Fluid prescribing

Question 1

stages of fluid prescribing

Answer 1

Assessment

Fluid Resuscitation

Fluid Maintenance

Replacement and redistribution

Question 2

when is fluid resus indicated

Answer 2

Indication: BP <90mmHg

• e.g. low blood pressure due to sepsis

Question 3

prescription for fluid resus

Answer 3

500ml normal saline over 15 mins

• check BP and if still low repeat

Question 4

fluid resus for patient with HF or kidney failure

Answer 4

250ml or 500ml over 30 mins

Question 5

calculating fluid balance

Answer 5

Total input- total output = fluid balance

(anything going in) – (anything going out)

Question 6

example fluid balance

Answer 6

Total in= (83x6)+ (20x2)= 538ml

Total out= 815 (look at running total out)

• Could add 800ml for insensible losses

Therefore 538- 815= -277

Therefore, the fluid balance is negative

• Patient requires IV fluids

Question 7

example fluid balance

Answer 7

Total in= 2608 (looking at running total in)

Total out= 1690(look at running total out)

Therefore- 2608-1690= 918

Therefore, the fluid balance is positive- patient is fluid overloaded

Question 8

maintenance water for adults

Answer 8

• Water: 25-30ml/kg/day
  
  • Go with 30 (upper limits)
    *

Question 9

maintenance Na/K/Cl for adults

Answer 9

1mm/kg/day

Question 10

maintenance glcuose for adults

Answer 10

50g/day

Question 11

LEARN THIS to figure out which IV fluids patient needs

Answer 11

• Remember can be a mixture
• Bags can be halved
• Doesn’t need to be exact
• Potassium can be added
• If patients bloods show high Na, think about giving dextrose saline since it has much less Na in it than sodium chloride
• Rule of thumb: in surgery say Hartmanns, in medicine say saline.

Question 12

calculate maintenance for: 70kg man nil by mouth after esophagectomy needs is fluids maintained.

Answer 12

• Therefore, if he is 70kg
  
  • Water: 30x 70kg= 2,100 (around 2l)
  • Na/K/Cl: 70mmol/day each
  • Glucose: 50 g/day
  • Therefore, if patient is 70kg needs 2l over 24hours

Question 13

which IV fluids: 70kg man nil by mouth after esophagectomy needs is fluids maintained.

Answer 13

• Now to decide which IV fluids to use
  
  • He needs around 70mmol of Na and K and Cl-
    
    • Na+ and Cl-
      
      • 1 bag of saline offers 154mmol/l of Na and Cl—we only need around half of this, therefore we will only give half a bag (500ml)
        
        • Therefore 77mmol/l of both Na and Cl-
      • After this we have got enough salts
    • K+ we need to add it
      
      • Comes in either 20mmol/l or 40mm/l
      • So give x1 20mg with first bag and x1 40mg with second bag
    • Glucose
      
      • May need to give extra glucose to give the right amount of IV fluids
        
        • Can give 1x 500ml dextrose= 25g/l
        • Can give 1x 1l dextrose= 50g/l
        • 75g overall is more than 50g but okay
• Final Fluid regime
  
  • 1^st bag: 500ml saline +20 K+ over 6 hours
  • 2^nd bag: 500ml dextrose 40K+ over 6 hours
  • 3^rd bag: 1l dextrose over 12 hours
    
    • Total of Na 75, Cl75, glucose 75 (which is>50g, but ok)

this is a classic 1 salty 2 sweet

Question 14

maintenance and deficits

Answer 14

If patients fluid balance is negative, the patient will need maintenance + deficits

Question 15

maintenance and deficits

Answer 15

If patients fluid balance is negative, the patient will need maintenance + deficits

Question 16

example working out maintenance and deficit: first calculate fluid balance

Answer 16

Question 17

example working out maintenance and deficit: next calculate fluid requirements for 60kg women

Answer 17

• Therefore, if Svetlana is 60kg
  
  • Water: 30x 60kg= 1,800ml (around 2l)
  • Na/K/Cl: 60mmol/day each
  • Glucose: 50 g/day

Question 18

example fluid regime for maintenance and deficits

• Water: 30x 60kg= 1,800ml (around 2l)
• Na/K/Cl: 60mmol/day each
• Glucose: 50 g/day

Answer 18

• Need around 1800ml of water for maintenance and + 227 for deficit which is around 2l (2077ml)
  
  • Therefore, will need two 1l bags of IV fluid
  • Rate of administration should be constant i.e. 2l would be given as 2, 1l bags over 12 hours each = 24 hours in total
  • Now to decide which IV fluids
    
    • She needs around 60mmol of Na and K and Cl-
      
      • Na- and Cl- sorted if we use x2 dextrose bags i.e. 31mmol/l in 1 bag, so 62mmol/l if 2 bags given
      • K+ we need to add it
        
        • Comes in either 20mmol/l or 40mm/l
        • So give 20mm/l with 1 dextrose bag and the 40mmol/l with the other dextrose bag
    • Each bag of Dextrose saline also offers 40g of glucose – 80g is okay- close enough to 50g needed

Question 19

example 2: what first

Answer 19

calculated fluid balance

Question 20

example 2: calc fluid balance

Answer 20

• Total fluid input is calculated by adding together the individual inputs shown on the fluid balance chart (oral, IV fluids, drug boluses/infusions).
• Similarly, the total output is calculated by adding together the individual outputs shown on the fluid balance chart. It is crucial to remember, however, that insensible losses are not shown on the fluid balance chart, but must be taken into consideration.
  
  • In this case, you have been asked to assume that insensible losses are 800 mL per day.

therefore:

3000- (1760+100+100+300 + 800)= -60mls

*800 for insensible losses

Question 21

example 2: after calculating fluid balance, calc requirement for the next 24 hours

Answer 21

Daily requirements

Pt is 98kg

• Water: 98 x30= 2.94 L (maintenance)
  
  • • deficit (0.06)
      
      • The minor excess losses over the preceding 24 hours (0.06l) can be added on to give a total fluid requirement of 3.0L over the next 24 hours
• Electrolyte requirement
  
  • Na/K/Cl- 98mmol
    
    • Potassium should not be prescribed at a rate greater than 10mmol/hour
  • Glucose 50g

Question 22

example 2: which fluids

Answer 22

Start with 8h (hydrate quickly), then 10, then 12