Schönhofer B
Abteilung für Pneumologie, Internistische Intensivmedizin und Schlafmedizin, Krankenhaus Oststadt-Heidehaus, Klinikum Region Hannover, Podbielskistr. 380, 30659, Hannover, Deutschland,
Med Klin Intensivmed Notfmed. 2015 Apr;110(3):182-7. doi: 10.1007/s00063-014-0373-0. Epub 2014 Jun 19.
Chronic respiratory failure is caused by insufficiency of the inspiratory muscles, i.e. mainly the diaphragm, which represents the so-called "respiratory pump". Insufficiency of the respiratory pump causes hypercapnia.
Diseases with chronic hypercapnia are characterized by reduced survival. Mechanical ventilation-mostly applied as noninvasive mechanical ventilation (NIV)-improves ventilation and unloads the inspiratory muscles.
Strong evidence supports the use of domiciliary NIV already in mild degrees of chronic respiratory failure caused by neuromuscular diseases, thoracic restrictions and obesity hypoventilation. In these diseases long-term NIV improves both physiological parameters (such as blood gases) and clinical outcome, e.g. exercise capacity, right heart dysfunction, sleep quality, disease-specific aspects of health-related quality of life (HRQL) and survival rate. In contrast, its influence on long-term survival in chronic obstructive pulmonary disease (COPD) patients is not clearly proven. Prescription of home NIV in COPD should therefore be restricted to severe degrees of chronic respiratory failure. Finally, there is an indication for domiciliary NIV in patients after prolonged weaning from mechanical ventilation. This paper elaborates underlying pathophysiology, diseases and how NIV works in chronic hypercapnic respiratory failure.
慢性呼吸衰竭由吸气肌功能不全引起，主要是膈肌，膈肌构成所谓的“呼吸泵”。呼吸泵功能不全导致高碳酸血症。
慢性高碳酸血症疾病的特点是生存率降低。机械通气——大多采用无创机械通气（NIV）——可改善通气并减轻吸气肌负担。
有力证据支持在由神经肌肉疾病、胸廓受限和肥胖低通气引起的轻度慢性呼吸衰竭中使用家庭无创通气。在这些疾病中，长期无创通气可改善生理参数（如血气）和临床结局，如运动能力、右心功能不全、睡眠质量、与健康相关生活质量（HRQL）的疾病特异性方面以及生存率。相比之下，其对慢性阻塞性肺疾病（COPD）患者长期生存的影响尚未得到明确证实。因此，COPD患者家庭无创通气的处方应限于重度慢性呼吸衰竭。最后，对于机械通气长时间撤机后的患者有家庭无创通气的适应证。本文阐述了潜在的病理生理学、疾病以及无创通气在慢性高碳酸血症呼吸衰竭中的作用机制。
