Lower respiratory tract diagnostics (3) Flashcards
(33 cards)
how does inflammation effect cough receptors?
causes them to become more sensitive
how does discharge compare in lower respiratory tract infection compare to upper?
lower you get a bilateral discharge
how does lower respiratory tract infection cause tachypnoea/dyspnoea?
pathology in the lungs causes reduced gas exchange leading to hypercapnia, acidaemia and hypoxaemia which is recognised by chemoreceptors in the aortic and carotid bodies
impulses send to the respiratory centre in the medulla to increase respiratory rate and effort
what effect does the horses having a huge respiratory capacity have on the clinical signs on respiratory disease?
they may not be apparent at rest (may need to exercise in cases of mild disease)
what posture suggests severe respiratory distress?
extended head and neck
what muscle hypertrophies to cause heave lines?
external abdominal oblique
what sound is normally associated with collapse?
wheeze
what is likely to cause an inspiratory wheeze?
upper respiratory collapse
where is an inspiratory noise most likely to be localised to?
upper respiratory tract
is lower respiratory collapse more likely to cause an inspiratory or expiratory noise?
expiratory
where is the loaded respiratory noise heard in a normal horse?
tracheal bifurcation
what are normal breath sounds?
turbulent air in large airways causing a soft blowing sound that are louder on inspiration
are normal breath sounds heard more on inspiration or expiration?
inspiration
what are the adventitious sounds of the respiratory tract?
wheezes
crackles
pleural rubs
what causes a wheeze?
narrowing of airway causing vibrations
what are some possible causes of respiratory wheezes?
thickened walls (oedema/inflammation)
intraluminal obstructions
bronchospasm
extraluminal compression
what usually causes monophonic wheezes?
single areas of airway obstruction/narrowing
what are the two types of crackles?
coarse
fine
what causes coarse crackles?
bubbling mucous in airway
what causes fine crackles?
opening of collapsed small airways
when are fine crackles usually auscultated?
early inspiration
what causes pleural friction rubs?
inflamed parietal and visceral pleural membranes rubbing together
how can respiratory sounds be exaggerated?
making horse work
making horse rebreathe (put bag over head)
what can thoracic percussion be used for?
assess for fluid (more resonance means more fluid) - looking for changes in resonance
