Respiratory conditions Flashcards
What is pneumonia?
-lung inflammation caused by infection
-it typically affects the lower airway and causes the development of secretions which build up and block the airways
-this can create consolidation and cause the lung to collapse
What are the signs and symptoms of pneumonia?
-malaise/ confusion
-fever
-chills
-rigor
-tachycardia
-tachypnoea/ dyspnea
-cough
-vomiting
-diarrhoea
What are the causative agents of pneumonia?
-bacteria e.g strep, hemophilus influenza
-viruses e.g influenza, respiratory cidiil virus
-fungi aren’t common, only higher risk in immunocompromised
-they enter and infect the respiratory through inhalation, it enters the alveoli and initiates an immune response
What are the (6) different types of pneumonia?
-lobam pneumonia= consolidation of one lobe
-broncho pneumonia=
affects patches throughout respiratory tract
-community acquired pneumonia= often bacterial or viral
-Nosocomial (hospital acquired)= not incubating at time of admission and develops in a patient hospitalised for longer then 48 hours
-aspiration pneumonia= when patient vomits they can aspirate stomach content with gut bacteria
-chronic pneumonia= usually involves fungal causative agents so more common in immunocompromised patients
How is pneumonia managed and treated?
-oxygen
-IV fluids
-pain management
-use of antibiotics, if non complicated oral will be used, but if complicated may be IV
What is bronchiolitis?
Inflammation of the bronchioles which involves narrowing of the airways due to mucous hyper secretion, cell wall thickening, and smooth muscle contraction, most commonly seen in neonates and under 2s
What is the main causative agent for bronchiolitis?
Respiratory Syncytial Virus (RSV), a single stranded RNA virus that is spread through airborne droplets or direct contact with respiratory secretions
What are the signs and symptoms of mild/ moderate bronchiolitis compared to severe bronchiolitis- how is this managed?
Mild/ moderate:
-fever
-increased work of breathing
-nasal flaring
-tracheal tug
-intercostal recessions
-wheezing
-abdominal breathing
Severe:
-infants appear very unwell
-very high or very low respiratory rate
-apnea (stop breathing)
-grunting
-cyanosis
-paleness
-difficulty feeding
-largely supportive focusing on maintaining oxygenation and hydration of the patient
What actually happens to the respiratory tract in bronchiolitis?
-bronchioles, leading to the bronchi become inflamed
-the inflammatory process responds to the damage caused by the epithelial layer in the airways triggering the release of tissue mediators which activate the eosinophils, neutrophils and monocytes
-submucosa swells causing debris and fibrin to form plugs in the bronchioles
-bronchospasm can also occur
-secretions are produced which block the small airways and prevent oxygen getting to the alveoli and body, =hypoxia, co2 also is not excreted
-the volume of secretions can result in the airway becoming blocked, causing air trapping, where oxygen can be inhaled but gets trapped in the lower respiratory tract in the alveolus to surrounding inflammation, causing difficulty in breathing
-this produces a ventilation-perfusion mismatch
How does the body respond to a covid-19 infection both in the lungs and in the bloodstream?
-in the lungs the reaction appears similar to a severe pneumonia where tissue mediators create inflammation and release cytokines
-once the virus enters the blood stream then the response is typical of the response seen in sepsis as the body releases tissue mediators to fight the infection.
How and why might covid-19 affect people differently?
There is a hypothesis that the virus may be attacking the T cells trying to recognise it and kills them before a response can be initiated
The elderly are also more at risk due to a reduced immune response and ability for the lung epithelium to repair its-self.
Children are generally less affected as they have a thymus gland which supports the development and maturing of T cells
What is asthma?
-defined as a chronic inflammation disorder of the airways
-having airway inflammation which narrows the airway causing obstruction to airways and resulting in a hyper-responsive airway
What is atopic asthma?
-the most common type
-extrinsic meaning triggered by the environment
-this involves inflammation mediated by systemic IgE production
What is non-atopic asthma?
-not common
-intrinsic meaning inflammation and constriction of airways that is not caused by exposure to allergen
-the inflammation is mediated by local IgE production
What are some of the differences between a normal bronchi and an asthmatic bronchi?
Asthmatic bronchi:
-lumen is much narrower
-increased mucous production and goblet cells
-more mast cells= more histamine
-more neutrophils and T helper cells
What are the risk factors for asthma?
-air pollution
-tobacco smoke
-respiratory tract viral infections
-oesophageal reflux
-obesity
-decrease in exposure to certain microorganisms (immunological imbalance)
What is the pathophysiology of an early asthmatic response?
-antigen exposure to the bronchial mucosa, activates dendritic cells, T cells respond releasing cytokines
-this stimulates the production of B cells and antigen specific IgE.
-activation of the eosinophils= causes tissue injury and releases toxic neuropeptides
-neutrophils are activated= reduces ability to clear secretions and supports constriction of smooth muscle to narrow the airway
-inflammatory response increases as IgE causes mast cells to release more tissue mediators= tigger capillary permeability, vasodilation, mucosal oedema, bronchospasm and sticky secretions
What is the pathophysiology of a delayed asthmatic response?
-late release of more tissue mediators= creates more tissue damage and increased secretions that can plug the airway
-increase in synthesising nitric oxide creates oxidative injury and chronic inflammation= creates oxidative injury and chronic inflammation
-untreated inflammation can lead to the airway remodelling which is irreversible= can lead to the airway remodelling which is irreversible
Explain how asthma is seen as being type 1 hypersensitivity to the IgE
-Type 1= reactions in response to environmental allergens
-IgE is produced and the person becomes sensitised to the level of IgE
-IgE attaches to mast cell triggering inflammatory response
In asthma histamine:
-contracts smooth muscle narrowing the airways
-dilates blood vessels
-attracts eosinophils into the area
What are the other physiological reactions in as asthma attack?
-expiratory wheeze
-use of accessory muscles
-feeling tight
-breathless and tachypnoea
-hypoxia and hypoxaemia
-tachycardia
-non productive cough
What are the major physiological reactions that happens in an asthma attack?
-airway obstruction= increased resistance
-inability to exhale= air trapping and increase WOB
-intrapleural and alveolar gas pressure increases= V:Q mismatch = hypoxic
-Hypoxia stimulates respiratory centre= CO2 levels fall
What are the severe physiological reactions that happens in an asthma attack?
-severe hyper-expansion and an inability to adequately move muscles in the chest, putting pressure on the heart, compromising cardiac output
-bronchospasm
-using accessory muscles wheezing on both inspiration and expiration
What medications are used to treat asthma?
-supplemental oxygen
Nebulisers:
-bronchodilators e.g salbutamol B2 agonist
-anticholinergic if response to salbutamol is poor
Steroids:
-moderate asthma= oral prednisolone
-severe asthma= IV hydrocortisone
If these don’t work IV magnesium or IV aminophylline
What long term asthmatic medications can be used?
-short acting B adrenergic agonists
-anticholinergic medicine
-systemic corticosteroids
-anti-inflammatory agents
What is cystic fibrosis?
-a recessive genetic condition
-the gene that is responsible for making a protein which regulates the amount of chloride and sodium going in and out of the cell is faulty. This makes the mucus that lines the airways and other organs thick and sticky and therefore less able to clear secretions and protect against infection
What are the signs and symptoms of cystic fibrosis?
coughing, regular chest infections, difficulty absorbing fat which results in poor weight gain
How can cystic fibrosis be controlled/ managed?
-a combination of medication and physiotherapy can help control lung infections and prevent lung damage
-medications may include antibiotics to help treat or control chest infections, medicines to help clear mucous from the lungs, and steroids or bronchiodilators
How is cystic fibrosis diagnosed?
Apart of routine screening in newborn babies from a heel prick blood sample at a few days old
What is croup?
Croup is a common condition that mainly affects babies and young children airways, caused by a virus
What are the symptoms of croup?
-a barking cough
-a hoarse voice
-difficulty breathing
-high pitched rasping sound when breathing in
-and other normal cold symptoms like a temperature and runny nose
-croup symptoms usually worsen over night and improve during the day
What is the treatment for croup?
-croup is caused by a virus therefore it cannot be treated with antibiotics
-some children may require steroids to reduce swelling and inflammation in their throats
What is a pneumothorax?
-An air leak in the lungs when air from the lungs leaks into the chest area
-often occurring 24-36 hours after birth
-how serious the illness is depends on where the leak is, how quickly it occurs and how much air is leaking
-can potentially lead to cardiac arrest or death
What are some of the potential causes of a pneumothorax?
-most common cause is air delivered by a breathing machine, a baby born with lung disease may need to be on a breathing machine
-meconium aspiration- when a baby is still in its mothers uterus and breathes in its first stool. Air may become trapped causing lungs to expand too much
-pneumothorax can also occur suddenly in children but this is uncommon
What are the symptoms of pneumothorax?
-irritability and restlessness
-rapid breathing
-grunting
-nostril flaring
-skin on the chest sinks in around the ribs when the child breathes
-pale or blue-ish skin
How can pneumothorax be diagnosed?
-chest x ray= may show air in places that is not normal, a collapsed lung, or abnormal structures
-transillumination= a fibre-optic light probe is put on the baby’s chest wall and the side of the chest with the air leak shows a brighter light. This is often used in an emergency
How can pneumothorax be treated?
-giving extra oxygen
-removing collected air using a syringe and catheter
