Respiratory Disorders Flashcards
what 2 ways are non-infectious chronic lung diseases classified as?
obstructive or restrictive
what are the FEV1 and FCV measurements?
FEV1 = forced expiratory volume in 1 second
FVC = forced vital capacity
Basing on FEV1 and FVC, how do you know if a non-infectious chronic lung disease is obstructive or restrictive?
FEV1:FVC ratio - normal = 0.75-0.8
if less than 0.7 = obstructive
if it is high = restrictive
give 3 obstructive lung diseases.
asthma
chronic bronchitis
emphysema
define asthma and the two types
obstructive lung disease which is IgE-mediated
type 1 - reversible hypersensitivity
type 2 - allergic inflammation
Atopic - caused by allergen and sensitisation
Non-atopic - no evidence of antigen sensitivity
what can trigger asthma?
allergens
chemical irritant
strong smells
temp change
exertion
stress
describe the aetiology and pathogenesis of athsma
aetiology
- immunological reaction
pathogenesis
- person exposed to stimulus antigen
- elicit T cell response
- IgE antibodies produced, stay on mast cells
- re-exposure
- antibodies bind to antigen
- mast cells degranulate
- release inflammatory mediators
= bronchospasm
= vascular permeability
= oedema
= narrow airway
describe the clinical features of asthma
bronchospasm
airway inflammation
oedema
episodic bronchoconstriction
- due to increased airway sensititivty
- inflammation of bronchiole walls
- increased mucus secretion
cought, wheeze, dyspnoea, tight chest
use accessory muscles in chest
how is asthma managed?
short-acting relievers
- inhaled b2 antagonists
- salbutamol, terbutaline
long-acting reliervers
- inhaled b2 antagonists
- salmeterol, formoterol
- inhaled corticosteroids
- beclometasone, budesonide, fluticasone
bronchodilators
- inhaled antimuscuranic agents - ipratropium
- oral corticosteroids - prednisolone 40mg daily
steroid sparing agents
define chronic obstructive pulmonary disease
a group of diseases causing airflow blocking and damage is irreversible
what 2 obstructive lung diseases come under COPD?
chronic bronchitis
emphysema
describe chronic bronchitis and the pathogenesis
a persistent cough with sputum production
- for 3 months or 2 consecutive years
- no other identifiable causes
pathogenesis:
- chronic airway irritation - 90% smoking
- epithelium lining airway damaged
- dysfunctions cilia
- mucous hyper secretion
- mucus gland hypertrophy
- goblet cells metaplasia
=== lots of mucus secreted into airways
= obstruction - chronic inflammation
= fibrosis
= obstruction - decreases alveolar ventilation
- decreased gas exchange
- alveolar hypoxia
= ventilation mismatch
= pulmonary vasoconstriction
overall result of chronic bronchitis? (3)
hypoxaemia - low oxygen in the blood/low partial pressure in blood
hypercapnia - excess carbon dioxide in the blood - not expelling it
pulmonary hypertension - due to pulmonary vasoconstriction
describe emphysema and its pathogenesis.
irreversible abnormal enlargement of airspace distal to terminal bronchioles, with damage to alveolar wall and capillary beds
pathogenesis:
- airway irritation - smoking
- inflammatory response - cytokines, proteases
- alveolar connective tissue breaks down
- capillary bed gets damaged
- loss of recoil
- bronchioles collapse
- airways obstruct
- affects different parts of acini - small air sacs on alveoli
what are the two types of emphysema? describe the difference.
centriacinar emphysema
- if the emphysema occurs further up the bronchiole, next to respiratory bronchiole
panacinar emphysema
- if the emphysema occurs terminal to alveolus
describe the aetiology of COPD
aetiology
- smoking
- obstructive lung disease
- reduced expiratory flow
describe the 9 clinical features of chronic bronchitis
described as blue bloaters:
- larger people
- mild dyspnoea
- cough/wheeze due to mucous hypersecretion
cyanotic - from less o2 and more co2
hypoxic drive
- because theres so much co2
- become co2 tolerant
- rely on low o2 for respiration
- if you give patient o2, body cannot respire it and become stimulated
- can fall into type 2 respiratory failure
polycythaemia - due to low o2, tries to compensate by producing lots of RBC = blood more viscous
right heart failure - from pulmonary hypertension from pulmonary vasoconstriction and polycythaemia
oadematous - fluid retention = bloating
describe the 5 clinical features of emphysema
described as pink puffers
-thinner people
pursed lips
- alveolar air trapped in the acini
- loss of elastic recoil
- pursed lips to try create pressure in the lungs
severe dyspnoea and cachetic
- cachetic = weak and wasting away
- hyperventilation to maintain oxygenation
barrel chested
- use accessory muscles in the chest to help with respiration
- large end expiratory volume
how may you manage patients with COPD?
- beta-antagonists
- muscarinic antagonists - block ach from proliferating fibroblasts
- steroids
- oxygen - be careful with hypoxic drive
- smoking cessation
define tuberculosis
an infectious disease caused by mycobacterium tuberculosis
describe the two types of tuberculosis
primary tuberculosis
- unexposed
- non-immune host
- 95% asymptomatic
secondary tuberculosis
- from prev exposure
- immune host
- latent state
- reactivates
what is it called when TB spreads to the rest of the body?
miliary tb
- spreads from lungs to liver, spleen etc
describe the clinical features of tuberculosis
cough
malaise
weight loss
fever
haemoptysis
night sweat
pain on breathing
lymphadenopathy
back pain
heart failure
neurological symptoms
how is TB diagnosed and treated?
Mantoux test - skin prick test
histology
microbiology
treated with antimicrobial therapy
what are the relevant clinical guidelines of dental treatment in patients with COPD?
- keep upright
- avoid rubber dam
- avoid sedation
- monitor oxygen - saturation should be 88-92%
- if in respiratory distress, give high flow oxygen and adjust
what are the clinical guidelines for patients with asthma?
- always ensure patient has inhaler, ideally with spacer
- dont hesitate to ring 999
- sit upright, slow steady breaths
- appointment times later in the day for those worse in the morning
- avoid aspirin
does asthma increase risk for caries?
yes, by double
what are the dental considerations with TB?
vaccination against TB
infection control
