Adult Conscious Sedation Policy

Publication: 01/05/2010  
Next review: 06/03/2023  
Clinical Guideline
ID: 2109 
Approved By: Trust Clinical Guidelines Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2020  


This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

Conscious Sedation in Adults

  1. Aims
  2. Objectives
  3. Background
  4. Management of procedure
  5. Safe use of Sedation Drugs
  6. Governance and Training
  7. Provenance
  8. Evidence Base
  9. Appendix

1. Aims

To set standards for the safe provision of Conscious Sedation for adult patients undergoing procedures in LTHT.
The term “conscious sedation” (also recognised as “Moderate” sedation) is used to describe a procedure where the sedated patient remains conscious, retains protective reflexes, and is able to understand and respond to verbal commands. Procedures requiring deeper levels of sedation/anaesthesia require the same standards as a general anaesthetic and are NOT covered by these guidelines.

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2. Objectives

To ensure that :

  • All adult patients referred for conscious sedation undergo a process of assessment to ensure that the use of sedation is appropriate, and that they are fit to undergo the procedure.
  • Adult patients who are at a higher risk of complications, are identified, and undergo additional clinical assessment and monitoring as outlined.
  • Adult patients undergoing conscious sedation are observed and monitored at regular intervals during the procedure and in the recovery phase by a designated TRAINED practitioner. This person must not be the operator (the person carrying out the procedure).
  • A defined range of equipment and techniques for patient monitoring and managing emergencies are available whenever a patient receives conscious sedation.
  • The medicines and doses used for conscious sedation carry a margin of safety wide enough to render loss of consciousness unlikely, hence minimising the risk of adverse events. Operators must use the minimum effective dose and take particular care when sedating the frail or elderly. Further Information on medicines are outlined in this guideline.
  • The reversal agent flumazenil must be available wherever conscious sedation is administered but its use should be minimised. Units must monitor for excessive use of flumazenil by regular QA/audit or (where this is not feasible) by completing a Datix report each time it is used. 
  • All users of sedation, irrespective of educational background, should undergo competency training in the use of sedation and management of potential adverse events. This should be done within their specialty.

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3. Background

Sedation for diagnostic, investigative and therapeutic procedures is becoming increasingly common. The use of sedation to alleviate anxiety and reduce pain makes these procedures more acceptable to patients, but has the potential to cause life-threatening complications if performed incorrectly. The trust needs to ensure that standards are set and followed to minimise the risk of adverse incidents occurring.

Sedation is a continuum from the awake state to general anaesthesia, and is described by the American Society of Anaesthesia as 4 stages; Minimal sedation, Moderate/”Conscious” sedation, Deep sedation and General Anaesthesia  - see appendix The ASA definitions of sedation for further details.

Conscious/Moderate Sedation is defined as a drug induced depression of consciousness, during which the patient can respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. Spontaneous ventilation and airway reflexes are maintained, hence intervention to maintain a patent airway should not be required. Cardiovascular function is usually maintained.

Current published guidance on sedation practice is based on expert opinion from consensus documents and high quality audit, recognising the lack of evidence from randomised trials. This document was first written in response to the NPSA alert in 2008 described below, and has been updated every 4 years in accordance with recommendations made by the following bodies;

  • United Kingdom Academy of Medical Royal Colleges and their Faculties, latest document 2021 (1,7,12)
  • Royal College of Anaesthetists Guidelines for the Provision of Anaesthetic Services (8)
  • Association of Anaesthetists Recommendations for monitoring 2021 (11)
  • National Patient Safety Agency (2)
  • The British Society of Gastroenterology (3,4)
  • American Society of Anaesthesiologists (9)

In December 2008 the National Patient Safety Agency published a rapid response alert “Reducing risk of overdose with midazolam injection in adults” (2). This document required all NHS and independent Hospitals to adopt a range of strategies to minimise the risk of adverse events associated with the use of conscious sedation in adults in the UK.  It recommended the use of low strength midazolam only, having therapeutic protocols, auditing flumazenil use as a marker of excess midazolam use, ensuring practitioners receive training, and that sedation is covered by an Organisational Policy. Following on from this alert NHS England classified any situation where a patient receives an overdose of midazolam, due to incorrect use of a high strength product (>1mg/ml), as a “Never event”.(6)

The document from The Academy of Medical Royal Colleges “Safe Sedation Practice for Healthcare Procedures Standards and Guidance”  published December 2013 found that a common recurring theme is lack of training. They recommended that it is the responsibility of each specialty using sedation to ensure their trainees have accredited training to a nationally defined standard, and that Royal Colleges should define the standards within approved post graduate training curricula.

Audit of process and outcomes of procedures performed under sedation should occur within each specialty. They recommended the establishment of a sedation committee to support implementation of these recommendations. This is in line with recommendations made by the UK Anaesthetic Accreditation Services in 2019, based on The Royal College of Anaesthetists (RCoA) Guidance for Anaesthetic Services.

The RCoA does not provide recommendations for sedation given by non-anaesthetists, practitioners are encouraged to follow the guidance of their own Institution, Specialty College’s and the Academy of Medical Royal Colleges. However they do provide guidelines for anaesthetic services in Non-theatre Environments which made the following recommendations in 2019:

  • A named Anaesthetist should be responsible for liaising with Consultants in other departments with responsibility for sedation, and to establish local guidelines and training for the provision of safe sedation by non-anaesthetists.
  • Each facility should develop written policies, designating the types of operative, diagnostic and therapeutic procedures requiring anaesthesia or sedation.
  • Guidelines for the management of rare emergencies must be prominently displayed at all sites where sedation is administered.
  • Midazolam over sedation (due to mis-selection of high strength solution) is defined as a ‘never event’ by the Department of Health.65 Hospitals should report these incidents to the National Reporting and Learning System.
  • All institutions where sedation is practised should have a sedation committee. This committee should include key clinical teams using procedural sedation and there should be a nominated clinical lead for sedation. In most institutions, the sedation committee should include an anaesthetist, at least in an advisory capacity.

There have been 2 further documents published this year, 2021, by the Academy of Medical Royal Colleges and the Association of Anaesthetists. The AOMRC published an Update to re-emphasise the importance of Sedation Governance and Training, and revise its guidance in-line with other authoritative national guidance on procedural monitoring standards. The Association of Anaesthetists have made the same recommendations for Sedation standards.

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4. Management of procedure

4.1 General principles

When selecting a suitable technique it should be remembered that the principal aims of Conscious sedation are to provide sedation and relieve anxiety, maintain consciousness and patient cooperation, and maintain control of physiological parameters (7). 

The following form an essential part of the Care Pathway of all Adult patients undergoing planned procedural conscious sedation:

  • Pre-procedure assessment
  • Information and Consent
  • Fasting requirements
  • Standards for Facilities and Equipment
  • Monitoring and procedural standards required
  • Safe use of appropriate sedation drugs
  • Management of complications
  • Post-procedure care and discharge
  • Audit and Training

Depending on local circumstances and skill mix, the roles and responsibilities of the operator and the sedation practitioner may be merged, but the guiding principles are:

1.There should be a minimum two person team - The operator is never responsible for monitoring the patient during the procedure. (They may prescribe and administer drugs prior to commencing the procedure but another trained assistant is required to monitor the patient.)

2. If an assistant is required for the procedure itself, this should be a third person and not the person monitoring the patient.

3.The patient must be under continuous observation by a member of this team from the onset of sedation until they are fully recovered.

3. A record of assessment, consent, medicines given, and observations must be recorded in the patient’s medical case notes.

4. At least one individual capable of establishing a patent airway, providing positive pressure bag mask ventilation, and chest compressions if required, must be present in the procedure room. This correlates with ILS (intermediate life support) skills level.

5. All practitioners should be able to recognise the need for additional support and know how to access this from their department. If support is required, an individual with Advanced Life Support skills (ALS - tracheal intubation/LMA insertion, defibrillation, use of resuscitation medications) should be available for emergency adverse events (This may be the Hospital Resus team attending within 5 minutes on main sites). If the procedure is undertaken on an isolated site, (without a resus team available) it is recommended that at least one of the team, operator or sedationist, is ALS trained.

6. All staff involved should take part in regular training, updates and resuscitation practice. This is particularly important for those working on isolated sites.


4.2 Pre-Procedure Assessment

Clinicians administering sedation/analgesia as part of a conscious sedation regime,

should be familiar with all relevant aspects of the patient’s medical history that might alter the patient’s response to sedation/analgesia. Inadequate pre-assessment is a recurring factor contributing to adverse sedation events.

A process of assessment using the American Society of Anesthesiologists ASA Score (see Appendix 1) should be applied to all patients referred for any treatment requiring conscious sedation.

This information may be obtained by asking the patient to complete a ‘check list’, preferably assisted by attendant staff. The level of detail required will depend on the procedure and the patient’s general condition, but the following information must always be included

  • Present Medical history and indication for the procedure
  • Past Medical History including Obstructive Sleep Apnoea Syndrome
  • Previous adverse experience with sedation/analgesia and with or general anaesthesia
  • Airway assessment (see below)
  • Focused physical examination if indicated
  • Drug allergies, current medications, and potential drug interactions
  • Fasting status
  • History of tobacco, alcohol, or substance use
  • Body Weight and baseline vital signs
  • Confirmation of suitable arrangements for escort and transport post-procedure for elective outpatients.

The airway should be assessed for difficulty. This may include any history of previous difficult intubation, the Mallampati airway score, lower jaw protrusion, neck flexion and extension, and mouth opening.

Any patient who is found to be at greater medical risk i.e. ASA Score 3 or above, may require a more detailed assessment and will require additional monitoring (see below) during the procedure. Pre-procedure laboratory testing should be guided by the patient’s underlying medical condition and the likelihood that the results will affect the management.

Anaesthetic input should be sought if potential airway problems are identified, which may compromise airway management, or the ability to ventilate the patient. Patients who score ASA 4 may (depending on practitioner experience) require discussion with an anaesthetist.

4.3 Patient Information and consent

In the case of elective outpatients or day-case procedures, instructions on activities before and after the procedure should be provided in advance and include guidance on

  • Fasting prior to the procedure (2 hours clear fluids, 6 hours solids - as per LTHT guidelines for general Anaesthetic)
  • Reporting acute illness and continuing regular medicines before the procedure.
  • Specific advice on diabetic drugs or anticoagulants.
  • Requirement for supervision by a responsible adult after the procedure
  • The need for an escort when travelling home
  • Guidance to avoid alcohol, any other sedative drugs, driving, and operating machinery for 24 hours after the procedure

The patient should be informed of the risks, benefits and alternatives to sedation as part of the consent process, documented on a standard Trust procedure consent form. The nature of sedation, with an explanation of the intended benefits of alleviating anxiety and pain, should be portrayed such that the patient’s expectations are clear. The fifth National audit Project (NAP 5) on accidental awareness during general anaesthesia, revealed that failure to provide patients with sufficient information such that they understand the nature of sedation, lead to excess patient reporting of awareness. It should therefore be emphasised to the patient that they may be awake, may have recall, and that sedation is not general anaesthesia.

NAP5 recommend describing the level of sedation from a patient’s perspective. (Appendix 5.)

4.4 Fasting

Fasting is controversial. Some authorities consider fasting unnecessary for conscious sedation as airway reflexes should be maintained, however there is the risk of inadvertent over sedation, at which point airway reflexes may be lost. Therefore, it is safer to fast patients requiring IV sedation as per GA guidelines (6 hours for solids, 2 hours for clear fluids). This is the recommendation of the AOMRC.

Fasting is not required with Entonox (nitrous oxide/oxygen). For emergency procedures in non-fasted patients, the decision to proceed with conscious (not deep) sedation should be a risk benefit decision. See National ED guidelines (9) for further detail.

4.5 Facilities and Equipment Required During Conscious Sedation

The vast majority of conscious sedation procedures occur in areas that perform this technique routinely. Facilities in these areas should be purpose built with allocated spaces for pre-assessment, for sedation/procedure, and for recovery. The procedure rooms should be large enough to accommodate all appropriate personnel and monitoring equipment, including a resus team should they be required.

A smaller number of one-off procedures will take place in other clinical settings. These areas are unlikely to be purpose built but must still have the same equipment/facilities before the procedure is undertaken. For sedation in MRI, where resuscitation close to the magnet would be dangerous, there should be an appropriately resourced adjacent area, and the team should practise regular transfer emergency drills.

All equipment and facilities must be checked daily or immediately prior to a procedure.

Facilities undertaking conscious sedation must possess:

  • An adult resuscitation trolley, including an automated defibrillator, stocked in accordance with the LTHT Resuscitation and Training Department’s Standard Adult Resuscitation Equipment List (available on the intranet)
  • Oxygen - a reliable source which will deliver continuous high flow (15 L/min) face-mask or nasal oxygen and a self-inflating positive pressure oxygen delivery system
  • High pressure suction (with suction catheters)
  • IV cannulae with infusion fluids and devices
  • A tipping trolley or bed
  • Pulse oximetry
  • Capnography
  • ECG machine (use recommended if high risk patients ASA Score 3 or higher).
  • Non-invasive automated blood pressure (NIBP) monitor with appropriate range of cuff sizes
  • An adequate range of sedation, analgesic, and resus drugs stored and checked in line with Trust policy
  • Stocks of reversal agents for benzodiazepines (flumazenil 500microgram in 5mL injection) and opioids (naloxone 400microgram in 1mL injection)
  • Dedicated recovery area with a trolley and monitoring as outlined above
  • Daily checks on equipment to be recorded in a logbook

4.6 Monitoring and procedural standards required

  • WHO checklist should be completed for all procedures
  • Use of supplementary oxygen is now recommended for ALL patients receiving moderate or deeper levels of sedation (unless previous Bleomycin exposure). This was previously only mandatory if using multiple drugs, opiates, and for high risk patients.
  • Continuous pulse Oximetry
  • Intermittent Non Invasive Blood Pressure monitoring (5 minutes intervals)
  • Continual monitoring of adequacy of ventilation with capnography is recommended for all moderately sedated patients (AABGI, AOMRC, RCOA). CO2 capnography should be available and used on all sedated patients, and continued into recovery. It provides an earlier warning of hypoventilation, apnoea, or airway obstruction, than using Oxygen saturation alone. Patients on supplementary oxygen may take several minutes to desaturate despite an obstructed airway.
  • Respiratory rate (generated by Capnography trace)
  • Sedation Scoring - Observers Assessment of Alertness/Sedation Scale (OAASS) (Appendix 5) or Ramsay Sedation Scale (Appendix 6)
  • Continuous ECG is now recommended for ALL patients moderately (or deeper) sedated (AOMRC, AAGBI). It was previously recommended for higher risk patients (ASA Score > 2 or cardiac Hx).
  • Secure venous access required.

Unless technically precluded e.g. uncooperative or combative patient, this monitoring must be recorded and documented by the dedicated trained observer on a standardised chart:

  • Baseline measurements before initiating sedation/analgesia
  • After administration of sedative-analgesic medications, and at regular intervals (usually 5 mins) during the procedure
  • Monitoring should continue into recovery, every 5 mins for 15 mins then every 10 mins until discharge criteria met. Note it is currently acceptable to record respiratory rate manually, without the use of capnography, in the recovery area (recognising not all recovery areas have capnography, although this is in development).
  • The record/chart may vary between facilities, but should be able to record all of the above information in a standardised clear format

The level of consciousness should be assessed by the patient’s ability to respond purposefully to verbal command or tactile stimulation. Verbal response also provides an indication that they are breathing. Patients whose only response is reflex withdrawal from painful stimuli are deeply sedated, approaching a state of general anaesthesia, and should be treated accordingly.

The ASA definition of “Deep” sedation correlates with a patient who does not respond to verbal or light stimuli, and may not be able to maintain a patent airway. There is a consensus that procedures requiring deep sedation require the practitioner to have the same level of training and skill as that required for a general anaesthetic.

4.7 Preventing Complications

Many of the complications associated with sedation and analgesia can be avoided if adverse drug responses are detected and treated in a timely manner i.e. before the development of cardiovascular decompensation or cerebral hypoxia. Deep sedation will be detected earlier if a standardized method of assessment of sedation level is used to monitor (and record) the level of consciousness during and after the procedure. See Modified OAASS score, and Ramsay Sedation Scale in Appendix.

The ASA explain that because sedation is a continuum, it is not always possible to predict how each individual patient will respond. Hence practitioners intending to administer a “moderate” level of sedation, should have the skills required to rescue a patient from an unintended deeper level of consciousness back to the intended sedation state. In particular, they require the skills to assess airway patency, and open an airway using simple techniques or supraglottic airway insertion (LMA/iGEL). They should be able to correct adverse physiologic consequences of deeper than intended sedation such as hypoventilation, hypoxia and hypotension, and return the patient to the intended sedation level using reversal agents if indicated. The use of checklists are recommended for the safe management of critical incidents (such as anaphylaxis), and these should be prominently displayed in clinical areas.

Contemporaneous recording of patient data is essential as it may disclose trends that could prove critical in determining the development or cause of adverse events. Manual recording (where monitored parameters are written on a chart) is preferred because it ensures that the individual caring for the patient is aware of changes in patient status in a timely fashion. If recording is performed automatically, device alarms must be set to alert the care team to critical changes in patient state.

The role of a “dedicated sedationist”

With increasingly complex procedures being performed, particularly on frail patients, or those with multiple co-morbidities, the use of a trained dedicated sedationist, whose sole responsibility is to administer sedation and monitor the patient, is becoming more common. The AOMRC states that if a dedicated sedationist is not used, then the operator-sedationist must be prepared to justify their practice. They require the presence of a third trained person for all but the simplest procedures (eg short dental cases), to ensure that one of the assistants can focus on safe sedation, and the other can assist the operator.

4.8 Post-procedure Discharge Criteria

  • Patients should be formally assessed for discharge suitability according to these criteria:
  • Baseline level of consciousness returned
  • Vital signs within normal limits
  • Respiratory status not compromised
  • Pain and discomfort have been addressed
  • Responsible adult supervision available for 24 hours
  • Verbal and written instructions given

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5. Safe use of Sedation Drugs

5.1 General Principles

  • Operators must be familiar with duration of action, dosage, adverse effects of all medicines that they use for conscious sedation.
  • The medicines and doses used to provide conscious sedation must carry a margin of safety wide enough to render loss of consciousness unlikely.
  • The dosages must be the minimum necessary to achieve sedation, titrated to individual patient’s clinical needs, taking into account age, weight, concurrent medication, clinical condition(s), and the procedure being undertaken. Older and frailer patients will almost always require smaller doses (and smaller boluses) than the norm.
  • The sedation practitioner should choose the appropriate drug depending on whether the patient requires anxiolysis, analgesia or both.
  • Single drugs are easier to titrate to effect. For non-painful procedures sedation with a single agent (usually midazolam) is sufficient. Painful procedures may require the addition of analgesia. (Benzodiazepines do not have analgesic action and therefore repeated dosing in attempt to control pain can result in overdose). If a local anaesthetic technique is not appropriate, systemic analgesia such as an opiate (e.g. fentanyl) is used in conjunction with midazolam.
  • Adequate time must be given to assess the effects of individual medicines before more is given. In the case of midazolam this will be 3-5 minutes, and with fentanyl within 1 minute.
  • Drugs in combination produce synergistic effects and safety margins are narrowed increasing the likelihood of over-sedation complications. Therefore, multiple drugs can only be administered for conscious sedation by a medical practitioner or against a prescription. The use of multiple drugs presents additional training requirements.
  • The practice of drawing up and administering whole ampoules without reference to dosage guidelines is not acceptable
  • Elderly patients are more sensitive to many drugs than younger patients. It is well established that the doses of midazolam and opioid they require is usually half or less than those required for younger patients. Subsequent incremental doses should also be reduced.

5.2 Specific Medicines used for Conscious Sedation

This section contains specific information on the use of midazolam, fentanyl, and flumazenil. For information of alternative agents, practitioners should always refer to an up-to-date copy of the British National Formulary and/or the manufacturers Summary of Product Characteristics.

Oral sedation is not recommended as titration to effect is not possible, and response unpredictable.

The use of propofol for sedation is not recommended by non-anaesthetists. This drug has the potential to cause rapid and profound changes in sedative/anaesthetic depth, has no specific antagonists and works synergistically with other sedative drugs. Therefore, its margin of safety is smaller in comparison to the drugs recommended below (5). For complex procedures requiring the use of propofol, an anaesthetist is required.

5.2.1 Benzodiazepines - Midazolam

The following dosage guidelines for midazolam should be followed in adults.
An intravenous injection of midazolam should be given slowly at a rate of
approximately 1 mg over 30 seconds.

In adults under 70 years.

  • Draw up not more than 5mg of midazolam prior to the procedure (undiluted 1mg/ml).
  • An initial titrated dose of 2 to 5mg should be given at least 3 minutes before starting the procedure with a sensible pause afterwards to observe effect.
  • The dose chosen will depend on the age and fitness of the patient. A 5mg dose will be more appropriate in a young fit adult.
  • Additional incremental boluses of up to 2mg may be given as necessary, appropriate for the duration of the procedure.

In adults over 70 years, and patients who are assessed to be frail, debilitated, chronically ill or high risk (ASA score>2)

  • Draw up not more than 5mg of midazolam prior to the procedure (undiluted 5ml ampoule).
  • The initial dose must be titrated up to a maximum of 2mg given at least three minutes before starting the procedure with a sensible pause afterwards to observe effect.
  • Further titrated doses of 1-2mg may be given as necessary. Since the peak effect may be reached less rapidly, additional midazolam should be titrated slowly and carefully.

5.2.2 Opioids - Fentanyl

Fentanyl should be given by slow intravenous injection over a period of 1 to 3 minutes.

  • Following an intravenous injection of fentanyl, the onset of action is almost immediate, however, the maximum analgesic and respiratory depressant effects may not be noted for several minutes. The usual duration of action is 30 to 60 minutes following a single intravenous dose.
  • When used in combination fentanyl should always be given before the benzodiazepine so that its effect can be observed before proceeding.
  • Draw up 100mcg in 2ml syringe (undiluted 50mcg/ml).
  • The usual initial dose in conscious sedation procedures is 50 micrograms with a reduced dose of 25 microgram to be used in the frail or elderly. Further boluses of 25-50mcg up to a total dose of 100mcg can be given as required. (occasionally bigger does may be required for procedures longer than 30 minutes, but extra doses must be titrated cautiously allowing time to observe peak effect).
  • 50microgram of fentanyl is equivalent in potency to 5mg of morphine or 37.5mg of pethidine.

5.3 Use of Reversal agents - Flumazenil and Naloxone

Patients who become hypoxemic or apnoeic during sedation/analgesia and/or after reversal should receive supplemental oxygen and positive pressure ventilation if spontaneous ventilation is inadequate after attempts to stimulate the patient. Performing a jaw thrust to open the airway is in itself stimulating and often stimulates spontaneous breathing.

  • Flumazenil and/or naloxone may be administered to improve spontaneous respiratory effort in patients who have received benzodiazepines or opioids. This may be especially helpful in cases where airway control and positive pressure ventilation are difficult.
  • Flumazenil is used for the reversal of the sedative effects of benzodiazepines e.g. midazolam. The usual dose is 200microgram injected over 15 seconds followed, at 60 second intervals, by additional doses of 100micrograms as required (typical dose 300-600microgram). The cause of sedation should be questioned if there is no response after repeated doses.
  • Naloxone is used to reverse opioid induced respiratory depression. The usual dose is 100-200microgram followed by additional 100microgram doses every two minutes if response inadequate.
  • If reversal is considered necessary in a patient who has received a mixture of midazolam and fentanyl, it is recommended that flumazenil is administered first. The only exception would a large dose of opioid has been injected.
  • After pharmacologic reversal, patients should be observed for at least 60 minutes to ensure that sedation and cardio respiratory depression does not recur once the effect of the antagonist dissipates. Because of the short elimination time of both flumazenil and naloxone, residual sedation can unexpectedly return. (Flumazenil half life 50 mins versus midazolam 5 hours.) Healthcare staff should be aware of the potential for re-sedation and take steps to minimise risks to patients. An example scenario is when patients are discharged home following short diagnostic and therapeutic procedures.
  • The routine reliance on flumazenil for reversal is not considered good practice and not without the potential for side effects. The use of sedation regimens that include routine reversal of sedative or analgesic agents is discouraged.
  • All cases where flumazenil is administered following conscious sedation should be recorded and units must monitor for excessive use of flumazenil by regular QA/audit or (where this is not feasible) by completing a Datix each time it is used. Overdose of midazolam, due to incorrect selection of a higher strength product (>1mg/mL), is a “Never Event.”

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Record: 2109
Clinical condition:

All procedures requiring Conscious Sedation. Common indications include gastrointestinal endoscopy, bronchoscopy.

Target patient group: All patients undergoing these procedures
Target professional group(s): Secondary Care Doctors
Secondary Care Nurses
Adapted from:

Evidence base

8. Evidence Base

1.Academy of Medical Royal Colleges and their Faculties. Implementing and ensuring Safe Sedation Practice for healthcare procedures in adults. 2003 (superceded by document 2013 (7))

2. National Patient Safety Agency. Rapid Response Report 11 -Reducing Risks of Overdose with Midazolam Injection. December 9th 2008. Accessed at

3. British Society of Gastroenterology. Guidelines on Safety and Sedation During Endoscopic Procedures. September 2003. Accessed at

4. Dell GD, Quine A. Cardio-pulmonary and Sedation-related Complications in Guidelines on Complications of Gastrointestinal Endoscopy. British Society of Gastroenterology November 2006 Accessed at

5. Guidance for the use of propofol sedation for adult patients undergoing ERCP and other complex upper GI endoscopic procedures, April 2011. Joint RCoA and BSG working party. Accessed 6th May 2013 at

6. Never Events List 2018. Accessed 15th January 2020 at

7. Academy of Medical Royal Colleges “Safe Sedation Practice for Healthcare Procedures Standards and Guidance” October 2013. Accessed 15th January 2020 at

8. Royal College of Anaesthetists “Chapter 7: Guidelines for the Provision of Anaesthesia Services in the Non-theatre Environment 2021” accessed 3rd August 2021 at:
9. Practice Guidelines for Moderate Procedural Sedation and Analgesia 2018. A report by the American Society of Anesthesiologists Task Force on Moderate Procedural Sedation and Analgesia. Anesthesiology 3 2018, Vol.128, 437-479

10. Safe Sedation of Adults in the Emergency Department, November 2012.
Accessed on 20th January 2020 at:

11. Association of Anaesthetists of Great Britain and Ireland. Recommendations for standards of monitoring during anaesthesia and recovery 2021. Accessed on 3rd August 2021 at:

12. Academy of Medical Royal Colleges Safe Sedation Practice An Update, February 2021. Accessed 3rd Auguist 2021at:

Approved By

Trust Clinical Guidelines Group

Document history

LHP version 2.1

Related information

9. Appendix

Appendix 1: American Society of Anesthesiologists (ASA) physical status grade

  1. Healthy patient. Localised surgical pathology with no systemic disturbance
  2. Mild to moderate systemic disturbance (the surgical pathology or other disease process) No activity limitation.
  3. Severe systemic disturbance from any cause. Some activity limitation
  4. Life-threatening systemic disorder. Severe activity limitation
  5. Moribund patient with little chance of survival.

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Appendix 2: The American Society of Anesthesiologists (ASA) uses the following definitions for sedation:

  1. Minimal Sedation (anxiolysis) is a drug induced state during which patients respond normally to verbal commands. Although cognitive function and coordination may be impaired, ventilatory and cardiovascular functions are unaffected.

  2. Moderate Sedation (“Conscious Sedation”) is a drug induced depression of consciousness during which the patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained.

  3. Deep Sedation/Analgesia is a drug induced depression of consciousness during which patients cannot easily be aroused but respond purposefully following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate. Cardiovascular function is usually maintained.

  4. General Anaesthesia is a drug induced loss of consciousness during which patients are not rousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired. Patients usually require assistance in maintaining a patent airway, and positive pressure ventilation may be required because of depressed spontaneous ventilation or drug induced depression of neuromuscular function. Cardiovascular function may be impaired.

Appendix 3: NAP5 suggestion for describing sedation definitions from a patient's perspective, as part of a process of consent


What will this feel like? 

What will I remember? 

What is the risk related to the sedation drugs? 

Not sedated; awake 

I am awake, possibly anxious. There may be some mild discomfort (depending on what I am having done) 


Zero: not applicable 

Minimal sedation 

I am awake and calm. There may be some mild or brief discomfort 

Probably everything 

Very low risk 

Moderate sedation 

I am sleepy and calm but remain in control. I may feel some mild discomfort 

I might remember some things 

Low risk 

Deep sedation 

I am asleep. I will not be in control 

Probably very little 

Higher risk. My breathing may stop when I am asleep—and I may need help to breathe—a tube might be inserted into my nose, mouth, or windpipe. I will need oxygen and special monitoring 


I am deeply ‘asleep’ and unable to respond 

Very unlikely to remember anything 

High risk (but the presence of an anaesthetist is designed to increase safety). My breathing may stop and my blood pressure and heart rate may decrease. I will need a specialist doctor to look after my breathing and support my blood pressure and heart rate. I will need oxygen and special monitoring and equipment 


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Appendix 4: Modified Observers Assessment of Alertness/Sedation Scale (OAASS)


Responds readily to name spoken in normal tone (alert)


Lethargic response to name spoken in normal tone


Responds only after name called loudly/repeatedly


Responds only after mild prodding/shaking


Responds only to deep stimulus (eg trapezius squeeze)


Does not respond to deep stimulus


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Appendix 5: Ramsay Sedation Scale


Anxious and agitated or restless or both


Cooperative, orientated and tranquil


Responding to commands only


Brisk response to light glabellar tap or loud auditory stimulus


Sluggish response to light glabellar tap or loud autidory stimulus


No response to stimulus


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Appendix 6: Continuum of depth of sedation. A summary of the team, skills, monitoring, environment and facilities. AOMRC Standards and Guidance 2013


Minimal Sedation/ Anxiolysis

Moderate Sedation/Analgesia (‘Conscious Sedation’)

Deep Sedation/ Analgesia


Normal response to verbal stimulation

Purposeful* response to verbal or tactile stimulation

Purposeful* response following repeated or painful stimulation



No intervention required

Intervention may be required

Spontaneous ventilation



May be inadequate

Cardiovascular function


Usually maintained

Usually maintained

N.B. Increasing depth of sedation is accompanied by increasing depression of physiological systems (CNS, RS, CVS). Sedation is a continuum and it is not always possible to predict how an individual patient will respond. Practitioners administering sedation, and those tasked with monitoring, must be trained to promptly recognise and manage patients whose level of sedation becomes deeper than intended and experience respiratory depression, loss of airway and inadequate ventilation

The team

  • Operator- sedationist
  • Appropriate second


  1. 1  Brief, simple procedures – a second individual may suffice to monitor the patient and assist the operator-sedationist with interruptible ancillary tasks of short duration5,12§
  2. 2  For all but brief and simple procedures a three person model is advocated:
    • Operator-sedationist
    • Trained assistant to monitor


  • Assistant to procedure
  1. 3  For complex or prolonged procedures or where patient frailty and significant co- morbidities exist, a dedicated sedationist is required
  • Operator
  • Dedicated sedation-

trained anaesthetist or alternatively an appropriately trained healthcare professional§§

  • Trained assistant



Dictated by co- morbidity

Verbal responsiveness. SaO2. NIBP. Use of ECG and ETCO2 are Developmental Standards and already recommended by one authority33–34

Response to repeated/painful stimulus, SaO2, ECG, NIBP, ETCO2

Availability of resuscitation skills

BLS – as defined by RC(UK)40

ILS – as defined by RC(UK)

ALS – as defined by RC(UK)

Specific airway skills required

Basic airway manoeuvres

Competency in the use of basic airway manoeuvres, airway adjuncts, supraglottic devices, and bag and mask ventilation

Environment and facilities

ASA 1 and 2 patients are suitable for treatment in primary and secondary care

Where anaesthetic drug techniques (with or without opioid) are
used, trained personnel must be immediately available to assist with the resuscitation of a collapsed patient so that the patient’s airway, breathing and circulation are supported fully without delay



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Equity and Diversity

The Leeds Teaching Hospitals NHS Trust is committed to ensuring that the way that we provide services and the way we recruit and treat staff reflects individual needs, promotes equality and does not discriminate unfairly against any particular individual or group.