Management of Entonox

Version / 6
Name of responsible (ratifying) committee / Formulary and Medicines Group
Date ratified / 19th September 2014
Document Manager (job title) / Libby Burton Smith Acute Pain Sister
Date issued / 10th October 2014
Review date / 09th October 2016
Electronic location / Clinical Policies
Related Procedural Documents / See section 8
Key Words (to aid with searching) / Entonox; analgesia; procedural pain; rapid onset/offset

Version Tracking

Version / Date Ratified / Brief Summary of Changes / Author
6 / 19/09/2014 / Nil change to clinical content
New Trust template / Libby Burton Smith

CONTENTS

QUICK REFERENCE GUIDE 3

1. INTRODUCTION 4

2. PURPOSE 4

3. SCOPE 4

4. DEFINITIONS 4

5. DUTIES AND RESPONSIBILITIES 4

6. PROCESS 4

7. TRAINING REQUIREMENTS 6

8. REFERENCES AND ASSOCIATED DOCUMENTATION 6

9. EQUALITY IMPACT STATEMENT 7

10. MONITORING COMPLIANCE WITH PROCEDURAL DOCUMENTS 8

MONITORING 10

Specific Paediatric Preparation: 13

During the Procedure 13

Following the Procedure 14

QUICK REFERENCE GUIDE

Entonox is a ready-to-use medical gas mixture consisting of 50% nitrous oxide and 50% oxygen.

It is a safe and effective analgesic for all situations where rapid onset and offset is sought.

It provides pain relief and conscious sedation in midwifery and for a variety of short term procedures.

Departments carrying out procedures using entonox should be aware of and follow this policy.

All staff involved in administering entonox should have undergone formal training in its use and handling and be able to recognize and manage any complications.

1. INTRODUCTION

Many procedures or interventions are painful to the patient and the level of discomfort experienced is often underestimated or discounted as being part of a therapeutic or beneficial intervention.

Entonox is an inhaled agent that provides effective analgesia that can be self-administered to provide immediate pain relief. It is particularly suited for the relief of acute pain as a result of, for example, injury, trauma, therapeutic investigative procedures and maternity. Entonox was introduced commercially in 1965 and, following acceptance by the Central Midwives Board, became the normal method of pain control in childbirth utilised by the midwifery staff. Soon, Entonox was being used to control pain for accidents and emergencies and, by the early 1970s, was standard issue in most ambulances.

2. PURPOSE

This policy is to guide staff in the use of Entonox. It is not designed to restrict or limit professional judgment and decision-making

3. SCOPE

This policy applies to all permanent, locum, agency and bank of Portsmouth Hospitals NHS Trust, the MDHU (Portsmouth) and Carillion, whilst acknowledging that for staff other than those directly employed by the Trust the appropriate line management or chain of command will be taken into account.

4. DEFINITIONS

Entonox is a homogeneous gas mixture containing 50% nitrous oxide (N2O) and 50% oxygen (O2). It is stored in cylinders at 137 bar. This pressurised mixture remains gaseous at temperatures above –6oC.

Nitrous oxide is a colourless, sweet smelling gas with powerful analgesic properties. Pulmonary transfer of nitrous oxide is rapid, with onset of effect in seconds and full analgesia within one to two minutes. Likewise it is rapidly eliminated from the blood, via the lungs, when inhalation ceases.

Entonox combines the analgesic effect of the nitrous oxide with the anti-hypoxic effect of 50% oxygen.

5. DUTIES AND RESPONSIBILITIES

Anaesthetists: when an anaesthetist is involved in a patient’s care, it is his/her responsibility (not that of a surgeon) to seek consent for anaesthesia, having discussed the benefits and risks.

Midwives: in the maternity setting it is the midwife’s responsibility to establish the use of Entonox in childbirth, where its use is covered by NICE guidance ‘Care of women and their babies during labour’ Clinical Guideline 55.

Supervisors of clinical practice: will be responsible for auditing compliance with the BOC management guidelines on an ongoing basis

6. PROCESS

6.1 Storage

Where cylinders are brought into the building directly from outside storage during periods of low external temperature, to ensure gases are properly mixed, cylinders should first be either

a. Stored horizontally for 24 hours at a temperature above 10oC, or

b. Stored for at least 2 hours at a temperature above 10oC, then completely inverted three times, or

c. Placed in warm water at body temperature for 5 minutes, then completely inverted three times.

6.2 Prescribing and administration

Entonox must be prescribed by medical staff or non-medical prescribers with responsibility for the care of the patient prior to use and should only be administered by staff who are trained in both its use and the equipment available for its administration.

Entonox is self-administered using a dedicated Entonox demand valve

6.3 Indications

Entonox is indicated for the relief of acute moderate to severe pain of any aetiology (see contraindications at section 6.3 for exclusion criteria). The pain or discomfort could be: as the result of injury; due to a procedure carried out in hospital; or that incurred by women in childbirth and labour. For example:

· Fracture manipulation

· Endoscopy (e.g. colonoscopy)

· Suturing of lacerations

· Venopuncture

· Ophthalmic surgery

· Vascular procedures

· Radiological procedures

· Dermatological procedures

· Wound dressing changes

· Burns dressing

· Orthopaedic joint manipulation

· Patient mobilisation

· Childbirth

· Perineal suturing

· Wound drain removal

· Examination of wounds or fractures

6.3 Contraindications

Contra indication / Rationale
Pneumothorax, / The nitrous oxide constituent of Entonox passes into all gas-containing spaces in the body faster than nitrogen passes out. This can cause expansion of the gas space, compressing surrounding structures.
Bowel obstruction
Air embolism
Decompression sickness or following a recent underwater dive
Following air encephalography
Severe bullous emphysema
During myringoplasty
Head injuries with impaired consciousness. / Entonox will cause sedation, which may confound neurological observation of the patient.
Drug or alcohol Intoxication / Drowsiness and aspiration would be a hazard in the event of vomiting.
Maxillo-facial injuries / The patient may not be able to hold the mask tightly to the face or use the mouthpiece adequately.
Heavily sedated patients / The patient may be unable to use the equipment properly and increased sedation may be hazardous.

See Appendix 1 for protocols for practice. Critical Incident reporting within the Anaesthetic Department and completion of Trust risk forms will be the systems used to manage risk.

Record keeping, in high use departments an audit will be expected to be completed yearly to ensure that patients requiring entonox have documentation/prescription.

Adverse incident reporting where policy has not been followed, 100% of all incidents reported to risk management are discussed at mortality and morbidity meetings.

7. TRAINING REQUIREMENTS

Aim

To provide adequate information and knowledge to ensure the safe delivery of Entonox therapy to patients with acute pain.

Objectives

Staff will be able to:

· Define the indications for Entonox

· Describe Entonox and its effects

· List the contraindications/cautions in the use of Entonox

· Demonstrate an understanding of how the associated equipment operates

Workshop

Staff should be prepared by attending an Entonox workshop. An appropriately trained individual, who has the required knowledge and skill, should deliver this to ensure the appropriate information is offered effectively and safely. Within the workshop, staff should be given the opportunity to view the Entonox training videos available from BOC.

Otherwise, sufficient training may be obtained by completing the on-line training package provided by BOC at http://discover.entonox.co.uk/

A record should be kept of all those taught/updated.

Some staff will have received update/training as part of their preparation for registration. This should be credited to them on the record/ register. Midwives assume competency to prescribe and administer Entonox as part of their training.

8. REFERENCES AND ASSOCIATED DOCUMENTATION

· Royal Marsden Manual of Clinical Nursing Procedures. J Mallet and L Dougherty, 8th Edition 2011

· BOC Educational on-line material: http://discover.entonox.co.uk www.entonox.co.uk

· Entonox Medical Gas Data Sheet: HLC/401840/JIG/APUK/0410/3M

· Entonox:; everything a parent-to-be needs to know: HLC/402620/JIG/APUK/0609/3M

· Entonox; the natural choice for rapid and controlled pain relief during childbirth: HLC/402610/JIG/APUK/0609/3M

· Entonox; conquering procedural pain in children: HLC/402615/JIG/APUK/0609/3M

· Entonox; conquering procedural pain: HLC/402605/ JIG/APUK/0609/3M

· Entonox; controlled pain relief reference guide: HLC/401955/JIG/APUK/0409/2M

EQUALITY IMPACT STATEMENT

Portsmouth Hospitals NHS Trust is committed to ensuring that, as far as is reasonably practicable, the way we provide services to the public and the way we treat our staff reflects their individual needs and does not discriminate against individuals or groups on any grounds.

This policy has been assessed accordingly

Our valuesare the core of what Portsmouth Hospitals NHS Trust is and what we cherish. They are beliefs that manifest in the behaviours our employees display in the workplace.

Our Values were developed after listening to our staff. They bring the Trust closer to its vision to be the best hospital, providing the best care by the best people and ensure that our patients are at the centre of all we do.

We are committed to promoting a culture founded on these values which form the ‘heart’ of our Trust:

Respect and dignity

Quality of care

Working together

No waste

This policy should be read and implemented with the Trust Values in mind at all times.

Entonoxf Policy : Issue Number 6 Issue Date 10/10/2014 (Review date: 09/10/2016 (unless requirements change)

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Entonoxf Policy : Issue Number 6 Issue Date 10/10/2014 (Review date: 09/10/2016 (unless requirements change)

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10. MONITORING COMPLIANCE WITH PROCEDURAL DOCUMENTS

The compliance with his policy will be the responsibility of an Acute Pain Sister.

Monitoring of compliance will be the responsibility of the Acute Pain Service in conjunction with BOC Medical

In the event of a major epidemic or major incident, compliance with this policy may be difficult and will require a risk assessment of the ability to provide safe administration of entonox for procedures or analgesia.

Minimum requirement to be monitored / Lead / Tool / Frequency of Report of Compliance / Reporting arrangements / Lead(s) for acting on Recommendations
Yearly audit of training and equipment by Acute Pain Service, reviewed by BOC / Libby
Burton Smith / Acute Pain database / Annual / Policy audit report to:
· Acute Pain Service / Libby Burton Smith
BOCMedical representative
Risk management via departmental Mortality & Morbidity meeting / Libby Burton Smith / Adverse incident report / Monthly / Policy audit report to:
· Acute Pain Service / Libby Burton Smith

Entonoxf Policy : Issue Number 6 Issue Date 10/10/2014 (Review date: 09/10/2016 (unless requirements change)

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APPENDIX 1: EVIDENCE BASED PROTOCOL FOR PRACTICE

INITIAL ASSESSMENT /

RATIONALE

Assess the degree of pain likely for the procedure being performed / To determine whether Entonox is required
Ensure that Entonox is not contra-indicated for the patient / To reduce the likelihood of complications
Assess individual patient for the ability to use Entonox. The patient should be able to:
· Understand simple instructions (via an interpreter if necessary)
· Hold the demand valve and inhale the gas through the mask or mouthpiece while breathing normally. / To ensure the patient is able to use Entonox effectively
If Entonox is considered inappropriate for either the patient or the procedure, alternative analgesia should be prescribed.

PREPARATION

Ensure the Entonox has been prescribed on patients drug chart / Not required in Maternity
If Entonox is to be administered more frequently than every four days or for more than 6-12 hours, routine blood cell counts should be performed / To observe for :
· evidence of megaloblastic change in red cells
· reduced production of leucocytes
The area should be well ventilated to prevent the accumulation of nitrous oxide / To maintain a safe environment. The occupational exposure standard for long term exposure is 100 parts per million (ppm)
Staff should be trained in the use and applications of Entonox / To allow staff to be aware of the side effects and occupational exposure limits of Entonox
Gather and prepare the following equipment:
1. Turn Entonox cylinder on and prime the administration set by pressing the test button on the back of the demand valve.
2. Check the cylinder to ensure it is at least a quarter full. If it is not, ring the porter to change the cylinder.
3. Attach the filter to mask or mouthpiece before attaching this to the demand valve / To ensure immediate availability of Entonox once inhalation commences
To reduce risk of infection
Entonox cylinders should be checked carefully before use to ensure they contain the correct mix of 50% nitrous oxide and 50% oxygen
Ensure that a saturation monitor is available if the patient has respiratory or cardiac problems / To prevent drug errors as stronger concentrations of nitrous oxide are available in the hospital in similar cylinders
To prevent using a cylinder that is at temperatures lower than -6oC and has not been left to homogenise at 10oC
To prepare the patient:
· Explain the procedure to be carried out and how Entonox will be used, including information about the side effects
· Reassure them that if side-effects occur they wear off quickly once they stop inhaling the gas / To relieve anxiety and determine level of co-operation
The patient should not eat anything for an hour before procedure. Not applicable to pregnant women in maternity. / To reduce the likelihood of nausea and vomiting.
To prepare the patient: continued
Give supplementary analgesia as prescribed:
· Oral or rectal drugs should be given some time before starting the procedure, to allow full effect.
· The patient may continue to use their PCA if one is in progress
· A bolus of intravenous opiate may be given if a high degree of pain is anticipated / To provide additional pain relief
The patient should be allowed to practice using the Entonox before the procedure is started / To ensure an effective technique is established
If the patient is unable to maintain an effective seal or inhale the gas effectively the use of Entonox should be abandoned and alternative analgesia and/or sedation should be prescribed

ADMINISTRATION

To administer the Entonox: