Lecture 6 - Water

Question 1

Species, activity level, and ambient temperature all affect…

Answer 1

Water requirements

Question 2

Up to _____% of the body is water, but this may change with age, hydration, and nutritional status

Answer 2

60

Question 3

True or False: Water is needed to replenish fluids lost during normal physiological activities

Answer 3

True

Question 4

What does increased osmolarity in the blood activate?

Answer 4

Osmoreceptors that stimulate the hypothalamus (directly or through release of angiotensin II)

Question 5

A system that increases thirst as a way to increase blood volume

Answer 5

Renin-Angiotensin system

Question 6

What are some factors that activate the renin-angiotensin system?

Answer 6

High plasma osmolarity, low blood volume, low BP, and stimulation of sympathetic nervous system

Question 7

Which hormone is important to water conservation during periods of dehydration?

Answer 7

Antidiuretic hormone (ADH)

Question 8

What will occur if there is a lack of response to ADH in the renal tubules?

Answer 8

Dilute urine and dehydration

Question 9

ADH is secreted by the __________ gland

Answer 9

Pituitary

Question 10

ADH acts to _______ the permeability in the tubular cells so that water is absorbed as the interstitial osmolarity is ______ than the filtrate

Answer 10

Increase; higher

Question 11

Central Diabetes Insipidus is characterized by…

Answer 11

Absence of ADH (resulting in dilute urine)

Question 12

Nephrogenic DI is characterized by…

Answer 12

Tubules being resistant to ADH (resulting in dilute urine)

Question 13

True or False: High sodium = decreased plasma osmolarity

Answer 13

False; High sodium = INCREASED plasma osmolarity

Question 14

Why does blood volume (and sometimes BP) increase when sodium/plasma osmolarity is high in the body?

Answer 14

Fluids are shifting extracellularly

Question 15

Poor perfusion, electrolyte disturbance, acid-base disturbance, endothelial injury, inflammation, and coagulopathy are all possible consequences of…

Answer 15

Dehydration

Question 16

Clinical signs of dehydration may not be evident until a patient is at least ___% dehydrated

Answer 16

5

Question 17

List some clinical/diagnostic indicators of dehydration

Answer 17

Dry MM, longer CRT (>2), skin turgor w/ low elasticity, inc HR, inc resp rate, weak pulses (low BP), low urine output, high PCV/TS, high USG, high lactate, high BUN/CREAT, high osmolarity

Question 18

What are four ways fluids can be provided to patients?

Answer 18

Orally (PO), intravenously (IV), subcutaneously (SQ), and intraosseously (IO)

Question 19

True or False: Parenterally provided fluids can be isotonic, hypertonic, or hypotonic

Answer 19

True (though isotonic is most common)

Question 20

True or False: Parenteral fluids do not need to be administered sterilely

Answer 20

False; they must be administered sterilely/aseptically to avoid infection

Question 21

What are crystalloid fluids?

Answer 21

Clear fluids w/o lipids or proteins

Examples: saline (0.9% NaCl) and LRS

Question 22

What are colloid fluids?

Answer 22

Fluids which provide osmotic substance such as starch, albumin, and gelatin

Question 23

True or False: Patients on IVF should be monitored to ensure rehydration is progressing at a steady pace

Answer 23

True

Question 24

List some important factors to monitor during rehydration

Answer 24

Changes in clinical signs of dehydration, TPR, body weight, urine production/USG, auscultation, MM color, PCV/TS, BP

Question 25

What is overhydration?

Answer 25

Excessive hydration, most often iatrogenic and caused by excessive IVF administration

Question 26

How is overhydration diagnosed?

Answer 26

Resp difficulties, lung edema, pitting edema, confusion/seizures, high BP, tachycardia, excessive MM moisture

Question 27

How is overhydration treated?

Answer 27

D/C fluids, diuretics, O2

Question 28

True or False: Patients with feeding tubes never need supplemental hydration with regular water

Answer 28

False; some may require water through the feeding tube, roughly calculated at 1 ml per 1 kcal

Question 29

Which two organs are most susceptible to damage from overheating?

Answer 29

Kidneys and intestines

Question 30

Dehydration ___________ the risk for overheating

Answer 30

Increases

Question 31

What is generally considered a very high and dangerous body temperature?

Answer 31

Anything >104 degrees F

Question 32

True or False: Drinks with electrolytes are only beneficial to animals who sweat, and will not help animals who do not sweat

Answer 32

True

Question 33

What are the clinical names for increased drinking and increased urination?

Answer 33

Polydipsia and polyuria

Question 34

What would be an important initial diagnostic test for a patient exhibiting PU/PD

Answer 34

Urinalysis

Question 35

What is the numerical range for normal urine concentration (USG)?

Answer 35

1.025 to 1.035

Question 36

What USG range is indicative of urine that is NOT concentrated (isosthenuria)?

Answer 36

1.008 to 1.012

Question 37

Hyposthenuria refers to a urine concentration that is less than…

Answer 37

1.008

Question 38

If urine is adequately concentrated and contains no glucose, but a patient is still exhibiting PU/PD, what are some possible causes?

Answer 38

Behavioral, cystitis, bladder mass, urolithiasis, anatomic/neurologic

Question 39

When urine is concentrated with glucose, what are two possible medical conditions that could be the cause?

Answer 39

Diabetes mellitus (early) or primary renal glycosuria (rare)

Question 40

Renal disease, pyometra, hypercalcemia, liver disease, Cushing’s disease, Addison’s disease, and hyperthyroidism are all medical conditions associated with…

Answer 40

Low urine specific gravity