess skin?

In the same way as you let down a balloon which has been blown up for a long time, the skin will have been stretched and has a tendency to sag when you lose weight, particularly when the obesity has been very longstanding. A number of patients do request cosmetic surgery. Generally, this should not be done until at least 18 months after surgery or until the weight has been stable for at least 6 months - if it is done too soon, and the patient loses more weight, the skin will be too loose again.

What happens to the bypassed part of the bowel?

The bowel that has been bypassed does not wither away but stays healthy and continues to produce its digestive juices. There is no evidence of any increase in any form of cancer following the operation, either in the empty bowel or anywhere else, and in fact the incidence of some cancers, such as cancer of the uterus, is reduced by effective and permanent weight loss.

How will the weight loss affect other medical diseases?

One of the main reasons for performing the surgery is for the medical problems which are associated with obesity, the main ones of which are: diabetes (80% cure in maturity onset diabetes), high blood pressure (50% cure), arthritis (70% noted improvement) (particularly in the knees, hips and back), depression (majority of patients improved), breathing difficulties (majority of patients much improved), infertility, heavy painful periods and urinary incontinence. The majority of patients with gastro oesophageal reflux (heartburn) are cured by a gastric bypass.

Disclaimer : Results may vary from individual to individual

The operation has an excellent and well proven track record for improving or curing these diseases. Other diseases such as irritable bowel syndrome will not be affected one way or the other.

Bon Secours Hospital CUH Trinity College Dublin Royal Adelaide Hospital