New decade, new standards in spirometry
Here we are in the middle of 2020, with the SARS-CoV-19 pandemic affecting the whole world. Who could have guessed in 2019 how relevant the new Spirometry standards would become with this respiratory disease. Expiratory spirometry is a very important test during COVID-19 to monitor for lung damage in those affected by this respiratory virus.
Quality assurance – spirometer calibration/verification
Not only do we have a year where a respiratory disease is the most important reason for increased mortality globally, but we have a decade ahead where respiratory diseases will need to be effectively monitored. Another 10 years of monitoring the lung function of our patients and employees. What better way to kick off than with a fresh and improved globally accepted spirometry standards document to guide us on our way. There is so much that is new that I wondered where to start. Logically let’s start at the very beginning with calibration.
Calibration checks of the spirometer are required as part of quality assurance in spirometry. Calibration is not optional, it is compulsory and must be completed daily before conducting a spirometry test on a patient. In the past a simple volume calibration check was sufficient, but now a daily linearity check is mandated. Using the spirometry calibration syringe 3L of air is injected into the spirometer using varied flow rates. The difference between the syringe volume and the measured volume must be less than +/-3% (previously +/-3.5%) for the calibration check to be successful at each of the different flow rates.
Shockingly, some manufacturers still state that their devices do not require such controls at all. Another pitfall to daily calibration is that calibration syringes are sold as a separate accessory, so the customer doesn´t always feel it is a must. BEWARE! This is not correct. eMoyo bundles the ORCAwave spirometer together with a calibrated ORCA syringe and ORCA weather station.
Manufacturers are now required to provide an alert if calibration is ± 2 standard deviations from the mean calibration factor or ± 6% from the previous calibration factor.
Spirometry software must include the ability to generate a report of calibrations that includes the results of all verifications, the number of failed calibration verifications in each session, and the changes in calibration factors. This is known as a calibration log and allows the user to easily compare calibration results over time.
Whilst these points are not something the end-user needs worry about when looking to buy a new spirometer, check that the spirometer software meets all the technical specifications of the 2019 Spirometry Standards update.
Pre-calibrated spirometers cannot be recalibrated by the operator, but must still undergo a calibration verification. Manufacturers must specify the action to be taken if a pre-calibrated device fails the calibration verification. Remember to check the spirometer user manual to ensure you know what to do with your particular device if the calibration fails. Some general tips about how to manage a failed calibration check will be supplied in the next instalment. Watch this space for everything you need to know about spirometry and more in 2020.
Forever fascinated with spirometry
The eMoyoEMR software that drives the ORCAwave has always been compliant to perform linearity calibration checks and the software also stores all calibrations sequentially in one place. A 3 stroke linear calibration check is available for quick, accurate calibration checks. In the case where you need to re-calibrate the ORCAwave, we will assist you to do a 10 stroke re-calibration. The full instructions are available in the user manual, however, we are happy to assist you with performing this very important calibration when required.
- Graham BL, Steenbruggen I, Miller MR. (2019). Standardization of Spirometry 2019 Update. An Official American Thoracic Society and European Respiratory Society Technical Statement. American Journal of Respiratory and Critical Care Medicine Volume 200 Number 8 | October 15 2019. Retrieved from: https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1590ST accessed 10 November 2019.
- Miller, M. R., Hankinson, J., Brusasco, V., Burgos, F., Casaburi, R., Coates, A., Crapo, R., Enright, P., Van Der Grinten, C. P. M., Gustafsson, P., Jensen, R., Johnson, D. C., Macintyre, N., Mckay, R., Navajas, D., Pedersen, O. F., Pellegrino, R., Viegi, G. & Wanger, J. (2005). Standardisation of spirometry. European Respiratory Journal, 26, 319-338.
- Culver BH, Graham BL, Coates AL et al. American Thoracic Society Documents. (October 2017). Recommendations for a Standardised Pulmonary Function Report. An Official American Thoracic Society Technical Statement. American Journal of Respiratory and Critical Care Medicine, 196, 1463-1472.
References retrieved from https://www.thoracic.org/statements/resources/pft/standardized-pulmonary-function-report.pdf Accessed: 10 November 2019.