Why can't I eat or drink before cancer surgery?
Because of a risk called aspiration. MedlinePlus explains that aspiration happens when food, liquid or other material is breathed into the airways or lungs instead of being swallowed, and that being less alert because of medicines or surgery is a risk factor. This can cause aspiration pneumonia, a serious lung infection. An empty stomach lowers the chance of this while you are under anesthesia.
The National Cancer Institute says you may not be able to eat or drink for a certain period of time before surgery. It is important to follow these instructions. If you do not, your surgery may need to be rescheduled.
How long you need to stop eating and drinking, and what counts, depends on your hospital and your operation. Use the exact times your own team gives you, not general rules you have read elsewhere.
Medicines are a separate question. MedlinePlus says you may be asked to stop taking blood thinners in the week before surgery, including some over-the-counter medicines and supplements such as aspirin, ibuprofen, naproxen and vitamin E. On the day of surgery, you take only the medicines your surgeon told you to take, with a small sip of water. Ask your surgeon which medicines to still take on the day of surgery. Diabetes medicines, insulin and blood thinners usually need their own instructions, so ask about each one. Do not stop or change a medicine unless your team tells you to.
If you ate or drank something you should not have, tell the team when you check in, even if it was small and even if it means waiting. It is their decision whether to go ahead.
Before surgery you may also be told how to prepare and about tests you need, such as blood tests, a chest x-ray, or an electrocardiogram (ECG).
Your surgical team will give you exact instructions about when to stop eating and drinking. If anything is unclear, ask them. Write down two clock times: the last time you may eat, and the last time you may drink. Keep them where you will see them the night before.
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Want the full picture? Read our complete explanation: What Is Surgery for Cancer?
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