RT Journal Article
SR Electronic
T1 Compression artifact free flow-volume loops used to establish objective measurements in patient effort with spirometry
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP p2131
VO 38
IS Suppl 55
A1 Kristoffer Neu
A1 Gusssan Koussa
A1 Loni Hart
A1 Nadia Stachowicz
A1 Damian Compa
YR 2011
UL http://erj.ersjournals.com/content/38/Suppl_55/p2131.abstract
AB Background: Flow-volume loops (FVL) measured by using pressure-compression volume plethysmography has been described in the literature and is commonly called compression artifact free flow-volume loops (FVLc). The utility of this technique has been to help demonstrate good patient effort and to help identify upper airway obstruction. There are no studies demonstrating measurable objective data to help confirm patient effort with FVLc.Goal: Our study looks to identify the utility of FVLc by trying to establish a percentage cut off point for FVLc peak expiratory flow and what normal flow should be at 25, 50, and 75% intervals of the FVLc that can demonstrate good patient effort.Methods: 76 patient's charts that had FVLc in our lab were randomly reviewed. We looked to see if the peak flow on the FVLc was 25% higher than the traditional FVL. We recorded the flow percentages at the 25, 50, and 75% intervals of each patient's FVLc. Patients were divided by having a peak flow greater than 25% (group A) or less than 25% (group B).Results: 57 subjects peak flows on FVLc were greater than 25% and 19 patients were less than 25%. Comparing groups, the flow at the 25% interval in group A were statistically higher (mean 0.58 vs 0.35, P=0.0001). All patients with peak flow greater than 25% had higher flow rates at the 25% and 50% flow intervals (P=0.0001).Conclusion: Evaluating patient effort with FVLc may be helpful if the peak flow is 25% greater than seen on traditional FVL and if the 25% interval flow is greater. Further study is needed to establish the validity of this technique.