What are the different zones of the lungs?
Zone 1, where alveolar pressure is higher than arterial or venous pressure; Zone 2, where the arterial pressure is higher than alveolar and venous, a relationship which changes during the respiratory cycle. Zone 3, where both arterial and venous pressure is higher than alveolar.
Why are West zones important?
Zones of Lung An understanding of the west zones of the lung is essential to comprehend both lung perfusion and ventilation. West zones describe areas of the lung based upon variations in pulmonary arterial pressure (PAP), pulmonary venous pressure (PVP), and alveolar pressure (AP).
What are dependent lung zones?
The lowest part of the lung in relation to gravity is called the dependent region. In the dependent region smaller alveolar volumes mean the alveoli are more compliant (more distensible) and so capable of more oxygen exchange.
Which zone of lung has highest ventilation?
The ventilation/perfusion ratio (V/Q ratio) is higher in zone #1 (the apex of lung) when a person is standing than it is in zone #3 (the base of lung) because perfusion is nearly absent. However, ventilation and perfusion are highest in base of the lung, resulting in a comparatively lower V/Q ratio.
How do lungs divide into zones?
retrodiaphragmatic: behind the hemidiaphragms bilaterally….Hence, describing the location of pathology using the four-zone technique is helpful:
- apical zone: above the clavicles.
- upper zone: below the clavicles and above the cardiac silhouette.
- mid zone: the level of the hilar structures.
- lower zone: the lung bases.
Where is the respiratory zone?
respiratory zone is found deep inside the lungs and is made up of the respiratory bronchioles, alveolar ducts, and alveoli. These thin-walled structures allow inhaled oxygen (O2) to diffuse into the lung capillaries in exchange for carbon dioxide (CO2).
What zone has the waterfall effect?
Respirology 1996; 1: 5-9 Abstract The concept of the waterfall phenomenon in Zone 2 in the pulmonary vasculature is well known from West’s lung model.
Why in Zone 1 of the lungs there is no blood flow?
Zone 1 is defined as those areas of the lung where alveolar pressure exceeds that of the pulmonary arterial pressure. Consequently, the pulmonary arteries become compressed and shut, eliminating blood flow in this zone and thus creating a zone of dead space.
What are dependent lung changes?
Gravity-dependent atelectasis refers to a form of lung atelectasis which occurs in the dependent portions of the lungs due to a combination of reduced alveolar volume and increased perfusion. Being due to gravity, it usually has a dependent and subpleural distribution.
What is dependent vs nondependent lung?
In the lateral decubitus position the dependent lung is under ventilated as it is compressed by the compression of the abdominal contents and the weight of the mediastinum. The nondependent lung is relatively over ventilated secondary to increased compliance as the corresponding hemithorax is opened.
Which is more alveolar ventilation or pulmonary ventilation?
Pulmonary ventilation is less than alveolar ventilation.
What is lower zone?
The lower zone is one of the four chest radiograph zones and is sometimes used synonymously with lung bases.
Where are the pulmonary segments of the lung located?
BRONCHO PULMONARY SEGMENTS 1)These are well defined sectors of the lung each one of which is aerated by a tertiary or segmental bronchus 2)Each segment is pyramidal in shape with its apex directed towards the root of the lung 3)These bronchopulmonary segments are independent respiratory units 14.
Which is the tongue shaped projection of the left lung?
8. 4)The tongue shaped projection of the left lung below the cardiac notch is called lingula.
Which is more infected in the apical zone of the lungs?
13. Apical Zone of lungs : It is more infected by Pulmonary Tuberculosis Reasons: i) There is low perfusion. ii) There is higher V/Q , higher PO2 and lower PCO2 (M.tubercle is strict aerobes) iii) Less of the oxygen is carried away by the blood in apex of lungs.
Where is the anterior border of the lung?
ANTERIOR BORDER – 1. Corresponds to the anterior (Costomediastinal) line of pleural reflection. 2. It is deeply notched in the left lung posterior to 5thcostal cartilage by the pericardium costal cartilage by the pericardium and extends vertically downwards to form