Fluid Therapy

Question 1

Fluid distribution

Answer 1

total water = 2/3 body weight

plasma = 1/4 extracellular fluid = 1/10 total body water

Question 2

Blood volume

Answer 2

dog = 88ml/kg

cat = 66ml/kg

Question 3

Aims of fluid therapy (6)

Answer 3

maintenance of normal function
improvement of organ function
correction of electrolyte disturbances
correction of hypovolemia
correction of acid-base disturbances
total parenteral nutrition

Question 4

Assessing hydration status

Answer 4

pulse quality
CRT
eye position
mm
bp
skin tent
hr
demeanor

Question 5

Fluid deficit

Answer 5

<5% - no signs
5-6% - tacky mm, thirst
6-8% - skin tenting, sunken eyes
8-10% - increased pulse rate, cold peripheries
10-12% - pulses weak
12-15% - collapse

Question 6

maintenance

Answer 6

2.5ml/kg/hour = 60ml/kg/day

Question 7

total deficit

Answer 7

% fluid deficit + losses

Question 8

fluid given

Answer 8

daily maintenance = total deficit

acute - 1/2 deficit in first 1-2 hours then rest in 24-48 hours
chronic - replace over 3-4 days
shock - 60-90ml/kg/hour for max 1 hour

Question 9

anaesthesia fluid rates

Answer 9

dog - 5-20ml/kg/hour
cat - 3-9ml/kg/hour

Question 10

crystalloids

Answer 10

electrolytes in water, mimics plasma, hypotonic, isotonic, hypertonic

lactated ringers - isotonic - short term therapy only

hypotonics - eg. 0.18% NaCl

Hypertonic - saline - draws fluid from interstitial space

Question 11

colloids

Answer 11

exert colloid osmotic pressure - support circulating blood volume

eg. hetastarch

Question 12

blood products

Answer 12

whole blood, pure RBCs, oxyglobin solution

Question 13

sensible and insensible losses

Answer 13

maintenance

sensible - easily measureable - eg. urine
insensible - harder to measure - eg. fluid lost in respiration