Diseases of the Urinary System and Therapeutics Flashcards
Are the kidneys in the intra- or retroperitoneal space?
Retroperitoneal
Which kidney is more cranial?
Right slightly more cranial than left
What is azotemia?
Elevation of urea and/or creatinine in the bloodstream
What is uraemia?
The clinical signs associated with azotaemia
What is polyuria?
Excessive urine production
What is oliguria?
Production of a very small amount of urine (inadequate)
What is anuria?
Absence of urine
What is polydipsia?
Excessive water intake
What is pyelonephritis?
Bacteria kidney infection (may be unilateral or bilateral)
What is glomerunephritis?
Inflammation of the glomeruli
What is renal insufficiency?
A measurable reduction in kidney function
How long must pass before kidney disease is considered chronic?
> 3 months
What is usually the first readily measurable sign of kidney disease?
Inability to concentrate urine
What is hypersthenuria?
Excretion of urine with an unusually high specific gravity
What is hyposthenuria?
Excretion of urine with an unusually low specific gravity
What USG is considered normal for cats and dogs?
Dogs >1.030
Cats >1.035
What USG is considered hyposthenuria?
<1.008
What main types of urinalysis are there?
USG testing Dipstix analysis Microscopy Cytology Bacterial culture and sensitivity
Why do we test specifically for urea and creatinine?
They are both endogenous waste products excreted by the kidneys (= good measure of kidney function)
Why should you take a fasted blood sample?
A recent protein meal will falsely raise urea
What does azotaemia indicate in terms of kidney function?
Indicates reduced glomerular filtration of blood
What causes pre-renal azotaemia?
Inadequate renal perfusion
What causes renal azotaemia?
Reduced functional mass of the kidneys due to underlying kidney disease
What causes post-renal azotaemia?
Obstruction of the ureters or urethra
Rupture of the urinary tract (= uroabdomen)
What is the body’s response to a pre-renal azotemia?
To preserve as much water as possible = production of concentrated urine
What is the result (urine-wise) of a renal azotemia?
Poorly concentrated urine (less than hypersthenuria)
What effect can kidney disease have on phosphates in the blood?
Hyperphosphataemia common - reflects reduced renal function
What effect can kidney disease have on potassium levels?
Hypokalaemia common as a direct consequence of kidney disease - contributes to weakness and inappetence
What effect can kidney disease have on red blood cells?
Anaemia = erythropoietin is synthesised by the kidney
RBCs in uraemic px have a reduced lifespan
With what type of kidney damage will patients present more unwell?
Acute kidney injury
What level of urine excretion do acute kidney injury patients commonly present with?
Anuria or oliguria
What common toxins can cause acute kidney injury?
Cholecalciferol (vit D) Ethylene glycol (antifreeze) Grapes/raisins Lilies (cats only) Ibuprofen/NSAIDs
What are the clinical findings you expect with acute kidney dysfunction?
Lethargic, depressed
Inappetent and nauseous
Cardiac arrhythmias/arrest
Volume overload (an/oliguria)
What specific clinical sign do you see with ethylene glycol toxicity?
Tremors (hypocalcaemia)
What specific clinical sign do you see with leptospirosis?
Icterus
What blood findings are used to diagnose acute azotemia?
Increased urea/creatinine/phosphate
Increased K+ if anuric/oliguric
Decreased K+ if polyuric
How should AKI be managed?
Remove underlying cause (nephrotoxic drugs/toxins/gastric decontamination)
Manage fluid balance/electrolytes/uraemic toxins
Supplementary management of nutrition/nausea/pain
Which crystalloids are most appropriate for managing AKI?
Hartmanns
What are the main objectives for initial fluid therapy of AKI?
Correct any hypovolaemia (pre-renal component)
Once euvolaemic, correct any dehydration (0ver 6 hours)
What are the effects of hyperkalaemia on the heart?
Reduced pacemaker activity
May be bradycardic
Ventricular fibrillation
Cardiac arrest if severe
How can hyperkalaemia be identified on an ECG trace?
Wide QRS
Flattened P
Spiked T
What is the purpose of giving calcium gluconate for hyperkalaemia?
Helps stabilise the myocardium
What is the purpose of giving glucose and/or insulin for hyperkalaemia?
Glucose stimulates release of insulin
Insulin stimulates uptake of potassium into cells
What specific therapy should be used for ethylene glycol toxicity?
Medical-grade ethanol
What type of therapy should be used to treat leptospirosis/pyelonephritis?
Antibiotics
What are the indications for dialysis or euthanasia?
Persistent anuria +/- volume overload
persistent unmanageable hyperkalaemia
What treatment should be considered if px fails to respond to treatments for anuria?
Consider trial diuretic - 2mg/kg frusemide ONCE
