Flashcards in Fluid Therapy Deck (22):
When is fluid therapy needed at a fundamental level?
When there is a loss of fluids and when there is a need to maintain fluid levels.
What is the 'third space'?
It is when fluid is sequestered in the wrong places e.g. peritoneal cavity/lungs.
The 'first' and 'second' spaces are the ECF and ICF compartments.
How is total body fluid distributed in the body?
1/3 ECF 2/3 ICF
-tissue fluid (3/4)
Why is blood loss so severe in its consequences?
Only a very small portion of total body fluid is circulating in the plasma therefore the room for loss is very small.
How can a fluid defect be identified? Which is the best way?
The best way is from the history and physical exam. Blood results are useful for showing a metabolic disturbance but don't give a clear picture of the hydration status of an animal.
Why is the rate of fluid therapy important?
If given fast then the fluid will distribute less evenly => a bolus is good for shock.
If given slow it will distribute more evenly => drip is good for dehydration.
Why does skin turgor indicate hydration status? If an animal has 'gelatinous' skin, what will this indicate?
The fat under the skin absorbs water. Gelatinous would indicate water retention. (specifically ECF retention)
Does dehydration commonly progress to shock?
Not in adult/larger animals. It is more likely in puppies and other young animals
Other than hypovolaemia or dehydration, what is fluid therapy indicated for? Give reasons why.
Animals under GA - many homeostatic systems are suppressed
Flushing things out - increases GFR, water soluble toxins may also benefit from fluid therapy
What can make up a fluid bag?
Why is fluid therapy used?
Correct electrolyte imbalance
Correct acid-base problems
Delivery of drugs (dilution/constant infusion)
How are fluids classified?
Crystalloid or colloid
What is a disadvantage of crystalloid fluids?
They have a very even distribution once administered. Only a 1/3 will remain intravascularly so may need quite a bit when treating for hypovolaemia.
How do colloids differ from crystalloids?
They generate vascular oncotic pressure as they have synthetic protein/starch based components so are useful for intravascular resuscitation.
What are the side effects of colloids?
Fluid overload and coagulopathy. n.b. there is no indication that they have more benefit than crystalloids.
What natural colloids are available?
Human albumin - have side effects in animal use
(Canine albumin) - these are not really available commercially.
(feline albumin) - these are not really available commercially.
Are parenteral nutrition bags crystalloid or colloid and what goes into them?
Crystalloid. Amino acids, lipids and dextrose go into them
What are the indications for use of a hypertonic solution and a hypotonic solution.
Hyper - can inject to 'borrow' fluid from other compartments for intravascular resuscitation
Hypo - only in animals with very high sodium. USE WITH CARE
Give examples of hypertonic solution.
Why is mannitol useful?
It is a sugar alcohol so is not absorbed by the body and is only excreted by the kidney so will help animals with oedema as water will follow it out. (Osmotic diuretic)
When should colloid use be considered?
Need rapid resuscitation or the effect needs to last longer than 1hr. Need to increase COP or in oedematous animals.