Konventionell spirometri och minispirometri : Hur skiljer sig resultaten i ett kliniskt material?

Sammanfattning: More spirometric analysis needs to be performed in order to discover lung diseases like chronic obstructive pulmonary disease (COPD). A mini spirometer can quickly and easily be used for screening. Today, a plethysmograph is used at the hospital in Helsingborg at the department of clinically physiology. However, they also have a mini spirometer, which is seldom used. By comparing the mini spirometer with the reference (the plethysmograph), results may indicate whether it could be possible to use the mini spirometer for screening or in other situations at the department when immediate and reliable information about lung function is needed. As a total of 45 patients participated in this study. All were examined with the mini spirometre after the conventional spirometry using a reversibility test. Of these there were 41 who were used in the study. After the conventional spirometry, they performed 4 - 7 forced expirations followed by inspirations. Theparameters investigated were FVC (forced vital capacity), FEV1 (forced expiratory vital capacity in 1 second), and FEV1/FVC. For the conventional spirometry slow VC was used, according to clinical routine. With 95 % CI the mean ・} SD was calculated to be for FVC between the 2 methods -0,19 ・} 0,30 litre. For FEV1 the results were 0,04 ・} 0,13 litre and for FEV1/FVC 0,05 ・} 0,05 litre. Paired t-test resulted for FVC in t = 4,1. FEV1 gave t= 1,79 and for FEV1/FVC was t= 6,28. The t-values were compared with t critical= 2,03 which were taken from a table. A lower t- value than t critical suggests that the methods are comparable. When comparing the difference between the both methods, FEV1 agreed well, while FVC and FEV1/FVC was too large.