Neuroscience Research Australia, Randwick, New South Wales, Australia.
Prince of Wales Hospital, Randwick, New South Wales, Australia.
J Appl Physiol (1985). 2022 Nov 1;133(5):1192-1201. doi: 10.1152/japplphysiol.00064.2022. Epub 2022 Sep 15.
This study investigated sensations of breathing following tetraplegia. Fifteen people with chronic tetraplegia and fifteen healthy able-bodied controls matched for age, sex, height, and weight participated. Sensations of breathing were quantified by determining the threshold for detecting an added resistance during inspiration. In a separate task, the perceived magnitudes of six suprathreshold resistive loads were determined with a modified Borg scale. The detection threshold of 0.34 cmHO/L/s [standard deviation (SD) 0.14] in the tetraplegia group was higher than the 0.23 cmHO/L/s (SD 0.10) threshold for able-bodied controls ( = 0.004). Both participant groups perceived larger loads to be more effortful, with the Borg effort rating increasing linearly with the peak inspiratory pressure generated at each load. The relationship between Borg effort rating and peak inspiratory pressure was steeper in participants with tetraplegia than in able-bodied controls ( = 0.001), but there was no difference when pressure was divided by maximal inspiratory pressure ( = 0.95). Despite a higher detection threshold, the findings suggest that the perceived magnitude of a suprathreshold inspiratory load is not impaired in chronic tetraplegia and that load magnitude perception is related to the maximal, and not absolute, inspiratory muscle force. Sensations of breathing are thought to be impaired following chronic tetraplegia. The detection threshold for an added resistive load during inspiration was higher in people with tetraplegia than in healthy able-bodied participants. However, for inspiratory loads above the detection threshold, the perceived magnitude of a resistive load as a function of the peak inspiratory pressure was greater in tetraplegia. Load magnitude perception was comparable between participant groups when peak pressure was divided by maximal inspiratory pressure.
本研究调查了四肢瘫痪后的呼吸感觉。 15 名慢性四肢瘫痪患者和 15 名年龄、性别、身高和体重匹配的健康对照组参加了研究。 通过确定在吸气过程中检测到附加阻力的阈值来量化呼吸感觉。 在单独的任务中，使用改良的 Borg 量表确定了六个超阈值阻力负荷的感知幅度。 四肢瘫痪组的检测阈值为 0.34 cmHO/L/s（标准差 0.14），高于健康对照组的 0.23 cmHO/L/s（ = 0.004）。 两个参与者组都认为较大的负荷更费力， Borg 努力评分随每个负荷产生的吸气峰压线性增加。 与健康对照组相比，四肢瘫痪组的 Borg 努力评分与吸气峰压之间的关系更陡峭（ = 0.001），但当压力除以最大吸气压力时没有差异（ = 0.95）。 尽管检测阈值较高，但研究结果表明，超阈值吸气负荷的感知幅度在慢性四肢瘫痪中并未受损，并且负荷幅度感知与最大而不是绝对吸气肌力量有关。 人们认为，慢性四肢瘫痪后呼吸感觉受损。 在吸气过程中，四肢瘫痪患者的外加阻力负荷检测阈值高于健康对照组。 然而，对于超过检测阈值的吸气负荷，四肢瘫痪患者的吸气峰压与阻力负荷感知幅度的关系更大。 当将峰值压力除以最大吸气压力时，两组参与者之间的负荷幅度感知相当。
