Hydration Flashcards
What is the most important nutrient?
H2O
What is the consequence of water deficiency? What is it called?
Can be fatal much sooner than any other nutritional deficiency. It is called dehydration
What determines an animals water requirements?
Species, Activity, and ambient temperature
What percentage of the body is water? What can change the water percentage?
60% of the body is water ( may change with age, nutritional status, hydration)
When is there water loss in the body?
Normal physiologic activities.
What are the steps to water intake regulation?
• INCREASED OSMOLARITY IN THE BLOOD -> OSMORECEPTORS THAT STIMULATE
THE HYPOTHALAMUS DIRECTLY OR THROUGH RELEASE OF ANGIOTENSIN II • THE RENIN–ANGIOTENSIN SYSTEM INCREASES THIRST AS A WAY TO INCREASE
BLOOD VOLUME
• ACTIVATED BY HIGH PLASMA OSMOLARITY, LOW BLOOD VOLUME, LOW BLOOD
PRESSURE, AND STIMULATION OF THE SYMPATHETIC NERVOUS SYSTEM
• THE ANTIDIURETIC HORMONE (ADH) IS IMPORTANT TO CONSERVE WATER IN
THE FACE OF DEHYDRATION
• A LACK OF RESPONSE TO ADH IN THE TUBULES, WOULD LEAD TO DILUTE URINE
AND DEHYDRATION
What is ADH?
Antidiuretic hormone
What is the function of ADH? What occurs in the absence of ADH? What is a condition that can cause Absence of ADH or resistance of ADH?
• ACTS TO INCREASE THE PERMEABILITY IN THE TUBULAR CELLS SO THAT
WATER IS ABSORBED AS THE INTERSTITIAL OSMOLALITY IS HIGHER THAN THE
FILTRATE • IN THE ABSENCE OF ADH (CENTRAL DIABETES INSIPIDUS) OR IF THE TUBULES
ARE RESISTANT TO ADH (NEPHROGENIC DI) URINE WILL BE DILUTE
What is the result of high sodium on plasma osmolarity?
It results in high plasma osmolarity.
What occurs to blood volume with high sodium and increased plasma osmolarity?
• THIS INCREASES BLOOD VOLUME AS
FLUIDS SHIFTS EXTRA CELLULARLY • IT ALSO CONTRIBUTES TO THIRST AND
ACTIVATION OF THE HYPOTHALAMUS • CAN CAUSE INCREASED BLOOD
PRESSURE
What is the formula for Water requirements for dogs?
Dog: 70 x Bw(kg)^0.75 Alternate formula ( 132 x Bw (kg)0.75 per 24 hours
What is the formula for water requirements for cats?
Cat: 70 x Bw(kg)^0.75
Alternate: 80xBW(kg)^0.75
What is the water requirement for a horse?
HORSE:0.3-0.8 GALLONS/100LB/DAY OR 25-70 ml kg/day
What is the avian water requirement?
AVIAN: 2 ML/KG/HR
OR 48 ML/KG/DAY
What is the reptile daily water requirement?
~2.5–3.5% OF BODY WEIGHT ON A DAILY BASIS
What determines cattle daily water requirements?
Age and production
What is the daily water requirement for dry cows?
24-49 L/day
What is the daily water requirement for a dairy calf between 1-4 months of age?
4.9-13.9 L/ day
What is the daily water requirement for a dairy heifer (5-24 months)?
~14.4-36.3 L/ Day
What is the main clinical intervention that could be provided for a patient who is dehydrated?
Rehydration
What are some consequences of dehydration?
- Poor perfusion
- Electrolyte disturbances
- Acid base disturbance
- endothelial injury
- inflammation
- coagulapathy
What degree of dehydration will the patient begin to exhibit clinical signs of dehydration?
5%
What are indicators of dehydration you can see on a physical exam?
- Change in body weight
- Mucus membrane character
- CRT
- Skin Turgor
- Heart Rate
- Respiratory Rate
- Pulse quality
- Urine output
- Blood pressure
What are some other indications of dehydration in diagnostic testing?
- PVC/TS
- Decreased size of Vena cava on Radiographs ** Severe dehydration
- USG
- Lactate
- BUN/Creat
- Osmolality
What is the typical specific gravity range for cats?
1.030-1.050 (as per Stockman)
Book says 1.020-1.040
What is the urine volume typically produced daily for a cat?
10-20 ml/kg/day
What is the typical specific gravity of a cow?
1.030-1.045
What is the urine volume typically produced daily for a cow?
17-45 ml/kg/day
What is the typical urine output per day for a dog?
20-100 ml/kg/day
What is the urine volume typically produced daily for a dog?
1.020-1.060 ( Stockmans)
Book: 1.016-1.060
What is the normal specific gravity range for a goat?
1.015-1.045
What is the normal daily urine output for a goat?
10-40 ml/kg/day
What is the normal specific gravity range for a horse?
1.025-1.060
What is the normal urine output for a horse per day
3-18 ml/kg/day
What is the normal specific gravity range for a pig?
1.010-1.050
What is the normal urine output of pigs?
5-30 ml/kg/hr
What is the normal urine output of sheep?
10-40 ml/kg/hr
What is the normal specific gravity of sheeps urine?
1.015-1.045
What ways can water be provided to the patient?
- ORALLY (PO)
- INTRAVENOUSLY (IV)
- SUBCUTANEOUSLY (SQ)
- INTRAOSSEOUS (IO)
What kind of fluids can be provided parentally to the patient
FLUIDS MAY BE ISOTONIC
(MOST COMMON),
HYPERTONIC OR
HYPOTONIC (SPECIFIC
INDICATIONS)
What is the proper way to administer fluids?
ALL NEED TO BE STERILE, AND ADMINISTERED ASEPTICALLY.
What substances can be in parental fluids?
May provide water, electrolytes, glucose and sometimes, vitamins.
What are crystalloid fluids?
Clear fluids
- No lipids/ protein
- Saline (0.9% NaCl)
- LRS Solution
What are colloid fluids?
Provide osmotic substance such as starch, albumin, gelatin
What is important about monitoring patients while they are receiving fluids?
• PATIENTS ON IV FLUIDS SHOULD
BE MONITORED TO ENSURE
THEIR REHYDRATION IS
PROGRESSING AT AN
ACCEPTABLE PACE.
What monitoring should be included when monitoring a patient on IVF?
• CLINICAL SIGNS OF DEHYDRATION
• TPR • BODYWEIGHT
• IF POSSIBLE- URINE PRODUCTION AND URINE
SPECIFIC GRAVITY
• AUSCULTATION
• MUCUS MEMBRANE COLOR
• PCV/TS
• BLOOD PRESSURE
What can occur with overhydration?
- OVERHYDRATION IS MOST OFTEN IATROGENIC
• CAUSED BY EXCESSIVE IV FLUID ADMINISTRATION
• CAN BE EVEN MORE DETRIMENTAL THAN DEHYDRATION
What clinical signs can be seen with over hydration?
- RESPIRATORY DIFFICULTIES
- LUNG EDEMA
- PITTING EDEMA
- CONFUSION/SEIZURES
- HIGH BP, TACHYCARDIA
- EXCESSIVE MUCUS MEMBRANE MOISTURE
What are the tests that can be done for overhydration?
Radiographs
What are the treatments for overhydration?
- D/C FLUIDS • DIURETICS • OXYGEN
What percent of moisture is found in dry food?
10% moisture
What percent of moisture is found in canned food?
80% moisture
How do you calculate the water needed for a patient with a feeding tube?
1 ml/ 1 kcal consumed. Water should be added up to total per day and subtract what you are using to flush the tube and make the slurry.
What is one concern for a patient who is dehydrated?
Increased risk of overheating. Water loss in urine and evaporation is accelerated with exercise.
What is a body temperature that is concerning and potentially dangerous? What organs can be affected?
Body temperature > 104.
Intestines and kidneys are susceptible.
Can you use/ is their benefit to using hydration drinks in veterinary medicine?
DEPENDS ON THE SPECIES
• HYDRATION DRINKS (W/ELECTROLYTES) ARE NOT USEFUL IN ANIMALS THAT
DO NOT SWEAT
What is the concern with increased drinking and urination?
- POLYURIA AND POLYDIPSIA (PU/PD) IS AN IMPORTANT CLINICAL SIGN IN SEVERAL DISEASES
- IT CAN ALSO INCREASE THE RISK FOR DEHYDRATION
- THIS CAN BE THE RESULT OF PRIMARY POLYDIPSIA OR A DECREASE IN THE RENAL ABILITY TO CONCENTRATE URINE (FOR A VARIETY OF REASONS) WHICH RESULTS IN INCREASED WATER INTAKE
What is an example of tests done for a workup of PU/PD?
WOULD INCLUDE A URINALYSIS (URINE TEST) AS A FIRST-TIER TEST
( Urine can be free catch unless, being also sent for culture.)
What is Isosthenuria?
USG of ~ 1.008- 1.012
What is Hyposthenuria?
USG Lower than 1.008
What would be indicated in test results with urine that is adequately concentrated and has no glucose?
LIKELY BEHAVIORAL, CYSTITIS, BLADDER MASS, UROLITHIASIS, ANATOMIC/
NEUROLOGIC
What would be indicated in test results with urine that is concentrated and has glucose?
POSSIBLE DIABETES MELLITUS (EARLY) OR PRIMARY RENAL GLYCOSURIA (RARE)
What would be indicated in test results with urine that has a low USG?
RENAL DISEASE, PYOMETRA, HYPERCALCEMIA, LIVER DISEASE, CUSHING’S DISEASE, ADDISON’S DISEASE, HYPERTHYROIDISM
