Fasting Before Shoulder Replacement Surgery

Fasting for this procedure

Your shoulder replacement is done under a general anaesthetic, very often alongside an interscalene nerve block that numbs the entire arm and shoulder for several hours after surgery. Because you will be fully asleep, your stomach must be empty so nothing can come up into your lungs. Stop eating solid food, milk and milky drinks about 6 hours before your arrival time, and stop chewing gum and sweets by then too. You may keep sipping clear fluids (water, black tea or coffee, clear apple juice or squash) until 2 hours before arrival, which actually helps you feel better and recover faster. After that 2-hour point, take nothing by mouth except the small sip of water needed for any tablets your team has told you to keep taking. If your operation is scheduled for the afternoon, the same 6-hour and 2-hour rules apply counting back from your given arrival time, so you can usually have an early light breakfast.

Medicines to check

Blood thinners need a plan. Drugs like warfarin, apixaban, rivaroxaban or clopidogrel raise bleeding risk during a shoulder replacement and are usually paused for several days beforehand. Never stop them on your own - follow the dates on our medications to stop before surgery guide and your surgeon's instructions.

Diabetes medicines change on the day. Tablets and insulin often need adjusting while you are fasting to avoid low or high blood sugar. See diabetes tablets before surgery and confirm your exact plan with the team.

Keep taking most heart and blood-pressure tablets with a tiny sip of water on the morning of surgery, unless told otherwise - but ask specifically about ACE inhibitors and water tablets (diuretics), which are sometimes held.

Anti-inflammatory painkillers such as ibuprofen or naproxen may be stopped a few days before to reduce bleeding and bruising - check whether yours need pausing.

Bring a full list of everything you take, including inhalers, patches, herbal remedies and supplements like fish oil, as some affect bleeding or your anaesthetic.

If you take steroids or strong opioid painkillers regularly, tell the team early - these are not stopped but your doses and pain plan need adjusting around surgery.

When this surgery may be delayed

A chest infection, heavy cold or COVID symptoms in the days before surgery - a general anaesthetic on inflamed lungs is risky, so it is safer to postpone.

Any skin problem over the shoulder, such as a graze, rash, infected spot or active eczema, because a break in the skin near a new metal joint sharply raises the risk of a deep implant infection.

Eating or drinking inside the fasting window - if you have solids too late, your operation will be delayed or moved to protect your airway.

Blood thinners that have not been stopped at the right time, or blood tests showing your clotting or haemoglobin is not yet safe for joint surgery.

Poorly controlled blood sugar, blood pressure, or a new heart or breathing concern picked up at your pre-op check that needs sorting first.

Reports & documents to carry

Your admission letter and any pre-assessment paperwork or fasting instructions you were given.

A complete, up-to-date list of your medicines and allergies, plus the tablets themselves in their boxes if asked.

Recent test results, X-rays or scans of the shoulder, and any blood-thinner clinic card or anticoagulation plan.

A loose, button-up or zip-front top with a wide armhole - you will leave with your arm in a sling and cannot pull clothing over your head.

Your glasses, hearing aids, inhalers, a phone charger and an overnight bag, as most people stay 1 to 2 nights.

What to ask your anesthesia team

Will I have an interscalene nerve block as well as the general anaesthetic, and how many hours will my arm stay numb and weak afterwards?

When exactly should I take my next dose of pain relief, since the block can wear off suddenly during the night?

How long must I wear the sling, and can I take it off to wash, dress or do my exercises?

When does physiotherapy start, and which arm movements must I avoid in the first few weeks to protect the new joint?

Which of my regular tablets do I skip, and which do I take with a sip of water on the morning of surgery?

Your prep checklist

Tick things off as you sort them — saved on this device only, nothing is sent anywhere.

A general guide — your hospital's own instructions always come first.

Frequently asked questions

What is the nerve block and why is my whole arm numb?

An interscalene block is an injection of local anaesthetic near the nerves at the side of your neck that supply the shoulder and arm. Given with your general anaesthetic, it provides excellent pain relief for several hours after surgery. Your arm will feel heavy, numb and weak - this is normal and temporary. Keep it supported in the sling, protect it from knocks, and start your prescribed painkillers before the block fully wears off.

How long will I wear the sling and when can I use my arm?

Most people wear a sling for around 3 to 6 weeks to protect the repair while healing begins, though your surgeon sets your exact time. You can usually use your hand, wrist and elbow for light tasks early on, but you must avoid lifting, reaching behind your back or forcing shoulder movement until cleared. Follow the specific movement limits your surgeon gives you, as these vary with the type of replacement performed.

When does physiotherapy start after a shoulder replacement?

Gentle physiotherapy often begins within a day of surgery, while you are still in hospital, starting with simple supported movements and exercises for your hand and elbow. A structured programme then continues for several weeks to months to rebuild movement and strength safely. Sticking to your exercises is one of the biggest factors in a good result. Doing too much too soon, however, can damage the repair, so always work within the limits your team sets.

How long will I stay in hospital and can I drink before going home?

A typical stay is 1 to 2 nights, mainly so your pain, wound and arm can be checked and physio can get you started. Once your nerve block wears off enough to feel your hand safely and your pain is controlled on tablets, you can usually go home. You can eat and drink normally soon after surgery as the anaesthetic wears off - start with sips of water and light food, then build up as you feel ready.