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Hi I am in the process or revamping my Lung Function test Policy and Procedure and have a couple of questions Can anyone confirm: 1. Should we or should we not test VC? 2. Does anyone have any figures, scoring system or percentages that they use as criteria for repeat testing or referral criteria? Please see but excuse my ramble below. Point 1: Should we record the VC in an Occupational Health Nurse setting? When I initially undertook spirometry training (circa 1990) we used to ask our patients to undertake 3 relaxed (VC) and then 3 forced (FVC) tests on the manual Vitalograph spirormeter. With the introduction of the newer electronic spirometer's I have continued this practice, however a colleague recently attended a course and was informed that there was no longer a requirement to undertake the relaxed (VC) test. However I am reluctant to drop this test from my procedure or policy without some medical endorsements, thus I seek your opinion please? I have looked at the following documents for guidance: * The HSE MS 25 Guidance simply states the testing of FEV1 and FVC as a minimum; * In the European Respiratory Journal 2005; 26: 511-522 - Standardisation of the measurement of lung volumes. I can find definitions of VC, namely IVC and EVC, but nothing in the way of relevance of this test in preliminary occupational health surveillance setting; * In the European Respiratory Journal 2005; 26: 948 - 968 - Interpretative strategies for lung function tests. It states that "an obstructive ventilatory defect is a disproportionate reduction of maximal air flow in relation to the maximal volume (i.e. VC). It implies airway narrowing during exhalation and is defined by a reduced FEV1/VC ratio." This document later says that VC, FEV1, FEV1/VC ratio and TLC (total lung capacity not used in the OH setting?), are the basic parameters used to properly interpret lung function, although FVC is often used in place of VC; * In the European Respiratory J 2005; 26: 319 - Standardisation of spirometry. It states that the FVC and FEV1 are the most important aspects of spirometry, yet later it adds that in some patients, a slow VC or IVC may provide a larger and more appropriate denominator for calculation of the FEV1/VC%. The latter document later discusses the VC manoeuvre and I can clarify that I have always undertaken the EVC as opposed to the IVC test. In our policy we predominantly use the VC, FVC, FEV1 and FEV1 ratio, but we also record and look at the FMF25-75 and PEF. As I understood it the VC and FVC results should be similar, however if the FVC was less than the VC by more that 200mls it may indicate a lower airway collapse often seen in obstructive airway disease. I have therefore always tested the VC, always undertaking this test first to help familiarise the patients with the procedure, I also understood that forced spirometry could cause respiratory muscle fatigue causing inaccurate recordings of the VC if undertaken post forced spirometry? Point 2: I am looking for some guidance on repeat testing and referral criteria. In our current policy we repeat the test again within one month if the results are "down on last test" but no amount of deterioration is given. We also refer our patients onto either an OH Physician or Dr P Cullinan at the Royal Brompton Hospital depending upon their history if there is a "significant downward trend, or there is signs of a combined, restrictive or obstructive disease pattern shown." Is there any guidance or figures you would suggest that I use for these deterioration categories so that I can make my policy and procedure auditable? I have always worked with the fact that: * VC, FVC and FEV1, FVC should be greater than 80% of their predicted normal values, and * FEV1 ratio and FMF25-75 should be greater than 70% of their predicted normal value. One of my colleagues seems to recall being told that 5% deterioration on these predicted percentages was the referable criteria. In the European Respiratory J 2005; 26: 948 - 968 - Interpretative strategies for lung function tests. It references and quotes numerous severity scores, the severity table given only looks at FEV1 and starts as mild in severity if the % predicted is less than 70 and very severe if the % predicted percent is less than 35, which does not relate to OH referral criteria. I therefore wondered if you were aware of any scoring criteria that could or should be applied in the occupational health setting to make my policy more auditable. May I take this opportunity to thank you all for any help and guidance you may be able to give? Yours sincerely Janet Elliot. MSc. CMIOSH. OHND. RGN. Occupational Health Adviser _____ Corazon Health Limited 5 - 6 The Mill Copley Hill Business Park Cambridge Road, Cambridge CB22 3GN Switchboard: 01223 834404 Fax: 01223 834412 Web: <http://www.corazonhealth.co.uk/> www.corazonhealth.co.uk Corazon Health Limited is registered in England and Wales; company number 4434615 The contents of this email are confidential and intended only for the addressee. If this email is received by you, and you are not the intended recipient, please notify us and destroy the received copy. RecycleSave Paper - Do you really need to print this e-mail? No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2599 - Release Date: 01/04/10 08:24:00 ******************************** Please remove this footer before replying. OCC-HEALTH ARCHIVES: http://www.jiscmail.ac.uk/lists/occ-health.html CONFERENCES AND STUDY DAYS: http://www.jiscmail.ac.uk/cgi-bin/filearea.cgi?LMGT1=OCC-HEALTH OCCUPATIONAL HEALTH NURSING EDUCATION http://www.aohne.org.uk No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.124/2599 - Release Date: 01/04/10 08:24:00 ******************************** Please remove this footer before replying. OCC-HEALTH ARCHIVES: http://www.jiscmail.ac.uk/lists/occ-health.html CONFERENCES AND STUDY DAYS: http://www.jiscmail.ac.uk/cgi-bin/filearea.cgi?LMGT1=OCC-HEALTH OCCUPATIONAL HEALTH NURSING EDUCATION http://www.aohne.org.uk