Acute effects of different inspiratory efforts on ventilatory pattern and chest wall compartmental distribution in elderly women

It is not completely understood how aging affects ventilatory kinematics and what are the mechanisms adopted by the elderly population to overcome these structural modifications. Given this, the aim of this study was to evaluate the acute effects of different inspiratory efforts on ventilatory pattern and chest wall compartmental distribution in elderly women.

The study assessed the following variables: tidal volume (Vt), total chest wall volume (Vcw), pulmonary rib cage (Vrcp%), abdominal rib cage (Vrca%) and abdominal compartment (Vab%) relative contributions to tidal volume. These variables were assessed during quiet breathing, maximal inspiratory pressure maneuver (MIP), and moderate inspiratory resistance (MIR; i.e., 40% of MIP).

A total of 22 young women (age: 23.9±2.5 years) and 22 elderly women (age: 68.2±5.0 years) participated in this study. It was possible to show that during quiet breathing, Vab% was predominant in the elderly group (p<0.001), in the young group, however, Vab% was similar to Vrcp% (p=0.095). During MIR, Vrcp% was predominant in the young group (p<0.001) and comparable to Vab% in the elderly (p=0.249). When MIP was imposed, both groups presented a predominance of Vrcp%.

In conclusion, there are differences in abdominal kinematics between young and elderly women during different inspiratory efforts. In the elderly, during moderate inspiratory resistance, the pattern is beneficial, deep, and slow. Although, during maximal inspiratory resistance, the ventilatory pattern seems to predict imminent muscle fatigue.