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SAFETY AND SEDATION DURING ENDOSCOPIC PROCEDURES
SUMMARY OF RECOMMENDATIONS
1.
Safety and monitoring should be part of a quality assurance programme for
endoscopy units. (C)
2.
Resuscitation equipment and sedation reversing/antagonist drugs must be
available in the endoscopy room and recovery area. (C)
3.
Drugs and equipment necessary for the maintenance of airway, breathing
and circulation should be present in the endoscopy room and recovery area
and be checked regularly. (C)
4.
A qualified nurse trained in endoscopic techniques and rescusitatory
techniques should monitor the patient’s condition during procedures. (C)
5.
Staff of all grades and description should be familiar with resuscitation
methods and undergo periodic re-training. (C)
6.
Prior to endoscopy, risk factors should be identified in both out-patients
and in-patients. (C)
7.
Endoscopy is sometimes an emergency procedure, so high-risk patients
should be resuscitated as much as possible before attempting the
procedure. (C)
8.
a). Dosage of benzodiazepines and opiates should be kept to a minimum
to achieve sedation and should be within the manufacturers guidelines.
(C)
b) Opioids should, whenever possible, be given before benzodiazepines
and
their effect observed before proceeding. (B)
c) Most endoscopic practices recommend that 5 mg of Midazolam
should usually be the maximum dose given and that elderly patients are
given 1-2 mg initially with a sensible pause to observe effect. Doses in
excess of Pethidine 50mg or Fentanyl 100 mcg are seldom required and
elderly patients will require dose reduction (usually below 50%) when
these drugs are used. (C)
9.
All sedated patients must have a flexible (not “butterfly” ) intravenous
cannula in situ throughout the procedure and recovery period. (C)
10.
Oxygen should be given to all sedated patients and selected unsedated
patients throughout the procedure and recovery period.
(C)
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11.
The endoscopist is responsible for the health and safety of the patient
throughout the procedure and is not just a technician. (C)
12.
Pulse oximetry monitoring should be used in all sedated patients and ECG
and blood pressure monitoring should be readily available for high risk
patients. (C)
13.
Clinical monitoring must be continued into the recovery area. (C)
14.
Records of management outcome and adverse events should be taken as
part of the patient plan and kept and used for audit of departmental practice. (C)
Grading of Evidence
(A) Meta analysis,large randomised controlled trials
(B) Good evidence from trials,but less convincing e.g. smaller number in trials
(C) Specialist opinion
There has been considerable progress in sedation practice during endoscopic
procedures since the last guidelines were published over 10 years ago. Audits by
Daneshmend 1991(1), Quine 1995 (2) and Bowles 2001 (3) revealed that the culture
has changed substantially from that of the late 1980’s and early 90’s. However, there
is no room for complacency, and at the time of writing there is no evidence to suggest
that the 30 day mortality of 1:2000 reported by Quine (1995) has improved
significantly. This may be partly explained by the almost total lack of structured
training in safe sedation across the profession. A recent report has again highlighted
the problem (4) and suggested that each hospital nominate two Consultants, one
Anaesthetist and one a user of Sedation (usually a Gastroenterologist) to collaborate
in the local implementation of guidelines and the provision of a specialist service for
patients with particular problems.
The guidelines below have been mainly drawn from the Recommendations for
Standards of Sedation and Patient Monitoring during Gastrointestinal Endoscopy,
published by the Endoscopy Section Committee Working Party . The report of the
Working Party on guidelines for Sedation by Non-anaesthetists, published by The
Royal College of Surgeons of England, June 1993, and Implementing and ensuring
safe sedation practice for healthcare procedures in adults, the report of an
intercollegiate working party chaired by the Royal College of Anaesthetists 2002 (4).
Where possible the original wording of the documents has been retained and the
documents updated
Although some endoscopic procedures such as routine diagnostic upper GI endoscopy
can be carried out without sedation, many other endoscopic procedures are unpleasant
and sedation as an adjunct to good pain relief and sympathetic patient management
can improve both patient tolerance and acceptance and increase the technical success
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of the procedure. The fact that the procedure can be performed without systemic
medication increases the pressure to use sedation safely. Endoscopists should
recognise that any drug which depresses the central nervous system has the potential
to impair respiration, circulation or both.
Conscious sedation has been defined as “a technique in which the use of drug or
drugs produces a state of depression of the central nervous system enabling
treatment to be carried out, but during which verbal contact with the patient is
maintained throughout the period of sedation. The drug and techniques used to
provide conscious sedation should carry a margin of safety wide enough to
render loss of consciousness unlikely”. If verbal responsiveness is lost the patient
requires a level of care identical to that needed for general anaesthesia.
Sedatives and anxiolytics such as Benzodiazepines have no analgesic properties when
conventional doses are given systemically, and attempts to use them to control pain
will result in significant overdose. Pain control requires the administration of specific
analgesic agents. The most popular of these agents are Fentanyl and Pethidine and
should whenever possible, be given before the Benzodiazepine, and their effect
observed before the administration of the Benzodiazepine. Safety will only be
optimised if practitioners use defined methods of sedation for which they have
received formal training.
The Endoscopists Role

Only trained and competent endoscopists should assume the responsibility
both for sedating the patient and carrying out the examination.

Trainees must be adequately instructed in IV sedation techniques and closely
supervised until competent

The patient’s clinical condition should be observed by a dedicated registered
nurse and by the endoscopist.

Drugs and equipment necessary for resuscitation are the responsibility of the
consultant endoscopists and the nurse in charge of the unit and should be
available immediately when required. Checking procedures should be carried
out prior to each endoscopy list.

Equipment available in the Endoscopy room and recovery area (if separate)
should include the basic drugs and equipment necessary for the maintenance
of airway, breathing and circulation as well as a source of oxygen, suction and
a tipping trolley.

Staff of all grades and disciplines should be familiar with resuscitation
methods and undergo periodic retraining. Regular practice in simulated
emergencies is recommended.
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The Role of the Endoscopy Assistants
A minimum of two endoscopy assistants, of whom at least one is a qualified nurse,
must be present at each endoscopy. The assistant dedicated to patient care has a key
role in monitoring the patient’s safety, comfort and well-being and in communicating
significant changes to endoscopists.
All endoscopy assistants must be capable of helping the endoscopists in the case of
emergency such as cardiac or respiratory arrest, and adequate training and periodic
retraining should be made available. It is the responsibility of the nurse in charge of
the area and the endoscopists to make sure that all equipment for resuscitation is
immediately available and regularly checked. Checking procedures should be carried
out prior to each endoscopy list.
At Risk Patients
Many endoscopies are carried out on elderly patients who may have significant comorbidity and even in younger patients, the presence of heart disease, cerebrovascular
disease, lung disease, liver failure, anaemia, shock and morbid obesity may indicate
dangerous risk factors. Current medication needs to be determined and evaluated as
to its possible effects on the sedation process.
A pre-endoscopy patient record compiled by the dedicated nurse is especially helpful
in identifying risk factors pertinent to the endoscopy.
Sedation Techniques
The majority of endoscopies are carried out using some form of sedation, usually with
a benzodiazepine. There is still no tradition of formalised training in sedation in the
United Kingdom. The exact doses needed to achieve safe sedation with
benzodiazepine are variable, but it is both sensible and safer to use the minimum
amount of drugs within the manufacturers’ guidelines to ensure patient comfort and
the success of the endoscopy. Elderly patients and patients with significant comorbidity such as cardiac or renal failure will require smaller doses as the drugs take
effect more slowly, and there is a longer recovery period.
Other Sedative Drugs
Drugs such as Propofol, Ketamine and analogous compounds require specialist
knowledge, skills and equipment and should never be used without the presence of
a trained anaesthetist. Certainly these drugs cannot at the present level of knowledge
be considered safe for use by the operator sedationist (5)
Entonox
Entonox is a 50/50 mixture of nitrous oxide and oxygen with good analgesic but little
hypnotic effect. It is best stored at room temperature and given by mask or
mouthpiece via a demand valve. Careful instruction is important to ensure
compliance but compliance, and therefore inhalation, ceases as sedation approaches
making it a safe analgesic in the majority of patients. It is not safe for use in patients
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who have compromised respiratory function or pneumothorax. It is perhaps best used
for moderately painful procedures such as colonoscopy or flexible sigmoidoscopy and
recovery is rapid with a “washout time” of five to ten minutes.
Difficult Patients
Patients occasionally become restless or even violent following sedation. This
situation can sometimes be salvaged by reversing the sedation which may allow the
endoscopy to proceed but when such difficulty can be anticipated general anaesthesia
is usually the best option.
Alcoholics and regular benzodiazepine users are notoriously difficult to sedate and
their response may be unpredictable or even paradoxical on occasions. In these
circumstances the prior administration of an opioid can be useful.
Children
These guidelines are intended for adult endoscopy only. The Endoscopy Working
Party of the Paediatric Section of the B.S.G. are currently reviewing the guidelines for
safe sedation in children and these will be published in due course
Special Circumstances
In Colonoscopy and ERCP Benzodiazepine sedation is usually supplemented with
opioids such as pethidine and Fentanyl. The dose requirement is sometimes
predictable, but synergism between these drugs may lead to an increase in cardiorespiratory events. If the use of an opioid is anticipated (for example, by a previous
difficult procedure) then it should be given first and the benzodiazepine dose titrated
carefully with an up to four-fold decrease in total. (7) Specific antagonists for
benzodiazepines and opioids should be available at all times in the endoscopy unit
and recovery area but their presence should not encourage over dosage of the sedative
drugs. Administration of an antagonist does not alter the requirement to monitor vital
functions where depression of these has occurred. Flumazenil may take several
minutes to completely reverse benzodiazepine respiratory depression. The duration of
action of both opiods and benzodiazepines is longer than that of their antagonist and
reversal may be short-lived, needing repeat administration.
It is essential that all patients undergoing intravenous sedation have a cannula placed
in the vein for reliable, continuous venous access during the procedure. A flexible
plastic cannula with an introduction needle that is removed after insertion must
be employed. This cannula must be left in place until recovery is complete.
Clinical Monitoring, pre-oxgenation and supplemental oxygen
Oxygen desaturation can occur during endoscopic procedures where sedation is used,
especially when the patient has been over sedated remembering that a reading
below 90% is dangerous and requires immediate intervention. The Endoscopists
is responsible for the well being and clinical observation of the patient undergoing
endoscopy in conjunction with another individual. This individual should be a
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qualified nurse trained in endoscopic techniques or another medically qualified
practitioner.
Preoxygenation with oxygen enriched air (2 litres per minute ) is safe even in chronic
obstructive pulmonary disease and greatly diminishes or prevents hypoxaemia. This
should be used routinely in all at-risk patients.
Pulse oximetry should always be used during endoscopy, as clinical observation is a
poor method of determining respiratory depression and hypoxia. Alarm systems may
alert the endoscopist in the event of deterioration in the patient’s clinical condition but
there is no evidence that the routine use of monitoring equipment will reduce the
morbidity and mortality associated with Endoscopy. However the following
recommendations should ensure high quality patient care and reduce the risk of
cardio-pulmonary events:



The use of monitoring devices and alarms should not distract the endoscopists
and assistant from basic clinical observations
Pulse oximetry should be combined with continuous ECG monitoring in those
patients who are at high cardiac risk.
In the event of desaturation, encouraging the patient to breathe deeply with
supplemental oxygen, termination of the procedure, assisted ventilation and
pharmacological reversal of either the benzodiazepine and/or the opioid may
remedy this.
Patient Recovery
Clinical monitoring must be continued into the recovery period and supplemental
oxygen and pulse oximetry may be needed and it is worth remembering that
respiratory complications such as aspiration pneumonia may present many hours or
even days after the endoscopy.
The endoscopists is still responsible for the post endoscopy recovery period and
should give clear instructions to the recovery nursing staff or ward, especially when
an adverse event has occurred.
Day cases should be accompanied home by a responsible adult who should then stay
with them for at least 12 hours if they live alone. Clear written instructions should be
given to this person as to what to do and whom to contact in event of problems
arising. It is recommended that patients who have been sedated with an intravenous
benzodiazepine do not drive a car, operate machinery, sign legal documents or drink
alcohol for 24 hours. This irrespective of whether their sedation has been reversed
with flumazenil.
Records and Audit
The endoscopic records should include a patient-specific record of the procedure
(paper or electronic, or preferably both). This will include the pre-endoscopic state of
the patient, the drugs used during the procedure and any adverse events encountered.
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Audit should be an integral part of the records of every endoscopy department.
Appropriate use of this technique is essential in evaluating the frequency of adverse
events related to both the procedure and to the sedation employed.
References
1. Daneshmend TK, Bell G D, Logan R F A , Sedation for Upper Gastrointestinal
Endoscopy: results of a national survey, GUT 1991; 32: 12-15
2. Quine M A, Bell G D, McCloy R F, Charlton J E, Devlin H B, Hopkins A A.
Prospective audit of upper Gastrointestinal Endoscopy in two regions of England:
Safety, staffing and sedation methods. Gut 1995;36:462-467.
3. Bowles C J A, Leicester R, Swarbrick E, Williams C B, Romaya C, Epstein O,
GUT 2001; 48 (Supplement 1): A21
4. Implementing and ensuring Safe Sedation Practice for Healthcare Procedures in
adults. Report of a Working Party established by the Royal College of
Anaesthetists, www.aomrc.org.uk November 2001
5. Bell G D, Charlton J E, Editorial – Colonoscopy – is Sedation necessary and if so
does IV Propafol have a role? Endoscopy 2000;32:264-267
6. Ben Shlomo I, Adb-el-Khalim H, Ezry J, Zohar S, Tverskoy M, Midazolam acts
synergistically with Fentanyl for induction of anaesthesia, British Journal of
Anaesthesia 1990:64:45-7
Acknowledgements
Mrs Diane Campbell and Professor Duncan Bell kindly gave of their time to review
this manuscript.
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This paragraph should be on the inside front cover.
This report was originally published in 1991 and has been updated by Dr Robin
Teague on behalf of the Endoscopy Section Committee of the British Society of
Gastroenterology.