What are the Rs of fluids?
Reasons to give fluids
Resuscitation Routine maintainance Replacement Redistribution Reassessment
What are the fluid compartments
2/3 = intracellular fluid
1/3 = extracellular fluid
- 1/5 = plasma
- 4/5 = interstitium
What is the normal daily requirement of water?
25 ml/kg/day
What is the normal daily requirement of glucose?
50g/day
What is the normal daily requirement of electrolytes?
1mmol/kg/day
Signs of hypovolaemia (fluid deplete)
Dry mucous membranes Reduced skin turgor Decreased urine output Orthostatic hypotension Confusion
Signs of hypervolaemia (fluid overload)
Shortness of breath
Raised JVP
Pitting oedema
What are crystalloids?
Electrolytes
Small molecules - diffuse across membranes
What are colloids?
Larger molecules - do not readily cross capillary walls
High colloid osmotic pressure
What do you give for resuscitation fluids?
500ml STAT
Hartmanns or NaCl 0.9%
What do you give for maintenance fluids?
Can give Hartmanns
Or
- 500ml saline with 20mmol/L K over 8 hours
- 1L 5% dextrose with 20mmol/L K over 8 hours
- 1L 5% dextrose with 20mmol/L K over 8 hours
Tell me about 0.9% saline
Moves 75% into interstitial fluid and 25% plasma
Risks
- hyperchloraemic acidosis
- fluid overload
Tell me about 5% dextrose
Hypotonic
Equal distribution - glucose metabolised so water spreads
Not great for increasing plasma volume
Tell me about Hartmanns
Contains
- sodium
- chloride
- potassium
- bicarbonate
- calcium
- lactate
Most similar to plasma
Cannot be used alone for maintainence
