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

Abstract

BackgroundThoracoabdominal 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.Methods27 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.ResultsThoracoabdominal 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.ConclusionThoracoabdominal 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.

The Importance of Respiratory Rate Monitoring: From Healthcare to Sport and Exercise

“…Similar performances were found when comparing thoracoabdominal asynchrony measured with RIP and optoelectronic plethysmography (the reference system for measuring compartmental volumes [156]) in healthy individuals and patients with COPD and interstitial lung disease [155]. However, the agreement between the two techniques was higher at rest and during moderate exercise compared to heavy exercise, where a wide variability in the phase angle was observed [155].…”

“…Respiratory inductive plethysmography is a classical technique used to compute thoracoabdominal asynchrony with wearable sensors, and consists of two elastic cloth bands containing insulated wires encircling the rib cage and the abdomen [24]. Similar performances were found when comparing thoracoabdominal asynchrony measured with RIP and optoelectronic plethysmography (the reference system for measuring compartmental volumes [156]) in healthy individuals and patients with COPD and interstitial lung disease [155]. However, the agreement between the two techniques was higher at rest and during moderate exercise compared to heavy exercise, where a wide variability in the phase angle was observed [155].…”

“…A smart garment designed for measuring physiological signs of dyspnea would benefit from the integration of strain sensors situated in specific locations of the trunk. Indeed, sensor redundancy improves the accuracy of f R and V T measurements [24,153,154], and may help detect other signs observed in patients with dyspnea such as the temporal thoracoabdominal asynchrony between the movements of the thoracic and abdominal compartments [155,156]. Thoracoabdominal asynchrony is often computed by means of the phase angle analysis, is higher during exercise compared to rest, and increases with exercise intensity [155].…”

“…Indeed, sensor redundancy improves the accuracy of f R and V T measurements [24,153,154], and may help detect other signs observed in patients with dyspnea such as the temporal thoracoabdominal asynchrony between the movements of the thoracic and abdominal compartments [155,156]. Thoracoabdominal asynchrony is often computed by means of the phase angle analysis, is higher during exercise compared to rest, and increases with exercise intensity [155]. Respiratory inductive plethysmography is a classical technique used to compute thoracoabdominal asynchrony with wearable sensors, and consists of two elastic cloth bands containing insulated wires encircling the rib cage and the abdomen [24].…”

Contact-Based Methods for Measuring Respiratory Rate

“…Systems have been tested during an incremental running test on a treadmill, and multiple periods of recovery [10], and during cycling [184]. On patients with respiratory issues, similar thoraco-abdominal asynchronies and fR values were found when comparing a two-coil inductive sensor with a motion capture system (requiring complex model and markers to be attached on the chest [185]) both during quiet breathing and exercise [186]. Good performance have also been reported when testing a smart t-shirt instrumented by inductive sensors on healthy subjects [187].…”