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PNEUMONIA

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Pneumonia is defined as "inflammation of the lung caused by bacteria, in which the air sacs (alveoli) become filled with inflammatory cells and the lungs become solid.

Pneumonia is "a severe form of acute lower respiratory infection that specifically affects the lungs". During a Pneumonia infection, the alveoli of one or both lungs fill up with pus or fluid. This increases the work of breathing, and thus gaseous exchange cannot occur as it normally would.

Types of PneumoniaAspiration Pneumonia Aspiration Pneumonia results when food, drink, vomit, secretions or other foreign material is inhaled and causes an inflammatory response in the lungs and bronchial tubes.

Aspiration Pneumonia occurs predominantly in the right lung because its total capacity is greater than that of the left lung.

Atypical Pneumonia This term refers of Pneumonia caused by the following bacteria: Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydophila pneumoniae.

Atypical pneumonia is caused by bacteria and does not respond to the normal antibiotics used for treatment.

Bacterial Pneumonia Bacterial Pneumonia occurs when pneumonia-causing bacteria masses and multiplies in the lungs. The alveoli become inflamed and pus is produced, which spreads around the lungs. The bacteria that caused Bacterial Pneumonia are: streptococcus pneumonia, hemophilus influenza, legionella pneumophilia and staphylococcus aureus.

Bronchial Pneumonia Bronchopneumonia is a descending infection starting around the bronchi and bronchioles.

The terminal bronchioles become blocked with exudates and form consolidated patches. This results in atelectasis.

Community-acquired Pneumonia This means the infection was acquired at home.

With this type of pneumonia the most common cause is 'Streptococcus Pneumonia.

Hospital-acquired Pneumonia Patients develop features after being in hospital for 24 hours or longer

Infectious agent is often Gram-negative bacteria such as 'Escherichia coli or Klebsiella.

Mycoplasmal Pneumonia (also known as 'walking pneumonia') It is similar to bacterial pneumonia, whereby the mycoplasmas proliferate and spread - causing infection.

Pneumocystis carinii Pneumonia Pneumocystis carinii pneumonia is the result of a fungal infection in the lungs caused by the Pneumocystis carinii fungus.

This fungus does not cause illness in healthy individuals, but rather in those with a weakened immune system.

Ventilator Associated Pneumonia (VAP) This type of pneumonia usually occurs two days after a hospitalised patient has been intubated and been receiving mechanical ventilation.

This is especially a life-threatening infection as patients who require mechanical support are already critically ill.

Viral Pneumonia Viral Pneumonia is believed to be the cause of half of all pneumonias. The viruses invade the lungs and then multiply- causing inflammation.

Risk factorsflu cancer AIDS heart disease diabetes asthma chronic bronchitis emphysema chronic obstructive pulmonary disease brochiectasis immunosuppressive disorders and therapy debility or stroke coma problems with swallowing alcoholism intravenous drug abuse

Risk factorsThe elderly, infants and young children are more at risk of contracting community-acquired pneumonia than young and middle-aged adults.

Frequent exposure to cigarette smoke increases the risk of developing Pneumonia.

Stages of Pneumonia Pneumonia has four stages, namely consolidation, red hepatization, grey hepatization resolution.

Stage of Consolidation Occurs in the first 24 hours Cellular exudates containing neutrophils, lymphocytes and fibrin replaces the alveolar air Capillaries in the surrounding alveolar walls become congested The infections spreads to the hilum and pleura fairly rapidly Pleurisy occurs Marked by coughing and deep breathing

Stage of Red Hepatization Occurs in the 2-3 days after consolidation At this point the consistency of the lungs resembles that of the liver The lungs become hypeaemic Alveolar capillaries are engorged with blood Fibrinous exudates fill the alveoli This stage is "characterized by the presence of many erythrocytes, neutrophils, desquamated epithelial cells, and fibrin within the alveoli.

Stage of Grey Hepatization Occurs in the 2-3 days after Red Hepatization This is an avascular stage The lung appears "gray-brown to yellow because of fibrinopurulent exudates, disintegration of red cells, and hemosiderin" The pressure of the exudates in the alveoli causes compression of the capillaries "Leukocytes migrate into the congested alveoli"

Stage of ResolutionThis stage is characterized by the "resorption and restoration of the pulmonary architecture" A large number of macrophages enter the alveolar spaces Phagocytosis of the bacteria-laden leucocytes occurs "Consolidation tissue re-aerates and the fluid infiltrate causes sputum" "Fibrinous inflammation may extend to and across the pleural space, causing a rub heard by auscultation, and it may lead to resolution or to organization and pleural adhesions"

SEGMENTS AFFECTED FROM PNEUMONIABRONCHIAL PNEUMONIA it involves the terminal bronchial and alveoli.LOBAR PNEUMONIA It involves one or more entire lobes.SEGMENTAL PNEUMONIA It involves the a segment of lobes.BILATERAL PNEUMONIA It affects the lobes in both lungs.INTERSTITIAL PNEUMONIA It is also called reticular pneumonia. It involves inflammatory response within the lung tissues surrounding the airspaces.

f) ALVEOLAR PNEUMONIA It is also acinar pneumonia. There is fluid accumulation in a lung distal air spaces.

g) NECROTIZING PNEUMONIA : it causes the death of a portion of lung tissues. X ray examination reveal cavity at the formation at the site of necrosis. Necrotic lung tissue ,which does not heal constitutes a permanent loss of functioning parenchyma.

SIGNS AND SYMPTOMS Initially symptoms are similar to that of a cold followed by: a high fever (pyrexia) chills a productive cough Sputum may be discoloured and may become blood-stained as the pneumonia progresses.

SIGNS AND SYMPTOMS dyspnoea sharp chest pain worsening cough headaches malaise muscle pains cyanosis due to poorly oxygenated blood loss of appetite rapid breathing wheezing or grunting during breathing intercostal muscle recession during breathing vomiting

DIAGNOSIS Physical examination crackles and wheezing may be heard while auscultating Chest X-ray usually done to confirm the diagnosis. The X-ray will show decreased lung expansion and opacity on the affected side.Sputum samples and blood tests

MEDICAL MANAGEMENT Bacterial Pneumonia can be treated with penicillin and/or antibiotics Viral Pneumonia cannot be treated with antibiotics, as they have no effect. This type of pneumonia normally resolves over time. Mycoplasma Pneumonia is usually treated with antifungals.

MEDICAL MANAGEMENT Bed rest Breathing exercises Analgesic administration Cough suppressant medication Antipyretics Oxygen therapy (when indicated)

Physiotherapy Management Modified postural drainage - this allows gravity to drain secretions from specific segments of the lungs Vibration - to mobilize secretions Coughing and huffing exercises - to expectorate secretions Administer humidification - to mobilize secretions Breathing exercises - Localized and Diaphragmatic IPPB administration - to increase lung volumes Mobilization of the patient - done to increase air entry, increase chest expansion, and to loosen secretions

COMPLICATIONS Pleural effusion Empyema Lung abscess Bacteremia Septicemia Meningitis Septic arthritis Endocarditis or pericarditis