*Breathing Monitoring and Pattern Recognition with Wearable Sensors DOI: http://dx.doi.org/10.5772/intechopen.85460*

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C*<sup>T</sup>* = \_\_\_\_ dV

<sup>C</sup>*<sup>L</sup>* <sup>=</sup> \_\_\_ dV

C*LT* = \_\_\_\_ dV

*<sup>R</sup>* <sup>=</sup> <sup>8</sup>η<sup>L</sup> \_\_\_

**2.2 Muscles involved in breathing and their functions**

Abdominal muscle is also important for coughing [16].

by Eq. (5).

the radius of the tubes.

**patterns**

dP*<sup>T</sup>*

dP*<sup>L</sup>*

dP*LT*

*r*<sup>4</sup> (5)

Breathing also involves air diffusion, exchange from a more concentrated to a less concentrated medium. Poiseuille's law governs the flow resistance as expressed

Where *R* is the flow resistance, L is the length, η is the viscosity of air, and *r* is

The diaphragm is the most important muscle of inspiration. When it contracts, there is a decrease in intrapleural pressure and an increase in lung volume [13]. Simultaneously, an increase in abdominal pressure is transmitted to the chest through the apposition zone to expand the lower thoracic cavity. When the diaphragm contracts, the lower rib cage expands. One may observe the bucket handle movement that causes an increase in thorax transverse diameter due to the elevation of the ribs during inspiration [15]. Elevation and sternum forward movement during inspiration causes the increase of thorax anteroposterior diameter. Diaphragm contraction also contributes to increasing the longitudinal thorax diameter [12]. Scalene muscle, sternocleidomastoid muscle, and intercostal muscle are inspiration auxiliary muscles. During forced expiration, the abdominal muscles contract, and the diaphragm is pushed upward, thus causing a decrease in chest diameters.

**2.3 Different etiologies, types, and characteristics of pathological respiratory** 

If structural and/or functional changes occur, then adequate air transport to and from the lungs can be compromised. There are different etiologies, types, and pathological respiratory patterns in which wearable systems may assist in the characterization of movement patterns [1]. This capacity helps in the analysis of the

Thoracic mobility is related to the integrity of the nerve pathways and respiratory muscles [13]. In clinical practice, thoracic and abdominal amplitude measurements during respiratory movement may provide information on changes in the respiratory system or eventual diseases [17]. Some paradoxical movements may occur when patients present weakness, muscle paralysis, or chronic obstructive pulmonary disease (COPD), with pulmonary hyperinflation, among other commitments [18]. Another example is Cheyne-Stokes breathing, which is a type of central sleep apnea with an unstable breathing pattern throughout the night. It can cause changes in respiratory frequency and depth of patients with congestive heart failure [19].

health condition of patients, providing important additional information.

**Figure 1** shows the main structures and processes involved in breathing.

(2)

(3)

(4)

**54**

Other impairments may cause changes in the thoracic and abdominal mobility relation such as dyspnea, orthopnea, alternate breathing, forced expiration, etc. Wearable systems capable of monitoring the contribution of different muscles and changes in mobility patterns can help monitor the evolution of the respiratory functional condition of a person.
