COPD Flashcards
COPD is an umbrella term for..
Emphysema
Chronic bronchitis
Chronic Asthma
Symptoms of Emphysema
Pink puffers difficulty breathing, well perfused barrel chest muscle wasting (thin) Pursed lips
Symptoms of Bronchitis
Blue bloaters - severe dyspnoea and lack of exercise
cynosed
peripheral oedema
raised JVP (R side HF)
Symptoms of both
Dyspnoea
Chronic cough
less common - wheezing
chest tightness
difficulty breathing
Pathology of emphysema
Affects alveoli of the lunges
Alveoli are covered with elastic fibres allowing them to expand and recoil back pushing air out as we exhale
loss of elastic fibres - decrease in surface area of alveoli - collapsed alveoli
Air trapping within alveoli as we exhale because recoil mechanism is not working
Chronic Bronchitis pathology
problems along airway tract specifically bronchioles. Normall bronchiole have smooth muscle and mucus however in bronchitis the muscle hypertrophys and contraction and mucus hypersecretion leads to difficulty breathing
COPD risk factors
Smoking advanced age low socio-economic factors constant exposure to air pollution genetic factors - Alpha 1 dvpmt abnormal lungs low birth weight recurrent infections cannabis smoking
Pathophysiology of Emphysema
inflammatory response → elastic fibre breakdown and destruction of alveolar walls → loss of alveolar integrity → loss of alveolar recoil → air trapping
What do Endogenous microphages do?
reside within alveolus and help to keep it clean and sterile
How do toxic substances stimulate macrophages
produce proteases and cytokines
What do Cytokines release? and how does it affect ventilation?
release and attract neutrophils from circulation to move into the area → neutrophils secrete elastase which specifically targets elastic tissues → loss of elastic fibres around the alveolus → loss of elastic recoil → decrease in ventilation
How do Macropheges affect perfusion?
proteases are secreted by macrophages and neutrophils
lead to destruction of alveolar wall and capillary beds – decrease in perfusion
what does air trapping mean? and how does it effect inspiratory volume
when you still have a lot of gas trapped in the alvelous after you exhale
increase in end IV - barrel chest
what causes air trapping?
Loss of elasticity and destruction of alveolar wall
V/Q mismatch is?
decrease in perfusion and decrease in ventilation
in blood decrease o2 and increase co2
what does loss of elastic recoil lead to?
loss of alveolar integrity → work a lot harder to breathe in → dyspnoea & cachexia
What hereditary condition is linked to COPD
Alpha 1 antitrypsin deficiency
if deficient cant defend against proteases - increase in proteases and decrease in anti-proteases resulting in net damage to lungs
Chronic bronchitis inflammatory change leads to
mucociliary dysfunction
Chronic bronchitis increased goblet cell secretion and numbers leads to
excessive mucus production
Chronic bronchitis Where do we see bronchoconstriction and mucus hypersecretion (
in bronchioles and bronchi
Chronic bronchitis mucus hypersecretion leads to
productive cough
airway obstruction leads to
wheezing (usually expiration)
Alveolar hypoxia is
oxygen not getting through to alveoli efficiently → V/Q mismatch → hypoxaemia and hypercapnia
Chronic obstruction results in
less oxygen in and less CO2 out → decrease in O2 in blood and increase in CO2 in the blood
COPD risk factors
Smoking (95%) Advanced age Low socio-economic factors Constant exposure to air pollution Genetic factors Alpha-1 antitrypsin deficiency Developmentally abnormal lungs - predisposes one to COPD Low birth weight Recurrent infections Cannabis smoking
How is COPD assessed
severity of symptoms
spirometry
risk of exacerbation
Observation of Emphysema
Prolonged expiratory phase → trying to push the air out of lungs PLB Over distension of lungs/barrel chest Use of accessory muscles Decrease in intensity of breath sounds
what are you looking for in COPD in pulse oximetry
O2 saturation and hypoxaemia
COPD ABGs you should check
pH
Typically in late stage COPD - respiratory acidosis
CXR for COPD
Hyperinflation
Lung larger than normal (greater expansion?)
Heart may look longer than normal
Pulmonary hypertension - prominent hila vascular shadow
Flattened diaphragm - lower and flatter than usual
Darker within the lung
Lung shadow darker because a lot of trapped air
Emphysema - bullae (pockets of air that can get up to 1 cm)
Fluid build-up
Criteria for diagnosis of COPD is spirometry
Decrease in FEV1
Decrease in FEV1/ FVC <70%
Auscultations for COPD
Emphysema
Prolonged expiratory phase
Decreased intensity of breath sounds
Inspiratory + Expiratory Wheeze - Bronchospasm
Coarse crackles - airway closure from mucus
Prolonged forced expiration - to prevent airway walls collapsing during expiration
Paradoxical quiet breath sounds
management of COPD
Oxygen therapy surgical intervention pulmonary rehab steriods inhalers bronchodilators smoking cessation vaccine - prevent exacerbation of copd
