'Nil by mouth' does more harm than good - expert

Expert calls for a review of the guidelines restricting solids and liquids before anaesthesia. Photo / Thinkstock

Subjecting patients to "nil by mouth" before surgery can do more harm than good to their recovery, says an anaesthetist.

Dr David Rowe has called for a review of the guidelines restricting solids and liquids before anaesthesia, which he says sometimes means patients are excessively "starved".

The guidelines were oversimplified and poorly followed, he told a meeting of the Australian and New Zealand College of Anaesthetists in Tasmania on the weekend.

"It is customary practice for the patient to be told not to eat solids for six hours before an operation to minimise the hazards of anaesthesia-induced vomiting and aspiration (inhaling stomach fluids into the lungs)," he said.

"But in practice this often ends up exceeding 12-18 hours."

As well as causing unnecessary discomfort, a prolonged nil by mouth period depletes a patient of the energy needed to aid recovery.

They should be allowed to drink clear, but calorie-rich, drinks up to two hours before their anaesthetic, Dr Rowe said.

"If you are about to run a marathon you wouldn't have a light meal the night before and then skip breakfast - major surgery compares to running a marathon in terms of the pressure on the body."

Patients reported less hunger, thirst, headache and nausea on arrival in operating theatres when allowed carbohydrate-rich fluids two hours before anaesthesia, he said.

"Let's not starve patients excessively - carbohydrate drinks taken two hours pre-operatively make the anaesthetic safer and will improve recovery as well as make the patient's experience more pleasant."

- AAP