Influence of acclimatization time on barometric whole-body plethysmography in cats with lower airway disease.

Abstract

Barometric whole-body plethysmography (BWBP) is used as a noninvasive method to assess lung function in cats with lower airway disease (LAD). The duration of the acclimatization period in the measuring chamber varies between the studies. To assess the influence of acclimatization time on variables indicative of lung function. Twenty-four client-owned cats with LAD and 8 healthy cats. In the prospective case-control study for each cat, a 30-minute dataset was collected. Data for the three 10-minute periods were statistically compared. The variables pause (T1 median: 0.8, range: [0.7-1]; T3: 0.9 [0.8-1.1]; P ≤ .01), peak inspiratory flow (PIF; T1: 84.9 [71.6-112.7]; T3: 75 [63.6-108.3]; P ≤ .001), peak expiratory flow (PEF; T1: 53.2 [41.5-76.6]; T3: 42.5 [34.6-57.8]; P ≤ .01), and a quotient of PEF and expiratory flow at 50% expired volume (PEF/EF50; T1: 1.2 [1.1-1.4]; T3: 1.2 [1.1-1.5]; P ≤ .01) varied significantly between first and third time period in cats with LAD. In healthy cats PIF (T1: 76.4 [66.3-85.2]; T2: 69.5 [58.3-85.2]; P ≤ .01), PEF (T1: 40 [32.8-58.6]; T2: 34.3, [29.8-44.6]; P ≤ .01), and PEF/EF50 (T1: 13.1 [11.6-14.6]; T3: 13.6 [12.4-16.3]; P ≤ .01) changed significantly between first and second time period. Enhanced pause did not change significantly in either group. Acclimatization time has a significant influence on multiple variables in BWBP. Manual correction of the data for tidal breathing flow-volume loop might be necessary.