Fluid Therapy Flashcards
What are the bodies fluid compartments?
Discuss whole blood loss?
Possible causes: severed superficial arteries or large veins.
Compartment lost from: intravascular
compartment.
Components of fluid lost: water,
colloidal particles, red cells and electrolytes, platelets, clotting
factors etc.
Discuss extracellular fluid losses?
Possible causes: Diarrhoea, diuresis,
sweating, “3rd space losses”
Compartment lost from: Interstitial
compartment and intravascular
compartment
Components in fluid lost: Na+, Cl- and water
Discuss protein rich extracellular fluid losses?
Possible causes: Some pleural/peritoneal
effusions, G.I. sequestration, protein losing enteropathies, burns.
Compartment fluid lost from: interstitial
compartment and intravascular
compartment
Components in fluid loss: Na+, Cl-, water and
proteins!
Discuss Pure water fluid losses?
Possible causes for loss e.g. high respiratory
rate or primary water deprivation
Compartments losses from: as pure water
loss as water moves freely across all
compartments, water is lost from all
compartments
Improve
What is the maintenance rate for cats and dogs?
*50ml/kg/day or 2ml/kg/hr (3-3.5 in cats)
Should provide water and electrolytes
*Na+
*Cl-
*K+
Discuss colloid fluids and what they’re for?
*Colloids are fluids in which large molecular
weight particles are suspended but not visible.
*Colloids contain large molecules that cannot
pass through the vascular endothelium
*They increase the colloid osmotic pressure of
the plasma, they also ‘pull’ water from the
interstitial space into the intra vascular space
*Make sure you pay back the fluid
What are natural colloids?
Natural colloids
*Plasma
*Albumin preparations
*Whole blood
What are some artificial colloids?
*Starches
*Gelofusin
*Dextrans
What should be considered when calculation IVFT?
If replacing loss….
– Think what type of fluid has been lost
– Think how much fluid has been lost
– Think how quickly that fluid has been lost
Improve International
What are maintenance fluids?
Amount of fluid an animal needs to match its normal losses
What are the objective and subjective ways to measure dehydration?
Subjective tests:
skin turgor, mucous
membranes, sunkeness of eyes.
Objective tests; urea, pcv, total protein, USG,
sodium.
Put the clinical information together to get a picture of % dehydration.
How can you correlate clinical signs to percentage dehydration?
How do you calculate a fluid deficit?
*The % figure means the % of body weight
*So 10% dehydrated 20kg dog
=10/100 x 20 = 2kg =2,000g = 2,000ml
*This deficit should be addressed in the first 12-24 hours
*In more acute cases, can be addressed in 1-4
hours
*Remember to add on top the animals
‘maintenance’ rate
Look at this example of calculating a fluid deficit?
*3kg cat off food and limited oral intake for 2
weeks
*Quiet but ambulatory
*Approx 10% dehydrated
*10/100 x 3 = 300g = 300ml fluid
*Maintenance 3.5ml/kg/hr over 24 hours = 252ml
*= 552ml over first 24 hours
*= 23 ml/hr
How can you use fluids to manage hypotension under
anaesthesia?
How much total blood volume do cats and dogs have?
*Dog = 90ml/kg total blood volume
*Cat = 56ml/kg total blood volume
A fluid is termed hypertonic, isotonic, or hypotonic based on?
Higher, equal, or lower
concentrations of electrolytes (usually sodium) compared to normal plasma.
Hypotonic: Na+ concentration is lower than plasma
Isotonic: Na+ concentration is similar to plasma
Hypertonic: Na+ concentration is higher than plasma
An animal’s maintenance requirement is defined as?
The amount of water and electrolytes
required to replace those lost through normal physiological processes, i.e. through respiration,
perspiration and excretion via the alimentary and urinary tracts.
Discuss replacing blood loss with fluids?
Only one third of crystalloid fluid remains in the intravascular space after a time, the rest
will pass into the other fluid compartments. So remember that if you are using crystalloids
to replace small volumes of blood loss that you will therefore need to administer three
times to blood loss to be able to replace the intra-vascular volume. If you are using blood
or colloids however, they will remain in the intravascular space and so you only need to
give the equivalent fluid volume to the blood lost.
