IVFT

Question 1

Perfusion parameters of vasoconstrictive shock

Answer 1

1. Obtunded
2. MM colour: pale-white
3. CRT >2
4. HR: tachy in dogs, either in cats
5. Weak-thready pulses
6. Cold extremities

Question 2

Perfusion parameters of vasodilatory shock

Answer 2

1. Obtunded
2. hyperaemic mm
3. <1s CRT
4. HR: tachy in dogs, either in cats
5. Bounding pulses
6. Warm extremities

Question 3

How is total body water divided between the body compartments?

Answer 3

1/3 ECF and 2/3 ICF

w/in ECF 1/4 IV and 3/4 Interstitial

Question 4

how are osmolality and osmolarity different?

Answer 4

Osmolality = mOsm/kg of solution
Osmolarity = mOsm/L of solution

Question 5

Define hyperosmolar

Answer 5

osmolality greater than plasma

Question 6

Define hyposmolar

Answer 6

osmolality less than plasma

Question 7

what is an ineffective osmole?

Answer 7

crosses the cell membrane freely and thus does not draw water out of the ICF

Question 8

How do hypotonic fluids effect water moves?

Answer 8

water moves out of the ECF and into the ICF

Question 9

how do hypertonic fluids effect water moves?

Answer 9

water moves out of the ICF and into the ECF

Question 10

what are the 3 arms of starling’s forces?

Answer 10

1. Hydrostatic pressure
2. Oncotic pressure
3. Endothelial permeability

Question 11

define hydrostatic pressure

Answer 11

pressure generated w/in the capillary by the fluid w/in and directly proportional to volume

Question 12

define oncotic pressure

Answer 12

a pressure gradient generated by the presence of numerous colloid molecules that do not readily cross the capillary endothelium

Question 13

abnormal fluid losses are usually…

Answer 13

isosmolar (w/ the same salt conc. as the plasma) thus it is only lost from the ECF compartment

Question 14

water will only move from the ICF when ??? changes

Answer 14

osmolality

Question 15

free water loss can occur if..

Answer 15

kidneys are not functioning (and anti-diuretic hormone not doing its job) + decreased water intake

Question 16

3 types of shock

Answer 16

• circulatory
• hypoxic
• metabolic

Question 17

types of circulatory shock

Answer 17

• hypovolaemic (+haemorrhagic)
• obstructive
• cardiogenic
• distributive/vasodilatory

Question 18

causes of hypovolaemic shock

Answer 18

loss of salty water/plasma from the IV space eg. severe dehydration, rapid loss of plasma into the GIT, body cavity, interstitial space

Question 19

causes of obstructive shock

Answer 19

when flow of blood bak into the right atrium, or from the right atrium to the left is prevented by physical obstruction
eg. pericardial effusion leading to right atrial tamponade, gastric dilation and volvulus (gas distended stomach compresses the CdVC and potentially the portal vein), severe PTE, severe heartworm infestation obstructing flow out of the right heart

Question 20

causes of cardiogenic shock

Answer 20

disease of the myocardium itself

eg. DCM, endotoxin and cytokine release during sepsis, severe brady/tachyarrythmias

Question 21

cause of vasodilatory/distributive shock

Answer 21

cytokines and other vasoactive mediators released w/ systemic inflam/anaphylaxis can cause endothelial dysfunction and dilation of the systemic arteries and arterioles, decreasing SVR

Question 22

perfusion parameters of moderate vasoconstrictive shock

Answer 22

1. mod-severe obtundation
2. MM pale
3. 2-3s CRT
4. HR: increased/ poss. dec in cats
5. Weak/poor pulses
6. cool extremities
   ++ decreased BP

Question 23

perfusion parameters of moderate vasodilatory shock

Answer 23

1. Mod - severely obtunded
2. MM hyperaemic
3. <1sec CRT
4. HR: inc/ poss dec. in cats
5. Bounding to normal
6. warm extremities
   ++ systolic and diastolic BP decreased

Question 24

Describe the pulse quality and blood pressure in severe shock (vasoconstrictive or dilatory)?

Answer 24

non-palpable pulses, unable to read BP

Question 25

list 3 isotonic crystalloids

Answer 25

- 0.9% NaCl - Compounded sodium lactate (Hartmanns) - Plasmalyte-148

Question 26

shock volume for IVFT in dogs

Answer 26

20ml/kg

Question 27

shock volume for IVFT in cats

Answer 27

15ml/kg

Question 28

adverse effects of crystalloid fluids

Answer 28

- large volumes required and pattern of distribution may result in haemodilution effects + interstitial oedema - rapid IV crystalloid fluid therapy may cause damage to the inner lining of blood vessels and perpetuate inflm and endothelial ‘leakiness’--> further tissue oedema - potentially harmful - lung dysfunction dt 75% of dose ending up in the interstitium

Question 29

list 3 colloid solutions

Answer 29

- albumin - voluven/volulyte - gelofusine

Question 30

indications to use colloid solutions

Answer 30

patients with low COP (esp. those w/ acute protein losses)

Question 31

synthetic colloid fluid dose

Answer 31

5ml/kg | max dose over 1 day is 20ml/kg for dogs

Question 32

adverse effects of colloids

Answer 32

- possible inc. risk of AKI, platelet and coag. dysfunction - anaphylaxis + hypersensitivities - artificial inc. USG, Total plasma protein

Question 33

max dose of hypertonic saline

Answer 33

6ml/kg over 5 min

Question 34

uses of hypertonic saline

Answer 34

large animals in shock whilst allowing time for large volumes of crystalloids to be infused

Question 35

indicators to use a vasopressor

Answer 35

1. Patient received 50% BV IVFT and signs of vasodilatory shock 2. Patient received full BV IVFT and still hypotensive 3. Evidence of fluid overload (jug. distension, serous nasal discharge, chemosis) + hypotensive 4. Septic shock suspected

Question 36

weak-moderate vasopressor

Answer 36

dopamine

Question 37

strong vasopressors eg.

Answer 37

- norepinephrine - phenylephrine - epinephrine (adrenaline) - vasopressin

Question 38

CS of 10-12% dehydrated

Answer 38

marked prolongation of skin tent, dry mm, dry conjunctiva and sunken eyes. Animal may also start to show signs of hypovol.

Question 39

CS of 5% dehydrated

Answer 39

minimal amount of dehydration detected on PE; tacky mm, reduced tear film

Question 40

CS of 6-9% dehydrated

Answer 40

delayed skin tent, tacky-dry mm, reduced tear film

Question 41

which increases first with severe dehydration - urea or creatinine?

Answer 41

urea

Question 42

DDx for inc. PCV

Answer 42

splenic contraction during stress, dehydration

Question 43

Stepwise Qs to ask when formulating a fluid plan?

Answer 43

1. Shock - type and severity 2. Dehydration - % 3. Lyte imbalances 4. Metabolic acid-base 5. Other: anaemia, hypoproteinaemia, XS losses 6. Predisposition to overload - anuric/oliguric w/ AKI, cardiac disease 7. Route and timeframe

Question 44

Steps to estimate the deficit volume

Answer 44

BW X % dehydrated = L Rate: 6-12hr w/ acute dehydration (dog) and otherwise healthy, 12-24hr if CDV/renal disease Cats 8-24hrs

Question 45

Maintenance rate of small dog

Answer 45

4ml/kg/hr

Question 46

Maintenance rate of large dog/cat

Answer 46

2ml/kg/hr

Question 47

estimate ongoing abnormal losses w/ severe vomiting (1x/hr)

Answer 47

1-2x maintenance

Question 48

estimate ongoing abnormal losses w/ moderate vom (q6h)

Answer 48

0.5xmaintenance

Question 49

vom once very 12hrs ongoing losses rate?

Answer 49

0.25 maintenance

Question 50

examples of isotonic fluid loss

Answer 50

V+/D+ PU Fluid accumulation in third space - GIT space, peritoneal, pleural

Question 51

example of hypotonic loss

Answer 51

- secretory D+ eg. neonatal D+ in calves | - third spacing of water into the GIT after ingesting hyperosmolar material ie salt/paintballs

Question 52

example of hypertonic losses

Answer 52

patients w/ hypoA and aldosterone deficit --> lack of ability to retain sodium and conserve water --> obliate PU and more rapid dehydration if that patient is also anorexic, + V/D+ (dt reduced circulating cortisol)

Question 53

indications to use 0.9%NaCl

Answer 53

- hypercalcaemia | - metabolic alkalosis (dilutes XS bicarb w/ chloride)

Question 54

indications to use LRS

Answer 54

- correcting metabolic acidosis

Question 55

indications to use plasmalyte-148

Answer 55

- hypomagnesaemia | - severe liver dysfunction unable to metabolise lactate - as uses gluconate and acetate as bicarb precursor

Question 56

how does 0.45% NaCl + 2.5% dextrose behave?

Answer 56

Half strength sodium’ (half normal ECF sodium conc.) about half the V of fluid being given will act like replacement fluid for ECF and half will behave as free water once the glucose molecules are metabolised.