Respiratory disease Flashcards
ventilation is one of the components that is needed to get adequate oxygen supply into the blood.
ventilation requires what 2 things?
airway patency
active muscles
what is airway patency?
how wide or narrow the airways are
what does active muscles mean in regards of ventilation?
ability of the muscles to move the ribcage in order for ventilation to take place
gas exchange is one of the components that is needed to get adequate oxygen supply into the blood
what does gas exchange require?
adequate number of alveoli
no fibrosis of alveolar wall
what can be a sign that ventilation is compromised in a patient clincally?
patient is anchoring arms by holding onto the dental chair so that the accessory muscles can assist in ventilation -> shows breathing is compromised
what happens if there is Inadequate ventilation due to airway patency or muscle action problems
oxygen levels fall and carbon dioxide levels rise in the alveoli
define type 2 respiratory failure
when ventilation is inadequate to deliver enough oxygen to the blood and remove the carbon dioxide
gas exchange failure can be due to what 3 things?
fibrosis - thick walls
emphysema - less aveoli
v-q mismatch - air and blood in same part of lungs for exchange to occur
what is emphysema?
destruction of alveoli, air sacs join up to form larger spaces with less surface area -> reduce gas exchange
gas exchange failure leads to what kind of respiratory failure?
type 1 respiratory failure
Symptoms of respiratory problems
Cough
Wheeze -> expiratory noise
Stridor -> inspiratory noise
Dyspnoea -> patient feels distressed or anxious by the effort of breathing
Pain
respiratory investigations
spirometry looks at the ability to ventilate the lungs
define these
tidal volume -
inspiratory capacity -
FVC
FEV 1
PEFR
Tidal volume - normal breathing volume in and out
Inspiratory capacity - take big breath in
FVC - breathing out after taking a big breath
FEV 1 second - how much gas can be removed from the lungs in 1 second
PEFR - peak expiratory flow rate (patients can measure this at home)
Asthma is ? of the airways to seemingly innocuous stimuli, causing a change in the ?? which ? the airway, restricting the airflow in and out - typically makes breathing ? more difficult - characteristic wheeze on ?
overreaction
bronchial wall
narrows
out
expiration
Asthma cellular response
Allergen triggers ? production
which causes a ???? interaction and causes degranulation of ??
which eventually leads to ?, smooth muscle ? and ??.
IgE
B cell T cell
mast cells
oedema
constriction
mucus secretion
asthma is treated by modulating some of the inflammatory mediators
how do drugs ending in mab or ib often work, use omalizumab as an example?
often monoclonal antibody or biologic drugs
anti-IgE drug which will prevent IgE production preventing mast cells from degranulating
name the 3 features of asthma that cause bronchial narrowing
Bronchial smooth muscle contraction
Bronchial mucosal oedema -> swelling of the airway
Excessive mucous secretion into the lumen -> filling the airway
remember airflow is related to the radius to the power of 8 so small changes in the radius of the airway will significantly impact airflow
explain each symptom of asthma
Cough, wheeze (expiratory), shortness of breath
Diurnal variation
Difficulty breathing out and lungs fill with air
Caused by irritation from high levels of mucus being produced in the airway
Asthma often worse in the morning and overnight
Measure by falling peak expiratory flow rate (PEFR) over a few days which shows reduced airway patency
why is asthma a biphasic response?
There’s a first acute asthma attack and recovery
Then a late asthmatic response some hours later
how is an acute response of asthma managed?
acute beta agonists to open the airways quickly
how is a late response of asthma prevented?
low dose corticosteroid
asthma
if an acute beta agonist and low dose corticosteroid arnt adequate for controlling a pt asthma what is done?
increase corticosteroid to high dose and add long acting beta-adrenergic agonist
what is the clinical significance of aasthma being biphasic?
This is important to recognise as a patient sent home after management of the first response may then develop a more significant problem later
Ensure they get corticosteroids to prevent a late asthma response
Beta adrenergic receptors
Work by relaxing ???
- Reduce ?
- Reduce resting ??
Protective -> take in ? of attack e.g. ? exercise
Short acting -> ‘?’ drug
Long acting -> ‘?’ drug (must use with inhaled steroid)
bronchial smooth muscle
bronchostriciton
bronchial tone
anticipation
before
reliever
preventer
Corticosteroids
Work by reducing ??§, ?? and ?? which cause bronchial smooth muscle constriction
- Immune and epithelial cell action
mucosal oedema
mucus secretion
inflammatory mediators
what are the issues with corticosteroids?
risk of adrenal suppression and osteoporosis though there is no evidence that this happens with the inhaled steroid doses
Coronary obstructive pulmonary disease is a mixture of what 2 things?
reversible airway obstruction - bronchiectasis
irreversible lung disease - emphysema
in short what is bronchiectasis?
recurring damage to the airways caused by chronic infection.
Bronchiectasis aetiology -> recurring damage to the airways caused by chronic infection.
increase in ? from the disease process and inflammation. This happens ? in the same places leading to ? and ??? and damage to the ?? on the outside.
Airways are less ? and its difficult to ? mucus from them.
the mucous excess is caught in the airways and acts as a focus for ?
mucous
recurrently
scarring
thickened airway walls
muscle layers
responsive
clear
infection
what are the symptoms of bromchiectasis?
Productive cough often with green sputum
what is emphysema?
destruction of alveoli and dilation of others to fill the space (reduced SA for gas exchange)
how does emphysema lead to increase risk of cardiac failure?
increase in cardiac size as more work to pump blood round the body leading do cardiac failure being more likely
symptoms of COPD
Cough
Mucus
Fatigue
Shortness of breath
Dyspnoea - difficulty breathing
Chest discomfort
causes of COPD
Asthma
Pollution
Age
Smoking -> largest risk
Chemical exposure
Genetic - AAT deficiency
Chronic bronchitis
complications of COPD?
Pneumonia
Heart failure
Acute respiratory distress syndrome ARDS
Frailty
depression
remember
COPD risk assessment cant be based upon the medicine used (asthma can) as it is very specific to the patient
no drug based management of COPD 3
Smoking cessation
Prevention of flu
Pulmonary rehabilitation
inhlaed therapies for COPD are only given if non-drug based methods dont cause improvement
name 3 inhaled drug therapies for COPD
Beta agonists if features suggest reversibility of airways
Corticosteroids can be useful if significant inflammatory change
Oxygen support if there is failure of the respiratory system
when may it be necessary to give COPD patients antibiotics?
if they have acute COPD exacerbation from infection
what is type 1 respiratory failure caused by?
alveolar effects (hypoxia - lack of oxygen reaching tissues)
Reduced surface are for gas exchange
Thickening of alveolar mucosal barrier from scarring of the alveolar surface
what is a person with type 1 respiratory failure called based on their clinical presentation?
Pink puffer -> hyperventilate to increase oxygen conc. Gradient to compensate
how is type 1 respiratory failure diagnosed?
arterial oxygenation below 8kPa on air, easier to measure oxygen saturation <90%
what is type 2 respiratory failure caused by?
poor ventilation (CO2 retention and hypoxia)
Airway narrowing
Restrictive lung defects
- Muscle disease preventing ventilation
what is a person with type 2 respiratory failure called based on their clinical presentation
blue bloater
Oxygen levels fall and CO2 levels rise, which is mirrored in the blood and the patient becomes oedematous and hypoxic
how is type 2 respiratory failure diagnosed?
if arterial CO2 is above 6.7kPa
how is respiratory failure managed?
Giving oxygen 24hrs a day increases chance of survival as low level hypoxia makes acute coronary events much more likely
why must patients given oxygen with COPD be carefully monitored especially respiratory rate?
they rely on CO2 drive for their ventilation so it will reduce their need to breath
dental impact of COPD? 3
ability to attend appt. - O2 therapy
candida risk from oral steroids (rinse and spacer)
oral cancer risk as often smokers/ex-smokers
Cystic fibrosis is a ? disease where there is an inherited defect in ???
Mutation in the ? gene on chromosome ?
Causes the production of excess ? mucus and affects all ?? (mainly lungs and pancreas)
Lungs fill with sticky secretions. ? and ? also occur
Preventing ? is a large part of ensuring survival
genetic
cell chloride channels
CFTR
7
sticky
bodily secretions
bronchiectasis
emphysema
infection
diagnosis of cystic fibrosis 4
Prenatal screening
Perinatal testing - all children screened at 5 days with blood spot test
Sweat test -> greater salt content in CF patients as more chloride
CFTR gene testing -> specific mutation depends on ethnicity
symptoms of cystic fibrosis in children 4
Troublesome cough
Repeated pulmonary (chest) infection -> staph
Malnutrition -> from the lack of fat absorption and the inability of the pancreas to produce enzymes
Prolonged diarrhoea and poor weight gain -> Due to high fat content being passed through the gut
cystic fibrosis can lead to what? 4
Liver dysfunction
Prone to osteoporosis -> not absorbing fat soluble nutrients e.g. vit D
Diabetes symptoms -> chronic pancreatic inflammation gradually destroys B cells
Reduced fertility -> mainly men
one of the treatmnets for cystic fibrosis is physiotherapy, how does this help?
Help remove the mucus secretions out the lung (like a massage, done by parents)
what medication is given to treat lung problems associated with cystic fibrosis?
Bronchodilators to open airways
Antibiotics to reduce chest infection frequency
Steroids to reduce airway inflammation
what medication is given to treat the digestive system problems associated with cystic fibrosis?
Pancreatic enzyme replacement
Nutritional supplements
CFTR modulators can be given to cystic fibrosis patients
they change ?? regulation so there is a more normal response to stimuli
Only suitable for F508del patients which is 90% of patients
chloride channel
how do stem cell treatments help cystic fibrosis patients?
Replace bad gene with new one
Difficult as has to be given to stem cells (not stable ‘adult’ cells) so that all body cells have the new gene copy
how does exercise help cystic fibrosis patients?
Keep lung function optimal
Build physical bulk and strength
transplantation is a treatment option for cystic fibrosis that has lead to end stage lung disease
also effects the heart so lung-heart transplant)
10 year survival
Complications from the transplant suppression medicines
causes of lung cancer
- Smoking
- Genetics
- Other lung diseases
Environmental: chemicals, radon, air pollution, radiation therapy
Lung tumours can be a ? mass or a ? mass that blocks the ? allowing a collection of ? and ? in the lung resulting in ? and ? of the whole lobe of the lung.
peripheral
central
bronchus
fluid
inection
pneumonia
occlusion
almost all lung tumours are benign or malignant?
malignant
what are the 2 main types of lung cancer?
Small cell
Non-small cell (most common)
- Squamous cell carcinoma
- Large cell
- Adenocarcinoma
signs and symptoms of lung cancer
Cough
Haemoptysis -> blood stained sputum
Pneumonia -> from bronchi blockage
Metastasis -> bone, liver, brain
Other
- Dysphagia -> difficulty swallowing from central tumour at bronchus compressing the oesophagus
- Superior vena cava compression -> from tumour within mediastinum -> oedema as blood doesn’t return to right heart from upper body.
- Recurrent laryngeal nerve palsy -> persistent hoarseness from tumour in contact with laryngeal nerve -> may be first sign of lung cancer
Diagnosis of lung tumours
When a tumour starts there is a long time before symptoms develop and diagnosis so metastasis can occur leading to bad patient outcomes
what is stage 1 lung cancer?
Stage 1: one tumour
what is stage 2 lung cancer?
Stage 2: multiple lesions but only on one side of the thorax
what is stage 3 lung cancer?
Stage 3: lesions on both sides of the thorax
what is stage 4 lung cancer?
Stage 4: metastatic lesions throughout the lung and symptoms of oedema, fluid or pneumonia
Treatment of lung cancer
Dependant on ?
? (genetic mutations of the lesion) help decide what treatment is best
In locally advanced unresectable non-small cell lung cancer the treatment is ?? with the aim of prolonging life expectancy not ? the disease
In some peripheral solitary lesions ? of the infected lobe can be curable
stage
biomarkers
chemoradiation therapy
curing
removal
what is obstructive sleep apnoea?
airway obstruction whilst asleep preventing normal breathing for 10seconds or more.
symptoms of obstructive sleep apnoea
Drowsiness during the day as cant sleep -> car accidents
Snore
Problems associated with obstructive sleep apnoea
Its a multisystem problem but manifests as an ? problem
Affects the ? -> cognitive function etc.
? systems -> cardiovascular disease and insulin resistance (diabetes)
increased risk of ??? such as MI as hypoxia occurs during sleep apnoea
airway
brain
control
acute cardiac events
The number of times a obstructive sleep apnoea patient suffers obstruction during the night is key to their long term survival and need for treatment
how do mandibular advancement appliances help obstructive sleep apnoea?
Aims to move the tongue away from the pharynx. Move the mandible forward pulling the tongue with it
how does CPAP help obstructive sleep apnoea?
continuous positive airway pressure
Mask is worn to maintain pressure in the airways to blow apart the tongue and pharynx maintaining patency
how does positional therapy help obstructive sleep apnoea?
An alternative if obstruction only occurs when the patient sleeps on their back. Devices to encourage to sleep on side.
what drugs improve ventilation through improving airway patency?
Bronchodilators -> relax the smooth muscle
- B2 agonist and anticholinergic
Anti-inflammatory -> reduce mucosal oedema and mucus production
- Corticosteroids
what drugs improve ventilation through preventing mast cell degranulation?
Reduce inflammatory mediators released into the airway wall that cause narrowing of the airways
- Chromoglycate
- Leukotriene receptor antagonists
drugs that impair ventilation
?? -> Narrow airways by increasing airway smooth muscle constriction
??
- Benzodiazepines -> reduce ?? by causing muscle relaxation
- Opioids -> reduce the ? for the patient to ?
B blockers
respiratory depressants
ventilation rate
stimulus
breath
what drug is used to improve gas exchange?
Oxygen -> higher conc. In alveolus = more oxygen diffuses into blood
Remember oxygen is a drug so must be prescribed
what is the problem with a metered dose inhaler MDI?
fires a jet of drug into the oropharynx to be captured by the air being breathed in but a lot of the drug will be deposited around the oropharynx and may lead to local immunosuppression (especially corticosteroids) and candidiasis
inhaled drug delivery
what is a breath activated device?
Pics up the drug as the air moves across the device and carries it into the airway
Spinhaler, turbohaler
name two aids to inhaled drug delivery
Nebuliser
- liquid version of the drug
- The compressor blows air through the tube causing the drug to bubble and be breathed into the airway
Spacer
- useful for patients with a MDI
- Don’t need to coordinate activating the inhaler and the breath so effectively
- Activate device into chamber then take breath from chamber
B agonist
Relieve the symptoms of asthma by ?
relaxing the airway
short acting B agonists
? onset
administration ?
use?
quick
inhaled, oral, intravenous
Treats acute bronchial constriction
long acting B agonist
? onset
administration ?
use ?
slow
inhaled
prevents acute bronchial constriction
Always used with an inhaled steroid to reduce chance of acute coronary syndrome
what do anticholinergics do?
Cause relaxation of the smooth muscle and opening of the airways
Used with b agonists for bronchial dilation and mucus secretion reduction
what do corticosteroids do?
Reduce inflammation in the bronchial walls
how do mast cell stabilisers treat asthma?
Prevent the release of chemical mediators in the bronchiole wall which initiate asthma
how do leukotrine inhibitors treat asthma
Prevent the release of chemical mediators in the bronchiole wall which initiate asthma
how do biological medicines treat asthma?
Target specific immune modulators within the inflammatory process
