Reproducibility and effect of posture on impulse oscillation parameters in persons with spinal cord injury

Abstract

Background: The impulse oscillation system (IOS) offers significant value in the assessment of airway dynamics in persons with spinal cord injury (SCI) because of minimal patient effort but measurement reproducibility in SCI is unknown. Objective: To evaluate between-day reproducibility and the effect of posture on airway resistance [respiratory resistances at 5 Hz (R5) and 20 Hz (R20)] in subjects with tetraplegia, paraplegia and able-bodied controls. Methods: Ten subjects with tetraplegia, 10 subjects with paraplegia and 11 able-bodied individuals were evaluated using IOS. Three 30 second trials were obtained in each while in the seated and supine position on Day 1, and repeated on Day 2. Results: The within-day coefficient of variation (CV%) for R5 and R20 were comparable in the 3 study groups in the seated and supine positions. Compared to controls, the between-day CV% for the combined data was higher in subjects with tetraplegia and paraplegia for R5 seated, and was higher in subjects with tetraplegia for R5 supine. Conclusions: IOS has applicability to the study of within-day respiratory resistance in SCI. However, performing longer-term studies in subjects with tetraplegia and paraplegia may be problematic because of the greater variability for R5 when compared to able-bodied individuals.

Oscilometría de impulso en adultos: una prueba de función pulmonar complementaria

“…Se observó que la oscilometría de impulso tiene aplicabilidad en el estudio de la resistencia respiratoria en pacientes con lesión en la médula espinal. Sin embargo, se requieren estudios a largo plazo en pacientes con tetraplejía y paraplejía (32).…”

Bronchodilator effects of ipratropium bromide and albuterol sulfate among subjects with tetraplegia

“…A greater than 40% increase in sGaw, the suggested criterion for significant bronchodilation using plethysmography, 19 was seen in ten of twelve subjects (83%) following IB. A greater than 20% fall in respiratory resistance parameters, the threshold for identifying a significant fall in IOS parameters in the general population 20 and SCI population, 21 was found among subjects following IB as follows: R5 (9 of 12 subjects, 75%), R20 (7 of 12, 58%), and R5-R20 (6 of 12, 50%) ( Table 3).…”