Some people become confused after an operation and anaesthetic. In some cases their memory may fail, in other cases their behaviour is quite unlike their normal selves. This can be very upsetting, both for the patient and their friends and family. While confusion can occur at any sage, it is more likely in older patients and in those with a history of confusion. The good news is that the majority of patients recover fully, with no long- standing confusion.

How does Confusion present itself?

Confusion after an anaesthetic can present in many ways. Some people become agitated and confused in their thinking while others become quiet and withdrawn.

Typical examples include:

  • Not knowing your name or where you are
  • Not knowing what has happened to you or why you are in hospital
  • Loss of memory- you may be unable to recognise family members
  • Reversal of day and night sleep pattern
  • Being illogical, incoherent, shouting and swearing.
  • Emotional changes such as anxiety, tearfulness,and aggression
  • Trying to climb out of bed and appearing indifferent to whatever is going on.
  • Becoming paranoid and thinking that people are trying to harm you
  • Occasionally, people may experience visual or auditory hallucinations.

Why does this happen?

In the first few days and weeks after your operation, your body is repairing itself and the physical challenges associated with this process may cause you to be confused. In this situation, time is the best cure for the confusion. However, there are some treatable causes of confusion, these can include:

  • Infections
  • Poor pain control or side effects of pain relief medicines
  • Dehydration and inadequate nutrition
  • Low oxygen levels due to aftereffects of the anaesthetic, effects of medicines on breathing or other lung problems
  • Loss of vision and hearing, simply due to lack of glasses or hearing aids
  • Sleep disturbance is a common trigger for confusion.
  • Constipation, which is sometimes triggered by the pain medication that we use after an operation, can make confusion worse
  • Medications are a common cause;, both new medications regular medications that have been changed or omitted.

How likely am I to get confused?

The following factors increase your chances of becoming confused:

  • Advanced age
  • Previous ill health
  • Previous poor memory, dementia, stroke, and other brain disorders like Parkinson’s disease
  • Previous high alcohol intake
  • Previous poor mobility

Does the type of anaesthetic make a difference?

Yes, you can reduce the risk of confusion by opting for local or regional anaesthetic. We can also adjust the type of general anaesthetic to lower your risk of confusion.

I will always tailor the anaesthetic to your individual risk and underlying conditions. While we will do everything possible to lower your risk of confusion, it still may occur despite our best efforts.

How is it treated?

The good news is that majority of people with confusion make a full recovery. If there are any treatable reasons for the confusion, they will be addressed and hopefully the confusion will
improve. Sometimes it takes a little while after starting treatment for the confusion to improve. (e.g. antibiotics, oxygen, pain relievers, fluids etc.)

If there is not a treatable cause identified, the following measures can be helpful:

  • Frequent reassurance and reorientation are important for recovery. The involvement of family, friends and even pets can help to reassure you that you are safe.
  • Use of familiar objects such as your own pillows and clothes helps
  • Use of clocks and calendars are helpful to keep track of time
  • Making sure that glasses and hearing aids are available immediately after surgery.
  • Use of an interpreter for non-English speakers
  • A return to normal sleep pattern and normal eating and drinking should be encouraged.

Despite these measures, some people may need sedatives (calming medicines) if they are at risk of harming themselves or others due to confusion.

How long does it take to recover?

Most people recover within days, especially if a treatable cause is identified. In some cases, the confusion after an operation lasts for longer, this is often in people have a history of confusion or memory problems. If the confusion lasts for more than 3 months, it is termed post-operative cognitive dysfunction (POCD). If this were to develop, you would be referred to a physician to assist with your recovery.

What is POCD?

In addition to feeling generally confused, some people, especially those over 60, find that their higher mental functions are not quite as good as they were before the operation and anaesthetic. e.g. cannot do the crossword or complex calculations as easily. These changes are called POCD and can be noted at one week (early) or 3 months or more after an operation (late). The cause of POCD is not quite understood just yet. POCD is detected in clinical trials by memory tests, mood assessments and tests of ability to manage activities of daily living. Experts disagree on the validity of these tests and on how the results should be analysed. If you think you may have POCD it is important that you visit your GP and talk about it.