Micturition and Urinalysis Flashcards
what aninakls secrtee calcium carbonate in urine?
horses, hamsters
problem with calcium carbonate being excreted in urine?
crystals can build up so horses produce mucus - so urine is slightly thicker
where does the ureter enter?
enters at proximal angles of bladder trigone
oblique path of ureter against bladder wall creates?
creates valve like entry
reduces urinary reflux and damage
bladder walls?
layers of smooth muscle layers in the walls
rugae of the bladder?
stretches of the transitional epithelium lining (internal layer) allows capacity increase
reduce back-pressure on the kidney - maintain GFR
bladder neck has?
it has thickened musculature - IUS
striated fibres of the bladder create?
create the EUS and is under voluntary control
which nervous system innervates the bladder?
autonomic nervous system
what nerve endings does the bladder wall have?
it has stretch-sensitive nerve endings
position of the bladder upon examination is dependent on?
how full it is
bladder entry where?
through detrusor muscle in bladder trigone
contractions of the muscle cells in the wall of the renal pelvis do what?
it forces urine produced out to the ureters into the bladder which allows the bladder to slowly fill up as there is no sphincter
as bladder fills up and pressure increases - what happens to ureters?
they get compressed at the point they enter bladder
what does the IUS do?
it keeps urethral opening closed as long as pressure in bladder is not high
when bladder fills what is stimulated?
stimulates stretch nerve endings - due time, detrusor muscle contracts
what are the two positive feedback mechanisms for bladder emptying?
- detrusor contracts, pressure in bladder increases, IUS opens, more tension at neck of bladder - stops the contraction of EUS
- urine flow stimulates sensory cells in urethra, increases activity of parasympathetic fibres to detrusor muscle –> to increase contraction
what is the main function of renal autoregulation?
prevent too many changes to the filtration rate
what positive feedback process takes place after urine starts to be voided?
increases activity in the parasympathetic fibres to the detrusor muscle - causes the bladder to empty fully
In newborn and untrained animals - urination is largely what type of reflex?
a spinal reflex
if the bladder gets too full, what happens to control?
cerebral control gets overridden if the bladder gets too full
provocation of urination?
large animals - whistling, stimulation of vulva
ruminants - stress induced urination - very common
small animal - trans-abdominal compression
for urinalysis - what to look for?
assessment of colour and turbidity (cloudiness)
measurement of specific gravity (conc)
measurement of pH (acidity) and chemical components
Microscopic examination of the cells and sediments
species variation for appearance of urine: rabbits, horses, guineas?
they have naturally occurring cloudy urine
species variation for appearance of urine: rabbits, guineas?
can be discoloured but is still normal
what can cause discolouration of urine?
diet, stress, dehydration can cause discolouration e.g. beetroot, carrots
more dilute urine?
lower the number for measure of specific gravity
urine collection techniques?
free catch
manual expression
catheterisation
cystocentesis
problems with free catch strategy?
different species - variation? storage? midstream, clean?
problems with manual expression strategy?
safety? blockage? gender? possibility for contamination with debris
problems with catheterisation strategy?
sedation? contamination? blockage? potential contamination as well
JUST USE FINGERS DO NOT USE FORCEPS
problems with cystocentesis strategy?
sedation? safety? clean?
ram blocked?
same as tom cat treatment
free catch sample?
let the owner collect as the animal urinates
sometimes microbial growth can occur and increased risk of contamination
cystocentesis?
stick needle into bladder and get urine, this is sterile - however possible blood contamination
put needle in as close to body or sphincter end as bladder is less likely to contract off of the needle and create a bigger gap
Dipstick analysis?
using urine strip, dip w/ pipet or dip into urine specimen
test pathological colour changes vs normal colour change
read results based on the colour
urine specific gravity is measured using a?
using a refractometer
what does urine specific gravity evaluate?
it evaluates renal function by assessing whether water is being excreted or conserved appropriately, according to need
what does urine specific gravity provide an approximate guide to?
to urinary solute concentration that is sufficiently accurate for clinical purposes
to know if concentration is inappropriate, what do you need to know?
need to know hydration status
concentrated urine?
USG > 1.030 (dog) or >1.035 (cat)
dilute urine?
USG < 1.008
moderately concentrated urine?
USG 1.013 to 1.029 (dog) or 1.034 (cat)
inappropriately dilute urine:
USG < 1.030 (dog) or <1.035 (cat) in a dehydrated animal
Isosthenuria?
USG 1.008 to 1.012
microscopy examination of urine?
observe urine under a microscope to examine cells and crystals
sedimentation will produce better finding
potentially able to identify type of bladder calculi based on type of crystal
staining can be used to assist with making things clearer / always look first before staining
