Intravenous fluid Flashcards
What is diffusion?
Movement of solute from high concentration to low concentration
The membrane must be solute permeable
What is osmosis?
Movement of water from high concentration to low concentration
The membrane must be solute impermeable
What is osmolarity?
The measure of solute concentration per unit volume of solvent
What is osmolality?
The measure of solute concentration per unit mass of solvent
What is tonicity?
The measure of the osmotic pressure gradient between two solutions
How is the fluid in the body split up into the different compartments?
2/3 of the fluid within the body is in the intracellular space. The remaining third is split into 20% in the plasma and 80% in the interstitial space.
How much water is required by an adult daily?
25-30 ml/kg
How much sodium is required by an adult daily?
1mmol/kg
How much potassium is required by an adult daily?
1mmol/kg
How much glucose is required by an adult daily?
50-100g
What basic questions should you ask yourself during fluid assessment?
- What is my patients volume status?
- Does my patient need IV Fluids?
- How much fluid do they need?
- What types of fluid do they need?
How is a patient’s volume status established?
ABCDE approach to find cause of fluid challenge and treat it
What are the characteristics of a euvolaemic patient?
Feels well, not Thirsty Veins well filled Warm extremities Mild sweat Normal BP and HR Normal Urine
What are the requirements of a euvolaemic patient?
No fluids
What are the characteristics of a hypovolaemic patient?
Feels nauseous, thirsty Flat veins Cool peripheries No sweat Low or postural BP and high HR Concentrate oliguria Responds to SLR
What are the requirements of a hypovolaemic patient?
Resuscitation fluids (if low BP) Rehydration fluids
What are the characteristics of a hypervolaemic patient?
Feels breathless, not thirsty Veins distended Warm and oedematous extremities Sweaty High BP and High HR Dilute urine (could be oliguric or polyuric)
What are the requirements of a hypervolaemic patient?
No more fluids
Possibly diuretics (if respiratory compromise)
Haemofiltration (if anuric)
How does presentation of patients with a low oncotic pressure or heart failure contradict their fluid status?
Low albumin or protein can cause oedema in dehydrated patients due to a lack of intracapillary fluid. These patients tend to be oedematous, with a low blood pressure, high heart rate and thirst.
How should fluids be given to patients?
If oral route is viable, use it before giving intravenous fluid
How is the volume of fluid required decided?
Water deficit is calculated based on the following:
Catheters, drains
Input charts
Vomit bowls
Sputum Pots
Stool charts and stoma losses
Insensible losses (sweating, ventilation, open wounds, burns and bleeding)
What are the five R’s of fluid management?
Resuscitation Routine management Replacement Redistribution Reassessment
What is dextrose useful in?
Chronic dehydration
Hypernatraemia
What are crystalloids useful in?
Acute dehydration
AKI
Resuscitation
What are plasma expanders useful in?
Liver patients
Select intra-operative
