(2) Pathophysiology: Pneumonia is an excess of fluid in the lungs resulting from an inflammatory process. It is an acute infection of the alveoli. This is a global problem, and the WHO (World Health Organization) suggests that it is the most common cause of death in children and that 1.4 million die each year as a result of pneumonia. Pneumonia may also occur as a complication in hospital settings, secondary to surgery.
The inflammation occurs in the interstitial spaces, the alveoli, and often the bronchioles. The process begins when organisms penetrate the airway mucosa and multiply in the alveoli. WBCs migrate to the area of infection, causing local capillary leak, edema and exudate. These fluids collect in and around the alveoli, and the alveolar walls thicken. Both events seriously reduce gas exchange and lead to hypoxemia, interfering with oxygenation and possibly leading to death. The capillary leak spreads the infection to other areas of the lung. If the organisms move into the bloodstream sepsis occurs.
(3) Etiology: Pneumonia develops when the immune system cannot combat the virulence of the invading organisms. Organisms from the environment, invasive devices, equipment and supplies, staff, or other people can invade the body. Pneumonia can be caused by bacteria, viruses, fungi, protozoa. Noninfectious causes of pneumonia include inhalation of toxic gases, chemical fumes, and smoke and aspiration of water, food, fluid, and vomitus.
(4) Signs & Symptoms: Pneumonia may present with a 1-2 day history of cough, fever, dyspnea, fatigue, rigors and pleuritic pain. Cough can be dry and persistent or it may be productive. On examination the respiratory rate is likely to be rapid, crackles may be audible on inspiration and there may be evidence of pleural effusion.
(5) Diagnostic Evaluation: Some diagnostic tests that can be performed are chest X-ray, sputum test is obtained and