ELFH - Respiratory disorders and the dental patient Flashcards
What respiratory diseases will be focused on?
asthma and chronic obstructive pulmonary disease (COPD)
What is asthma?
an inflammatory disorder characterised by reversible airway obstruction
a chronic inflammatory disorder of the lower airways resulting in recurrent episodes of dyspnoea, cough and wheeze due to reversible airway obstruction
Symptoms of chronic obstructive asthma?
chronic nocturnal cough
wheeze
breathlessness
When are chronic asthma symptoms worse?
in the morning around 3am and there is diurnal variation.
What could be a trigger of asthma?
cold air
exercise
smoke
house dust mites
drugs such as non steroidal anti-inflammatory drugs (NSAIDs) and beta blockers also precipitate asthma
Drugs which could trigger asthma?
drugs such as non steroidal anti-inflammatory drugs (NSAIDs) and beta blockers also precipitate asthma
What art of the airway does asthma affect?
lower airway
Word for difficult or laboured breathing?
dyspnoea
2 forms of asthma?
extrinsic
intrinsic
Commonest type of asthma?
extrinsic
What is extrinsic asthma?
‘atopic asthma’ is of an allergic nature.
exposure to an extrinsic allergen results in a histamine-mediated chain of events
It is associated with hayfever and eczema. Exposure to allergens at work and to drugs are also classed as extrinsic asthma.
What is extrinsic asthma associated with?
It is associated with hayfever and eczema.
Exposure to allergens at work and to drugs are also classed as extrinsic asthma.
How would you describe the chain of events n extrinsic asthma?
histamine-mediated chain of events
What is intrinsic asthma?
non-immune triggers, that have little or no effect on normal subjects, result in the symptoms of asthma
more common in older pts
intrinsic asthma is not associated with allergic pathways
it is seen with pulmonary infections, cold air, stress an exercise
What type for asthma is more common in older pts?
intrinsic asthma
What triggers intrinsic asthma?
pulmonary infections, cold air, stress an exercise
Airway hyper-responsiveness?
Exposure to a precipitant in a predisposed individual results in specialised immune cells (mast cells) releasing pro-inflammatory chemicals, the most important of which is histamine.
These act on airway epithelial and smooth muscle cells causing airway narrowing, that is bronchoconstrictor response, resulting in the classic symptoms of asthma.
3 main mechanisms resulting in the classic symptoms of asthma?
Airway hyper-responsiveness causes…
bronchial muscle contraction
mucosal swelling or inflammation
mucous production
Stepwise management of asthma according to BTS guidelines?
step 1: give inhaled beta-2-receptor agonists
step 2: add inhaled corticosteroids
step 3: increase inhaled steroid, add long-acting beta-2-receptor agonist
step 4: trial other anti-inflammatories, for example, aminophylline, montelukast
step 5: give oral steroid therapy
what is the first call of action with chronic asthma?
inhaled beta 2 receptor agonist
step 2 in management of chronic asthma?
inhaled corticosteroids
What is COPD?
characterised by progressive airway obstruction with little or no reversibility
it encompasses both chronic bronchitis and emphysema - rarely a pure disease
emphysema?
result of permanent damage to the distal airspaces resulting in impairment of lung function and gaseous exchange, with potential retention of CO2.
shortness of breath
2 diseases contributing to COPD?
both chronic bronchitis and emphysema
chronic bronchitis?
chronic inflammation of the airways leading to excessive secretion and sputum production.
physical obstruction of airways and cough
What age group does COPD typically affect?
those aged over 35 yo
most important aetiological factor?
smoking
typical symptoms of COPD?
- daily productive cough
- shortness of breath
- frequent chest infections
Patients may develop acute exacerbations of COPD which may need to be managed as a medical emergency.
What causes chronic bronchitis?
Smoke results in damage to the lining of the airways, preventing normal function and irritant clearance. In response, mucus glands enlarge and change, resulting in excessive mucus production.
Continued damage causes the airways to fibrose.
The hallmark is a physical obstruction of the airways.
2 causes of cause of emphysema?
can be genetic (alpha-1 antitrypsin deficiency) although most is due to smoke damage.
Why does smoking cause emphysema?
Chemicals and free radicals in smoke recruit inflammatory cells which release enzymes and mediators which damage the airway epithelium.
Terminal airspaces become thin and lose their ability to ‘deflate’ (elastic recoil), hence air in them is trapped and cannot be exhaled efficiently. This makes breathing incredibly difficult to move the gases.
The hallmark is a functional airway obstruction
In contract to asthma, what are characteristics of COPD?
- are older; age over 35 years
- are smokers
- have persistent, chronic shortness of breath
- produce sputum
- have no daily variation in symptoms
Overtime can COPD affect the heart?
yes, poor oxygenation puts stress on the pulmonary vessels and the heart, which can result in cardiac failure (Cor pulmonale).
Treatment for COPD?
the inhaled beta-2-antagonists, as are inhaled corticosteroids
anti-cholinergic preparations are used
Aim of beta-2-agonists?
aim to relax the smooth muscle of the airways and reduce obstruction
Example of beta-2-antagonist?
include ipratropium bromide and tiotropium.
What will pts with long term COPD be on?
long-term oral steroids such as prednisolone.
pts with servere COPD way warrant at home oxygen
Do pts with asthma have increased chance of dental caries?
yes
Why are asthmatic pts at increased risk of cares?
This is thought to be secondary to reduced saliva production following long-term use of inhaled beta-2-agonists.
What are inhaled steroid associated with?
oral mucosal changes
oral candidiasis
xerostomia; dry mouth
gingivitis
Is dental care compromised in pts with well controlled COPD?
In patients with stable, well-controlled asthma or COPD, dental care should not be affected.
Should you delay tx in symptomatic pts?
yes, until symptoms have resolved
Can dental procedures exacerbate COPD and asthma?
yes, especially asthma
what dental procedure exacerbates asthma the most/ most commonly?
patients receive a local anaesthetic whilst undergoing a stimulating procedure such as a tooth extraction
also… particularly tooth enamel dust and dentifrices
Considerations for pts with COPD or asthma with regards to dental procedure?
elective procedures - when pt is symptom free
oxygen availability
time of appointment
preventative measures
opiates
safe drugs
oxygen availability during dental procedure?
Before commencing a procedure, the dentist should ensure that oxygen is available and that the patient has their bronchodilator with them.
time of appointment for dental procedure and pt with asthma/copd?
It may be beneficial to have the appointment later in the day, as many asthmatics have worse symptoms in the mornings.
Monitoring may be useful, with a focus on the oxygen saturations:
target saturations in asthma: 92% to 94%
target saturations in COPD: 88% to 92%
preventative measures for a pt with copd/asthma and getting a dental procedure?
There is some evidence to suggest that prophylactic use of the bronchodilator and a histamine H1 receptor antagonist (to dampen any immune response) can improve lung function prior to the procedure.
Opiates and COPD/asthma an dental procedure?
Opiates, due to their respiratory suppressant properties, should be avoided as these can lead to a deterioration of asthma and COPD in some patients.
In such cases, it may be wise to seek medical advice or perform the procedure in a hospital setting.
sedation drugs?
benzodiazepine: diazepam and midazolam
safe drugs to use for sedation and analgesia in COPD/asthma pts?
drugs to avoid with pt with COPD/asthma?
opiates
NSAIDs, such as ibuprofen or diclofenac, should be avoided in patients with COPD or asthma. They should not be used without the full support of the patient’s medical practitioner.
Chronic bronchitis causes a functional airway obstruction?
False. Emphysema causes a functional airway obstruction (airways collapse during expiration); chronic bronchitis causes a physical obstruction of the airways.
Asthma is characterised by reversible airway obstruction?
True. It is the hallmark of asthma; beta-2 agonists are used to reverse the obstruction caused by bronchoconstriction.
Inhaled beta-2-receptor agonists are used as preventers in asthmatics with frequent symptoms?
False
inhaled beta-2-receptor agonists are used as relievers in most asthmatics; inhaled corticosteroids are used daily as preventers in asthmatics with frequent symptoms.
inhaled anti-cholinergic preparations can be used in patients with COPD?
True
They aim to relax the smooth muscle of the airways and reduce obstruction.
Steroids have no role in the management of asthma and COPD?
False.
Steroids play a major role in the BTS guidelines; they dampen an individual’s immune system and hence have greater effect in asthma than in COPD.
Many dental procedures have the potential to exacerbate both COPD and asthma. What does the dental practitioner have to consider for patients with COPD or asthma?
Elective procedures should be undertaken when the patient is symptom-free or optimised to the best they can be.
Oxygen should be available and the patient should have their bronchodilator with them.
An appointment later in the day would be more beneficial for asthmatic patients as symptoms are usually worse in the mornings.
Prophylactic use of the bronchodilator and a histamine H1 receptor antagonist can improve lung function prior to the procedure.
Opiates should be avoided as these can lead to a deterioration of asthma and COPD in some patients.
