WHAT ARE THE RISKS?
Australia has an excellent safety record for anaesthesia. Anaesthesia risk is now extremely low in patients who are fit and well. Current research estimates that directly related anaesthetic mortality is around 1 in 50000. The majority of these deaths (>80%) occurred in older patients over 60 years old. In addition, >70% of anaesthesia-related deaths also occurred in emergency surgery where we are faced with the challenging combination of a unwell patient and less preparation time.
The Australian and New Zealand College of Anaesthetists has been carefully investigating and monitoring the quality and safety of anaesthesia for the last 30 years. Modern anaesthetic drugs and equipment are major contributors to safe anaesthesia but there is really no substitute for vigilant monitoring by a trained specialist. The possibility of serious complications such as death or permanent disability is very remote but we cannot afford to become complacent because it still exists even in a first world country with top level health care. In addition, certain patients will be at higher risk due to their medical condition, age, and/or the nature of their surgery.
It is not our intention to alarm patients but it is very important for you to understand the risk of anaesthesia so that you can make an informed decision about whether or not to have an anaesthetic.
1. COMMON RISKS OF GENERAL ANAESTHESIA:
- Bruising at injection site
- Nausea or vomiting
- Sore throat and voice hoarseness from anaesthetic breathing equipment or gases
- Temporary headache or dizziness
- Temporary blurred vision
- Temporary muscle pains
2. UNCOMMON RISKS OF GENERAL ANAESTHESIA:
- Awareness particularly during certain operations and emergency situations
- Eye abrasions
- Oral injury (teeth, dental work, tongue, lips, throat)
- Nerve injury - related to pressure or overstretch
3. EXTREMELY RARE BUT POTENTIALLY FATAL RISKS OF GENERAL ANAESTHESIA:
- Airway obstruction which can lead to severe breathing difficulty and lack of oxygen
- Severe allergic reaction (anaphylaxis)
- Inherited muscle sensitivity (malignant hyperthermia) - life threatening muscle rigidity, raised temperature, multiorgan failure
- Heart attacks
- Strokes
- Clots - deep vein thrombosis or pulmonary embolus
- Pneumonia and atelectasis (lung collapse) – especially in smokers and patients with pre-existing lung disease
- Aspiration - lung injury due to the regurgitation of stomach contents into the lungs
4. RISKS FOR ALL PATIENTS HAVING A PERIPHERAL NERVE BLOCK:
- Inadequate or excessive numbness
- Needle injury to nearby organs (e.g. lungs) and/or blood vessels
- Temporary muscle weakness in the anaesthetised limb
- Rare risk of nerve injury resulting in long term weakness, altered sensation, pain or paralysis
5. RISKS FOR ALL PATIENTS HAVING A CENTRAL NERVE BLOCK (SPINAL OR EPIDURAL):
- Common risks -
Bruising at injection site, incomplete/failed block requiring a conversion to a general anaesthetic, temporary itching, headache, backache, low blood pressure, and bladder and/or bowel problems
- Rare risks - infection or bleeding around the spinal cord which may require antibiotics and/or spinal surgery.
