Conscious sedation for surgical procedures

Conscious sedation is more accurately called moderate sedation. Medicines make you relaxed and sleepy during a procedure, but you should still respond purposefully when someone speaks to or gently touches you.

You usually breathe without a machine, although oxygen may be given. Your breathing, oxygen level, blood pressure, and heart rate are monitored.

Unlike general anaesthesia, sedation is not intended to make you fully unconscious. You may remember little because some sedatives affect memory, but complete sleep or amnesia cannot be guaranteed.

Sedation reduces anxiety and awareness but may not block pain. It is often combined with local anaesthesia or pain-relieving medicine.

Conscious sedation can make minor surgery, endoscopy, dental treatment, imaging-guided procedures, or bedside treatment easier to tolerate without general anaesthesia.

The intended depth depends on the procedure, expected discomfort, your health, and your ability to cooperate. Sedation supports the main procedure; it does not diagnose or treat a condition itself.

Moderate sedation may be suitable when a procedure does not require complete unconsciousness and can be performed while you breathe on your own.

A different plan may be safer for a long or especially painful procedure, or when you must remain completely motionless. Deep sedation or general anaesthesia may then be considered.

Sedation may be avoided, delayed, or adjusted if you have:

• A current breathing problem or unstable heart or circulation problem
• An allergy or serious previous reaction to a planned medicine
• Severe sleep apnoea or another condition affecting your airway
• Recently eaten or drunk before a non-urgent procedure
• Alcohol, opioid, sedative, or recreational drug intoxication
• No responsible adult to take you home when an escort is required

Pregnancy, frailty, obesity, or significant heart, lung, liver, or kidney disease require individual assessment. In an emergency, treatment may proceed despite issues such as recent eating, with extra precautions.

Follow your facility's instructions because fasting and medication rules vary by procedure and sedative.

You may need to stop eating several hours beforehand and stop clear liquids closer to the appointment. Do not assume that “nothing by mouth” has the same meaning for every procedure.

Tell the team about:

• All medicines, supplements, alcohol, cannabis, and recreational drugs you use
• Opioids like oxycodone or morphine, sleeping tablets, anxiety medicines, and other sedatives
• Blood thinners like warfarin or apixaban, diabetes medicines, and weight-management medicines
• Allergies, previous anaesthetic problems, sleep apnoea, or possible pregnancy
• Loose teeth, dentures, hearing aids, or difficulty opening your mouth

Do not stop a blood thinner or other prescribed medicine unless the treating team tells you to.

Arrange transport home if instructed. You will usually need a responsible adult to accompany you and may need them to stay afterward. Bring inhalers, a CPAP machine, or other equipment if requested.

Before sedation, a clinician reviews your health, medicines, fasting status, allergies, and previous experiences with sedation or anaesthesia. You can ask questions before giving consent.

An intravenous line, or IV, is often placed in a vein. Sedative and pain-relieving medicines are given in small amounts until the intended effect is reached. Some procedures use swallowed or inhaled medicine instead.

A finger clip measures oxygen, and a cuff checks blood pressure. Heart and exhaled carbon dioxide monitoring may also be used. Oxygen may be given through nasal tubes or a mask.

You may feel calm, drowsy, and less aware of time, but should still respond. Tell the team if you feel pain, pressure, nausea, or anxiety.

Sedation can become deeper than intended. The team must be ready to support your breathing and, when appropriate, give medicines that reverse certain sedatives or opioids.

Pain afterward usually comes from the main procedure. Follow its pain-management plan. Mild nausea, dizziness, headache, drowsiness, or patchy memory may occur.

You can usually eat and drink when alert and able to swallow safely, unless the procedure requires restrictions.

Rest for the remainder of the day. For the instructed period, avoid alcohol, recreational drugs, unapproved sleeping tablets, important decisions, legal documents, and activities requiring balance or coordination.

Do not drive yourself home. Follow the facility's exact restriction, commonly until the next day or for 24 hours. This may also apply to cycling, operating machinery, or cooking with heat.

Many people return to desk work the next day. Allow longer if you remain drowsy, had surgery, or work with driving, machinery, heights, or safety-critical decisions.

Sedation may slow breathing or allow the airway to become blocked, lowering oxygen levels. Staff may reposition your head, give oxygen, assist breathing, or provide more advanced airway support.

Other possible complications include:

• Low blood pressure or heart-rate changes
• Nausea, vomiting, dizziness, or prolonged drowsiness
• Unintended deep sedation or loss of responsiveness
• Stomach contents entering the lungs
• An allergic reaction
• Agitation or distress
• Bruising, pain, or infection at the IV site

Risk may be higher with sleep apnoea, serious heart or lung disease, frailty, or substances that slow breathing. Continuous observation and monitoring help detect problems promptly.

Sedation has no test result. Its effect begins during the procedure and gradually wears off.

The clinician may explain procedure findings soon afterward. Because sedation can affect memory, ask for written instructions and consider having your accompanying adult listen.

Laboratory or pathology results may take several days or longer. Your discharge information should explain how you will receive them.

Attend follow-up appointments for the main procedure even if your immediate recovery is uncomplicated.

Alternatives depend on the main procedure:

• Local anaesthesia alone: avoids sedative effects, but you remain fully aware and may feel more discomfort
• Minimal sedation: reduces anxiety while leaving you more alert, but may provide less comfort
• Regional anaesthesia: numbs a larger body area but is not suitable for every procedure
• Deep sedation: makes you less responsive, but breathing support is more likely
• General anaesthesia: keeps you unconscious and still but usually requires more airway support and recovery
• Delaying or declining the procedure: avoids immediate sedation risks but may delay diagnosis or treatment

Ask whether alternatives to the procedure include another treatment, a less invasive test, watchful waiting, or no procedure.

Contact the treating team if nausea, dizziness, unusual sleepiness, IV-site redness, or pain is not improving as expected.

Seek urgent medical advice if you have repeated vomiting, cannot keep fluids down, become increasingly confused, or are much harder to wake than expected.

Call emergency services for severe trouble breathing, blue or grey lips, chest pain, collapse, a seizure, or if you cannot be awakened. Follow the main procedure's emergency instructions about bleeding, fever, or worsening pain.

Will I be asleep?

You will usually be relaxed and sleepy but not fully unconscious. You should respond to speech or gentle touch, although you may drift in and out of sleep.

Can I drive home?

No. A responsible adult should take you home. Follow the facility's restriction before driving again, commonly until the next day or for 24 hours.

How painful is it?

Sedation reduces distress and may include pain medicine, but it does not always remove pain. Local anaesthesia is often added. Tell the team if you are uncomfortable.

Will I remember the procedure?

You may remember all, part, or none of it. Some sedatives cause temporary memory gaps, but complete amnesia cannot be promised.

When will I know the results?

Immediate findings may be discussed afterward. Tissue or laboratory results take longer. Get the information in writing because your memory may be affected.

What if I become fully unconscious?

Sedation can become deeper than intended. The team monitors you and must be able to support your breathing and manage deeper sedation.