In healthy individuals the inspiration is the result of a coordinated movement of the thoracic compartments and the relaxation of the diaphragm muscle. Yamaguti, et al. [16
] noted higher mortality in patients with COPD with low mobility of the diaphragm muscle when compared to individuals without diaphragmatic dysfunction. These results reinforce the need for targeted studies for the assessment of Thoracoabdominal mobility in this group of patients, the deep inspiration being cited in clinical studies [12
], though widely used in clinical practice.
In addition, the change due to alveolar pathophysiology promotes a chronic airway closure. With deep inspiration some tension is produced and transmitted to the bronchus
, preventing small peripheral Airways enter into collapse, allowing full air outlet within the lung. Thus, lung capacity and maximum breathing capacity are improved and the residual volume is reduced, thus correcting the anaerobic situation [17
The results of this study demonstrate that patients with COPD have a higher asynchrony during inspiration deep compartment in relation to healthy. In this study, normal ranges were defined using as reference the AF values obtained in the control group (CG) composed of healthy individuals matched by age [15
Although traditionally believe that movements of the rib cage during the respiratory cycle accompany changes in lung volume, this is not always the case in patients with obstructive lung disease. The compartment found [18
] asynchrony in this study was in relation to the lower chest compartments in relation to the abdomen, suggesting a delay in the movement of the chest below in relation to other compartments (represented by the negative value obtained). This delay can be explained by altered respiratory mechanics in patients with COPD, due to a downgrading of the diaphragmatic domes, resultantede a lower abdominal pressure and, consequently, in less lower rib cage expansion leading to decreased mobility [20
]. we can suggest that the asynchronicity of the CTI in patients with COPD is a stabilisation mechanism of the ring structure, more than move so uncoordinated with the other two magazines and that efficiency of the diaphragm to expand the CTI may be lower than in healthy individuals [1
If we consider the mechanisms behind thoraco-abdominal synchrony that are explored via OEP [1
], and which take place through the coordinated actions of the compartments, our results may provide evidence that the abdominal rib cage is what contributes the least to the total tidal volume of the respiratory cycle in patients with COPD. Our results are consistent with those reported by Calverley, et al. particularly in terms of their assertion that pulmonary hyperinflation also contributes to a structural change in the rib cage muscles because they are stretched, their strength and contraction capacity are reduced. This, in turn, reduces the mobility
of the abdominal rib cage [22
Other studies have shown that patients with COPD who presents asynchrony often contracts the abdominal muscles during expiration [24
] and the relaxation of these muscles is done gradually during inspiration [7
], causing the CTI tend to retract earlier inspiration and slowing its expansion in the inspiratory phase and may be then an increase in recruitment and activation of the inspiratory muscles don't diafragmáticos to compensate for this disadvantage [21
] mechanics, which cannot be mistakenly confused by observing the abdominal compartment contrubuição increase in this population of patients.
Gorman, et al. evaluated both the zone of apposition, which was measured using ultrasonography, and ribcage diameters, which were measured using magnetometers. They observed different patterns of behavior of the abdominal rib cage in cases of dysfunctions of the diaphragm in COPD patients [26
]. Similar results were found by Alliveti, et al. who used the three-dimensional OEP method for the first time. The authors reported that COPD patients who presented asynchrony of the abdominal rib cage while at rest were more prone to early-onset hyperinflation during physical exercise than those who did not present asynchrony [1
]. These results corroborate with our findings, even if we have not assessed directly to lung hyperinflation of our patients, once the asynchrony was only observed in COPD group CTI and the lack of correlation of FVC with the CTI contrubuição almost presents significance, which may present greater relevacia and if the sample number was bigger.
With regard to the contribution in the total tidal volume compartment, our results showed that the upper rib cage contributes less to tidal volume in patients with COPD compared to healthy individuals. These findings, according to Bernarg, et al. can be explained by anatomical changes of respiratory muscles in these patients, such as sarcopenia and decreased contractility of this [27
] muscles, which in turn can lead to a decrease in the contribution of this upper chest compartment, in the generation of tidal volume in individuals with COPD [28
About the Association of obstruction of the air flow with the assincroniatoracoabdominal, there is no consensus in the literature, because, while some studies might associate the VEF1com reduction commitment of diaphragm muscle [30
] mobility, but also of getting a relationship between diaphragmatic dysfunction and air entrapment, [32
] others like Priori, et al. [15
] found no correlation between the severity of the obstruction and the presence of assincroniatoracoabdominal. These data are in agreement with our findings.
In addition to these aspects, other factors that deserve more attention in the synchronic analysis of Thoracoabdominal COPD patients are respiratory muscle dysfunction and pulmonary hyperinflation [2
]. However it is worth remembering that the inspiration for the lower rib cage is not performed for only [31
] diaphragm muscle contraction.
Further studies on the behavior of the ATA in situations of exacerbation and in respiratory procedures common in clinical practice, especially of respiratory physiotherapy, could contribute to a better understanding about the improved sync and Thoracoabdominal motion in patients with COPD.