Unit #1: Urine General

What happens when bladder is full?

Stretch receptors let the brain know it’s time to urinate

What type of cells is the bladdar made of?

Transitional epithelial cells, which allow it to stretch a

Where are the nerves that are responsible for the bladder stretch receptors located?

s1-s3

Which nerves are responsible for the bladder neck/ proximal urethra

L7-S3

What can happen if an animal cannot urinate?

Bladder may stretch and burst

Urine may back up into kidneys

WHat differs in the anatomy of the bladder between male and female animals?

Males have a C-shaped flexure of the penis that affects the bladder's positioning, while females have a more vertical urethra.

Name the 4 urine collection methods

1. Free catch/voided

2. Manual Expression

3. Cystocentesis

4. Catheterization

When is the bladder most commonly manually expressed?

Before surgery (especially OVH) because full bladder can hinder in visualization

What is the general opinion on manual expression of the bladder in healthy animals?

Contraindicated (should not be done)

Note: especially with a history of bladder trauma

List manual expression complications

• bleeding into the bladder due to aggressive technique

• Rupture of bladder

Male dogs need sedation for urinary catheter placement?

Generally no but case dependent (PVPs recommended)

Female dogs/ M and F cats need sedation for urinary catheter placement?

Yes

What material would be used for an indwelling urinary catheter?

Silastic (silicone/ plastic)

When would we use a urethral catheter

• obtaining urine sample

• Drain bladder if abnormally distended

• animal cannot urinate normally (neurological deficit)

• Dislodge obstruction (stone or calculi)

• Monitor urine production (indwelling)

• Maintain constant drainage (indwelling)

• Post bladder surgery

• Post blockage

Urethral Catheterization Complications?

• trauma to urethral/bladder

• hematuria

• use of a non-sterile catheter

• forces contaminants from distal third of urethra into bladder

• infection of prepuce/vagina introduced into bladder

• length of time catheter in place (indwelling)

Should we do a cysto if we suspect a bladder mass?

No

Complications of cystocentesis

• minor/major laceration

• hematuria

• peritonitis (inflammation of the peritoneum, typically caused by bacterial infection either via the blood or after rupture of an abdominal organ.)

• surrounding abdominal organs

List different catheter varieties for different occasions

•Is it for a dog or cat or horse?

•Is it going to stay in for awhile?

•Is the animal male or female?

•Does the catheter need to be hard to bypass something?

•Once you have answered these questions, you can choose a catheter....

What type of material for urethral catheter for dog?

•Polypropylene (plastic)

What to do before placing catheter?

Premeasure catheter

Where does catheter need to go?

Around ischial arch- urethra to bladder

What material are cat catheters made of?

Polypropylene

What catheters are specifically designed for cats?

Mila Urinary Catheters (comfortable and easy to pass)

List equipment for catheterization

• sterile catheter

• sterile lube

• antibacterial scrub

• bowl of warm water/sponges

• betadine solution

• syringe for urine collection

• sterile exam gloves- optional

What are the two techniques for female dog catheterization?

1. Digital

2. Visualization

List steps for digital method

• gather supplies

• wash hands

• retrain patient

• clip long hair around vulva

• scrub vulva with antibac sopa three times and rinse with water

• Open cather package and apply small a mount of xylocaine jelly

• wash hands and put on sterile gloves

• lubricate finger of “off” hand and insert into vagina

• insert dorsal then cranial to second knuckle

• pass catheter under finger, guiding down into urethra

• do not let it go past your finger or it is still in vagina

• advance catheter until urine is observed- approx 6-12 cm

• attach sterile syringe- discard first 2-3 mls (bacteria contamination)

• attach a second syringe and collect sample (6mls)

What are 4 pieces of equipment that a urinalysis requires ?

1. Collection vessel

2. Centrifuge

3. Test strips

4. Microscope

What are 3 body systems that urinalysis evaluates?

• bladder

• Kidneys

• Disease

What are the 3 collection methods?

1. Free catch/voided

2. Catheter

3. Cysto

List 4 advantages of free catch

1. Low cost

2. No risk to animal

3. If blood present- not due to collection method

4. Easy

List 4 free catch disadvantages

• Bacteria can contaminate sample (fur, prepuce, vulva)

• Human error

• Must be run right away (crystals can go out if not analyzed in 30min)

• Falsely concentrated USG if sample sits over night

List 3 advantages to a catheterized sample

• can be performed without sedation

• Can be used for culture

• Tests patency of urethra

List 3 disadvantages of catheterized samples

• Requires training (must be aseptic)

• Can cause accidental trauma and blood can contaminate sample

• Hard to catheterized females, and cats

List 3 Cysto advantages

• cleanest sample

• Only done by trained personnel

• Done by palpation or ultrasound guided

What does specific gravity relate to

Kidneys ability to concentrate urine

List 3 Cysto disadvantages

• may cause hematuria

• Risk hitting major vessels

• Vasovagal event

Why is first morning sample so important ?

Most concentrated

Determines patients ability to concentrate urine

True or False?

Pre-prandial sample will be your most acidic urine sample of the day (lowest pH)

True

T or F?

Cysto is the most sterile collection method

T

If analysis of the sample cannot be performed within 30 mins, what should you do?

Refrigerate, then bring to room temp prior to examination

What is “Polyuria”

• producing excessive amount of urine above what’s expected for that animal

If the patient has polyuria will it have a high or low USG?

Low

What is “Oliguria”?

• reduction in urine output

What is “Anuria”?

• no urine produced

• Critical

How many mls of urine must be collected to perform a urinealysis?

At least 5mls

What are the 4 main things observed upon macro analysis?

1. USG

2. Color

3. Transparency

4. Odour

What are the dog, cat, and horse/cow USG normal ranges?

Dog: > 1.030

Cat: > 1.035

Horses/cow: >1.025

What is the USG range for “isosthenuria”?

1.008 - 1.012

What is the range for “Hyposthenuria”?

< 1.008 active dilution

How much nephron damage does there have to be before you see the kidneys lose their ability to concentrate urine?

66% or 2/3

If the USG is high, will the urine color be darker or lighter?

Darker

If the urine color ranges from red-brown-black, what may be found in the urine?

• erythrocytes

• Hemoglobin

• Myoglobin

• Methemoglobin

If the urine color is ranging from yellow-orange-green-brown, what may this indicate is in the urine?

• bilirubin

• Biliverdin

T or F

Horses and rabbit have cloudy urine

T

What does flocculent mean when referring to the transparency of urine?

Particles are in the urine that are large enough to see with the naked eye

What do we use to perform a chemical analysis?

Reagent strips

List some things that reagent strips test for (10)

• leukocytes

• Nitrite

• Urobilinogen

• Protein

• PH

• Blood

• Specific gravity

• Ketones

• Bilirubin

• Glucose

What are the 4 things that are not accurate in reagent strips?

• USG

• Urobilinogen

• Nitrate

• Leukocytes

5 steps for using reagent strips

1. Mix urine

2. Briefly dip into sample

3. Tap edge on paper towel

4. Lay flat

5. Compare to color chart at specific time

Once reagent strip bottle is open, how long until they should be thrown out?

6 months

What are some causes of error for reagent strips? (5)

• keeping strip in urine for too long

• Too much urine running over between pads

• Not laying flat

• Reading too soon or late

• Poor light

What is pH

Measure of hydrogen ions in the urine

When would the pH be the highest

4hr PP

Urine protein : creatinine ratio

Dogs: <0.2 non proteinuric, 0.2-0.5 borderline proteinuria, >0.5 proteinuric

Cats: <0.2 non proteinuric, 0.2-0.4 borderline proteinuria, >0.4 proteinuric

Normal color of urine is do to presence of what

Urochromes

What does the ph on a regent strip measure

Hydrogen

Name 5 reasons for decreased USG

• renal disease

• Liver disease

• Endocrine disease

• Electrolyte/mineral imbalance

• Pupd

Name the four methods for urine collection?

1. Free Cath

2. Urinary Catheterization

3. Cystocentesis

4. Manual Expression

Name an Advantage and disadvantage for obtaining a free catch urine sample?

Advantage - Simplest sample to obtain, no risk to patient

Disadvantage-Sample is not good for bacteriologic examination, can pick up bacteria via fur, sample can be “left out and dries out”

Name an Advantage and disadvantage for obtaining a urine sample via urinary catheterization?

Advantage- Urine sample is sterile

Disadvantage-more difficult to perform in female animals

Name an Advantage and disadvantage for obtaining a urine sample via cystocentesis?

Advantage-gold standard for bacterial culture and sensitivity

Disadvantage- hematuria can occur

What should you do if the urine sample can’t be analyzed within 30mins of collection?

Refrigerate then bring to room temperature when ready to examine

What is the most ideal method to obtain a USG?

Using a refractometer

What are three things we can observe when doing a gross examination on a urine sample?

1. USG

2. Color

3. Transparency

What does the specific gravity often relate to?

kidneys ability to concentrate urine

Define the following: Oliguria

decrease urine output

Define Anuria

Complete lack of urine output

Define Polyuria

Production of excessive amounts of urine

Name two reasons for an increased USG?

• Decreased water intake or dehydration

• •Increased fluid loss through sources other than urination

Name two reasons for an decreased USG?

1. Renal disease

2. Liver disease

3. Endocrine disease: Hyperadrenocorticism, diabetes mellitus

4. Certain electrolyte or mineral imbalances

5.Polyuria+ Polydipsia

What colors of urine are considered normal?

Pale yellow, Yellow, dark yellow

The normal color of urine is due to the presence of what?

Urochromes

True or False can drugs alter the color of urine?

True- why accurate history taking is important.

What does reddish- brown urine indicate?

Hematuria or Hemoglobinuria

True or False Milky white urine is due to the presence of fats or purulent discharge

True

What does the presence of yellow-brown with greenish yellow urine

Presence of bile pigment

What are three transparencies or urine that we often report?

1. Clear

2. Cloudy

3. Flocculent

True or False: Reagent strips can be kept for over 6 months after the bottle is opened

False

What does the pH on the reagent strip measure?

Hydrogen ion (H+)

True or False pH is highly variable throughout the day

True

What are three reasons for an abnormal urine acidic pH

•Starvation

•Consumption of a high protein meal

•Conditions which relate to respiratory or metabolic acidosis

What are two reasons for an abnormal urine alkaline pH?

1. Infection of the urinary tract. UTI’s are a common reason why we may see an alkaline urine because of urease producing bacteria, which drive the urine pH up.

2. Respiratory or metabolic alkalosis

What are two ways to measure protein? How is each method tested?

1.Quantitative methods

(Some reference laboratories verify the results of a positive dipstick test using sulfosalicylic acid (SSA))

2. Semi-quantitative dipstick methods

(Reagent strip testing for protein utilizes the principle of the "protein error of indicators" to produce a visible colorimetric reaction.)

What is the most common error when measuring protein by the dipstick method?

Excessive time that the dipstick remains in the urine.

In a healthy individual proteinuria will be present in the urine?

False

True or False. False negatives will occur with outdated strips?

True

What are three reasons we may see glucosuria?

1. Diabetes mellitus

2. Stress glucosuria

3. Renal disease

True or False: Ketones are not normally completely reabsorbed by the proximal tubules of the kidney, so we are able to measure the presence of ketones on a reagent strip?

False They are completely reabsorbed in the tubules. Should not be present on the dipstick.

True or False: Urobilinogen measured by a dipstick is unreliable?

True

Is conjugated or unconjugated bilirubin found in the urine?

Conjugated bilirubin