Fluid tx

Question 1

How is water divided up within the body?

Answer 1

1/3 intra vascular
- within this 1/4 intravascular, 3/4 interstitial
2/3 intracellular
- need change in Na to affect water movement here

Question 2

What is Starlings law?

Answer 2

Balance of oncotic and hydrostatic pressure within and outside capillaries

Question 3

Potential complications from too much fluid?

Answer 3

• pulmonary oedema
• interstitial oedema (subcut oedema, organs, v function)
• 3rd spacing
  > clinics, signs
• pulm crackles
• peripheral oedema
• chemosis of the eyes
• bilateral serous nasal discharge
• jugular distension, pulsation
• increase body weight (weigh 3x a day)
• large left atrium on us

Question 4

Which patients are at risk of fluid overload?

Answer 4

• cardiac or pulmonary disease
• oliguric/anuric renal failure
• geriatric cats
• hypoalbumenaemia
• Sepsis/SIRS

Question 5

How does Tx of shock and dehydration differ?

Answer 5

Shock intravascular 
Dehydration interstitial (NOT INTRACELLUALR)

Question 6

Goals for Tx of shock?

Answer 6

• fluid bolts to fill intravascular space
• Tx until 6 perfusion parameters Normal
• care to not give too much (at risk patients)
• defo no more than one blood volume (80ml/kg dog, 50ml/kg cat)
• Tx underlying causes

Question 7

5 questions to think about wrt IVFT?

Answer 7

1. Type
2. Dose/rate (dose shock, rate dehydration)
3. Additive
4. Delivery
5. When to stop

Question 8

Outline board fluid types LOOK UP

Answer 8

> crystalloid
- isotonic (Hartmanns, CSL, LRS, 0.9% nacl)
- hypertonic (7.5% NACl)
- hypotonic (0.45% NaCl, 5% Dextrose)
> colloid (high oncotic pressure) 
- synthetic (Volulyte)
- Natural (blood products, albumin)

Question 9

Which fluids do you not use for shock treatment?

Answer 9

HypOOO tonic

Question 10

Which fluids are balanced and which are not?

Answer 10

• Hartmanns
• LRS
• CSL
  > Na, K, Cl, Ca, Lactate

Question 11

Which fluids are not balanced?

Answer 11

• 0.9% NaCl

- Na and Cl only

Question 12

What are the 3 main substances in balanced crystalloid a (Hartmanns etc) ? Why are they there?

Answer 12

> lactate
- metabolised to bicarbonate
- tx metabolic acidosis (which occour in shock)
potassium
- Some worry about ^ K but doesn’t usually cause hyperkalaemia as diuresis causes ^ renal excretion
calcium
- BEWARE chelates with sodium citrate preservative in blood products so don’t give together

Question 13

Indications for isotonic crystalloids

Answer 13

• all causes hypovolaemic shock
• obstructive shock (GDV)
• vasodilatory shock
• dehydration maintInance
• diuresis (azotaemia, toxicity)
• Tx metabolic acidosis (Hartmanns, CSL, LRS)
• Tx metabolic alkalosis (0.9% Nacl)

Question 14

Dose isotonic crystalloids?

Answer 14

• dogs 10-20ml/kg IV
• cats 5-10ml/kg IV
  > over 15 minutes
  > repeat up to 4 times (monitor, if no improvement after 2 doses, STOP)

Question 15

Indications for hypertonic saline

Answer 15

• traumatic brain injury (can occour with hypoxia in cardiac arrest)
• cerebral oedema
• large breed dog (^ intravascular space quicker)
• CPR
• used commonly in equine

Question 16

Contraindications for hypertonic saline?

Answer 16

• hyper/hyponatraemia

- dehydration

Question 17

Doses of hypertonic saline

Answer 17

2-4ml/kg over 10 minutes

• once ONLY
• follow with isotonic crystalloids

Question 18

How do colloids work?

Answer 18

Prevent fluid leaving intravascular space (DO NOT DRAW WATER IN FROM INTERSTITIAL SPACE !!)

Question 19

Indications for artificial colloids

Answer 19

• severe hypoproteinaemia

- large dog

Question 20

Potential adverse effects/contraindications for artificial colloids?

Answer 20

• kidney injury or renal failure
• coagulopathy
• ^ risk fluid overload
• sepsis (^risk kidney injury)

Question 21

Dose of artificial colloids

Answer 21

• dogs 5-10ml/kg over 15 mins
• cats 2.5-5 ml/kg over 15 mins
• repeat up to 4 times

Question 22

How does delivery of fluids differ between species ?

Answer 22

• small dog (fluid pump)
• medium large dog (pressure bag)
• cats (careful!!! 50ml syringe, by hand, or syringe driver, or pump with paediatric burette)

Question 23

What is the maintainance fluid rate?

Answer 23

• normal daily fluid requirement
• isotonic crystalloids
  > 2ml/kg/hr

Question 24

What are the 3 components of fluid therapy (ongoing)?

Answer 24

Maintainance + replacement (dehydration) + ongoing losses

Question 25

What levels of dehydration are noticeable on clinical exam? LOOK UP

Question 26

How can replacement fluid amounts be calculated?

Answer 26

Total amount in mls = (% dehydration / 100) X body weight (kg) X 1000
~ administer over 8-24 hours

Question 27

Causes of ongoing losses?

Answer 27

• VD+
• 3rd spacing
• wounds
• PU

Question 28

How can ongoing losses be measured?

Answer 28

• measure/weigh (VD+ urine)

Estimate (0.5-1.5x maintainance)

Question 29

Indications for using hypotonic saline?

Answer 29

Tx hypernatraemia

NOT DEHYDRATION OR SHOCK

Question 30

When may potassium chloride be added to fluids?

Answer 30

• hypokalaemia (VD+, PU)

- don’t exceed >0.5mmol/l/kg/hr

Question 31

When would potassium phosphate be spiked?

Answer 31

Hypophosphataemia (diabetic ketocidosis)

Question 32

When is dextrose added to fluids?

Answer 32

Hypoglycaemia

Question 33

What should be remembered when using potassium spiked fluids?

Answer 33

Don’t bolus!! If animal goes into shock get new bag of CSL

Question 34

Indications for IVFT

Answer 34

• shock
• dehydration (Tx and prevention)
• acidaemia/alkalaemia
• electrolyte imbalance (K, P, Na)
• hypoglycaemia
• azotaemia
• toxicity
• anaesthesia
• parenteral nutrition