Weight loss surgery

The Pre-operative Screening Process

The first stage towards weight loss surgery is embarking on the pre-operative screening process. This process is designed to assess your suitability for weight-loss surgery and to prepare you for the many changes that will occur following your operation. Any issues that could jeopardise the success of surgery are identified at this stage. Please note that surgery cannot be confirmed until the pre-operative screening process has been completed, and it is the duty of the surgeon to refuse surgery if they deem it unsafe.

Surgeon consult

First you will meet Dr Flint to discuss weight loss surgery. A medical history and examination will be performed, and any medical issues will be assessed. If any pre-operative tests are required, these will be organised at this visit.

Dietitian consult

Your dietitian will ask you about your eating habits, review your food records and discuss your individual eating plan. You will be asked to keep records of food consumption prior to surgery and as needed. A detailed guideline will be provided to assist you in managing your meal patterns before and after surgery. Review this plan carefully. It is essential that you adhere to the pre-operative diet BEFORE surgery to aid the success of the operation.

Psychologist consult

Occasionally a psychologist will be asked to review your suitability for this surgery. The visit will include a review of your present lifestyle, your existing support networks, any depression or anxiety issues you may be dealing with, stresses you may face after the surgery, and if you are in therapy, permission will be sought to speak with your therapist.

Days before surgery

Pre-operative Diet

Follow the prescribed pre-operative diet: Usually starts 3 weeks before surgery and is designed to maintain a daily calorie count of no more than 1000 kcal per day.

Medication and Supplements

• Some medication will need to be withheld before surgery.

• Bring your regular medications in their original packaging to the hospital, and follow instructions on which ones to take on the day of surgery.

Special Considerations

• Notify us if you develop a cough, infection, or any change in health in the week before surgery.

• Arrange help at home for the first two weeks after surgery, especially for transportation, meals, and household tasks.

• Plan not to drive for a week after surgery, so arrange for transport and assistance as needed.

• It is normal to feel anxious. Bring something to help you relax, such as headphones, music, or a book.

The day of surgery

• Remove all jewellery, piercings, make-up, and nail polish before coming to the hospital.

• Wear comfortable clothing and bring any hearing aids or glasses you may need.

• Bring your CPAP machine with you if you use one regularly.

• You may wish to bring a friend or family member to accompany you, and drive you home.

• Arrive at the hospital at the specified time and bring all necessary paperwork and identification.

Where will my surgery be performed?

Dr Flint performs his surgery at St Georges Hospital. Please note that the hospital will require payment BEFORE the day of operation.

When do I arrive?

You will be required to arrive at the hospital a few hours before surgery so that the hospital staff can be prepared for the operation.

• If you have a morning operation, arrive at the hospital at 7am. Do not have any food or drink after midnight prior (do not have breakfast).

• If you have an afternoon operation, arrive at the hospital at 11am. Have your last Optifast no later than 8am and drink only water until 10am. Do not have anything after 10am. It is important that your stomach is empty at the time of surgery.

You can expect to stay in hospital for up to two nights.

What happens when I arrive at the hospital?

At the hospital you will be met by a nurse who will take you to your room. They will review your medical history and laboratory tests and may perform an ECG. All documentation will be checked and confirmed.

Prior to surgery you will meet your anaesthetist, who will review your medical history, perform an examination and review any investigations you have had. They will discuss your anaesthesia and post-operative pain control. This is often the first time you will have met your anaesthetist, so it is important you are prepared to ask any questions you may have.

You will also have an opportunity to speak with Dr Flint again prior to surgery.

What happens when I go to the operating theatre?

You will be given a theatre gown to wear that opens at the back. You will also be given leg compression stockings to wear, which are below the knee in length. If they feel too tight, it is important that you tell your nurse. All jewellery, make up and nail varnish must be removed prior to going down to the operating theatre; however, wedding bands may be left on and taped.

There will be a number of people, all doing different things to get you ready for surgery. At times this may feel overwhelming and may be confusing. However, this is entirely normal, as it takes a variety of skilled staff to ensure your surgery is performed safely.

Once in the pre-op suite, an intravenous drip will be inserted into your arm or the back of your hand. Other items will be attached to monitor you during surgery. These include a peg on your finger monitoring your oxygen saturation level, a blood pressure cuff and three stickers on your chest to monitor your heart. This is standard for any type of surgery.

When everything is ready, an oxygen mask will be placed on your face, and you will be asked to breathe in deeply. While you may notice a strange smell, this is oxygen only. You will slowly fall asleep as the anaesthetist inserts medications into your intravenous drip.

What will happen immediately after the operation?

You will wake up either in the theatre or the recovery room. Once awake, you will notice that you are still connected to a number of things, including a drip, oxygen mask and blood pressure cuff. This is entirely normal, and for the first few hours after your surgery you will be closely monitored, and your blood pressure and pulse will be checked frequently. You may also notice that you are wearing foot pumps that might feel like they are pulsating. These are used to help reduce the risks of blood clots.

You may also have a PCA (Patient Controlled Analgesia) which you are able to press if you need pain relief. It is preset, so there is no danger of overdose. It's important to tell your nurse if you feel nauseated or have pain, as you may require additional medication. Being comfortable means you will breathe, move and drink more easily – all things that will ensure you have a positive and rapid recovery.

Once you are awake, your nurse will encourage you to stand up, move around and walk to the toilet as soon as you are able. This early movement is very important and plays a large role in the prevention of complications such as blood clots and chest infections. The use of blood-thinning drugs and leg compression stockings further help reduce the risk of blood clots. You will also be encouraged to take deep breaths, cough and do breathing exercises, all things that will help with your recovery. Movement is the key to reducing the risk of post-operative complications. The more you can sit out in a chair and walk around the ward, the better it is for you. You might find it more comfortable to sit up than to lie down, and you may even prefer to sleep sitting in your chair.

Your drip and the cannula are usually taken down the following day.

Wound care

• Your wounds will usually have dissolving stitches and will be covered in a waterproof dressing. Keep your wound dry for the first 24–48 hours. After this period, you may shower, but avoid submerging the incision in water (baths, swimming) for two weeks.

• After showering pat incisions dry. Inspect the dressing after showering. The waterproof dressing may become wet or loose. If so you may remove it, but try not to disturb the sticky plaster dressing underneath that is adhered to the wound. This plaster normally falls off at two weeks.

• Avoid direct sunlight on your incisions.

• Do not scratch your incisions (it is normal for your incisions to feel itchy).

• Do not apply ointments, antiseptics, or powders to the incision. Simply keep it clean and dry.

• Check your incisions for abnormalities such as unusual drainage, redness, or tenderness.

Diet

• Follow the diet instructions outlined in the post-op diet packet provided by your dietitian.

• Sip fluids regularly during the day to prevent dehydration. A common trick is to have a timer set at 20 minutes to remind yourself to sip regularly. If you feel uncomfortable, withhold drinking on that beep and wait for the next one. As long as you are passing urine 2-3 times a day, you are drinking enough.

Activity

• You can expect to be very tired for 1-2 weeks after your surgery.

• Gradually increase your activity. Start with short walks several times each day. You should be walking around your home frequently during the day.

• Avoid sudden changes in position. Move slowly from lying to standing and from sitting to standing.

• Avoid lifting more than 5 kg for 2 weeks.

• No abdominal exercises for 6 weeks.

• Consult your doctor to find out when you can resume more strenuous activity.

Bowel and bladder

• Monitor your urine output. You should be passing urine 2-3 times a day. It should be clear and without odour.

• Do not strain to have a bowel movement. A stool softener is recommended.

• Contact your doctor if you have black or bloody stool.

Medications

Take your medications exactly as prescribed on your medication discharge instruction sheet. Unless otherwise directed by your doctor, all of your medications and vitamins can be swallowed as they are given. Alternatively, you may crush tablets or use chewable or liquid forms. If you are uncertain how large a pill you can swallow, then it is useful to use the rule that you swallow no pill larger than the top of a thumbtack.

For more information about medications, get in touch or download the weight loss surgery guide below.

Contact Dr Flint at the rooms or your GP if you experience:

• A temperature higher than 38°C

• Your incision(s) opens up or become red, swollen, tender, or have new drainage

• Abdominal pain that is not relieved by your pain medication

• Persistent nausea or vomiting

• Shortness of breath

• Any pain or swelling in your legs

• One leg appears noticeably larger than the other

• Painful, frequent urination or inability to urinate

• Black or bloody stool

• Vomiting blood

P. 03 375 4480

For more information, download the weight loss surgery guide below.

The laparoscopic sleeve gastrectomy, often called the “sleeve”, has a history that stretches back several decades. It did not begin as a stand-alone operation but as part of a much more complex procedure known as the biliopancreatic diversion with duodenal switch (BPD-DS).

In the late 1980s and early 1990s, Dr. Douglas Hess, in the United States, pioneered this approach. He reshaped the stomach into a narrow tube, or “sleeve”, as the first stage of the operation, before carrying out an intestinal bypass.

In the late 1990s, another key figure, Dr. Michel Gagner, working in Canada and later the United States, performed the first sleeve gastrectomy using a laparoscopic or “keyhole” approach. This was a major step forward. Laparoscopic surgery meant smaller incisions, quicker recovery, and less postoperative pain. It made the idea of performing the sleeve more widely attractive.

Around the same time, surgeons such as Dr. Alan Wittgrove were also advancing laparoscopic bariatric techniques, helping to establish minimally invasive surgery as the new standard.

Although originally designed as the first part of a two-stage operation, many surgeons noticed that patients lost significant amounts of weight after just the sleeve, often so much that the second stage of the duodenal switch was not required.

In the early 2000s, surgeons including Dr. Baltasar in Spain, Dr. Regan in the United States, and Dr. Deitel in Canada began publishing their experiences with the sleeve as a stand-alone procedure. Their reports showed excellent weight loss, major improvements in diabetes, blood pressure, and sleep apnoea, and acceptable complication rates.

As evidence accumulated, more centres adopted the sleeve gastrectomy on its own.

By the 2010s, long-term studies confirmed that the operation was not only effective but also safe and durable. From these pioneering efforts, the sleeve has grown into the most widely performed bariatric procedure in the world, recognised by international surgical societies and offered to patients everywhere as a reliable treatment for severe obesity.

The One Anastomosis Gastric Bypass (OAGB) has an interesting journey. The operation was first described in 1997 by Dr. Robert Rutledge, an American surgeon, who called it the Mini Gastric Bypass. His idea was to create a simpler version of the traditional Roux-en-Y bypass by using just one connection between the stomach and the small intestine instead of two.

Early reports showed that patients lost a lot of weight, and the surgery was quicker to perform.

At first, not all surgeons were convinced. Some were concerned about the possibility of bile reflux, and the operation was not widely adopted. However, interest continued to grow.

In the mid-2000s, Spanish surgeons, led by Dr. Miguel Carbajo, refined the technique further. They standardised the way the stomach pouch was made and how much intestine was bypassed. They also gave the procedure a new name: the One Anastomosis Gastric Bypass (OAGB). This helped distinguish it as a recognised surgical option, not just a “mini” version of another operation.

By the 2010s, research and long-term results began to show that OAGB was not only safe but also highly effective for weight loss and improving obesity-related health conditions such as type 2 diabetes, high blood pressure, and sleep apnoea.

Today, more than 25 years after its introduction, the operation is performed worldwide and is included in international bariatric surgery guidelines.

The Roux-en-Y Gastric Bypass, often simply called the “gastric bypass”, is one of the best-known operations for the treatment of severe obesity. Its story stretches back more than half a century and involves several pioneering surgeons whose contributions helped shape modern bariatric surgery.

The roots of the operation go back to the 1950s and 1960s, when surgeons first experimented with different forms of intestinal bypass to achieve weight loss. While these early procedures did lead to weight reduction, they often caused severe nutritional complications. Surgeons began looking for safer ways to combine restriction of food intake with some degree of malabsorption.

In the late 1960s, Dr. Edward Mason at the University of Iowa performed the first gastric bypass operations. He is widely regarded as the “father of obesity surgery”. Dr. Mason initially worked on gastric partitioning procedures and then described the original gastric bypass, which restricted stomach size and rerouted food into the small intestine. His work laid the foundation for what would become the Roux-en-Y technique.

The operation was further refined through the work of Dr. Richard Varco, another American surgeon who contributed to early concepts of intestinal bypass, and later by Dr. Edward E. Mason together with colleagues who promoted gastric bypass as a safer and more effective alternative to pure intestinal bypass.

By the 1970s and 1980s, surgeons adopted the Roux-en-Y reconstruction (named after the Swiss surgeon César Roux, who had described the “Roux-en-Y” method of joining bowel segments in the late 19th century). This reconstruction provided a reliable way to reroute food from a small gastric pouch into the small intestine, reducing complications such as bile reflux and improving patient tolerance.

The next leap came in the 1990s, when advances in minimally invasive surgery allowed the procedure to be performed laparoscopically. Surgeons such as Dr. Alan Wittgrove in the United States performed some of the first laparoscopic Roux-en-Y gastric bypass operations. This reduced recovery time and made the procedure more accessible and popular.

Over time, the Roux-en-Y Gastric Bypass (RYGB) became one of the most studied and widely performed bariatric procedures in the world. Decades of research have confirmed its effectiveness for long-term weight loss and for improving obesity-related conditions such as type 2 diabetes, high blood pressure, and sleep apnoea.

Today, the Roux-en-Y Gastric Bypass remains a cornerstone of bariatric surgery.

The costs differ for each surgery. Here is a list of indicative costs for each of the weight loss surgeries I perform:

• Lap sleeve gastrectomy $21,500

• Lap one anastomosis gastric bypass $24,500

• Lap Roux-en-Y gastric bypass $27,500

• Revision sleeve to bypass $33,800

• Revision band or fundoplication to bypass $38,200

• HDU stay for at-risk patients additional $3,000

Anyone with a BMI above 30 or weight-related comorbidities. We'll also need to conduct tests to determine whether your condition permits successful weight loss surgery.

I am an independent surgeon, but I operate out of St George’s Hospital, one of Christchurch’s leading healthcare facilities. Enjoy comfortable surroundings and the support of dedicated nursing staff delivering quality care throughout your stay.

Weight loss surgery typically requires a 2-night stay.

It depends on the type of medication. Here is a pre-op guide to find out more. If you have any doubt or further questions, don't hesitate to reach out to me or your GP.

Visit the FAQs if you have more questions, or get in touch with me for any other concerns.