Fluid Therapy

Question 1

Define hypovolaemia.

Answer 1

A state of decreased intravascular volume.

Question 2

Define dehydration.

Answer 2

Excessive loss of body water from the extravascular compartment.

Question 3

What is the other term for shock?

Answer 3

Tissue hypoperfusion.

Question 4

What parameters are affected by hypovolaemia?

Answer 4

HR, pulse quality, MM colour, CRT, BP and mentation

Question 5

What are normal canine parameters?

Answer 5

HR = 60-120
Pink MMs
CRT = <2 secs
Systolic BP = >90

Question 6

What parameters are affected by dehydration?

Answer 6

MM moistness, skin turgor, weight, globe position

Question 7

What is the advantage of isotonic crystalloids and give two examples of solutions?

Answer 7

Mimic intravascular electrolyte concentration (high Na, low K)

0.9% NaCl, Hartmann’s

Question 8

What makes colloids different to crystalloids?

Answer 8

Colloids contain large molecules (either natural or artificial) that increase colloid osmotic pressure.

Question 9

What is the potential advantage of colloids?

Answer 9

They stay in the intravascular space for longer, so a smaller volume of fluid can be used for volume resuscitation.

Question 10

What conditions need to be considered before prescribing fluid therapy?

Answer 10

Cardiac disease/heart failure
Renal failure
Respiratory disease

Question 11

What are the symptoms of volume overload?

Answer 11

Pulmonary oedema (tachypnoea, dyspnoea, crackles)
Venous engorgement
Peripheral oedema formation / chemosis
Cavitary effusions

Question 12

Name the 5 routes of fluid administration.

Answer 12

Per os
Subcutaneous
Intravenous
Central venous access
Intraosseous

Question 13

What components make up the minimum database?

Answer 13

PVC, TS, urea, glucose, lactate, blood smear

Question 14

How do we interpret PCV and TS readings?

Answer 14

Should be interpreted together and in context of the clinical findings
Changes in PCV and TS are not diagnostic!

Question 15

What do high and low urea readings indicate in the minimum database?

Answer 15

Increases may be pre-renal, renal or post-renal

Low urea can be due to severe hepatic dysfunction

Question 16

In what patients should we check blood glucose?

Answer 16

Patients with altered mentation
Patients experiencing seizures
Patients with distributive shock
Paediatric patients
Patients with history compatible with diabetes mellitus

Question 17

If a patient presents with high blood glucose, which measurement would be added to the minimum database?

Answer 17

Serum or urine ketones.

Question 18

What can lactate levels indicate about a patient?

Answer 18

Levels increase when a patient is in shock - a marker of tissue hypoxia

Question 19

What are we looking for in a blood smear examination?

Answer 19

Regenerative/non-regenerative anaemia
RBC morphology changes]
Circulating white blood cell numbers
Platelet numbers
Blood-borne parasites?

Question 20

What are the common causes of hyperkalaemia (increased potassium)?

Answer 20

Urethral obstruction
Uroabdomen
Hypoadrenocorticism
Renal failure

Question 21

What is the treatment for hyperkalaemia (increased potassium)?

Answer 21

IVFT - an isotonic crystalloid
Calcium gluconate
Glucose +/- soluble insulin

Question 22

What are the common causes of hypokalaemia (decreased potassium)?

Answer 22

Vomiting and diarrhoea
CKD, post-obstructive diuresis, diuretics
Fluids containing insulin/glucose
Anorexia/inappetence
Long-term IVFT with low K concentration

Question 23

How do we treat hypokalaemia (decreased potassium)?

Answer 23

Potassium supplementation
IV in saline / Hartmann’s (never bolus)
Oral supplementation for chronic disease

Question 24

How are chloride and sodium levels related and how do we determine if a change in chloride level is significant?

Answer 24

Should be in a 1:1 ratio

Chloride needs to be ‘corrected’ to determine if changes are proportionate or disproportionate

Question 25

What are the causes of corrected hyperchloraemia?

Answer 25

May be artifact
Iatrogenic
Associated with acid-base disturbances

Question 26

What are the causes of hypochloraemia?

Answer 26

Iatrogenic

Loss of chloride in excess of sodium (e.g. pure gastric vomiting or excessive sweating in horses)

Question 27

What are the clinical signs and treatment of hypocalcaemia?

Answer 27

Tetany, panting, hyperthermia, facial pruritus

Treatment = calcium gluconate IV

Question 28

What are the clinical signs and treatment of hypercalcaemia?

Answer 28

PUPD, anorexia, lethargy, depression, shivering, twitching, vomiting
Treatment = directed at underlying cause and correction of dehydration (severe = salmon calcitonin or bisphosphonates considered)