摘要: The respiratory system may be schematically divided into two parts: a gas exchanging organ — the lungs and pump that ventilates lungs. consists of centers control pump, nerves connecting to chest wall muscles displace it. diaphragm is most important muscle, accounting for about 60% tidal volume in supine subject. It thus possible decreased diaphragmatic force represents final common pathway development hypercapnic failure from variety conditions. Thus, assessment function useful confirm diagnosis impairment also guide therapeutic intervention. In connection with this, it necessary have suitable techniques testing muscle quantitate contractility.