104 CLINICAL DIAGNOSTICS. 



Inspiratory dyspnea is observed: 



1. In a pure form in bilateral paralysis (paraplegia) of 

 the larynx and in severe cases of unilateral paralysis of the 

 organ (hemiplegia, roaring). It is characterized by the above 

 cited inspiratory dyspnea and the occurrence of a stenotic 

 laryngeal bruit. In less severe cases of roaring this symp- 

 tom can only be brought out by exercising the patient. The 

 act of expiration is performed without difficulty. 



2. In less pure form where a stenosis of the nasal pas- 

 sages, pharynx, larynx or trachea exists due to inflammatory 

 swellings, tumors, etc. In such cases a stenotic sound is 

 emitted at each inspiration and the expiration is more or less 

 difficult. 



3. In diseases of the bronchi and lungs preventing the 

 free entrance of air : bronchitis, pulmonary edema, pneu- 

 monia. 



i. Where the principal respiiatory muscle, the dia- 

 phragm, is inactive : rupture or inflammation, tympanitis. 



Expiratory dyspnea appears when the exit 

 cf the air from the lung is made difficult. In this case 

 the expiration ensues not alone passively, but the accessory 

 expiratory muscles actively assist. The 

 muscles aiding expiration are: the abdominal muscles (exter- 

 nal and internal oblique, straight abdominal muscle), the in- 

 ternal intercostals and triangularis. An expiratory 

 dyspnea is recognized by the following 

 symptoms : The expiration is prolonged and is attended 

 with pronounced movement of the abdominal wall (pumping 

 of the flanks). At first, a limited sinking of the thoracic walls 

 ensues from a relaxation of the diaphragm, then the abdominal 

 muscles become active (contract) and a furrow is formed 

 along the course of their insertion to the costal cartilages— 

 the so-called "heave line." The passive and active moments 

 of expiration can be plainly distinguished from each other, so 

 that the movement of the flank appears to be a double pump- 



