Risks from anaesthesia

This page does not contain a comprehensive list of all risks involved with anaesthesia. Your anaesthetist will meet with you before your operation, to discuss risks, and to perform an assessment. Depending on the type of operation, hospital or facility, this may not occur until immediately beforehand. Although anesthesia is generally very safe, risks do exist. The risk of a heathy person dying unexpectedly is less than the risk of dying in a car accident. However, risks exist which are usually temporary, but some may cause long term problems.

Common unwanted and temporary side effects
  • nausea or vomiting
  • headache/dizziness
  • pain/bruising at injection sites
  • sore throat/lips
  • blurred/double vision
  • short term memory loss
Less common unwanted and temporary side effects
  • muscle aches and pains
  • weakness
  • itching/rash
Uncommon unwanted side effects
  • awareness under anaesthesia
  • damage to teeth, dental prosthetics and lips
  • difficulty breathing; pneumonia
  • damage to ‘voice box’
  • allergic reactions/asthma
  • epileptic seizures
  • damage to nerves; eye injury
  • nerve damage is an additional specific risk with local anaesthesia which is usually mild and temporary, but rarely, it can be severe and permanent causing paraplegia or quadriplegia.
Rare risks that may cause death
  • severe allergy or shock
  • very high temperatures
  • stroke or heart attack
  • vomit in the lungs (aspiration)
  • brain, kidney, liver, lung injury
Conditions which increase risks under anaesthesia
  • advanced age
  • bad cold/flu; asthma; smoking
  • being overweight
  • diabetes
  • heart disease
  • high blood pressure
  • other serious medical conditions