IV. PATHOPHYSIOLOGY

1. Schematic diagram

Book Based Pathophysiology:

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Precipitating/Modifiable factors

Environment Exposure to

Pathologic Microorganism

aspiration of foods or fluids

Lung Disease

Injury/accidents

Smoking

Non Modifiable / Predisposing Factors Age especially infants Immunocompromised Common Colds

Any Chest Injury

Pneumothorax

Allows air to enter the pleural space

Increase intrathoracic pressure and reduction in vital capacity

Penetration into the pleural space by an object external to the chest wall (such ash knife/needle)

Open Pneumothorax

Penetrating/Non penetrating injuries

Internal Mechanism (such as broken rib or bleb rupture of the lung) air or blood enters the pleural space.

Injury to the chest or respiratory structures

Closed Pneumothorax

Air filled bleb/blister on the lung surface ruptures

Manifestations:Depends on its size and the integrity of the underlying lung.

Large Pneumothorax

Hypoxemia

Vasoconstriction of the blood vessels in the affected lung.

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Fractured/dislocated ribsthat penetrates the pleura

Hemothorax

Chest Trauma

Other Complication

Medical Procedure such as intra thoracic needle aspirations, intubation, and positive pressure ventilation

Cardiopulmonary resuscitation (CPR)

Traumatic Pneumothorax

Tension Pneumothorax

Intrapleural pressure exceeds atmospheric pressure.

Rapid increase of pressure in chest with compression atelectasis of unaffected lung

Air enters the pleural space but does not leave

Spontaneous Pneumothorax

Primary SpontaneousPneumothorax

Air filled blebs rupture on TOP of the lungs.

Unknown cause Lung Disease

Catamenial Pneumothorax

Air may gain access to the peritoneal Cavity during menstruation and then enter the pleural cavity through diaphragmaticDefect.

History of endometriosis

Secondary Spontaneous Pneumothorax

Trapping of gases & Destruction of lung tissue

Shift in mediastinum to the opposite side of the chest and compression of the vena cava with impairment of venous return to the heart

Intrapleural pressure exceeds atmospheric pressure.

Manifestations: Ipsilateral chest pain Inc. in RR Dyspnea Inc. HR Asymmetry of chest Hyperresonant sound upon percussion Breath sounds decreased/absent over the

area of the pneumothorax.

Manifestations: Structures in the mediastinal space shift toward

the opposite side of the chest. Distention of neck veins Subcutaneous emphysema Clinical signs of shock

Partial/total loss of lung function

Hypoxemia

Life threatening