Exploration of quality criteria for the detection of peak inspiratory flow under different resistance conditions.

BACKGROUND: At present, robust quality criteria and methods for the assessment of Peak inspiratory flow meter performance are lacking. OBJECTIVE: A standard flow-volume simulator for quality control analyses of an inhalation assessment device was utilized with different simulated resistance levels in order to propose a quality testing method and associated standard for this device type. METHODS: A standard flow-volume simulator was utilized to assess the performance of an In-Check DIAL® (Device I) and an intelligent inhalation assessment device (Device P) at a fixed volume and flow rate. Indices used to evaluate these two instruments included repeatability, accuracy, linearity, and impedance. RESULTS: Both devices exhibited good repeatability (<± 3 L/min). The difference between test results and standard simulator values for Device P was less than ± 5 L/min at resistance level R1 but higher than ± 5 L/min at resistance levels R2-5, while Device I were greater than 5 L/min at all resistance levels. The relative error for Device P was <± 10% at resistance levels R1, R2, and R4, but > 10% at resistance levels R3 and R5. The relative error values for Device I at all five resistance levels were > 10%. Device P passed the linearity test at the R2 resistance level, while Device I partially passed the linearity test at all five resistance levels. CONCLUSION: Standard monitoring methods and standards provide a valuable approach to the more reliable clinical assessment and application of these instruments.

Quality inspection and result analysis of the spirometer calibration cylinder.

BACKGROUND: To understand the accuracy of volume calibration syringes used in China and compare the difference between new and old volume calibration syringes, technical testing was performed on volume calibration syringes in clinical lung function instruments. MATERIALS AND METHODS: A standard validator device (Model 1180, Hans Rudolph, USA) was used to perform leak testing and volume accuracy testing for calibration syringes. Sixteen volume calibration syringes from 8 brands (CareFusion in Germany, Vyaire in Germany, Yaeger in Germany, Vitalograph in the United Kingdom, MGC Diagnostics in the United States, U-Breath in Zhejiang, China, Wendi in Ningbo, Zhejiang, and Boya in Ningbo, China) were tested. RESULTS: A total of 75% (12/16) of the volume calibration syringes passed the pressure decay leak test, 69% (11/16) of the volume calibration syringes passed the volume accuracy and repeatability test, and 56% (9/16) passed both tests; there was no significant difference in the total passing of the new and old volume calibration syringe quality tests (P > 0.05). CONCLUSIONS: A standard validator device should be used for both leakage tests and volume accuracy and repeatability tests to ensure the reliability of volume calibration syringes. It is suggested that the quality verification of volume calibration syringes should be regularly conducted to ensure the accuracy of the pulmonary function tests.