Equine 8 Flashcards
(46 cards)
what is SIRS triggered by
bacterial toxins
- lipopolysaccharide derived from gram negative bacteria
- gram positive organisms partocularly S aureus
- burns, neoplasia, pancreatitis (small animals)
lead to inflammation causing cell death and apoptosis
what is SIRS
self-amplifying dysregulated systemic inflammatory response
what is sepsis
SIRS plus culture proving infection (humans, generally just assume in animals)
what is severe sepsis
sepsis with organ hypoperfusion or dysfunction (measure with renal output)
what is septick shock
severe sepsis plus systemic hypotension
common in foals, rare in adult horses
what is multi-organ dysfunction syndrome
altered organ function in an acutely ill animal such that haemostasis cannot be maintained without intervention - horses inevitably die
what is primary MODs
resulting from well-defined insult where the organ dysfunction occurs early and is a direct consequence of the insult itself e.g. burns, neoplasia
what is secondary MODs
organ failure not in direct response to the insult but as a consequence of SIRS
what is DIC
disseminated intravascular coagulation - pathological activation of coagulation
- microvasculature clotting
- haemorrhagic diathesis
- consumption of procoagulants
what is DIC associated with
SIRS
sepsis
septic shock
MODs
what are the clinical signs of DIC in horses
thrombosis
petechial haemorrhage more common in foals
rarely - bleeding following trauma
how is DIC diagnosed in horses
3 of the 5 below = Thrombocytopenia = Prolonged prothrombin time ○ Prolonged activated partial thromboplastin time ○ Increased fibrin degradation products = Decreased antithrombin 3 also low fibrinogen but not often used
what are the common sequelae of GI disease in horses
SIRS or sepsis Hypovolaemia ○ acute pre-renal disease Dysregulation of perfusion ○ Some patients have ok circulation but capillary beds shut down (exchange site) so tissues become hypoxic Hypoproteinaemia Ileus Nutritional challenges ○ Poorly functioning gut doesn't absorb food effectively ○ Hypovolaemia means blood supply to GIT is reduced Change in gut flora Thrombophlebitis Coagulation abnormalities Pain
what are the less common sequelae to GI disease in horses
Ventricular dysrhythmias ○ Especially with GDV/LCV (dog/horse) Laminitis (horse) Vomiting (dogs, cats) Electrolyte abnormalities ○ Common ○ K increase in GDV ○ Low Na and Cl with diarrhoea ○ Increased Na and Cl with hypovolaemia and low Mg and K - colic - Mg and K increased by eating ○ Treat if life-threatening, otherwise leave kidneys to sort Anaemia
which factors must be corrected early in the critically ill patient to improve prognosis
hypovolaemia
electrolyte disturbances
hypotension
SIRS - some cases need surgery
need appropriate use of antimicrobials
what are the clinial signs of hypovolaemia in horses
- mm colour congested or white
- increased CRT
- increased HR
what are the clinical pathological signs of hypovolaemia in horses
• Increased creatinine - horse • Increased urea and creatinine - dog - USG >1.030 in conjunction with other signs • Increased lactate • PCV and TP
what factors are used to monitor improvement of hypovolaemia in horses
• HR normalising
• Improved demeanour
• Repeat USG or starting to produce urine when previously anuric
• Repeat bloodwork max q4hours
○ Repeat lactate
§ Produced by cells. If you have had capillary bed shut down then fluids given, the beds open up and then lactate will double so need to take care with interpretation
describe the approach to hypovolaemia in horses
• Assess percentage fluid deficit (not dehydration)
• Calculate maintenance rates
○ Adults = 2ml/kg/hr
○ Neonates 2x adult rate ~5ml/kg/hr
• Replace 50% fluid deficit as bolus as fast as you can
○ Large bore, short catheter, hang fluids from a height
○ Re-examine animal at this point
• Replace remaining 50% and maintenance over the next 6-8 hours
○ Include fluid estimate of loss due to reflux/diarrhoea etc
○ Need to correct underlying problem
why should oral fluids be avoided in cases of ileus
- won’t be absorbed
- will distend small intestines as not moving through
- will cause discomfort/pain
what electrolyte imbalance may be seen in horses that have had food withheld with resuscitation fluids
hypokalaemia
hypomagnesemia
which electrolyte imbalance may be seen in horses that have diarrhoea
low Na
low Cl
which electrolyte imbalances may be seen in hypovolaemia
slightly high Na and Cl
which electrolyte imbalance may be seen in horses with LCV
hyperkalaemia and cardiac dysrhythmias secondary to muscle necrosis (rare)
