IV fluids

Question 1

Fluid distribution among bod compartments

Answer 1

67% intracellular

33% extraellular

*Intravascular is only 6% of the whole body compartment

Question 2

Routine maintenance fluids- how much?

Answer 2

25-30 ml/kg/ day

*2-3 L for most people

Question 3

What’s Na+ requirement a day?

Answer 3

1-2 mmol/day

Question 4

What’s K+ requirement/day ?

Answer 4

1 mmol/day

Question 5

What’s Cl- requirement per day?

Answer 5

1-1.5 mmol/day

Question 6

What conditions require more fluids?

Answer 6

• vomiting
• diarrhoea
• diuresis
• bleeding
• burns
• hyperthermia
• sepsis

Question 7

Signs of volume depletion (dehydration)

Answer 7

• thirst
• dry mucous membranes
• skin turgor
• sunken eyes
• capillary refill time
• weight loss
• tachycardia
• hypotension (particularly postural)
• organ hypoperfusion

Question 8

What happens in postural hypotension?

Answer 8

When a person stands up BP falls too much

*normally BP should increase upon standing

Question 9

Signs of volume overload

Answer 9

• probable hypertension (possible hypotension)
• raised JVP
• weight gain
• tachycardia
• oedema (peripheral, pulmonary, ascites)
• end organ damage

Question 10

What is the best method to give fluids to the patient?

Answer 10

always aim for oral - the ideal way

Question 11

What are crystalloids composed of?

Answer 11

Solutions of water + electrolytes

Question 12

Can crystalloids move across semi-permeable membrane?

Answer 12

They can cross semi-permeable membrane -> can move between fluid compartments quickly/freely

Question 13

Examples (3) of crystalloid fluids

Answer 13

• dextrose
• saline
• Ringer’s Lactate (Hartmann’s)

Question 14

What are properties of normal saline?

Answer 14

Normal saline = 0.9%

Components: Cl-, Na+ and water

• cheapest and most commonly used
• used in fluid resuscitation
• replaces Na+ and Cl-
• only small proportion remains intravascularly (it moves the compartments)
• no calorie content

Question 15

Dextrose

• components
• use of 5%
• use of 70%
• use
• caution

Answer 15

Dextrose = sugar + water

• 5% and 10% used commonly
• 50% and 70% - used only in ITU (given through central line due to irritation to small peripheral veins)
• used for maintenance fluids (not for resuscitation) *unless in hypoglycaemic episode
• caution: Diabetes Mellitus

Question 16

Ringer’s Lactate (aka Hartmann’s)

• components
• what are the advantages

Answer 16

• Na + 130 mmol/l
• Cl - 109 mmol/l
• K+ 4 mmol/l
• Ca 1.5 mmol/l
• lactate

These are physiological and isotonic

Question 17

Colloids

• components
• do they cross semi-permeable membrane
• effect on plasma

Answer 17

Colloids

• Components: high molecular weight molecules
• These are less able to cross semi- permeable membrane
• They exert oncotic pressure -> fluid is pulled into the veins -> plasma expansion

Question 18

What are colloids useful in?

Answer 18

Colloids are useful in resuscitation when we try to raise BP

They exert oncotic pressure -> fluid is pulled into the veins -> plasma expansion

Question 19

Gelatins

• most commonly used
• composition
• risk
• use

Answer 19

Gelatins

Most common: Gelofusine

Composition: bovine collagen, sodium and chloride (densly packed molecules)

Risk: anaphylaxis, bleeding risk, prothrombotic

Use: peri-arrest situation, very unwell + hypotension -> to increase BP

Question 20

Examples of colloids

Answer 20

• gelatin
• hydroxyethyl starches

*these are plasma expanders

Question 21

Hydroxyethyl starches

• what they are

Answer 21

Hydroxyethyl starches -> colloids

• very large, semi-synthetic molecules - similar to glycogen
• they have large molecules = oncotic pressure -> can pull fluids intra vascularly

Use: fluid resuscitation, to replace intravascular volume

*usually used in critically ill patient/ ITU

Question 22

Adverse effects of use of Hydroxyethyl starches

Answer 22

• accumulation in interstitial spaces -> deposits in peripheral tissues (large molecules) -> pruritis / irritation of the skin
• coagulation problems
• anaphylaxis
• possible cause of renal impairment

Question 23

What’s the best fluid to administer if someone is bleeding?

Answer 23

blood

Question 24

When to use human albumin solution?

Answer 24

In a person with very low albumin

This may be due to: liver failure, nephrotic syndrome if we want to increase the albumin and therefore BP

*but we treat the cause usually

Question 25

When do we use Fresh Frozen plasma, cryoprecipitate?

Answer 25

***FFP, cryoprecipitate*** = clotting factors ## Footnote - bleeding - DIC - OD of direct oral anticoagulants

Question 26

What's the aim of fluid resuscitation?

Answer 26

To keep fluid intravenously (in intravascular space)

Question 27

What is usually given for fluid resuscitation in sepsis?

Answer 27

***Hartmann's*** or normal ***Saline*** (0.9%)

Question 28

In fluid resuscitation, can we use colloids on their own?

Answer 28

No, we use colloids in conjunction with crystalloids

Question 29

Do fluids require a prescription?

Answer 29

Yes! Just like any other drugs ## Footnote Include on prescription: - type of fluid - volume to be administrated - time and date to start - rate of fluid administration

Question 30

What IV fluid management plan should include details of?

Answer 30

\*that is according NICE guidelines, but rarely happens in reality * fluid and electrolyte prescription over the next 24 hours * assessment and monitoring plan * assessment of risks, benefits and harms of IV fluids

Question 31

Potential complications of fluid mismanagement

Answer 31

- hypovolaemia (before fluid administration) - pulmonary oedema - hyponatraemia - hypernatraemia - peripheral oedema - hyperkalaemia - hypokalaemia

Question 32

What daily assessments (monitoring) are required if the patient is continuing to receive IV fluids?

Answer 32

- clinical fluid status - laboratory values (haem, urea, creatinine, electrolytes) - fluid balance charts - twice weekly weight measurement \*long term IV fluid therapy - may require less monitoring but must be specified in ***IV*** ***fluid management plan***

Question 33

What monitoring is required in patients receiving IV fluids containing Cl \>120 mmol/l?

Answer 33

Daily chloride bloods

Question 34

NICE guidelines for Resuscitation

Answer 34

* ABCDE * identify cause of the deficit * give bolus of 500 ml of crystalloid * _reassess patient:_ further bolus of 250-500 mls crystalloid, expert help, continuous reassessment and ABCDE

Question 35

Can ***tetrastarch*** be used for fluid resuscitation?

Answer 35

NO !!!

Question 36

When to consider resuscitation with human albumin?

Answer 36

Only in patients with severe sepsis (resuscitation with human albumin 4-5%)