IV fluids - Dr Alice Ditchfield

Question 1

Give some broad indication categories for IV fluids

Answer 1

Maintenance
Replacement
Resus

Question 2

Maintenance indications - examples

Answer 2

NV
NMB
If not absorbing

Question 3

Replacement indications - examples

Answer 3

GI loss
Sweating 3rd burns
Surgery
D and V

Question 4

Resus indications - examples

Answer 4

Shock
Anaphylaxis

Question 5

How much of total body weight is intracellular fluid?

Answer 5

2/3

Question 6

How much of total body weight is extracellular fluid?

Answer 6

1/3

Question 7

Extracellular fluid can be split into

Answer 7

Interstitial fluid (between cells)
Plasma
Transcellular fluid (within epithelial linings/glands, aka secretions

Question 8

What portion of extracellular fluid is interstitial?

Answer 8

3/4 is interstitial

Question 9

What portion of extracellular fluid is in plasma?

Answer 9

Only 1/4

Question 10

What is osmolality and what is the normal range?

Answer 10

It is the concentration of a solution, expressed as solutes per kg

Normal - 275-295 mili osmoles per kg

Question 11

What are the three types of fluid we can give?

Answer 11

Crystalloids
Colloids
Blood

Question 12

Name three types of crystalloids

Answer 12

Hypotonic solution (would make fluid leak out of blood)
Isotonic solution (Hartmanns)
Hypertonic solution (would draw fluid into blood)

Question 13

Give two examples of isotonic solutions

Answer 13

Hartmanns - 270+ osmoles
NaCl 0.9 percent - 300+ osmoles

Question 14

What is another name for Hartmann’s

Answer 14

Compound sodium lactate

Question 15

When can you not given Hartmann’s and why

Answer 15

Liver failure - inability to metabolise lactate
Renal failure - risk of hyperkalemia

Question 16

Give an example of a colloid

Answer 16

Human albumin solution

Question 17

Resus regimen

Answer 17

500ml 0.9 percent NaCl, or 250ml if elderly/with co-morbidities

Question 18

Maintenance regimen

Answer 18

1 salty, 2 sweet
e.g. (not complete picture, see next flashcard)

500ml 0.9percent NaCl over 8 hours
1L 5 percent dextrose over 8 hours
500ml 5 percent dextrose over 8 hours

Question 19

What do you need to remember to add to the maintenance regimen?

Answer 19

POTASSIUM

aka

500ml 0.9percent NaCl + 20mmol POTASSIUM
1L 5 percent dextrose + 20mmol POTASSIUM
500ml 5 percent dextrose + 20mmol POTASSIUM

Question 20

If someone has hypokalemia, how much potassium can you add to the NaCl bag

Answer 20

40mmol

Question 21

What is the maximum rate of potassium delivery via IV

Answer 21

10mmol/hr

Question 22

ECG changes in hypokalemia

Answer 22

T wave flattening
U wave
Prolonged QT interval

Question 23

ECG changes in hyperkalemia

Answer 23

Tall tented T waves
Broadened QRS
Wide PR interval

Question 24

Management of hyperkalemia

Answer 24

Repeat VBG
Double check that the bloods are haemolysed

10ml 10 percent calcium gluconate
50ml 50 percent dextrose over TEN MINUTES
10 units of Actrapid
Salbutamol nebs 5mg (max 4 times)
Check U and Es 4 hrs later
Repeat ECGs
Consider haemodialysis for refractory hyperkalemia

Question 25

Normal range for calcium

Answer 25

2.2-2.6mmol

Question 26

Symptoms of hypocalcemia

Answer 26

Muscle cramps Convulsions Arrhythmias Tetany - Trussau's carpopedal spasm in response to BP cuff, or Chvostek's sign - tapping the cheek in front of the ear causes facial spasm Parasthesias

Question 27

What's the management of hypocalcaemia?

Answer 27

>1.9 - Adcal <1.9 - monitor heart, give IV calcium gluconate Remember to replace any low magnesium?

Question 28

Management of hypercalcemia

Answer 28

IV fluids Bisphosphonate

Question 29

Normal range for phosphate

Answer 29

0.5-1.5

Question 30

Management of hypophosphatemia

Answer 30

Phosphate sandoz tables

Question 31

Normal range of magnesium

Answer 31

0.7-1

Question 32

Management of low magnesium

Answer 32

>0.41 - oral tablets <0.4 - IV mag sulf 20mmol in 250ml NaCl over 6 hours

Question 33

In a head injury what do you give

Answer 33

NORMAL SALINE because you don't want to shift the fluids in the brain too quickly