Pneumonia

Original Editor - The Open Physio project.

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Introduction

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". The lungs consist of bronchi, which divide into bronchioles that end in alveoli. The small blood vessels in the lungs are responsible for gaseous exchange (oxygen moving into the lungs and carbon dioxide moving out of the lungs). During a Pneumonia infection, the alveoli of one or both lungs fill up with pus or fluid. This increases the labor of breathing, and thus gaseous exchange cannot occur as it normally would

Prevalence of Pneumonia

According to UNICEF/WHO (2006) Pneumonia kills more children than any other illness -- more than AIDS, malaria and measles combined and it accounts for nearly one in five child deaths globally. It has been found that 1,6 million people die from pneumonia world wide each year. It should also be noted that pneumonia is one of the leading causes of deaths for children under the age of 5.

In South-East Asia, in the Pacific, and in Sub-Saharan Africa about 433 million young children contract the disease annually. Amongst children under the age of 5, these two regions have the highest incidence of pneumonia cases and when combined, they "bear the burden of more than half the total number of pneumonia episodes worldwide". Pneumonia accounts for approximately 5% of deaths in Ireland.

Types of Pneumonia

• Aspiration 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
  • Aspiration of large amounts of gastric contents can cause acute respiratory distress within 1 hour
  • Immediate physiotherapy is required to help with secretion clearance

• 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
  • Most common type of pneumonia
  • This means the infection was acquired at home in a person who has not recently been hospitalised
  • With this type of pneumonia the most common cause is 'Streptococcus Pneumonia'

• Hospital-acquired Pneumonia
  • Patients develop features during or after hospitalisation for another illness or procedure with a latency period of 72 hours
  • Infectious agent is often Gram-negative bacteria such as 'Escherichia coli or Klebsiella'
  • 5% of patients are reported to develop hospital-acquired pneumonia

• 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.

Stages of Pneumonia

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

• 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
• 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"

• 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"

• Resolution
  • This 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"

Causes

There are many different causes of pneumonia which can be classified as infective or aspiration pneumonia.

Infective pneumonia:

• the infection and inflammatory response of the lungs and bronchial tubes when bacteria or a virus enters the lung and proliferates
• can occur through inhaling small droplets containing pneumonia
• causing organisms such as Streptococcus pneumoniae.

Aspiration pneumonia:

• caused by inhaling vomit, mucous, bodily fluids, or certain chemicals
• causing the lungs and bronchial tubes to become inflamed

Risk factors

The elderly, infants and young children are more at risk of contracting community-acquired pneumonia than young and middle-aged adults. Underlying health problems such as:

• Flu
• Cancer
• Age >65years
• Smoking
• AIDS
• heart disease
• Diabetes
• Asthma
• chronic bronchitis
• Emphysema
• Chronic obstructive pulmonary disease
• Bronchiectasis
• Immunosuppressive disorders and therapy
• Debility or stroke
• Coma
• Problems with swallowing
• Alcoholism
• Intravenous drug abuse

Cause a person's immune system to be weakened - thus leaving them at risk of contracting Pneumonia. It has also been found that frequent exposure to cigarette smoke increases the risk of developing Pneumonia (Health24.com)

Signs and symptoms

Initially symptoms are similar to that of a cold followed by:

• A high fever (pyrexia)
• Chills
• Productive cough

Sputum may be discoloured and may become blood-stained as the pneumonia progresses. The following may also occur:

• Dyspnoea
• Sharp chest pain
• Worsening cough
• Fever/chills
• Tachycardia
• Pleuritic chest pain
• 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

Chest X-rays often lag behind the clinical presentation.The X-ray will show decreased lung expansion and patchy opacity on the affected side with ill defined margins

Diagnosis

• Physical examination
  • Auscultation- Bronchial breath sounds or fine cracks over the affected area
  • ? Pleural rub
• Chest X-ray
  • usually done to confirm the diagnosis
• Sputum samples and blood tests
  • done to diagnose the type of pneumonia that is present
  • sputum test is done to determine whether it is a fungal or bacterial infection
  • blood test is done to examine the White Blood Cell count of the involved patient
  • this can be used to indicate the severity of the pneumonia, as well as to determine whether it is a viral or bacterial infection.
  • bacterial infection would result in a blood count that has an increased amount of neutrophils
  • a blood count that has an increased amount of lymphocytes would indicate a viral infection.
  • Increased CRP

Complications

• Pleural effusion
  • When fluid accumulates between the pleura and the chest wall due to the large amount of fluid already present in the lungs.
  • As a result of the Pneumonia, a pleural effusion may develop which could lead to the collapse of the lungs if not treated appropriately
• Empyema
  • Pus may be present in the lungs due to the infection.
  • Thus pockets of pus may develop in the cavity between the pleura and the chest wall, or in the lung itself which is otherwise known as empyema
• Lung abscess
  • A lung abscess develops when the infection has destroyed lung tissue and a cavity filled with pus is formed
• Bacteremia
  • This occurs when the infection is no longer contained within the lungs and moves into the bloodstream, thus the blood is infected
• Septicemia
  • When bacteremia occurs septicemia can follow, as this is an infection that is spread throughout the body.
  • The infected blood is the best way for the infection to manifest in other parts of the body (Health-cares.net, 2005).
• Meningitis
  • The infection may spread to the meninges that cover the brain and spinal cord, leading to meningitis
• Septic arthritis
  • When bacteremia has occurred septic arthritis is also a danger, as the bacteria manifests in the joints through which blood passes
• Endocarditis or pericarditis
  • As blood is also circulated through the heart muscles and the pericardium, the risk of developing an infection there is very high if bacteremia is present

Treatment

Treatment will vary depending on how bad the symptoms are, and what the cause of the infection is.

• Bacterial Pneumonia can be treated with penicillin and/or anti-biotics

• Viral Pneumonia cannot be treated with anti-biotics, as they have no effect. This type of pneumonia normally resolves over time.

• Mycoplasma Pneumonia is usually treated with anti-biotics.

Doctors will also include the following when treating patients with pneumonia:

• Breathing exercises
• Analgesic administration
• Cough suppressant medication
• Fever-reducing medication (i.e.: Aspirin)
• Oxygen therapy (when indicated)

Physiotherapy Management

• Modified postural drainage - this allows gravity to drain secretions from specific segments of the lungs
• Shaking and vibes - 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

A state-of-art review suggests avoiding repeated airway clearance in infants and children with acute pulmonary disease. The treatment should be based on patient assessment and presentation of symptoms.

Clinical Guidelines for Physiotherapy management of Community-Acquired Pneumonia

For Patients admitted to hospital;

• CPAP should be considered for patients with type 1 respiratory failure who remain hypoxaemic despite optimum medical therapy and oxygen. (Grade C)
• NIV can be considered for selected patients with type II respiratory failure, especially those with underlying COPD. (Grade C)
• Medical conditions permitting, patients should;
  • Sit out of bed for at least 20mins within the first 24hours
  • Increase mobility each subsequent day of hospitalisation (Grade B)
• The regular use of PEP should be considered (Grade B)
• Patients should NOT be treated with traditional airway clearance, +/- IPPB routinely. (Grade B_

Children and Pneumonia

Why are children vulnerable?

• Unlike healthy children with many natural defenses to protect them against the invasion of pathogens in the lungs, the unhealthy children with a compromised immune system has weak defenses.
• Children who suffer from malnutrion, particularly inadequate zinc intake and lack of exclusive breastfeeding have a higher risk of developing pneumonia.
• Other risk factors include:
  • Being born premature
  • Having asthma or genetic disorder such as sickle-cell disease
  • Having heart defects such as ventricular septal defect (VSD), atrial septal defect (ASD) or patent ductus arteriosus (PDA)
• Several environmental factors such as overcrowding homes and exposure to parental smoke increases a child's susceptibility to pneumonia and its complications.

Signs & Symptoms in children

• In children the signs and symptoms are similar to that of adults.
• Sometimes a child's only sign may be rapid breathing and often when pneumonia exist in the lower part of the lungs, no breathing problems may be present but rather fever, abdominal pain or vomiting.
• If pneumonia is caused by bacteria, the infected child becomes sick relative quickly and is prone to developing high fever and rapid breathing.
• If pneumonia is caused by viruses, symptoms may appear gradually and less severe than the bacterial pneumonia.
• Parents should be aware of the following signs and symptoms:
  • Nostril flaring
  • Sternal retraction
  • Increased breath rate
    • > 60 breaths/min for newborns up to 2 months
    • > 50 breaths/min for 2 months to 12 months
    • > 40 breaths/min for a child older than 1 years of age

Prevention

• Vaccines are usually administered to prevent infection by viruses and bacteria.
• Kids usually receive routine immunisation against Haemophilus Influenzae and Pertussis at the age of 2 months of age.
• Some vaccines are also administered against pneumococcus organism, a common cause of pneumonia

Transmission of pneumonia - Infection may occur in different ways may it be through contaminated air droplets, blood-born infection or from coming into contact with contaminated substances during delivery. Either way it is believed that babies already have the bacterial pathogens causing pneumonia in their nose and/ or throat and are inhaled into the lungs.