Common Misconceptions

SURGEONS

It's better that my patients starve than my theatre list be delayed, just because a patient has not fasted.

Your patients will not be delayed by drinking Dex.

Dex is safe to have 2 hours before anaesthesia.

The benefits of being in the “fed” state should not be trivialised.

Your patients will have a better theatre experience, your outcomes will be better and as a result your patients will be more satisfied.

PATIENTS

1. What is all the fuss about? Fasting is not a big deal.

Surgery is comparable to an endurance event such as a triathalon. Patients should have energy on board in the form of complex carbohydrates to be “event” ready. It is unwise for an athlete to enter an endurance event without eating or drinking for 6 hours beforehand, yet this is exactly what many patients currently do. Consuming Dex 2 hours before a procedure will provide the fuel that will benefit both your surgery and recovery.

 

2. I want my stomach to be really empty before an anaesthetic. Isn’t it good not to eat or drink?

The stomach is actually more empty 2 hours after drinking than if a patient starves for 6 hours. Clear fluid entering the stomach stimulates gastric emptying.

 

Negative effects of fasting for prolonged periods:

  • Dehydration

  • Insulin resistance

  • Electrolyte imbalances

  • Nausea

  • Vomiting

  • Irritability

  • Confusion

  • Difficult IV cannulation

 

3. I just want water. Isn’t water just as good as maltodextrin?

Drinking water up to 2 hours before surgery will not optimise your body.  A calorie-rich drink is necessary for achieving the following benefits:

  • Preventing catabolism and subsequent hyperglycaemia, loss of fat and protein stores, insulin resistance, and overall surgical trauma

  • Preventing hunger

  • Nourishing the body to prevent a 'starved state'

  • Maintaining an alkaline pH in the body

  • Facilitating an early recovery

 

4. Isn’t a sport drink just as good. I have easy access to them?

  • Sports drinks have not been shown to stimulate a “meal like” insulin response

  • Sport drinks have not demonstrated prevention of insulin resistance after surgery

  • Sport drinks are high in simple sugars such as sucrose and fructose

  • 50g of Maltodextrin has been investigated extensively in clinical trials

  • Hyperinsulinaemic – euglycaemic clamp studies show maltodextrin can prevent insulin resistance after an operation

  • Dex is formulated specifically for surgery, and is alkaline. Sport drinks are formulated for sports and are acidic.

  • ANZCA college guidelines does not mention sport drinks should even be considered prior to an operation. They state “consideration may be given to provision of clear carbohydrate-rich fluids, specifically developed for perioperative use”. Sports drinks do NOT fit into this category due to the high osmolality, low pH and inadequate maltodextrin.