172 DISEASES OF THE PARENCHYMA OF THE LUM*. 



greater frequence in children. The length of each respiration is piopor- 

 tionately short, the breathing is superficial, a fresh inspiration is required 

 during the enunciation of even a short sentence, speech is interrupted. 

 As the act of inspiration is executed rapidly, and with a certain degree 

 of caution and anxiety, the levatores alae nasi are contracted with every 

 breath, and the alae nasi dilated, causing the nostrils to " work." The 

 shortness of breath is due, 1st, to the slowness with which blood is 

 renovated in the inflamed part of the lung ; 2d, to the diminution of 

 breathing-surface, by exudation into the air-vesicles and consequent ex- 

 clusion of air ; 3d, to collateral oedema in the uninflamed part of the 

 lung, which causes swelling of the vesicular walls and decrease in then- 

 capacity ; 4th, to the pain which a deep breath causes to the patient, 

 who therefore does not breathe deeply ; 5th, and above all else, to the 

 increased need of air, since, in the augmented combustion and accelerated 

 destructive assimilation which goes on during fever, more oxygen is con- 

 sumed and more carbonic acid is given out in the organism. We shall 

 presently see that, with the abatement of the fever, the dyspnoea ceases 

 almost completely, although all the obstacles to respiration still continue. 



Pain is so constant a symptom in pneumonia as to be absent in but 

 few instances. In most cases, but not in all, the patients assign the seat 

 of the pain to the point at which the inflamed lung comes in contact 

 with the thorax. In other cases it is felt at more remote points, and 

 even on the other side. It is, therefore, a doubtful matter, at least, 

 whether the pneumonic " stitch " is solely due to participation of the 

 pleura in the inflammation. Every deep inspiration, and especially 

 every forcible expiration, such as accompanies coughing or sneezing, 

 aggravates the suffering, as do also pressure upon the thorax and move- 

 ment of the intercostal muscles. The character of the pain is usually 

 described by the patient as piercing or stabbing. Its intensity varies. 

 It rarely continues in all its violence for any length of time. It is one 

 of the most burdensome symptoms at the commencement of the disease, 

 and afterward diminishes or completely ceases. It is apt to be of an 

 exceedingly transitory character, or even to be altogether wanting in 

 the pneumonia of old persons and very feeble subjects, particularly if the 

 seat of the inflammation be the apex of the lung or one of the upper 

 lobes. It is of importance to be aware of these facts. 



Cough very soon associates itself with the fever, dyspnosa, and pain 

 in the side. It is hardly ever absent, excepting in the cases above 

 alluded to, the pneumonia of old men, etc. It is at first short, ringing, 

 and harsh. The patients endeavor to repress it ; they dread to cough, 

 make painful distortions of the countenance while so doing, so that 

 observation of the manner of a child, while coughing, furnishes ground 

 for a distinction between bronchitis and pneumonia. In almost all 



