Confusion in the first days after an operation is usually delirium. It is common, and it often improves as the person recovers from the surgery.
Delirium after surgery is called post-operative delirium. It usually starts a day or two after the operation.
After heart surgery it affects around 1 in 4 people, and about 1 in 5 in some centres. It is more common still after emergency surgery, such as an operation for a broken hip.
Why it happens
Usually more than one thing is involved: the strain of the operation itself, the anaesthetic, pain, painkillers such as morphine, infection, dehydration, constipation, low oxygen levels and broken sleep. The team should work through that list and treat whatever they find.
What you can do
Bring her glasses and hearing aids. Sit with her and talk about ordinary things. Help with food and drink if staff say it is safe.
And tell the staff how she is compared with her normal self. You know that better than anyone on the ward. There is more about how families can help.
If nobody has used the word delirium and something seems wrong to you, say what you have noticed and ask: could it be delirium?
How long it lasts
Most post-operative delirium settles over days as the causes are treated. In some people it takes weeks. That is more likely in older people who were already frail.
If it is not clearing, ask the team what causes they have found, and what they are still looking for.
When to get help
New confusion that has come on over hours or days needs medical advice the same day. Phone the GP practice, or 111 when it is closed. Phone 999 if the person cannot be woken, has collapsed, or has new weakness or new trouble speaking. When you speak to someone, say what has changed. Then ask: could it be delirium?