Fujiyasu Kakizaki

Instantaneous changes in respiratory function induced by passive pelvic suspension in the supine position in relation to increased diaphragm excursion

[Purpose] This study aimed to introduce an approach of pelvic suspension (PS) using sling cords and to obtain evidence for changes in respiratory function of healthy subjects. [Subjects and Methods] Subjects were 25 healthy men. In the supine position, with hip and knee joints flexed at 90°, the subjects’ pelvises were suspended with sling belts. Diaphragm excursion, respiratory function, and respiratory comfort in these postures were measured using ultrasonography, respirometry, and visual analog scale (VAS), respectively. [Results] When the pelvis was passively suspended with sling cords, the diaphragm moved 5 mm cranially and diaphragm excursion showed an instantaneous increase compared with the control. The tidal volume (VT) showed an increase and the respiration rate (RR) showed a decrease. The extent of diaphragm excursion was correlated with changes in VT under the control and PS conditions. Independent measurements of pulmonary function revealed that PS reduced the expiratory reserve volume, being correlated positively and negatively to increases in vital and inspiratory capacities, respectively. Furthermore, VAS values for respiratory ease were greater with PS than with the control. [Conclusion] These results suggest that PS effectively changed diaphragm excursion and respiratory function, leading to ease of breathing (i.e., deep and slow respiration).

The relationship between thoracic configuration and changes in volumes of hemithoraces in upright sitting

[Purpose] Some patients with respiratory disease exhibit asymmetrical movement of the thorax. The purpose of this study was to investigate the relationship of thoracic configuration with changes in thoracic volume in 13 sedentary healthy men. [Subjects and Methods] In upright sitting, 84 reflective markers were placed on the anterior and posterior aspects of the trunk to record thoracic volume during quiet and volitional deep breathing. Using a three-dimensional motion analyzer, the difference in volume within the upper and lower hemithoraces was measured. For calculation of the thoracic volume six imaginary hexahedra were visualized for the upper and lower thorax using four reflective markers for each on the anterior and posterior aspects of the thorax. Each hexahedron was then divided into three imaginary triangular pyramids to calculate positional vectors. Finally, the volume for both the hexahedra and triangular pyramids was calculated. Four thoracic volumes were obtained. [Results] The findings showed that the left upper and right lower hemithorax yielded significantly larger thoracic volumes. [Conclusion] In conclusion the left upper and right lower hemithoraces were found to expand more than their corresponding sides. Understanding the characteristics of thoracic excursion during quiet and volitional deep breathing could be of value in assessment and instruction of breathing techniques to patients.