Urinary Flashcards
clinical presentations of UT disease
stranguria - straining to urinate
hematuria - blood in urine
dysuria - discomfort/diffulcty when urinating
pollakuria - frequent abnormal urination
periuria - urination at inappropriate sites
anuria - failure of urine production by kidneys
oliguria - reduction in urine production
polyuria - increased urine production
stranguria
dogs - bacterial cystitis/urethritis, urinary calculi
cats - idiotpathic cystitis (stress) urolithiasis
if bladder large then bad
bladder inflammation - small bladder, thick wall, small squeeze elicits urination
bladder atony/lower motor neuron disease - large flaccid bladder, gentle squeeze elicits urination
obstruction - large tense bladder, urine not easily expressed
calcuil or mass - irregular hard masses felt, may have grating feeling
hematuria
trauma
rodenticides
genital sources
coagulopathies - bleeding from other sites
initial hematuria - lower UT
terminal hematuria - upper UT
total hematuria - upper UT, diffuse bladder disease, prostate or proximal urethra, coagulopathies
differentiate from hemoglobinuria and myoglobinuria
methods of urine collection
free catch - easy, owner can do, non traumatic or invasive, but risk of non-complicance, contamination, variable volume, risk of damage if manual expression
cystocentesis - quick, easy in cats, aseptic (culture), lower risk of infection than catheter, but a bit harder, may cause haemorrhage - contraindicated in severe bladder disease or coagulopathy
catheter - low bacterial contamination, big sample, but harder to do, risk of infection, not for culture because lower UT contamination. difficult in female cat - blind insertion
urinalysis artefacts
crystals - calcium oxalate, struvite
refrigeration artefacts - in vitro crystal formation, inhibition of enzyme reactions, falsely increased USG
room temperature artfacts - bacteria - overgrowth, metabolised chemicals, altered culture results
urine collection timing
early morning most concentrated (expect higher USG)
highest yield of cells
cells may be altered because of prolonged exposure to pH and osmolarity of urine (sitting in bladder longer)
glucouria may be more prominant post prandial
urinalysis - areas assessed
USG - loop of henle and distal tubule
dipstick - proximal tubules and grlomerular function
biochem - glomerular function
normal USG
dog - 1.015 - 1.045
cat - 1.045 - 1.060
in light of hydration -
isothenuria - 1.008 - 1.012
hyposthenuria - <1.008
well concentrated - >1.030
normal pH
high - >7.5 - UTI with urease producing bacteria –> metabolic alkalosis (but normal in herbivores)
low - <7 - UTI with acid producing bacteria –> metabolic acidosis (normal in carnivores)
crystalluria
precipitate when urine saturated with dissolved minerals
may get without disease
prolonged storage or cold artefact
magnesium ammonium phosphate - struvite - UTI or diet
cystine - hexagonal - abnormal, proximal tubular defect in amino acid transport
calcium oxalate dihydrate - envelope shape - acidic urine, urolithiasis, hypercalcuria, hyperoxaluria
calcium oxalate monohydrate - picket fence - ethylene glycol ingestion (may be normal in horses)
calcium carbonate - yellow brown crystals, alkaline urine - common in horses
bilirubin - orange-reddish brown - routinely seen in low numbers in dogs, abnormal in cats
ammonium biurate crystals - routine in dalmatians
renal tubular casts
proteinaceous plugs of dense mesh like mucoprotein
accumulate in distal nephron
normal in low numbers
increased - tubular disease
epithelial cells of UT
Transitional - renal pelvis, bladder, ureter, proximal 2/3 urethra
squamous - distal 1/3 urethra
pyuria
high leukocyte count
uroliths
calculus in urinary tract
usually calcium carbonate in horses and rabbits
ammonium sulphate or calcium oxalate in dogs and cats
bladder - cystolith
lower UT signs - dysuria, pollakuria, hematuria
may be palpable
ureters - uretoerolith
renomegaly and failure if bilateral
kidney - nephrolith
incidental usually
may have pyleophritis, pain, pyuria, pyrexia
urethra - urethrolith
lower UT signs
abdominal discomfort
licking
most severe - obstruction –> post renal azotemia –> acute kidney injury –> uremia
urethra palpable per rectum
urolith diagnosis
palpation
radiograph -
radiopaque - struvite, calcium oxalate, calcium phsphate
radiolucent - ammonium urate, cystine
ultrasound - easy to miss them
emergency treatment - urinary obstruction
emergency unless only partial
stabilise - manage hyperkalemia, fluid therapy
retrograde hydorpropuslsion - push stones backwards with catheter
urethrostomy - for recurrent problems
blood volumes
dog - 88ml/kg
cat - 66ml/kg
aims of fluid therapy
maintenance of normal physiology
improvement of organ function
correction of electrolyte disturbances
corretion of hypovolemia
correction of acid base disturbances
maintenance fluid rate
2.5ml/kg/hour = 60ml/kg/day
estimating fluid losses
no signs - <5% deficit
tacky mm - 5-6%
skin tent, sunken eyes - 6-8%
increased pulse, cold peripheries - 8-10%
weak pulses - 10-12%
collapse - 12-15%
types of fluid
CRYSTALLOIDS
isotonic - lactated ringers
shock, diruesis, anaesthesia, maintenance
hypotonic - sodium chloride
not used often
hypertonic - saline
drains water from interstitial space
restoration of BP, increased myocardial contractility, CO and oxygen delivery
large animals mostly
COLLOIDS
hetastarch
supports circulating blood volume
severe hypovolemia
more rapid initial re-expansion of volume and supports circulation longer than colloids, but no evidence actually better
BLOOD PRODUCTS
whole blood, packed RBCs, fresh frozen plasma, cryoprecipitate
