Work of breathing and lung volume during forward leaning supported by the upper limbs

Chihiro Koga; Kyoshi Mase; Sachie Takashima; Kenta Yamamoto; Risako Mineoka; Kohei Ozaki

doi:10.1016/j.resp.2023.104070

Work of breathing and lung volume during forward leaning supported by the upper limbs

Respir Physiol Neurobiol. 2023 Jul:313:104070. doi: 10.1016/j.resp.2023.104070. Epub 2023 May 2.

Authors

Chihiro Koga¹, Kyoshi Mase², Sachie Takashima², Kenta Yamamoto³, Risako Mineoka⁴, Kohei Ozaki⁵

Affiliations

¹ Department of Rehabilitation, Itami Kousei Neurosurgical Hospital, 1 300 1 Nishino, Itami, Hyogo 664-0028, Japan. Electronic address: c.s5n_3w@outlook.jp.
² Department of Physical Therapy, Faculty of Nursing and Rehabilitation, Konan Women's University, 6-2-23, Morikita, Higashinada, Kobe 658-0001, Japan.
³ Department of Rehabilitation, Konan Medical Center, 1-5-16, Kamokogahara, Higashinada, Kobe, Hyogo 658-0064, Japan.
⁴ Department of Rehabilitation, Radiation First Hospital, 1-10-50, Kitahiyoshi, Imabari, Ehime 794-0054, Japan.
⁵ Ozaki Seminar, 1-1-141-1120,Kouyouchounaka, Higashinada, Kobe, Hyogo 658-0032, Japan.

PMID: 37141930
DOI: 10.1016/j.resp.2023.104070

Abstract

This study compared work of breathing (WOB) and the pressure time product (PTP) to verify whether WOB and PTP decrease in the forward-leaning posture compared with erect sitting. Seven healthy adults (two females and five males) adopted three sitting postures: upright, and two forward-leaning postures of 15° and 30°. The WOB was obtained using the modified Campbell diagram, and PTP was calculated as the time integral of the area between esophageal and chest wall pressure. End-expiratory lung volume and transpulmonary pressure were significantly increased in the 15° and 30° forward-leaning postures compared with erect sitting (p ≦ 0.05). End-inspiratory lung volume was significantly increased in the 30° forward-leaning posture compared to erect sitting (p ≦ 0.05). PTP and inspiratory resistive WOB were significantly lower in the 15° and 30° forward-leaning postures compared to erect sitting (p ≦ 0.05). Forward leaning increases lung volume, which may dilate the airways, decrease resistant WOB, and reduce respiratory muscle activity.

Keywords: Campbell diagram; Forward-leaning posture; Pressure time product; Work of breathing.

MeSH terms

Adult
Female
Humans
Lung Volume Measurements
Male
Posture / physiology
Respiration*
Upper Extremity
Work of Breathing* / physiology