Earlobe Capillary Blood Gas Sampling in Adults Clinical Guideline V1.0 Page 1 of 12 Earlobe Capillary Blood Gas Sampling in Adults Clinical Guideline V1.0 June 2018
Earlobe Capillary Blood Gas Sampling in Adults Clinical Guideline V1.0
Page 1 of 12
Earlobe
Capillary Blood Gas Sampling in Adults
Clinical Guideline
V1.0
June 2018
Earlobe Capillary Blood Gas Sampling in Adults Clinical Guideline V1.0
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1. Aim/Purpose of this Guideline
Arterialised capillary blood samples obtained from the earlobe of stable adult patients may be used to measure a number of variables that are required to safely monitor patients undergoing treatment with Non-Invasive Ventilation (NIV). In the assessment of blood gas tensions, capillary blood specimens have been shown in the literature to be comparable to arterial blood specimens with the added benefits of improved patient satisfaction and decreased risk of complications.
1.1. This guidance applies to all healthcare professionals performing this procedure. Those undertaking the procedure should ensure that it is appropriate for each patient and that they have achieved an adequate level of competency. It is the responsibility of the person performing the procedure to document the results in the medical notes and refer to medical staff if required.
1.2. Competency in this procedure is assessed through the ‘Earlobe Capillary Blood Gas Sampling - Supervised Practice Workbook’. Completion of the associated eLearning package and ten supervised procedures are required prior to final competency sign off.
2. The Guideline
2.1. Arterial Blood Gas (ABG) sampling provides essential information for the management of patients with a wide range of conditions. In particular, those patients requiring NIV require serial monitoring with several samples over days1,2. This is known to cause discomfort to patients3 and carries a small risk of complications such as haematoma formation or vessel injury.
2.1.1. Capillary Blood Gas (CBG) samples taken from an earlobe that has been ‘arterialised’ by use of a rubefacient cream represent a significantly less painful experience for patients and provide comparable results to ABGs in stable patients4.
2.1.2. Variations in technique can introduce significant differences in results thereby making a standardised procedure essential for all staff5.
2.2. Indications:
There are a number of indications for CBG sampling in in-patients. These include:
Monitoring of patients receiving NIV2 in line with trust policy: ‘The Use of Non-Invasive Ventilation in Patients with Acute Type 2 Respiratory failure; V1.0; May 2014.’
In the assessment of respiratory function in haemodynamically stable patients4.
Assessment of supplementary oxygen requirements7.
2.3. Contraindications:
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Haemodynamically unstable/shocked patients.
Abnormal puncture site – e.g. inflamed, localised infection or oedematous earlobe.
Previous reaction to Transvasin cream or chlorhexidine swabs.
Arterial access available (e.g. radial arterial line)
2.4. Equipment:
Clean tray with sharps box
Clean gloves and other Personal Protective Equipment (PPE)
Transvasin cream
2% chlorhexidine swab
Size 11 retractable scalpel
Heparinised capillary tube with mixing wire and end caps
Sterile gauze
Appropriate dressing (e.g. plaster)
2.5. Procedure:
Identify the patient in accordance with the ‘Positive Patient Identification Policy’. Explain the procedure to the patient and obtain informed verbal consent in accordance with the ‘Consent Policy’.
Wash hands and don appropriate PPE. Minimum requirements are clean gloves and apron.
Apply ‘Transvasin’ cream to the earlobe. Leave for a few minutes whilst preparing other equipment – the earlobe should become warm and erythematous.
Insert the mixing wire into the capillary tube and attach an end cap to one end
Remove the cream and disinfect the earlobe using a chlorhexidine swab. Allow to dry.
Use a size 11 scalpel blade to make an incision to a depth of 3mm, parallel to and in the middle of the edge of the earlobe.
Wipe away the first droplet of blood to ensure sample accuracy.
Allow a second, large droplet of blood to form.
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Place the end of the capillary tube into the droplet of blood and allow to fill, avoiding introducing air bubbles into the sample. Do not squeeze the earlobe.
Once full, apply the end cap to the capillary tube.
Apply firm pressure to the wound until bleeding has stopped, apply dressing.
Run the magnet the length of the capillary tube 10 times to ensure thorough mixing.
Attach a patient identification label to the tube at the patient’s bedside and note the inspired oxygen concentration (FiO2).
Immediately analyse the sample, in accordance with Point of Care Testing Policy.
Document result and FiO2 in medical notes. Refer results to medical team immediately.
2.6. Interpreting Results:
When using a standardised technique, arterialised CBG results closely correlate to ABG results and have similar normal ranges. An exception is for values for paO2 greater than 20kPa where significant variation is encountered4. For these patients the FiO2 should be reduced and the test repeated. The adjusted reference ranges4 are shown in Table 1.
Table 1. Current Trust ABG ranges with adjusted CBG ranges. Calculated using method described by Richter et al4.
Value ABG range Adjusted CBG Range
pH 7.350-7.450 7.342-7.442
paO2 (kPa)
for values <20kPa
12.0-15.0 12.03-14.97
paCO2 (kPa) 4.50-6.40 4.59-6.45
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2.7. Audit Tool
To be undertaken annually, with results reported at Respiratory Weekly Meeting.
Criteria Expected Compliance
Staff undertaking procedure to have completed competency sign off or be directly supervised
100%
Result documented in medical notes 100%
FiO2 documented 100%
Documentation that result has been referred immediately to medical team
100%
3. Monitoring compliance and effectiveness
Element to be monitored
Adherence to full guideline
Lead Ward Managers/Lead Consultant
Tool Adult Tool in Section 2.7.
Frequency Annual
Reporting arrangements
Respiratory weekly meeting
Acting on recommendations and Lead(s)
Where changes required, a lead person will be identified, reporting to the respiratory meeting
Change in practice and lessons to be shared
Required changes to practice will be identified and actioned within 3 months. A lead member of the team will be identified to take each change forward. These will be presented at the weekly respiratory meeting where required.
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4. Equality and Diversity
4.1. This document complies with the Royal Cornwall Hospitals NHS Trust service Equality and Diversity statement which can be found in the 'Equality, Diversity & Human Rights Policy' or the Equality and Diversity website.
4.2. Equality Impact Assessment
The Initial Equality Impact Assessment Screening Form is at Appendix 2.
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Appendix 1. Governance Information
Document Title Earlobe Capillary Blood Gas Sampling in Adults Clinical Guideline V1.0
Date Issued/Approved: 1 June 2018
Date Valid From: 1 June 2018
Date Valid To: 1 June 2021
Directorate / Department responsible (author/owner):
Respiratory Directorate Dr Alexander Lomas Dr James Pickering
Contact details: [email protected]
Brief summary of contents Procedural guidance on sampling and processing of earlobe capillary blood specimens in adult patients
Suggested Keywords: Capillary blood gas, non-invasive ventilation, CBG, NIV
Target Audience
RCHT PCH CFT KCCG
Executive Director responsible for Policy:
Medical Director
Date revised: New document
This document replaces (exact title of previous version):
New document
Approval route (names of committees)/consultation:
Respiratory Governance Meeting,
Cardio-respiratory Directorate,
Divisional Business and Governance
Divisional Manager confirming approval processes
Divisional Manager, Medicine/ED
Name and Post Title of additional signatories
Not Required
Name and Signature of {Original Copy Signed}
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Divisional/Directorate Governance Lead confirming approval by specialty and divisional management meetings
Name:
Signature of Executive Director giving approval
{Original Copy Signed}
Publication Location (refer to Policy on Policies – Approvals and Ratification):
Internet & Intranet Intranet Only
Document Library Folder/Sub Folder Clinical / Respiratory
Links to key external standards
https://www.brit-thoracic.org.uk/standards-of-care/guidelines/bts-guideline-for-emergency-oxygen-use-in-adult-patients/
https://www.brit-thoracic.org.uk/standards-of-care/guidelines/btsics-guidelines-for-the-ventilatory-management-of-acute-hypercapnic-respiratory-failure-in-adults/
Related Documents:
1. Guideline for emergency oxygen use in adult patients. British Thoracic Society. Emergency Oxygen Guideline Group. Thorax 2008; 63 (Suppl VI):vi1–vi68. doi:10.1136/thx.2008.102947
2. BTS/ICS Guidelines for the Ventilatory Management of Acute Hypercapnic Respiratory Failure in Adults. British Thoracic Society/Intensive Care Society Acute Hypercapnic Respiratory Failure Guideline Development Group. Davidson AC, et al. Thorax 2016; 71:ii1–ii35. doi:10.1136/thoraxjnl-2015-208209
3. An audit of the patient's experience of arterial blood gas testing. Crawford A. Br J Nurs. 2004 May 13-26; 13 (9):529-32.
4. Capillary blood gas as a substitute for arterial blood gas: a meta-analysis. Richter et al. British Journal of Hospital Medicine, March 2014, Vol 75, No 3.
5. Vaquer et al.: Earlobe arterialized capillary blood gas analysis in the intensive care unit: a pilot study. Annals of Intensive Care 2014 4:11.
6. Sampling Techniques – Collecting a capillary sample from an adult or a child three months of age or older. Radiometer 2012. Available at http://www.avoidpreanalyticalerrors.com/
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files/Sampling_tech_collect_capillary_adult_
child_3_months_older.pdf (accessed 03/02/2017)
7. Capillary blood gas analysis for long term oxygen therapy assessment. Ridley et al. Clinical Medicine 2001. Vol 1 No 4:326.
Training Need Identified? Yes
Version Control Table
Date Version No
Summary of Changes Changes Made by
(Name and Job Title)
8 Nov 17 V1.0 Initial Issue Dr Alexander Lomas ACCS CT1
All or part of this document can be released under the Freedom of Information Act 2000
This document is to be retained for 10 years from the date of expiry.
This document is only valid on the day of printing
Controlled Document
This document has been created following the Royal Cornwall Hospitals NHS Trust Policy on Document Production. It should not be altered in any way without the express
permission of the author or their Line Manager.
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Appendix 2. Initial Equality Impact Assessment Form
Name of the strategy / policy /proposal / service function to be assessed:
Earlobe Capillary Blood Gas Sampling in Adults Clinical Guideline V1.0.
Directorate and service area: Respiratory Directorate/ Medicine Inpatient Wards
Is this a new or existing Policy? New
Name of individual completing assessment: Dr Alexander Lomas
Telephone: 01872 252103
1. Policy Aim* Who is the strategy / policy / proposal / service function aimed at?
Guidance on the safe and accurate sampling of earlobe blood specimens for blood gas analysis in adult in-patients
2. Policy Objectives* Standardised care, technique to ensure patient and staff safety
3. Policy – intended Outcomes*
Standardised care
4. *How will you measure the outcome?
Audit
5. Who is intended to benefit from the policy?
Medical and nursing staff, patients
6a Who did you consult with
b). Please identify the groups who have been consulted about this procedure.
Workforce Patients Local groups
External organisations
Other
Please record specific names of groups
What was the outcome of the consultation?
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Are there concerns that the policy could have differential impact on:
Equality Strands: Yes No Unsure Rationale for Assessment / Existing Evidence
Age x
Sex (male, female, trans-gender / gender reassignment)
x
Race / Ethnic communities / groups
x
Disability -Learning disability, physical impairment, sensory impairment, mental health conditions and some long term health conditions.
x
Religion / other beliefs
x
Marriage and Civil partnership
x
Pregnancy and maternity
x
Sexual Orientation, Bisexual, Gay, heterosexual, Lesbian
x
You will need to continue to a f ull Equality Impact Assessment if the following have been highlighted:
7. The Impact
Please complete the following table. If you are unsure/don’t know if there is a negative impact you need to repeat the consultation step.
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You have ticked “Yes” in any column above and
No consultation or evidence of there being consultation- this excludes any policies
which have been identified as not requiring consultation. or
Major this relates to service redesign or development
8. Please indicate if a full equality analysis is recommended. Yes No
x
9. If you are not recommending a Full Impact assessment please explain why.
Signature of policy developer / lead manager / director
Date of completion and submission
Names and signatures of members carrying out the Screening Assessment
1. Dr Alexander Lomas
2. Human Rights, Equality & Inclusion Lead
Keep one copy and send a copy to the Human Rights, Equality and Inclusion Lead
c/o Royal Cornwall Hospitals NHS Trust, Human Resources Department, Knowledge Spa, Truro, Cornwall, TR1 3HD
Signed: Dr. Alexander Lomas
Date: 13 February 2018