A kind of device based on pressure differential theory is introduced to measure the physiological parameters of people's lungs. This device possesses the advantages of small size, low power consumption and easy handling. It is not only able to overcome the effect of humidity caused by thermal airflow sensor, but also able to conveniently realise the simultaneous measurement of airflow and pressure with high precision. For this purpose, a four-way tube is designed and fabricated. Detailed theoretical analysis and simulation are used to verify the correctness of the structure. The digital signal processing and complex programmable logic device system is used and corresponding algorithms for the lung function parameters are programmed. Then, the measuring error of system is analysed by the error theory. The accomplished device is calibrated in the National Institute of Metrology of China, and the maximum relative error between the standard and measured results is about 2.84%. Clinical trials indicate that when the vital capacity is 5800, the relative error between the standard system and this device is just 0.6%, which suggests that this device can measure the lung function parameters at a higher level.

References

1. 1)
  - 4. Skloot, G.S., Edwards, N.T., Enright, P.L.: ‘Four-year calibration stability of the EasyOne portable spirometer’, Respir. Care, 2010, 55, (7), pp. 873–877.
2. 2)
  - 10. Rosell, J., Webster, J.G.: ‘Signal-to-motion artifact ratio versus frequency for impedance pneumography’, IEEE Trans. Biomed. Eng., 1995, 42, (3), pp. 321–323 (doi: 10.1109/10.364521).
3. 3)
  - 2. Salas, T., Rubies, C., Gallego, C., et al: ‘Technical requirements of spirometers in the strategy for guaranteeing the access to quality spirometry’, Arch. Bronconeumol., 2011, 47, (9), pp. 466–499 (doi: 10.1016/j.arbres.2011.06.005).
4. 4)
  - 12. Baldwin, M.R., William, C., Wise, R.A., et al: ‘A cleaning and calibration method for the spiropro portable spirometer's pneumotachometer tube in a remote field study’, Respir. Care, 2010, 55, (4), pp. 443–452.
5. 5)
  - 6. Zlochiver, S., Arad, M., Radai, M.M., et al: ‘A portable bio-impedance system for monitoring lung resistivity’, Med. Eng. Phys., 2007, 29, (1), pp. 93–100 (doi: 10.1016/j.medengphy.2006.02.005).
6. 6)
  - 7. Laghrouche, M., Montes, L., Boussey, J., et al: ‘Low-cost embedded spirometer based on micro machined polycrystalline thin film’, Flow Meas. Instrum., 2011, 22, (2), pp. 126–130 (doi: 10.1016/j.flowmeasinst.2010.12.012).
7. 7)
  - 8. Rosell, J., Cohen, K.P., Webster, J.G.: ‘Reduction of motion artifacts using a two-frequency impedance plethysmograph and adaptive filtering’, IEEE Trans. Biomed. Eng., 1995, 42, (10), pp. 1044–1048 (doi: 10.1109/10.464380).
8. 8)
  - 9. Al-Salaymeh, A., Jovanović, J., Durst, F.: ‘Bi-directional flow sensor with a wide dynamic range for medical applications’, Med. Eng. Phys., 2004, 26, (8), pp. 623–637 (doi: 10.1016/j.medengphy.2004.06.002).
9. 9)
  - 5. Carspecken, C.W., Arteta, C., Clifford, G.D.: ‘TeleSpiro: a low-cost mobile spirometer for resource-limited settings’. 2013 IEEE Point-of-Care Healthcare Technologies (PHT), Bangalore, India, January 2013, pp. 16–18.
10. 10)
  - 1. Nelson, S.B., Lavange, L.M., Nie, Y., et al: ‘Questionnaires and pocket spirometers provide an alternative approach for COPD screening in the general population’, Chest, 2012, 142, (2), pp. 358–366 (doi: 10.1378/chest.11-1474).
11. 11)
  - 3. Schermer, T.R., Verweij, E.H., Cretier, R., et al: ‘Accuracy and precision of desktop spirometers in general practices’, Respiration, 2012, 83, (4), pp. 344–352 (doi: 10.1159/000334320).
12. 12)
  - 11. Gupta, S., Chang, P., Anyigbo, N., et al: ‘MobileSpiro: accurate mobile spirometry for self-management of asthma’. Proc. First ACM Workshop on Mobile Systems, Applications, and Services for Healthcare, Seattle, WA, USA, November 2011, pp. 1–6.

Design and experimental research for a new kind of lung function parameters measurement device

References

Related content