types of fluid Flashcards
What are the four major groups of intravenous fluids?
Crystalloids, synthetic colloids, blood products, and haemoglobin-based oxygen carriers (HBOCs)
What do crystalloids contain that allows them to cross the capillary endothelium?
Electrolytes and other solutes
What is the main difference between crystalloids and colloids?
Colloids contain macromolecules restricted to the intravascular space
What are balanced crystalloids?
Crystalloids with electrolyte levels similar to plasma
What are unbalanced crystalloids?
Crystalloids with electrolyte content substantially different from plasma
Factors to consider when choosing a crystalloid fluid include:
Osmolality/tonicity, electrolyte content, presence of buffers
What is the osmolality of normal plasma?
Around 300 mOsm/kg
Define hypertonic solutions.
Fluids with osmolality greater than that of plasma
What is the only hypertonic solution available?
Hypertonic saline (HTS)
Typical concentration of HTS used in the UK is:
Around 7.2%
What effect does HTS have on fluid compartments?
Pulls water from intracellular to extracellular space
What is the typical bolus dose of HTS for dogs?
5 mL/kg
True or False: HTS expands intravascular volume by more than the amount administered.
True
HTS should be administered over not less than ______ minutes.
5
What is a potential adverse effect of HTS if given too quickly?
Reflex bradycardia, hypotension, and bronchoconstriction
What are isotonic crystalloid solutions used for?
To replace fluid losses from the extracellular space
Examples of isotonic crystalloid solutions include:
Hartmann’s solution and 0.9% saline
What is the osmolality range of isotonic crystalloids?
272-308 mOsm/L
What can excessive use of isotonic crystalloids lead to?
Electrolyte imbalances
What is the acidifying effect of 0.9% NaCl attributed to?
High chloride content
Hypotonic crystalloids are characterized by:
Low sodium and high potassium levels
What should NEVER be administered as a bolus due to risk of cerebral oedema?
Hypotonic solutions
What are free water solutions primarily used to treat?
Hypernatraemia
Synthetic colloids are solutions containing:
High molecular weight molecules that do not readily cross capillary endothelium
Three main groups of synthetic colloids include:
Hydroxyethyl starch (HES), dextrans, and gelatins
What is the main indication for HES?
As a resuscitation fluid for hypovolaemic patients
What is the maximum recommended dose of Voluven/Volulyte?
50 mL/kg/day
What adverse effects are associated with HES in critically ill patients?
Renal dysfunction and increased mortality
Dextrans are produced from ______.
Bacterial fermentation of sucrose
What are the serious adverse effects associated with dextrans?
Coagulopathies, renal failure, anaphylaxis, and hyperglycaemia
Gelatins are produced from ______.
Bovine collagen
What is a key concern regarding the use of synthetic colloids?
Adverse effects on renal function
What is Gelofusine?
A succinylated gelatin licensed for human use in the UK.
How does the half-life of Gelofusine compare to HES?
Considerably shorter than HES.
What is a key difference in side effects between Gelofusine and HES?
No dose-related side effects reported for Gelofusine.
What adverse effects are reported in people using Gelofusine?
Adverse effects on renal function.
What was observed in an experimental study in dogs regarding Gelofusine?
Greater increase in biomarkers of renal injury and renal tubular microvesiculation.
What components are found in the plasma of blood?
Albumin and other colloidal molecules.
What are fresh whole blood and fresh frozen plasma classified as?
Natural colloids.
What is the colloidal property of packed red blood cells?
Contain hardly any plasma and do not have colloidal properties.
What is the primary use of plasma products in transfusions?
To treat coagulopathies.
What are concentrated human serum albumin solutions (HSA) used for?
Resuscitation in people.
What prohibits the veterinary use of HSA solutions?
Serious safety concerns and expense.
What is Oxyglobin?
An acellular HBOC licensed for veterinary use.
What is the primary indication for Oxyglobin?
To provide oxygen carrying capacity in anaemic dogs.
What are the plasma expanding properties of Oxyglobin?
Excellent plasma expanding properties (COP 43 mmHg).
What risk does Oxyglobin pose in normovolaemic patients?
May cause fluid overload.
