Fluid therapy in cattle Flashcards
Hypertonic saline exerts its beneficial effect by
rapid plasma volume expansion.
Hypertonic saline IV dosage adult cattle
7.2% NaCl 4-5 ml/kg (2400 mOsmol/L) IV over 4-5 minutes and should immediately be provided with access to min 20- 40L drinking water.
If they don’t drink, then pump 20L into the rumen.
e.g. 600 kg cow gets 3L HS i.v.
Hypertonic saline IV dosage calves
4-5 ml/kg ml 7.2% NaCl
e.g. 50 kg calf gets 250 ml IV
and 2-3 L isotonic alkalinizing oral electrolyte solution offered PO
Main contraindication for hypertonic saline admin.?
hypernatremia (hyperosmolality),
especially renal failure cases
Indications for IV hypertonic saline therpay in ruminants. (3)
> 8% dehydration
endotoxemia
hemorrhagic shock
How would you mix a homemade hypertonic saline solution?
Products are available commercially.
Or formulate by adding 72 g of NaCl to 1L distilled water.
What do you need to assess before starting fluid therapy?
- Does the presumptive diagnosis include an acidosis or alkalosis?
- How severe dehydration %?
- Fluid composition? Isotonic or some hypertonic solution
What IV solution would you choose for a metabolic acidosis and what would you choose for dehydration therapy?
5,4% NaHCO3 (baking soda) for metabolic acidosis
+ Need to calculate base requirements in case of metabolic acidosis.
7,2% NaCl for dehydration therapy
IVFT neonates vs adults
Mature cattle twice as likely to be
alkalotic than calves.
How to calculate base requirements in case of metabolic acidosis.
Acidosis corrected with conversion factor of extracellular volume: 0.3.
Base deficit * 0,3 * BW(kg)
Bicarbonate conversion:
* 8.4% = 1 mEq/ml
* 5% = 0.6 mEq/ml
* 1.3% (isotonic) = 0.15 mEq/ml
Maintenance fluids formula for adult cows:
100 ml/kg BW or
3,5-5% of BW
dehydration % “cut off” for giving oral fluids alone:
8% dehydration
Not a hard rule and based on clinical
evaluation.
IV Administration Rate Limit
40ml/Kg/hour to adult cattle with normal cardiovascular function.
One 14 gauge catheter only allows 20ml/kg/hour in a 500Kg cow.
Therefore, in most situations intravenous fluids can be safely administered to mature cattle through a 14-gauge catheter as
quickly as they will flow by gravity.
Assessment of dehydration level by
skin tenting and eye recession.
Clinical symptoms that help evaluate dehydration in calves.
diarrhea
depression, weakness
skin tenting prolonged
sunken eyes
prostration
tacky or dry mucous membranes
cool extremities
Most common reason for metabolic acidosis in calves?
loss of bicarbonates with diarrhea
Fluid therapy options in case of metabolic
acidosis.
Alkalizing solutions: bicarbonates, lactate, acetate, gluconate and citrate – bind hydrogen ions.
Available in the Estonian market: Ringer-lactate, 4,2% and 8,4% bicarbonate solutions, Ringer acetate.
Isotonic bicarbonates most suitable for diarrheic calves.
250 ml 8.4% bicarbonate solutions mixed with 5 l of isotonic solution.
8.4% bicarbonate solutions should not be administered alone!
Acetate and lactate metabolize into bicarbonates.
Ringer-lactate consists of L- and D-lactate!
Dextrose solutions for newborn calves in case of hypothermia.
Calculation of base deficit (BD)
Requirement for total alkalizing agent (mEq) = base deficit (mEq/l) x 0,3 x BW.
For calves use conversion factor 0,6 because most of the BW is extracellular
fluid.
If not possible to measure, use base deficit default 10 mEq/l.
Rule of thumb:
Recumbent calf - dehydration 12-15%, BD 15-20 mEq/l.
Weak calf – dehydration 8-12%, BD 15 mEq/l.
Ambulatory calf - dehydration 5-8%, BD 5- 10 mEq/l.
Base deficit rules of thumb for calves in varying states of dehydration.
Rule of thumb:
Recumbent calf - dehydration 12-15%, BD 15-20 mEq/l.
Weak calf – dehydration 8-12%, BD 15 mEq/l.
Ambulatory calf - dehydration 5-8%, BD 5- 10 mEq/l.
Requirement for total alkalizing agent (mEq) = base deficit (mEq/l) x 0,6 x BW.
For calves use conversion factor 0,6 because most of the BW is extracellular
fluid.
Example calculation for base deficit calf.
50 kg calf
use base deficit default 10 mEq/l
Requirement for total alkalizing agent (mEq) = base deficit (mEq/l) x 0,6 x BW.
10 x 0,6 x 50 = 300 mEq
1 g = 12 mEq of bicarbonates
1 litre of 4,2% Na-bicarbonate solution contains 42 g of bicarbonates = 504 mEq
We need around 0,6 litres of this fluid.
1,3% bicarbonate solutions = 13 g in 1 litre or 156 mEq/l so in that case, 2 litres of isotonic Na-bicarbonate solution is needed.
State of potassium in acidosis?
It has been generally accepted that acidosis results in hyperkalemia because of shifts of potassium from the intracellular to the extracellular compartment.
What molecule is important in potassium transport into cells?
glucose
So in hypoglycemic calves with diarrhea and thus dehydration induced hyperkalemia - administer glucose as well, to get that K back into the cells.
calf oral electrolytes or IV?
What conditions cause alkalosis in cows?
Almost every condition associated with loss of appetite and gastrointestinal stasis.
Vagal nerve problems
Torsion of the intestine, intussusception
Displacement and/or torsion of the cecum
Abomasal displacement and torsion
Traumatic reticulitis
Abomasal ulcers
Peritonitis
Renal failures
Rumen indigestion and putrefaction, atony
