Fluids

Question 1

What is required in maintenance fluids?

Answer 1

25ml/kg/24hrs water
1mmol/kg/24hrs Na+,K+,Cl-
50-100g/24hrs glucose

Question 2

Crystalloids

Answer 2

Plasmalyte
Hartmann’s
0.9% NaCl
5% dextrose
0.18% NaCl in 4% dextrose

Question 3

Colloids

Answer 3

Albumin

Question 4

Isotonic fluids

Answer 4

0.9% NaCl
Hartmann’s
Plasmalyte

Question 5

Hypotonic fluids

Answer 5

5% dextrose
0.18% saline

Question 6

Hypertonic fluids

Answer 6

3% saline

Question 7

Normal blood electrolytes

Answer 7

Sodium 142 mmol/litre
Potassium 4.5 mmol/litre
Bicarbonate 26 mmol/litre
Chloride 103 mmol/litre
Calcium 2.5 mmol/litre

Question 8

0.9% NaCl electrolytes

Answer 8

Sodium 150 mmol/litre
Chloride 150 mmol/litre

Question 9

Hartmann’s (compound sodium lactate) electrolytes

Answer 9

Sodium 131 mmol/litre
Potassium 5 mmol/litre
Bicarbonate 29 mmol/litre
Chloride 111 mmol/litre
Calcium 2 mmol/litre

Question 10

Plasmalyte electrolytes

Answer 10

Sodium 140 mmol
Chloride 98 mmol
Potassium 5 mmol
Magnesium 1.5 mmol

Question 11

0.18% NaCl in 4% dextrose

Answer 11

Sodium 30 mmol/litre
Chloride 30 mmol/litre
Glucose 40g

Question 12

5% dextrose

Answer 12

No electrolytes
Glucose 50g

Question 13

Normal urine output

Answer 13

0.5ml/kg/hr

Question 14

It is possible to roughly predict how fluid-depleted an adult
patient is by using their observations and knowing which are
affected first:

Answer 14

Reduced urine output (oliguric if <30mL/h; anuric if 0 mL/h) indicates 500mL of fluid depletion

Reduced urine output plus tachycardia indicates 1 L of fluid depletion

Reduced urine output plus tachycardia plus shocked indicates >2 L of fluid depletion.

Question 15

How much fluids to adults roughly require in 24hrs

Answer 15

As a general rule, adults require 3L IV fluid per 24 hours and the elderly require 2L

Question 16

IV potassium should not be given at more than ___mmol/hour

Answer 16

IV potassium should not be given at more than 10 mmol/hour

Question 17

How fast should you give fluids?

Answer 17

If giving 3 L per day = 8-hourly bags (24 ÷ 3)
If giving 2 L per day = 12 hourly bags (24 ÷ 2)

Question 18

Everytime you prescribe fluids in real life you should…

Answer 18

Check the patient’s U&E to confirm what to give them

Check that the patient is not fluid overloaded (e.g. increased
jugular venous pressure (JVP), peripheral and pulmonary oedema).

Ensure that the patient’s bladder is not palpable (signifying urinary obstruction) if giving replacement fluids because of
‘reduced urine output’.