Ex 3 - Support during anesthesia (fluids, electrolytes, & recovery) Flashcards
What is the Total Water Volume (TWV) in a patient?
60-80% of BW
How is the TWV in a patient divided?
40% = Extracellular
- 10% = intravascular
- 30% = interstitial
60% = Intracellular
Dehydration assessment involves mostly ______ water volume.
extracellular
Hypovolemia assessment involves mostly _____ water volume.
intravascular
Treatment for Dehydration
Crystalloids!
Restore water and electrolytes to the entire Extracellular Space (volume)
What are 4 examples of crystalloids used?
- Lactated Ringer Solution (LRS)
- Normosol
- Plasmalyte
- Physiologic Saline (0.9% NaCl)
*We use LRS most often
Treatment for Hypovolemia
Blood volume support!
- Crystalloids
- Colloids
- Blood products
Routes for fluid administration
- Which do we use most often during anesthesia?
- What do we use when we can’t get IV access?
- What do we use for long-term? (slow route)
- IV
- IO
- Sq
How much fluid to administer - what is the plan? (3 points)
- Restore deficits
- Maintain normal ongoing loss
- Treat abnormal losses
- Restore Deficits
The deficit is determined before anesthesia from dehydration status, hypovolemia, and 3rd space loss assessment
How much LRS would be required for a 40 kg Rottweiler with 10% dehydration
Required LRS (L) = 10 % of BW (40kg)
10% of BW = 4L
- Maintain normal ongoing loss
Normal ongoing loss depends on caloric expenditure, urine & fecal production and evaporation
What is the average Daily Water Intake?
1-5 ml/kg/hr (20-120 ml/kg/day)
High metabolic needs for smaller animals (cats > dogs)
- Treat Abnormal Losses
What to consider?
If possible, measure it, but most times is an estimate
- evaporate from dry anesthesia gas
- evaporate from open cavities
- blood loss during sx
- 3rd space loss
- diuresis
- D and V (uncommon)
What is the guideline that is used for crystalloid administration in anesthetized patients?
1-10 mL/kg/hr
Fluid boluses
- What is the conservative crystalloid dose?
- What is the shock fluid bolus?
- 10-20 ml/kg
2. 50-100ml/kg (don’t give all at once –> better to start with conservative and add more)
What are colloids used for?
Which one do we use often at VTH?
Used to restore blood volume and maintain oncotic pressure
Hetastarch
What is the oncotic pressure?
It is the force generated by the plasma proteins to maintain water in the vascular space
Normal capillary OP = 20-22 mmHg
What are 5 advantages of Colloids?
- Stay in the vasculature longer (6-48 hr)
- Relatively economical
- Long shelf life
- Increases blood volume rapidly
- May prevent edema
What are 6 disadvantages of Colloids?
- Hemodilution
- Coagulopathies
- Limit daily dose to 20 ml/kg/day
- Anaphylactic reactions
- Fluid overload
- Acute renal disease
Name the 6 Blood Products we use
- Fresh Whole blood
- Stored Whole blood
- Stored RBC
- Plasma
- Platelet-rich plasma
- Oxyglobin (purified Hb)
What does Blood Typing identify?
RBC Antigens
What does Cross Matching (major and minor) detect?
Ig from recipient or donor
What is fresh WB?
Original blood (fresh) from donor.
Contains: RBC, platelets, proteins, coagulation factors