Small animal Collapse Weakness and Exercise intolerance Flashcards
Why is the owners description of collapsing episode key
the vet rarely sees the episodes so the owners description is essential to ensure correct diagnosis
After a collapsing episode what is the most important thing to establish
what type of collapse it was- seizure, weakness, syncope, ect
and what system was involved in the primary issue
Why is it important to establish when fits happen
if they happen at regular times they may be related to something- exercise, before feeding, after feeding
if we don’t find any physical abnormalities on clinical exam after a collapsing episode, what can we do
we can wait and see if it occurs again - 75% of humans will only have one collapsing episode
what is syncope
fainting- sudden, short-lived loss of consciousness
what causes syncope to occur
temporary failure of delivery of energy substrate - (oxygen and glucose ) to the CNS
how long must the CNS be without blood before syncope occurs
at least 6 seconds
List the clinical signs of syncope
sudden onset
generalised weakness/ ataxia
flaccid collapse
consciousness lost
autonomic signs
Describe vasovagal syncope
sudden faint due to hypotension induced by response of the autonomic nervous system to abrupt emotional stress, pain or trauma
what dog breed commonly gets vasovagal syncope
boxers
what is carotid sinus syncope
fainting due to inappropriate stimulation of the carotid sinus barorecptors in the thorax or neck
what is tussive syncope
Syncope caused by strong coughing - increased thoracic pressure causes reduced venous return to the heart and therefore reduced output
3 differential categories causing syncope
inappropriate vascular reflexes
cardiac
non-cardiac
cardiac issues causing syncope
dysrhythmias
flow obstruction
pump failure
tamponade
list non-cardiac issues causing syncope
metabolic
central neurological
List the diagnostic tests to investigate syncope- in order from most useful to least useful
haematology and clinical biochemistry
ECG
thoracic/ abdominal radiography
ECHO
if you don’t find anything on ECG but you suspect a heart problem, what should you do
place the animal on a 24 hour ECG monitor- holter
Why is a very high heart rate dangerous
the heart won’t have time to fill properly and therefore output will be reduced
what does it mean if the P waves are negative
the SAN is firing abnormally and the atrium is contracting in the wrong direction (from the bottom up)
describe a holter monitor
a portable electrocardiograph that is worn by an ambulatory patient to continuously monitor the heart rates and rhythms over a 24-hour period
what is episodic weakness
intermittent/ persistent exercise intolerance
what diagnostic tests would we do for episodic weakness
this depends on what system we think is diseased.
metabolic - biochemistry
neuromuscular - edrophonium response test / anti-Ach
muscular - EMG and mm biopsy
cardiorespiratory - haematology and biochemistry, ECG
what are 3 groups of diseases that can lead to seizures
extracranial disease
structural intracranial disease
functional intracranial disease
what tests can we do to investigate seizures
CSF analysis
biochemistry
radiography
MRI/ CT
what can we do if we can’t figure out the cause of the collapse/seizure/weakness
try and induce the problem to investigate - run tests to get the max infor for the min price
how often do you come to a diagnosis of syncope, collapse and exercise intolerance
50% of the time
can be challenging to diagnosis
