Fluid prescribing adults Flashcards
What are the two major types of fluids
Crystalloids - eg NaCl, Hartmanns, dextrose
Colloids - larger molecules eg albumin, gelofusine
Why are crystalloids used more than colloids
Colloids are used less often than crystalloid solutions as they carry a risk of anaphylaxis and research has shown that crystalloids are superior in initial fluid resuscitation
What are the 5 Rs of fluid prescribing
Resuscitation
Routine maintenance
Replacement
Redistribution
Reassessment
History fluids
Fluid intake:
Assess if the patient’s fluid intake been adequate.
Symptoms suggestive of dehydration:
Thirst
Dizziness/syncope
Fluid loss:
Vomiting (or NG tube loss)
Diarrhoea (including stoma output)
Polyuria
Fever
Hyperventilation
Increased drain output (e.g. biliary drain, pancreatic drain)
Co-morbidities:
Heart failure
Renal failure
fluid resus in adults
500ml sodium chloride 0.9% over less than 15 minutes
when should you be cautious fluid resus
If patients have complex medical comorbidities (e.g. heart failure, renal failure) and/or are elderly then you should apply a more cautious approach to fluid resuscitation (e.g. giving fluid boluses of 250 ml rather than 500 ml and seeking expert help earlier).
what questions to ask yourself when prescribing maintenance fluids for adults
what have they had?
what do they need ? (water, electrolytes, glucose)
are there any contraindications eg to glucose fluids?
what timeframe should i do this over?
maintenance fluid daily requirements
25-30 ml/kg/day of water and
approximately 1 mmol/kg/day of potassium, sodium and chloride and
approximately 50-100 g/day of glucose to limit starvation ketosis (however note this will not address the patient’s nutritional needs)
indication for routine maintenance
haemodynamically stable but unable to meet their daily fluid requirements via oral or enteral routes
what water requirement adults will you use in most circumstances
25ml/kg/day!!
as normal = 25-30
elderly/co-morbid etc 20-25
so for psa always do 25
in what circumstances should you be cautious about glucose fluids
AVOID in first 24 hours after ischaemic stroke or head trauma - risk of cerebral oedema
caution in impaired glucose tolerance,
caution in severe malnutrition (risk of re-feeding),
caution in thiamine deficiency
max rate of potassium infusion
10mmol/hr
potassium prescribing - what are your options
comes in set bags (never added into fluids)
As part of 5% glucose or NaCl
0.15% = 20mmol in 1L
0.3% = 40mmol in 1L
tend to go for 0.3% to get up to requirements /day
Prescribe a drug for hypoglycaemia
glucagon
prescribe an IV fluid for hypoglycaemia adults
Glucose 10% - 150mls over 15 minutes
15-20g over 15 mins as 10% glucose or 20% glucose
