An impulse oscillometry system is less efficient than spirometry in tracking lung function improvements after intravenous antibiotic therapy in pediatric patients with cystic fibrosis

Abstract

A literature search identified one retrospective study on the responsiveness of impulse oscillometry (IOS) in pediatric patients with cystic fibrosis. The aim of this prospective observational study was to assess this property in an adequately powered study after intravenous antibiotic therapy (IVAT) administered for an acute episode of pulmonary exacerbation. Spirometry and IOS were done on the same day as the start and the end of IVAT. Data from 34 patients' of mean age 11.9 years (range, 5-17 years) were studied. The mean FEV1 at the start and at the end of the IVAT was 73.1 ± 23.8% (range, 23.4-122%) and 88.3 ± 21.3% (range, 29.4-131%), respectively. The mean relative change (mean ± SD) was 20.2 ± 14.2% for FEV1 (ΔFEV1 ), -21.9 ± 23.8% for reactance at 5 Hz (ΔX5) and -13.4 ± 18.9% for resistance at 5 Hz (Δ R5) (all P-values <0.05). There was a weak but significant correlation between ΔFEV1 and ΔX5 (r =-0.473; p = 0.01). The magnitude of improvement of ΔX5 was not statistically different between patients with normal versus abnormal lung function at the start of IVAT. Furthermore, using ΔX5 alone as an outcome measure of IVAT efficiency resulted in a significant improvement in 44% of the patients, while it was 79% with ΔFEV1 . These results indicate that IOS may track changes after IVAT, but that this improvement may be insufficiently evaluated using IOS alone.

Investigating outcome measures for assessing airway clearance techniques in adults with cystic fibrosis: protocol of a single-centre randomised controlled crossover trial

“…Most literature is in other patient populations, such as asthma; however, there are some studies emerging using IOS as an endpoint for CF intervention evaluation. 27 28 …”

Impulse oscillometry at preschool age is a strong predictor of lung function by flow‐volume spirometry in adolescence

“…In studies evaluating asthmatics with these two measurements done at the same visit, IOS has shown similar diagnostic capacity and even better accuracy compared to FVS, but it may suffer from significant variability . Studies following up long‐term lung function reduction with IOS have given both promising and conflicting results . Recently, a Finnish group found modest but statistically significant correlations between IOS at 4 years of age and FVS at 13.5 years of age.…”

“…16 Studies following up longterm lung function reduction with IOS have given both promising 17 and conflicting results. 18 Recently, a Finnish group found modest but statistically significant correlations between IOS at 4 years of age and FVS at 13.5 years of age. 19 The authors underlined, that when measuring different aspects of respiratory function, the correlations can be expected to be modest at best.…”

Pediatric Pulmonologyyear in review 2015: Part 4

“…71 The use of impulse oscillometry to assess improvement in pulmonary exacerbation was studied in 34 patients with mean age of 11.9 years. 72 The mean relative change with treatment was 20.2 AE 14.2% for FEV1 (DFEV1), 21.9 AE 23.8% for reactance at 5 Hz (DX5) and À13.4 AE 18.9% for resistance at 5 Hz (D R5) (all P < 0.05). There was a weak but significant correlation between DFEV1 and DX5 (r ¼À0.473; P ¼ 0.01).…”

“…Infant pulmonary function testing has been hampered by a shortage of the sedative chloral hydrate; dexmedetomidine was found to be an acceptable alternative . The use of impulse oscillometry to assess improvement in pulmonary exacerbation was studied in 34 patients with mean age of 11.9 years . The mean relative change with treatment was 20.2 ± 14.2% for FEV1 (DFEV1), 21.9 ± 23.8% for reactance at 5 Hz (DX5) and −13.4 ± 18.9% for resistance at 5 Hz (D R5) (all P < 0.05).…”