01Purpose and principlesWhat the treatment does and how it fits into care.
Procedural sedation makes an otherwise difficult or painful intervention tolerable while seeking to preserve an appropriate level of responsiveness and physiological stability. The required depth depends on the procedure, patient and alternatives. A local or regional anaesthetic technique, reassurance or a different setting may provide a better balance of benefit and risk. The decision should address both the procedure and the means of making it possible.
Sedation is a continuum rather than a guarantee attached to a drug name. The same dose can produce different effects in a young healthy adult and a frail person who has already received opioids. Dose, speed, timing and combinations matter. A safe plan specifies who watches the patient, what signs will stop further dosing, how ventilation will be rescued and where recovery will occur.
Key points
- Sedation can become deeper than intended; the team must be able to recognise and rescue airway or cardiovascular compromise.
- Use a dedicated sedation clinician, a separate procedural clinician and a trained nurse in an appropriately equipped area.
- Assess the airway, physiological reserve, aspiration risk, prior drug doses and the procedure’s urgency before selecting an agent.
- Provide analgesia for pain: increasing a non-analgesic sedative does not correct inadequate pain treatment.
- Monitor ECG, oxygen saturation, blood pressure and continuous capnography alongside direct observation of breathing.
- Recovery requires stable physiology and return towards baseline function, with appropriate supervision and clear written advice.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
Assess mouth opening, dentition, neck movement, body habitus, sleep apnoea and previous airway difficulty. An apparently simple procedure can become dangerous if rescue ventilation or intubation is expected to be difficult.
Hypovolaemia, cardiac disease, respiratory impairment, frailty and acute illness increase the consequences of sedative-related hypotension or hypoventilation. Optimise reversible problems and seek senior or anaesthetic input before proceeding.
Define the intended response to voice or stimulation and whether the patient must remain still. Pain, anxiety and amnesia are different targets; choose analgesia and sedation deliberately rather than escalating one agent for every symptom.
Reduced respiratory effort, snoring, loss of the capnography waveform, falling pressure or unexpectedly deep unresponsiveness require immediate review. Oxygen can delay desaturation, so direct observation and ventilation monitoring are essential.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Focused pre-sedation assessmentFirst step - Why
- Establish suitability, consent and the safest setting.
- Interpretation and limitations
- Record relevant comorbidities, allergies, weight, baseline observations, prior anaesthetic problems and recent food, fluids and medicines. Routine laboratory testing is not a substitute for a focused clinical risk assessment.
- 02
Continuous capnography and oximetry - Why
- Observe ventilation and oxygenation during dosing, the procedure and recovery.
- Interpretation and limitations
- An absent waveform may reflect apnoea, obstruction or a disconnected sampling line. Look at the patient immediately and correct inadequate ventilation while checking equipment; do not await a saturation fall.
- 03
ECG and repeated non-invasive blood pressure - Why
- Detect cardiovascular effects and guide drug titration.
- Interpretation and limitations
- Compare with the pre-procedure baseline and consider pain, hypovolaemia and drug effect. A pressure fall after propofol may need interruption, circulatory support and reassessment of whether to continue.
- 04
Recovery assessment - Why
- Determine whether the patient can safely leave monitored care.
- Interpretation and limitations
- Check alertness, airway patency, baseline oxygen requirement, stable vital signs, pain and nausea control, and ability to tolerate fluids as appropriate. Complications or reversal-agent use require an extended, explicit monitoring plan.
04Treatment approachPreparation, options, escalation and aftercare.
01Worked caseA shoulder reduction interrupted by apnoeaFirst stepA healthy adult undergoing shoulder reduction has received titrated propofol with a separate sedation clinician present. The capnography waveform disappears and there is no visible respiratory effort, while SpO2 is still 98% on oxygen.+
- 1Treat the absent effort as apnoea. Stop propofol and pause the reduction immediately; ask for help while the sedation clinician maintains responsibility for the airway.
- 2Open the airway, use appropriate adjuncts and provide bag-mask ventilation with oxygen. Check the capnography line in parallel, but do not let an equipment check delay ventilating a non-breathing patient.
- 3Verify chest rise and a returning carbon dioxide waveform during assisted breaths. Continue until effective spontaneous ventilation and an appropriate conscious level return, watching blood pressure and rhythm.
- 4The patient resumes regular breathing without assistance. Reassess whether the procedure should continue under a revised senior plan, using the total drug exposure and complication rather than simply repeating the previous dose.
- 5Document the event, intervention and response, continue monitored recovery and review the sedation record. Confirm safe recovery criteria and appropriate aftercare before discharge.
02Preparation branchAn urgent procedure in a non-fasted patientAn adult requires urgent reduction of a painful dislocation and has eaten recently.+
- 1Assess urgency, aspiration risk, airway difficulty, comorbidities and available alternatives. Recent intake is relevant, but elective fasting rules should not automatically delay every emergency procedure.
- 2Discuss the planned technique and risks with the patient, involve an experienced decision maker, and ensure staff, suction, oxygen, ventilation equipment and rescue capability are ready before any sedative is given.
- 3Agree the analgesic and sedative plan, dose increments, monitoring and recovery arrangements in a team brief. Document the risk-benefit decision and change the setting if the required rescue capability is unavailable.
03Recovery branchPreparing to leave the departmentThe procedure is complete and the patient appears awake after sedation.+
- 1Continue monitored observation until breathing, circulation and cognition remain satisfactory without repeated stimulation, with no new oxygen requirement or uncontrolled pain or nausea.
- 2Review any complication, repeated dosing or reversal agent and extend observation accordingly. A brief response to flumazenil or naloxone can be followed by recurrent sedation.
- 3Confirm suitable accompaniment and care at home, provide the unit’s written driving, alcohol, machinery and decision-making restrictions, and ensure procedure-specific follow-up is understood.
05Regimens, contraindications and interactionsTreatment details and the circumstances that modify them.
Propofol for adult procedural sedation
The UK 1% product describes 0.5–1 mg/kg IV over 1–5 minutes for onset, titrated to response. RCEM recommends substantially smaller, slowly given 10–20 mg increments in older adults; allow effect before additional dosing.It provides no analgesia and can cause apnoea and hypotension. Reduce dose and speed with frailty, poor cardiac reserve or prior opioids; stop dosing at excessive depth or physiological compromise. Check product-specific allergy contraindications.
Midazolam for conscious sedation
Using 1 mg/mL injection, the UK SmPC starts adults under 60 at 2–2.5 mg IV, given slowly, with 1 mg increments if needed. In older, debilitated or chronically ill adults start 0.5–1 mg and titrate cautiously in 0.5–1 mg increments.Allow time for the evolving effect; the SmPC places initial administration 5–10 minutes before the procedure. It is not an analgesic. Opioids, renal or hepatic impairment and respiratory disease increase risk of prolonged or excessive sedation.
Ketamine for adult dissociative sedation
RCEM lists 1 mg/kg IV over 30–60 seconds in adults, with 0.25–0.5 mg/kg increments at 5–10-minute intervals when necessary. Use reduced individual doses in older or vulnerable patients.Preserved airway reflexes are not guaranteed. Laryngospasm, vomiting, emergence symptoms and cardiovascular effects require trained monitoring and rescue capability; follow the patient-specific and product contraindications.
06Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- Maintain direct observation with ECG, oximetry, capnography and repeated blood pressure from drug administration through the period of clinically significant sedation and recovery.
- Record each medicine, actual dose and time, the observed depth and any airway or haemodynamic intervention so that cumulative exposure can be assessed.
- After an adverse event, reassess the patient and the whole sedation plan before continuing; monitor longer where drug duration, repeated dosing or reversal creates a recurrence risk.
- Before discharge, verify return to baseline physiological requirements, suitable support and understanding of written advice; record the clinician or protocol responsible for the decision.
07Special situationsVariants, exceptions and circumstances that change the usual approach.
Concentration errors are preventable
For conscious sedation, select the intended low-strength midazolam preparation and label the syringe clearly. Confusing milligrams with millilitres can turn an apparently small volume into a large dose.
Local anaesthesia can reduce systemic dosing
A well-chosen local or regional technique may reduce pain and the amount of systemic sedation required. Its own contraindications, dose limits and rescue requirements still need assessment.
Consent precedes sedation where possible
Explain alternatives, expected sensations, material risks and recovery restrictions while the person can participate. In an emergency involving incapacity, follow the applicable legal framework and document why immediate treatment is necessary.
Recovery space is a prerequisite
A completed procedure does not free the team from observation duties. Confirm sufficient staff and a suitable recovery area before starting so another emergency does not leave a sedated patient unattended.
08Common pitfallsFrequent interpretation and management errors.
- 01
Do not ask one clinician to perform the procedure while also being the sole person responsible for parenteral sedation and monitoring.
- 02
Do not repeat a sedative rapidly because the full effect has not yet appeared, particularly after opioids or in a frail patient.
- 03
Do not interpret a normal saturation on oxygen as proof that ventilation remains adequate.
- 04
Do not use a reversal agent as a shortcut to discharge or a substitute for correcting an obstructed airway and inadequate breathing.