Poddighe Diego, Van Hollebeke Marine, Clerckx Beatrix, Janssens Luc, Molenberghs Geert, Van Dyck Lisa, Muller Jan, Gunst Jan, Meersseman Philippe, Peetermans Marijke, Hermans Greet, Gosselink Rik, Langer Daniel
KU Leuven, Department of Rehabilitation Sciences, Research Group for Rehabilitation in Internal Disorders, B-3000, Leuven, Belgium; University Hospitals Leuven, Department of Intensive Care Medicine, Leuven, Belgium.
KU Leuven, Department of Rehabilitation Sciences, Research Group for Rehabilitation in Internal Disorders, B-3000, Leuven, Belgium; University Hospitals Leuven, Department of Intensive Care Medicine, Leuven, Belgium.
Aust Crit Care. 2025 May;38(3):101152. doi: 10.1016/j.aucc.2024.101152. Epub 2025 Jan 21.
Recent studies suggest that fast and deep inspirations against either low or high external loads may provide patients with weaning difficulties with a training stimulus during inspiratory muscle training (IMT). However, the relationship between external IMT load, reflected by changes in airway pressure swings (ΔPaw), and total inspiratory effort, measured by oesophageal pressure swings (ΔPes), remains unexplored. Additionally, the association between ΔPes, ΔPaw, and inspiratory muscle activations remains unclear.
The ai of this study was to compare ΔPes and ΔPaw and their relationship with inspiratory muscle activation in patients with weaning difficulties during different breathing conditions.
ΔPes and scalene, sternocleidomastoid, and parasternal intercostal muscles activation were recorded during the following conditions: 1) (proportional) pressure support ventilation; 2) unsupported spontaneous breathing; 3) low-load IMT (load: <10% maximal inspiratory pressure, PImax = 3 cmHO) executed with slow and deep inspirations (low-load slow) and 4) low-load IMT (load: <10% maximal inspiratory pressure, PImax = 3 cmHO) executed with fast deep inspirations (low-load fast); and 5) high-load IMT (load ∼ 30% PImax) executed with fast and deep inspirations. ΔPaw, end-inspiratory lung volume, and peak inspiratory flow were recorded during conditions 2-5. Variables were compared across conditions using mixed-model analysis. Spearman's rank correlations were calculated between inspiratory muscle activations and both ΔPes and ΔPaw.
Five patients (age: 68 ± 1 y; 20% male; PImax: 37 ± 7 cmHO [59 ± 23% predicted]; forced vital capacity: 0.66 ± 0.16 L [21 ± 6% predicted]) were included in the study. ΔPes values were 3-4 times larger than ΔPaw values during unsupported spontaneous breathing and IMT conditions. ΔPes, sternocleidomastoid activation, end-inspiratory lung volume, and peak inspiratory flow were larger during low-load fast IMT than during low-load slow IMT and unsupported spontaneous breathing but were similar between low-load fast and high-load IMTs. Inspiratory muscle activations correlated weakly to moderately with ΔPaw and moderately with ΔPes.
In five patients with weaning difficulties, low-load fast IMT provided a training stimulus similar to high-load IMT. Both yielded significantly higher training stimulus than low-load slow IMT and unsupported spontaneous breathing. These results should be considered in future trials comparing IMT with sham conditions.
NCT03240263 and NCT04658498.
最近的研究表明，在吸气肌训练（IMT）期间，针对低或高外部负荷进行快速而深度的吸气，可能会给存在撤机困难的患者提供一种训练刺激。然而，由气道压力波动变化（ΔPaw）反映的外部IMT负荷与通过食管压力波动（ΔPes）测量的总吸气努力之间的关系仍未得到探索。此外，ΔPes、ΔPaw与吸气肌激活之间的关联尚不清楚。
本研究的目的是比较存在撤机困难的患者在不同呼吸条件下的ΔPes和ΔPaw及其与吸气肌激活的关系。
在以下条件下记录ΔPes以及斜角肌、胸锁乳突肌和胸骨旁肋间肌的激活情况：1）（比例）压力支持通气；2）自主无辅助呼吸；3）低负荷IMT（负荷：<最大吸气压力的10%，PImax = 3 cmH₂O），采用缓慢而深度的吸气进行（低负荷慢速）；4）低负荷IMT（负荷：<最大吸气压力的10%，PImax = 3 cmH₂O），采用快速而深度的吸气进行（低负荷快速）；以及5）高负荷IMT（负荷约为30% PImax），采用快速而深度的吸气进行。在条件2至5期间记录ΔPaw、吸气末肺容积和吸气峰值流速。使用混合模型分析在不同条件下比较变量。计算吸气肌激活与ΔPes和ΔPaw之间的Spearman等级相关性。
五名患者（年龄：68±1岁；20%为男性；PImax：37±7 cmH₂O [59±23%预测值]；用力肺活量：0.66±0.16 L [21±6%预测值]）纳入本研究。在自主无辅助呼吸和IMT条件下，ΔPes值比ΔPaw值大3至4倍。在低负荷快速IMT期间，ΔPes、胸锁乳突肌激活、吸气末肺容积和吸气峰值流速比低负荷慢速IMT和自主无辅助呼吸期间更大，但在低负荷快速和高负荷IMT之间相似。吸气肌激活与ΔPaw呈弱至中度相关，与ΔPes呈中度相关。
在五名存在撤机困难的患者中，低负荷快速IMT提供了与高负荷IMT相似的训练刺激。两者产生的训练刺激均明显高于低负荷慢速IMT和自主无辅助呼吸。在未来比较IMT与假对照条件的试验中应考虑这些结果。
NCT03240263和NCT04658498。
