Anaesthesia, Sleep & Sleep Apnoea

This is a fact sheet about Anaesthesia, Sleep & Sleep Apnoea. People who have sleep apnoea are at risk of their throat blocking when sedated or under anaesthesia, just as can happen during sleep.

Woman asleep wearing CPAP mask. Image by on Freepik.
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January 12, 2024
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Things you should know:

  • Anaesthesia and sleep affect breathing and upper airway function in similar ways.
  • Patients with Obstructive Sleep Apnoea (OSA) can also have trouble breathing when under or recovering from anaesthesia.
  • Let your anaesthetist know if you have OSA.
  • Your anaesthetist will look after your breathing and make sure no problems develop, and also set up special care for you after surgery.
  • If you use sleep apnoea treatment at home, you must take your pump and mask or other treatment with you to hospital.

How are sleep and anaesthesia the same? How do they differ?

Sleep is natural.  When you have met the need for it, it will finish by itself. Anaesthesia is caused by drugs. It will only finish when the drugs wear off.  These drugs work by acting on the same parts of the brain that control sleep.  Both anaesthesia and sleep reduce your breathing efforts.  They also cause your muscles, including throat muscles, to relax.  Because of these changes there is a risk of under-breathing or blocking of the throat in both sleep and anaesthesia.

What problems can OSA cause during anaesthesia? What about after?

People who have Obstructive Sleep Apnoea (OSA) are at risk of their throat blocking when sedated or under anaesthesia, just as can happen during sleep.   This situation is worse with sedation and anaesthesia because they interfere with the ability to respond to the blocking by arousing or waking up.  Anaesthetists can best cope with this if they know you have or might have OSA.  Your anaesthetist will be with you throughout your operation to look after you, and there are extra options to deal with OSA. These include special anaesthesia methods, a longer period of close monitoring after surgery and applying CPAP when you are sedated or asleep.

What should I tell my anaesthetist prior to the surgery?

Anaesthesia and surgery can affect many body functions. Thus, your anaesthetist needs to know about any health issues which could affect your wellbeing when you have surgery.  You will meet your anaesthetist before the surgery to discuss these matters.

OSA can create special problems.  If you have OSA, or think that you might have it, be sure to let your anaesthetist know before your surgery.

There are other issues that you normally talk about before the surgery e.g. previous illnesses (such as recent problems with your lungs or throat), smoking, any drugs you may be taking (both legal and illicit, as well as herbal and alternative treatments), how much alcohol you drink, allergies (to drugs and dressings), previous problems with anaesthesia(including postoperative nausea and vomiting and postoperative pain), a family history of anaesthesia problems and pregnancy or the possibility of it.

How do I get ready for surgery? 

You should learn about the surgery you are having. You need to know what it will do for you, as well as the risks.  This includes the care plan for after the operation, including pain relief. Unless it is an emergency, you should fast before the surgery according to the instructions you are given.

What should I do about my CPAP therapy?

If you use CPAP or other treatment for sleep apnoea, you must let your anaesthetist know.  If you are using CPAP, your familiarity with it is helpful as it makes it easier to apply after the operation.  Bring your equipment with you on the day of your admission.  You should know your pressure settings and mask type. This is in case hospital equipment needs to be used.

Where can I find out more?

Download a PDF of this Fact Sheet

Other useful links: