Thoracoabdominal asynchrony: Two methods in healthy, COPD, and interstitial lung disease patients

by Mayra Caleffi Pereira, Desiderio Cano Porras, Adriana Claudia Lunardi, Cibele Cristine Berto Marques da Silva, Renata Cléia Claudino Barbosa, Letícia Zumpano Cardenas, Renata Pletsch, Jeferson George Ferreira, Isac de Castro, Celso Ricardo Fernandes de Carvalho, Pedro Caruso, Carlos Roberto Ribeiro de Carvalho, André Luis Pereira de Albuquerque

Thoracoabdominal asynchrony is the nonparallel motion of the ribcage and abdomen. It is estimated by using respiratory inductive plethysmography and, recently, using optoelectronic plethysmography; however the agreement of measurements between these 2 techniques is unknown. Therefore, the present study compared respiratory inductive plethysmography with optoelectronic plethysmography for measuring thoracoabdominal asynchrony to see if the measurements were similar or different.

27 individuals (9 healthy subjects, 9 patients with interstitial lung disease, and 9 with chronic obstructive pulmonary disease performed 2 cycle ergometer tests with respiratory inductive plethysmography or optoelectronic plethysmography in a random order. Thoracoabdominal asynchrony was evaluated at rest, and at 50% and 75% of maximal workload between the superior ribcage and abdomen using a phase angle.

Thoracoabdominal asynchrony values were very similar in both approaches not only at rest but also with exercise, with no statistical difference. There was a good correlation between the methods and the Phase angle values were within the limits of agreement in the Bland-Altman analysis.

Thoracoabdominal asynchrony measured by optoelectronic plethysmography and respiratory inductive plethysmography results in similar values and has a satisfactory agreement at rest and even for different exercise intensities in these groups.