cardiovascular week 5 Flashcards
What is tidal volume?
During normal quiet breathing, about 500ml in and out of lungs with each breath
What is IRV?
inspiratory reserve volume
the amount of air that can be inspired past tidal volume
What is ERV?
expiratory reserve volume
the amount of air that can be expired after tidal expiration
What is residual volume/
after the most strenuous expiration, about 1200ml of air remains in the lungs
What is IC?
inspiratory capacity
the total amount of air that can be inspired after tidal expiration
What is FRC?
The functional residual capacity
the amount of air in the lungs after tidal expiration
What is VC?
vital capacity
the total amount of exchangeable air
What is TLC?
total lung capacity
the some of all lung volumes
usually about 6L in males
What is FEV1?
Forced expiratory volume in one second
What is FVC?
forced vital capacity
Describe the ratio of FEV1/FVC
expressed as a percentage
reduced in obstructive diseases
sustained in restrictive
What is peak respiratory flow?
maximum expiratory flow that can be sustained for a minimum of 10ms
What is COPD?
chronic obstructive pulmonary disease
name for a collection of lung diseases including chronic bronchitis, emphysema and chronic obstructive airways disease
What are the typical symptoms of COPD?
increasing breathlessness when active
persistent cough with phlegm
frequent chest infections
other signs - weight loss, tiredness, swollen ankles
What causes COPD?
mainly smoking
smoking irritates and inflames the lungs which result in scarring
inflammation leads to permanent changes in the lung - walls of airway thicken, more mucous is produced
damage to the delicate walls of the lungs causes emphysema and the lungs to lose their normal elasticity
smaller always become scarred and narrowed
What are rarer causes of COPD?
fumes
dust
air pollution
genetic disorders
What is emphysema?
an abnormal enlargement of the alveolar airspaces distal to the terminal bronchi
What are the four types of emphysema?
centrilobular
pan lobular
paraseptal
irregular
What are the three primary systems that regulate the H+ concentration of the body fluids to prevent acidosis or alkalosis?
the chemical acid-base buffer systems of the body fluids, which immediately combine with an acid or base to prevent excessive changes in H+ concentration
The respiratory centre, which regulates the removal of CO2 from the extracellular fluid
the kidneys, which can excrete either acid or alkaline urine
What are the fast acting lines of defence against changes in body pH?
buffer systems
respiratory system
What is the more slowly acting defence against changes in pH?
The kidneys (hours to days)
What are the main buffer systems?
bicarbonate
proteins - haemoglobin
What can cause respiratory acidosis?
impaired lung function
How does emphysema cause acidosis?
less CO2 expiration
build up of CO2
build up of H+
acidosis
What is the kidney’s response to alkalosis?
secrete less H+
fail to resorb all filtered HCO3-
What are the three ways that the kidneys respond to acidosis?
secretion of H+
resorption of filtered HCO3-
production of new HCO3-
How can COPD be differentiated from asthma?
COPD should not be reversible with bronchodilator
asthma would respond to BD in terms of FEV1 volume
gas transfer would be reduced in COPD but not in asthma
Describe obstructive respiratory condtions
rate of flow is reduced
Describe restrictive lung conditions
rate of flow is normal but lung volumes are reduced
