Lab Exam 1 Flashcards
What are crystalloids?
Salt or sugar solutions without large molecules which allow them to readily cross endothelium
What is an example of a salt cystalloid?
NaCl or LRS
What is an example of a sugar crystalloid?
D5W
What are colloids?
Natural or synthetic fluids that contain large molecules that can not cross endothelium
What do colloids do?
Contribute to oncotic pressure within the vascular space so it draws fluid into the vessel
What is shock?
Decreased delivery of fuel/oxygen at the cellular level, which if it persists can cause irreversible injury to cells
What areas of the body are most affected by shock?
The heart, blood and cells
What are the different types of shock?
- Hypovolemic- Cardiogenic- Obstructive- Distributive
What is hypovolemic shock?
Reduced circulation of blood volume in relation to total vascular capacity
What is the most common type of hypovolemic shock?
Blood loss, but it’s not always the main reason for this condition
What is cardiogenic shock?
A pump failure due to loss of contractility and/or functional myocardium
What is SVR?
Systemic vascular resistance meaning the vessels are trying to constrict to compensate for loss and increase pressure
How does cardiogenic shock effect afterload and fluid retention in the body?
It increases afterload with angiotension and increases fluid retention with aldosterone
How would you treat cardiogenic shock?
Optimize cardiac function and treat with diuretics such as Lasix (furosamide) NO FLUIDS
What is obstructive shock?
Impaired venous return such as tension pneumothorax, pericardial tamponade, or GDV
What is distributive shock?
Loss of vasomotor control
What three forms of shock are characterized by tachycardia and increased SVR?
Hypovolemic, cardiogenic, and obstructive
How is distributive shock characterized?
Tachycardia, decreased SVR, warm extremities and bounding pulses
Which form of shock should NOT be treated with fluid therapy?
Cardiogenic, and it should be used carefully in obstructive shock as not to overflow the patient which will result in an increased afterload
What are the three phases in the treatment of shock?
- Phase One: Resuscitation - Phase Two - Rehydration - Phase Three - Maintenance
How much fluids should be administered based on weight loss?
- 1 g = 1 ml- 1 kg = 1 L
What is the formula for maintenance fluid replacement?
66 ml/kg/24 hr
Which fluid is best to treat shock?
Colloids because they decrease oncotic pressure, and help acute blood loos
What is the colloid dose for shock fluid therapy?
- Dog: 20 ml/kg/hr- Cat: 10-20 ml/kg/hr
Which fluid is best to treat a dehydrated patient?
Crystalloids because they rehydrate the tissues not the vessels
What is the crystalloid dose for shock fluid therapy?
- Dog: 80-90 ml/kg/hr- Cat: 40-60 ml/kg/hr
How do you determine the rehydration rate of fluids?
- % dehydration/100 x bw in kg = L of deficit- L of deficit x 100 = ml of deficit - ml of deficit/24 hr = ml/hr rehydration rate
What are the clinical signs of a lower urinary tract infection?
- Frequency- Inappropriate urination or incontinence- Stranguria- Hematuria
What is pollakuria?
Increase in the frequency of urination
What is stranguria?
Straining to urinate
What is hematuria?
Blood in the urine
When is the best voided sample for urination collected?
Midstream to avoid bacterial or cell contamination
What is the least preferred method of urine collection?
Manual expression due to possible blood contamination from applying manual pressure to the bladder
How is the most sterile urine sample collected?
Cystocentesis
What are some risks when performing a cauterization to collect a urine sample?
It can result in a bacterial infection from catheterization or rupture of the urinary tract
When is it most acceptable to use a urinary catheter to obtain a sample?
In cats because they have the least amount of bacteria in their ureter
How soon after obtaining a urine sample should a U/A be performed?
Within 30 minutes, otherwise sample should be refrigerated
What are some possible outcomes of a delayed analysis?
- Bacterial contamination- Altered pH- Disrupted or disolved crystals- Cellular detailed loss especially with WBC and epithelial cells- Chemical precipitation- Crystal formation
What are the parts of a urinalysis?
- Physical properties (SG)- Chemical properties (dip stick)- Sediment examination
What are the physical properties identified in a U/A?
- Color- Transparency- Odor- Foam- Specific Gravity
What animal may have myoglobinuria present if a sample is left to sit for 24 hours?
Horses
What is flocculence?
Particles floating in a urine sample
Which animals may have cloudy urine?
Horses and rabbits due to naturally occurring calcium carbonate crystals
What is isothenuric?
- When the specific gravity is the same concentration as plasma, meaning the kidneys are not working well- 1.008 - 1.012
What is hypothenuric?
- Specific gravity is less concentration of plasma- < 1.008
What is hyperthenuric?
- Specific gravity concentration is greater than that of plasma and is the ideal normal for kidneys- > 1.012
What are the normal specific gravity values of animals?
- Dogs: 1.015 - 1.045- Cats: 1.035 - 1.060- Large animals: 1.015 - 1.030
What does a higher than normal specific gravity number indicate?
The urine is more concentrated and the animal may be dehydrated
What does a lower than normal specific gravity number indicate?
The animal’s kidneys may be having trouble concentrating urine
What are the common chemical properties of urine?
- pH- Protein- Occult blood- Glucose- Bilirubin- Ketones- WBC- Nitrites
What should the pH of a carnivore be?
More acidic (0-6) due to higher amino acid
What should the pH of a herbivore be?
More basic/alkaline (8-14) due to more carbohydrates
What is the pH commonly of an omnivore?
It is dependent of what they ate prior to analysis
When may it be normal to see glucose in a urine sample?
If an animal may have eaten prior to analysis
What is the abnormal amount of blood glucose in a dog?
180 mg/dl
What is the abnormal amount of blood glucose in a cat?
280 mg/dl
Is protein and/or bilirubin present in a urine sample considered normal for a cat or dog?
Small trace amounts maybe be seen in a dog’s sample, but a cat should never have protein or bilirubin in their urine
What are ketones in a urine sample indicative of?
The breakdown of fat which may be a result of diabetic ketoacidosis
What is the desirable amount for a U/A?
5 ml
What may be seen in a sediment examination of a urine sample?
- RBC and WBC- Epithelial cells- Microorganisms- Crystals- Other elements
What type of epithelial cells may be present in a sediment examination?
- Squamous- Transitional- Caudate- Renal
Where are urine casts formed?
- In the renal tubules; stage of cast seen may determine the stage of renal disease the animal is in- Hyaline, WBC, RBC, renal tubular, epithelial, course granular, fine granular, waxy
What are some reasons for a blood chemistry panel?
Diagnose, monitor and screen possible diseases
What is the A/G ratio on a chemistry panel?
Albumin to globulin ratio
What is CPK on a chemistry panel?
Creatinine phosphokinase a muscle enzyme
What are some variables that can affect a chemistry panel?
- Pre-analytical which can occur before running a test- Analytical which occur while the test is running- Post-analytical which occurs after the test has been complete
What are some pre-analytical biologic variables?
- Inherent patient variables such as species, breed, age, and gender - Controllable patient variables such as recent food ingestion, stress which releases cortisol and epinephrine, and exercise
What are some pre-analytical non-biologic variables?
Sample collection and handling
What are some analytical variables?
- Interference - Assay performance
What kinds of interference can occur with analytical variables?
- Lipemia which can lead to volume displacement- Hemolysis- Icterus - Hyperproteinemia- Drugs
What are the post-analytical variables that can affect reference ranges?
- Human error- Variations from one lab to another
What determines the reference ranges of a testing panel?
Usually determined from a population of healthy adult animals
What is another name for Gaussian Distribution?
The Bell Curve
What is the acceptance area of a bell curve?
Covers about 95% of the population
What is the rejection area of a bell curve?
It makes up 2.5% on the high end and low end because accepted ranges are determined by humans, therefore about 5% of normal animals may fall out of range
What is concentration?
The amount of solute contained in a certain amount of a solution
T/F: Concentration is a variable property
True
How can concentration of solutions be expressed?
- Volume percent- Weight percent- Weight/volume percent
What is the formula for determining volume percent?
Volume of solute/volume of solution x 100 = volume percent
What is the formula for determining weight percent?
Weight of solute/weight of solution x 100 = weight solution
What is the formula for determining weight/volume percent?
Weight of solutes (g)/volume of solution (ml) x 100 = weight/volume percent
What is colorimetry?
As light passes through a solution, light of a certain wavelength is absorbed by the colored chemical
What is the amount of light absorbed by a chemical directly proportional to?
- The concentration of the chemical that the light passes through- The thickness, or path length, of the solution
What is Beer’s Law?
- A: absorbance - I: intensity of transmitted light- Io: intensity of incident light
What ways can concentration be determined?
- Beer’s law- Proportionality- Graphing
