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Advice for overweight patients having surgery

Find out more about the risks of being obese, and what you can do to minimise them before your surgery.

What is obesity?

The standard way is to refer to body mass index (BMI).

Ideal BMI is 20 to 25 kg/m2. Obesity is 25 to 30kg/m2.

Your shape

If your waist measurement is more than half your height, you have central obesity or you’re ‘apple shaped’. This is due to fat around your internal organs. We associate central fat with diabetes, high cholesterol and high blood pressure.

Am I at increased risk because of my weight?

Although many overweight people are fit and healthy, there are increased risks associated with being obese. It’s more likely if you have central obesity and are apple shaped.

You have an increased risk of suffering a serious complication during or after your operation if you have:

  • high blood pressure
  • diabetes
  • obstructive sleep apnoea
  • history of thrombosis
  • angina.

After an operation obese patients may be more likely to have:

  • chest infections
  • difficulty breathing
  • wound infections
  • poor wound healing.

What can you do to reduce your risk

There’s a few things you can do.

Stop smoking

This improves your fitness and helps you to cope with the stress of an operation. If you’re having orthopaedic surgery, building up strength will help your recovery.

Lose weight

Just a few kilograms of weight loss can make the surgery easier for the surgeon, especially if you’re having laparoscopic (keyhole) surgery.

Control your blood sugar

If you are diabetic, maintaining good control of your blood sugar is will ensure healing and minimise infection.

Use a CPAP machine for sleep apnoea

If you have a continuous positive airway pressure (CPAP) machine for sleep apnoea you should use it every time you sleep, and make sure you bring it with you into hospital.

What will the doctors do?

Your surgeon will discuss the risks and benefits of surgery and may suggest alternatives.

You should tell your anaesthetist if you snore heavily or have obstructed breathing during sleep. Depending on the type of operation, your anaesthetist may suggest a local anaesthetic, for example, a spinal, epidural or a limb block. This reduces or avoids the need for general anaesthesia.

The benefits include pain relief without the use of strong pain killers (like morphine) and improved postoperative breathing and mobility. However, spinal and epidural anaesthetics are technically more difficult in obese patients and may not always be possible.

Can I still be a day case?

Yes you may be able to have day surgery and go home straight after the operation. Where you stay after your operation depends upon the complexity of the surgery and any medical problems you may have.

After your operation

It’s important to get out of bed and walk around as soon as possible. In most cases, this will be within a few hours of surgery.

It’s vital you breathe deeply to reduce the risk of chest complications.