Pathophysiology Flashcards
What is pneumonia?
An inflammatory condition of the lung leading to abnormal alveolar filling with consolidation & exudation
Who does pneumonia affect?
Affects youngest and oldest most
Single largest infectious cause for death in children
What is the pathology of pneumonia?
An infection, chemical or aspiration irritant
During pulmonary infection, acute inflammation results in the migration of neutrophils out of capillaries into airspaces (alveoli), these cells phagocytose & release antimicrobial enzymes & inhibitors -> more inflammation and oedema
What are the 4 stages of pneumonia?
Congestion
Red hepatisation
Grey hepatisation
Resolution
What is the congestion stage of pneumonia?
The first 24 hours
Characterised by vascular engorgement, intra-alveolar fluid & numerous bacteria
The lung is heavy, boggy and red
What is the red hepatisation stage of pneumonia?
2-3 days
Massive exudation develops, with red blood cells, leukocytes & fibrin filling the alveolar spaces
The affected area appears red, firm & airless, with a liver like consistency
What is the grey hepatisation stage of pneumonia?
4-6 days
Progressive disintegration of red blood cells and the persistence of a fibrin exudate
What is the resolution stage of pneumonia?
> 6 days
The consolidated exudate within the alveolar spaces undergoes progressive digestion to produce debris that is later reabsorbed, ingested by macrophages or coughed up
What are the causes of pneumonia?
Bacteria Fungi Virus Parasites Chemical Aspiration Inhalation
What are the classifications of pneumonia?
Community Acquired Pneumonia (CAP)
Health Care Associated Pneumonia (HCAP)
Hospital Acquired Pneumonia (HAP)
Ventilator Associated Pneumonia (VAP)
What are the causes of CAP?
Strep pneumonia/staphylococcus aureus 25% Virus 10% Mycoplasma 6% H influenza 5% Legionella 3% Unknown cause 37%
What are the causes of HAP
MRSA 15% Pseudomonas Aeruginosa 14% MSSA 9% Kiebsiella pneumonia 3% Other gram negative rods 9% Unknown cause 37%
Common symptoms of pneumonia
Fever Malaise Muscle ache/fatigue Coughing (productive & non-productive) Tactile fremitus on palpation Dyspnoea Pleuritic or chest pain Loss of appetite Rapid heartbeat
Less common symptoms of pneumonia
Coughing up blood Fatigue Nausea/vomiting Diarrhoea Wheezing Confusion
What are the complications of pneumonia?
Lung abscess
Pleural effusions
Empyema (infection/puss inbetween pleural cavity)
Septic shock
What is the medical diagnosis for pneumonia?
Temperature> 37.8 degrees HR > 100bpm Crackles Decreased breath sounds or bronchial breath sounds Absence of asthma
What is the clinical prediction rate of pneumonia?
5 findings = 84-91% 4 findings = 58-85% 3 findings = 35-51% 2 findings = 14-24% 1 finding = 5-9% 0 findings = 2-3% With a chest x ray
What are the other diagnostic tests for pneumonia?
CXR CT scan Blood test Sputum culture Pleural fluid culture Bronchoscopy
What is the general management for pneumonia?
Antibiotics/Anti-fungal medication Oxygen support Hydration - IV fluids Rest Analgesics Cough-suppressant medication Fever-reducing medication Prevention through vaccination programmes
What is the physiotherapist treatment for pneumonia?
Care needed as may increase oxygen consumption and demand or cause a bronchospasm
Treat the clinical signs and symptoms
Non-productive - positioning V/Q, mobilising or no intervention
Productive - sputum clearance techniques including positioning, breathing exercises, adjuncts etc
What is bronchiectasis?
Permanent abnormal dilation in one or more of the lungs Bronchi
Extra mucus is secreted and pools in the areas of the airways that are dilated making the person more prone to infection
It has similar symptoms to COPD but doesn’t always show as airflow obstruction
What is the epidemiology of bronchiectasis?
Precise incidence is uncertain
Female > male
Average age of 66
What is the pathology of bronchiectasis?
Impaired mucociliary clearance leads to accumulation of secretions
Accumulation of secretions leads to infection by bacteria
Infection by bacteria leads to increased mucus production, increased impaired ciliary performance, increased inflammatory response
Excessive inflammatory response causes tissue damage
Tissue damage eventually produces dilated bronchi including loss of cilliated epithelium and impaired mucocillary clearance
VISCOUS CYCLE
What are the causes of bronchiectasis?
Idiopathic Infection (usually in childhood) Cystic fibrosis Immunodeficiency Cillary dysfunction Allergic brochopulmonary aspergillosis (ABPA) Inflammatory conditions Aspiration/obstruction
What are the clinical features of bronchiectasis?
Virtually all patients have cough & sputum production
75% dyspnoea & wheeze
50% chest pain
1/3 have signs of chronic sinusitis & nasal polyps
Recurrent exacerbations are common
Approx. 50% patients experience experience haemoptysis (very rarely life threatening)
What is the diagnosis of bronchiectasis?
Chest X-ray
High resolution computed tomography (HRCT)
Bloods & sputum microbiology
Pulmonary function tests
What are the types of bronchiectasis?
Saccular - occurs in large bronchi that become large and balloon like
Cylindrical - involves medium sized bronchi which usually are symmetrically dilated
Varicose - constrictions and dilations deform the bronchi
They can be localised or widespread
What are the symptoms of acute exacerbation?
Change in sputum production Increased dyspnoea Increased cough Temperature > 38 degrees Increased wheezing Malaise, fatigue, lethargy or decreased exercise tolerance Reduced pulmonary function X-ray changes consistent with a new pulmonary process Changes in chest sounds
What is the treatment and management for bronchiectasis?
Physiotherapy IV/oral/rebulised antibiotics Bronchodilators Steroids Nasal sprays All & pneumococcal vaccinations Surgery
What is the prognosis of bronchiectasis?
Prognosis for hospital treated patients is better than COPD but poorer than asthma
Associated disease has an effect on prognosis
What is COPD?
Characterised by airflow obstruction
- progressive in severity
- not fully reversible
- doesn’t change markedly over several months
- umbrella term for chronic bronchitis, emphysema and chronic asthma
What are the three diseases under COPD?
Emphysema
Chronic bronchitis
Asthma
What is normal airway clearance?
Airways are lined with cells which produce mucus and tiny hairs (cilia) which continually beat
Mucus traps dust particles and bacteria
The cilia move the mucus along until it reaches the throat and we swallow it or cough
Defence mechanism
What can go wrong in airway clearance in COPD?
Excess mucus is produced Mucus is thicker and stickier The cilia are unable to beat Smoking paralyses the cilia This means: - dust and bacteria stay trapped in the airways - mucus build up & provides warm, moist environment for bacteria to grow - infections can develop
What is bronchitis?
Chronic disease of the lungs where bronchi become inflamed
The inflammation causes more mucus to be produced which narrows the airways & makes breathing more difficult
What does bronchitis cause?
Increased sputum production - over production of mucus in airways which becomes difficult to clear
Wheezing is very common (especially after coughing) due to inflamed airways narrowing for short periods of time which reduces the amount of air entering the lungs
Inflamed airways
Airways narrower with less space for sputum to get through
May feel tired, unwell and unable to cough
What’s emphysema?
A condition where the alveoli of the lungs become inflamed and lose their natural elasticity
The alveoli over expand and lose their ability to fill up and contract properly
As air fills up in these sacs some rupture and become one sac reducing surface area for gas exchange
When breathe out the trapped air cannot be released and breathing becomes more and more difficult
What’s asthma?
An episodic increase in airway obstruction caused by various stimuli resulting in increased airway resisted
Common disease in UK - approx 5 million people suffer with it
Often reversible airway disease but it can become chronic with some fixed airway damage and therefore comes under COPD umbrella
Inflammation & Bronchoconstriction
What are the symptoms of asthma?
Breathlessness
Wheeze
Tightness in chest
Why are the airways sensitive in asthma?
Become irritated, inflamed and narrow
Reduced airflow through the airways
What are the causes of COPD?
Cigarette smoking (90%) significant smoking history - 20 pack years or more
Occupational exposure - coal miners
Alpha-1 Antitrypsin deficiency
Social deprivation