From Public Assistance - Paris Hospital, Pitie-Salpetriere Hospital, Pneumology and Critical Care Department, Paris, France (M.D., B.-P.D., S.D., E.M., J.M., T.S., A.D.) Sorbonne University, Experimental and Clinical Neurophysiology Research Unit 1158, Paris, France (M.D., S.D., T.S., A.D.) St. Michael's Hospital, Li Ka Shing Knowledge Institute, Keenan Research Centre, Toronto, Ontario, Canada (M.D., L.B.) Medicine Department, Pneumology Department, Hotel Dieu Hospital, Montreal University Hospital Center, Montréal, Québec, Canada (B.-P.D.) Montreal University Hospital Center Research Center, Montréal, Québec, Canada (B.-P.D.) the Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada (E.G., L.B.) the Department of Medicine, Division of Respirology, University Health Network and Mount Sinai Hospital, Toronto, Ontario, Canada (E.G., S.V.).
Anesthesiology. 2020 May;132(5):1114-1125. doi: 10.1097/ALN.0000000000003191.
The assessment of diaphragm function with diaphragm ultrasound seems to bring important clinical information to describe diaphragm work and weakness. When the diaphragm is weak, extradiaphragmatic muscles may play an important role, but whether ultrasound can also assess their activity and function is unknown. This study aimed to (1) evaluate the feasibility of measuring the thickening of the parasternal intercostal and investigate the responsiveness of this muscle to assisted ventilation; and (2) evaluate whether a combined evaluation of the parasternal and the diaphragm could predict failure of a spontaneous breathing trial.
First, an exploratory evaluation of the parasternal in 23 healthy subjects. Second, the responsiveness of parasternal to several pressure support levels were studied in 16 patients. Last, parasternal activity was compared in presence or absence of diaphragm dysfunction (assessed by magnetic stimulation of the phrenic nerves and ultrasound) and in case of success/failure of a spontaneous breathing trial in 54 patients.
The parasternal was easily accessible in all patients. The interobserver reproducibility was good (intraclass correlation coefficient, 0.77 (95% CI, 0.53 to 0.89). There was a progressive decrease in parasternal muscle thickening fraction with increasing levels of pressure support (Spearman ρ = -0.61 [95% CI, -0.74 to -0.44]; P < 0.0001) and an inverse correlation between parasternal muscle thickening fraction and the pressure generating capacity of the diaphragm (Spearman ρ = -0.79 [95% CI, -0.87 to -0.66]; P < 0.0001). The parasternal muscle thickening fraction was higher in patients with diaphragm dysfunction: 17% (10 to 25) versus 5% (3 to 8), P < 0.0001. The pressure generating capacity of the diaphragm, the diaphragm thickening fraction and the parasternal thickening fraction similarly predicted failure or the spontaneous breathing trial.
Ultrasound assessment of the parasternal intercostal muscle is feasible in the intensive care unit and provides novel information regarding the respiratory capacity load balance.
膈肌超声评估似乎为描述膈肌工作和无力提供了重要的临床信息。当膈肌薄弱时，膈外肌可能发挥重要作用，但超声是否也能评估其活动和功能尚不清楚。本研究旨在：（1）评估测量胸肋旁肋间肌厚度的可行性，并研究该肌肉对辅助通气的反应性；（2）评估胸肋旁和膈肌的综合评估是否能预测自主呼吸试验的失败。
首先，对 23 名健康受试者进行了胸肋旁的探索性评估。其次，在 16 名患者中研究了胸肋旁对几种压力支持水平的反应性。最后，在 54 名患者中，比较了存在或不存在膈肌功能障碍（通过膈神经磁刺激和超声评估）以及自主呼吸试验成功/失败时的胸肋旁活动。
所有患者均能轻松触及胸肋旁。观察者间的可重复性良好（组内相关系数为 0.77（95%可信区间，0.53 至 0.89）。随着压力支持水平的增加，胸肋旁肌肉增厚分数逐渐下降（Spearman ρ=-0.61[95%可信区间，-0.74 至-0.44]；P<0.0001），并且胸肋旁肌肉增厚分数与膈肌产生压力的能力呈负相关（Spearman ρ=-0.79[95%可信区间，-0.87 至-0.66]；P<0.0001）。膈肌功能障碍患者的胸肋旁肌肉增厚分数较高：17%（10 至 25）与 5%（3 至 8），P<0.0001。膈肌产生压力的能力、膈肌增厚分数和胸肋旁增厚分数同样可以预测自主呼吸试验的失败。
在重症监护病房，超声评估胸肋旁肋间肌是可行的，并提供了关于呼吸能力负荷平衡的新信息。
