The expansion of the lungs during inspiration follows the enlargement of the thoracic cavity in all its diameters by the contraction of the respiratory muscles. These are mentioned below: 1. Diaphragm: A dome-shaped muscle separating the abdominal wall from the thoracic cavity, with vertically running fibres at the periphery and horizontally running fibres at the centre ending in the central [...]
In this article we will discuss about the subdivisions of lungs and capacities obtained by a spirometer with the help of suitable diagrams. 1. Lung Volumes: (i) Tidal Volume (TV = 500 ml): The TV (or Resting Tidal Volume, RTV) is the volume of air breathed in and out during quiet respiration (about 500 ml). (ii) Respiratory Minute Volume (RMV): [...]
In this article we will discuss about:- 1. Definition of Respiratory Dead Space 2. Types of Respiratory Dead Space 3. Measurement. Definition of Respiratory Dead Space: The respiratory tract is so designed that during inspiration its upper part upto the level of terminal bronchiole is filled with atmospheric air. The first part of the expired air, therefore, is also atmospheric [...]