Comparison between the phase angle and phase shift parameters to assess thoracoabdominal asynchrony in COPD patients.
Determining the presence of thoracoabdominal asynchrony in chronic obstructive pulmonary disease (COPD) patients is clinically relevant, but there is no consensus on the optimal parameters for performing this analysis. We assessed 22 COPD patients (FEV140 ± 10% predicted) and 13 healthy controls during rest and exercise with optoelectronic plethysmography (70% maximum workload) on a cycle ergometer. Thoracoabdominal asynchrony was calculated by using phase angle and phase shift parameters following a three-compartment model involving the upper and lower rib cages and abdomen. Patients were classified as having thoracoabdominal asynchrony (TAA+) or not (TAA-) based on control values (mean ± 2 SDs). The chest wall volume and compartmental contribution were also measured. Thoracoabdominal asynchrony was observed in the lower rib cage. The phase angle detected more TAA+ patients at rest (15 vs. 7 patients) and during exercise (14 vs. 8 patients) compared with the phase shift. TAA+ patients also presented a lower chest wall volume, lower rib cage contribution, and higher abdominal contribution to chest wall volume compared with the control and TAA- patients. Thoracoabdominal asynchrony was more detectable during rest and exercise using the phase angle parameter, and it was observed in the lower rib cage compartment, reducing the chest wall volume during exercise in patients with COPD.NEW & NOTEWORTHYThis study contributes to advance the knowledge over the previous lack of consensus on the assessment of thoracoabdominal asynchrony. We rigorously evaluated the related features that interfere in the measurement of the asynchrony (measurement tool, chest wall model and calculation parameter). Our results suggest that phase angle detects more suitably thoracoabdominal asynchrony that occurs on the lower ribcage and leads to a reduction in the chest wall volume during exercise in COPD patients.
Department of Physical Therapy, School of Medicine, University of São Paulo, São Paulo, Brazil.
Desiderio
http://orcid.org/0000-0002-2436-0102
D
Cano Porras
Department of Physical Therapy, School of Medicine, University of São Paulo, São Paulo, Brazil.
Adriana C
AC
Lunardi
Department of Physical Therapy, School of Medicine, University of São Paulo, São Paulo, Brazil.
Cibele C B
CCB
Marques da Silva
Department of Physical Therapy, School of Medicine, University of São Paulo, São Paulo, Brazil.
Denise M
DM
Paisani
Pulmonary Division, Heart Institute (InCor), School of Medicine, University of São Paulo, São Paulo, Brazil; and.
Rafael
R
Stelmach
Biomedical Engineering Laboratory, Department of Telecommunication and Control Engineering, School of Engineering, University of São Paulo, São Paulo, Brazil.
Henrique T
http://orcid.org/0000-0002-1595-1779
HT
Moriya
Department of Physical Therapy, School of Medicine, University of São Paulo, São Paulo, Brazil; cscarval@usp.br.
Celso R F
CRF
Carvalho
D000005:Abdomen / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology; D005080:Exercise Test / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010991:Plethysmography / Q000379:methods; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D015656:Respiratory Mechanics / Q000502:physiology*; D012146:Rest / Q000502:physiology; D035441:Thoracic Wall / Q000503:physiopathology
air trapping; chest wall; chronic obstructive pulmonary disease; exercise; thoracoabdominal asynchrony