RESPIRATORY APPARATUS. 99 



sages, pharynx, larynx or trachea exists due to inflammatory 

 swelhngs, 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. ^^'here the principal respiratory muscle, the dia- 

 phragm, is inactive : rupture or inflammation, tympanitis. 



Expiratory dyspnea. This occurs when the 

 exit of the air from the lung is made difficult. In this case 

 the expiration ensues not alone passively, but the accessory 

 expiratory muscles a c t i v e 1 \- 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 

 s y m p t o m s : The expiration js prolonged and is attended 

 with pronounced movement of the abdominal wall (pui)ipiiig 

 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- 

 ing. The back is elevated at expiration and sinks during 

 inspiration. At the moment of expiration the anus is greatlv 

 protruded. When the abdomen is well filled, these symp- 

 toms appear more prominentl\-. 



Expiratory dyspnea occurs : 



1. In vesicular and interstitial emphysema. 



2. In chronic bronchitis and peri-bronchitis. 



3. Where the lung has adhered to the costal wall. 



A mixed dyspnea is present when accelerated 



