Fluid therapy Flashcards
Most common reasons for dehydration
Diarrhea
Vomiting
Polyuria
Extensive wounds
Extensive sweating
Purpose of fluid therapy
- To compensate for loss of fluids
caused by pathology (dehydration) - To correct dehydration, electrolyte
and / or acid-base imbalance
Signs of dehydration
Skin is dry and wrinkled,
Eyes are sunken
Skin elasticity disappears
Low amounts of concentrated urine,
Thirst,
Oliguria
Fever
Dryness of mucous membranes
Constipation
Loss of body mass
Muscle tremors
Death
Physiological losses or retention of fluids
Urine output,
Evaporation from skin surface
Natural sweating
Evaporation from respiratory tract
Pathological losses of fluids
Vomiting and diarrhea
Hemorrhaging
Sweating and fever
How much does rise in body temperature by 1 degree above the normal level increase excretion of liquids (in humans)
by 500 ml per 24 hour period
What is meant by “third space losses”
Fluid shift within body;
- like in case of trauma,
- in event of surgery,
- in case of inflammatory bowel disease
(esps in horses)
So extravasation of fluid from vascular compartment into extravascular spaces
In case of strong and long-duration dehydration, how do we compensate for fluid losses?
By adding potassium into the isotonic solution in order to ensure the function of heart and skeletal muscles
In case of loss of blood, how do we compensate the fluid losses
By administering colloidal solutions, plasma substitutes.
Particles of high molecular weight absorb slowly from system of blood vessels and restore the blood volume quickly
At what dehydration % is fluid loss considered critical
At 10-12%
How to administer fluids in critically dehydrated patient
Must first be administered in vein, as subcutaneously, intraperitoneally and per os administered fluids are not absorbed by the highly dehydrated patient.
- Blood volume is reduced, and
concentrated in organs of vital
importance within the trunk
- Peripheral blood vessels are empty
and fluids administered in such regions
will not be absorbed.
Can also be administered intraosseously in case of puppies, kittens and small dogs.
- Tuberosity of tibia, medial proximal portion of tibia and hole between trochanters of femur
Fluid retention requirements
In the course of 24 hours
40-65ml/kg in adults
130ml/kg in young animals
- A 20kg dog will require 1.3 l / 24h
- A 450kg horse will require 29l/24h
How to calculate the fluid requirement
(30 x weight of animal) + 70 = … ml/day
How to administer the fluids (speed)
Rapidly at first and then at decreased rates until condition is corrected (bolus)
- Mild case: 15 ml/kg/hr reasonable
- Severe: up to 50 ml/kg/hr
Must be individually adjusted for each patient.
