Intra-session and inter-session variability of nitric oxide pulmonary diffusing capacity in adults with cystic fibrosis

Publication date: Available online 3 August 2017 Source:Respiratory Physiology & Neurobiology Author(s): Thomas Radtke, Christian Benden, Marion Maggi-Beba, Susi Kriemler, Ivo van der Lee, Holger Dressel We evaluated the intra-session and inter-session variability of the diffusing capacity of nitric oxide (DLNO), carbon monoxide (DLCO), membrane diffusing capacity for carbon monoxide (DMCO) and pulmonary capillary blood volume (Vc) in patients with cystic fibrosis (CF). Patients performed single-breath diffusing capacity measurements during all of 3 consecutive study visits. Precision of gas diffusing parameters was quantified by within- subject standard deviation (SDws) and coefficient of variation (CV). Intra-session and inter-session reproducibility was determined by SDws*2.77. 15 clinically stable patients were included. The intra-session precision of gas diffusing parameters improved over the study visits. The inter-session SDws for DLNO, DLCO, DMCO, and Vc was 4.8, 1.3, 2.4, and 4.3, respectively. Reproducibility was 13.3, 3.8, 6.7 and 12.0mL.min−1.mmHg−1; CV was 4.4, 4.7, 4.4 and 5.8%, respectively. The intra-session variability of DLNO, DLCO, DMCO and Vc improves with breath-hold maneuver training in test-naïve patients with CF, indicating a learning effect. Inter-session reproducibility data are lower than those previously reported in healthy subjects.
Source: Respiratory Physiology and Neurobiology - Category: Respiratory Medicine Source Type: research