The Lungs & their function

1. Obstructive diseases ( Status ashmaticus, COPD )

characterized : 1) obstrction to airflow through airways,
2) prolonged expiration,
3) gas trapping
--> Hyperinflation
--> ��� The FRC & the TLC
(TLC= total lung capacity, the maximum achiavable end-inspiratory lung volume)

2. Restrictive diseases

ex : chest wall abnormalities ( e.g., scoliosis)
N-M problems (e.g., Phrenic n. injury)
Parenchymal diseases (e.g., interstitial lung disease, Pulmonary edema)
pleural effusions,
Pneumothorax,
extrathoracic problems(e.g., ��� intraabd. Pr)
--> ��� FRC, TLC
* ���媛���� FRC 痢≪�� 諛⑸����� Invasive������ ��ъ�⑺����� ���怨�
Plethymograp濡� FRC��� 蹂����瑜� 鍮���룻��寃� 痢≪����� ��� ������.
Mechanics of Ventilation
Ventilation
: Repetitive creation of pr. gradients between ambient(mouth) & alveolar pr.
--> overcome flow resistance in airways
--> gas movement in & out of the Lungs.
end expiration : alveo���(������)

1) during Inspiration : inspiratory m. expand the thoracic cavity

2) Active expansion cease : alveolar pr. quickly equalizes c ambient

3) end inspiration : inspiratory m. relax