WUFluid Therapy for the Bovine Patient

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Fluid Therapy for the Bovine
Patient
Brad Jones DVM, MS
GPVEC and PPVM UNL
Objectives:
• Understand the basic considerations of fluid administration
as it relates to route, type and amount administered.
• Understand differences in fluid administration for both the
neonate and the adult bovine.
• Establish a minimum data base for development of an
appropriate fluid treatment plan for the bovine neonate.
• Formulate a treatment plan as it relates to fluid
administration for a calf presenting with neonatal diarrhea;
addressing four core concepts of shock/dehydration,
acidosis, potassium status, energy and prognosis (FPT).
• Provide basic conversions to accomplish “fluid
compounding” for practical use and fulfillment of the
rotation quiz.
Fluid Administration: Route
• Fluid administration occurs via enteral and
parenteral routes.
– Enteral routes should be used in adult cattle when
possible based on management and cost of IV
administration.
– IV administration
• Complete replacement is more practical in neonates.
• Hypertonic solutions can augment enteral routes
Fluid Administration: Type
• Composition of fluid to be administered
depend on:
– Route
– Electrolyte status
– Acid/Base status
• Considerations include:
– Water/Isotonic/hypertonic
– Milk versus electrolytes
– Alkalizing? Type?
Fluid Administration: Amount
• Basic concepts of fluid correction are centered
around these three basic parameters in all
species:
– Maintenance
• cow versus calf
– Dehydration
– Ongoing loss.
• Rate of administration based on the size of the
animal can be quite rapid but should not exceed
80mls/Kg in the first hour or 30mls/Kg chronically
in calves. Cows should not exceed 40mls/kg/Hr.
Neonate or Adult?
• Several differences are noted between the
neonate and the adult with regard to fluid
administration.
– Size as it relates to practicality an cost of
administration
– Acid base status
– Status of gastrointestinal tract
• Calves versus cow
• Functional?
Fluid administration: Neonate
• Five core concepts:
– Treatment:
•
•
•
•
Dehydration/Shock
Hyper/Hypokalemia
Energy
Acidosis: BD or SID
– Prognosis
• FPT
• Physical exam
• Response to initial
treatment
Dehydration
• Calculated based on
– Eye positon
– Skin turgor
– Volume = % dehydration x BW Kg
• Treatment is generally a
combination of enteral
and parenteral
administration.
– Oral fluids
• Milk and electrolytes
– IV fluids
• Isotonic crystalloids
• Hypertonic crystalloids
Compiled from Howard, Smith, Blood et. al.
Potassium
• Acidosis may yield marked hyperkalemia
• Total body stores depleted
– Diarrhea
– Renal excretion due to hyponatremia
– Anorexia
• Rapid administration can be lethal!
• The sick dehydrated adult cow generally will
benefit from potassium supplementation.
Temperature
• In my hands calves with diarrhea are rarely
exhibit pyrexia; either normothermic or
hypothermic.
– Hypothermic?
• Hypoglycemia
• Endotoxemia
– General indication for Dextrose administration
• 2.5% to 5% solution
• Other benefits?
• Give to all?
Acidosis
• Two concepts and both appear
effective in treatment.
– SID
– H-H: Acidosis as measured by
CO2 or bicarbonate to
determine base deficit
• mEqNaHCO3 Needed =
(BW kg) ( 30 – TCO2) (.6)
–
–
*30-TCO2 is the Base Deficit
0.6 is the coefficient of extracellular fluid in
calves
• Numerous ways to correct
– Isotonic sodium bicarbonate
– Hypertonic sodium
bicarbonate
– Crystalloids with added
hypertonic sodium bicarbonate
Assessment of Acidosis
• Two common ways to
assess base deficit;
– TCO2
– Demeanor score
Base
Deficit
(Meq)
Demeanor Score
(< 8 days of age)
Base
Deficit
(Meq)
Demeanor Score
(> 8 days of age)
Standing, good suckle
1
0
Standing, good suckle
1
5
Standing, weak suckle
2
5
Standing, weak suckle
2
10
Sternal recumbency
3
10
Sternal recumbency
3
15
Lateral recumbency
4
10
Lateral recumbency
4
20
Naylor
Abaxis iSTAT 1
Fluid Replacement Considerations
• Type?
– Crystalloids
• Hypertonic or isotonic?
• Source?
– Commercial or compounded?
• Amount?
– Dehydration, Maintenance,
ongoing loss
• Acidosis?
– Assessment via demeanor score,
TCO2
• Potassium?
– Serum versus total body
• Dextrose?
– Temperature; Mentation and
suckle reflex probably the result or
acidosis.
Word on Prognosis
•
For the neonate assessment geared
to:
1.
2.
3.
4.
5.
Definitive problem list; “diarrhea or
not”
Concurrent conditions to diarrhea.
Passive Transfer Status
Energy Status
Severity of acidosis
Fluid Therapy in Adults
Differences from the neonate?
1. Conditions that require
administration are
different.
2. Tend to suffer from
alkalosis thus require
acidifying solutions.
3. As discussed amount of
fluid is significant.
4. Ruminant digestive
system.
Clinical presentation in the
adult?
1. Most likely dehydration
not overt shock.
2. Negative base excess.
–
–
Mature cattle twice as likely
to be alkalotic.
Exceptions rumen acidosis,
pneumonia and diarrhea.
3. Very often hypochloremic,
hypokalemic (at least total
body stores) and need to
consider hypocalcemia.
Fluid Considerations: Type
• Oral solutions
– Water
– Isotonic solutions
• IV solutions
– Crystalloids
• Isotonic (generally NaCl
with additional KCl)
• Hypertonic NaCl
– Calcium containing
solutions
• Acidosis corrected in
similar fashion with the
exception: conversion
factor of extracellular
volume is 0.3.
meq Bicarb=BW (kg) x 30 – TCO2 (.3)
Fluid Considerations: Amount
• Maintenance fluids
– Remember lactation but
sick cows usually not an
issue.
• Ongoing losses
– Often less of an issue
than in the neonate.
• Dehydration
Constable PD. JAVMA 1998: 212:991-996
% Dehydration
0 2 4 6 8
10
12
14
Eyeball Recession (mm)
0 1 2 3 4
6
7
8
Skin-Tent Duration (s)
2 3 4 5 6
7
8
10
Fluid Considerations: Route
• IV fluids
– Crystalloids
• Usually NaCl with added
KCl
– Hypertonic saline
• Dose is 4-5 mls/kg BW (23/# BW) over 5 minutes.
• Concurrent oral fluids,
water and/or additional
electrolytes should be
administered.
• Oral Fluids
– Abomasal atony and pH
not an issue versus
calves
– “cut off” for oral fluids
alone: 8% dehydration
• Not a hard rule and based
on clinical evaluation.
Administration Rate
• Limit to 40ml/Kg/hour to
adult cattle with normal
cardiovascular function.
– One 14 gauge catheter
20ml/kg/hour in a 500Kg
cow.
– Potassium added at rate of
25 mEq/liter will not
excede 0.5mEq/Kg/hr
– Can add 500ml of 23%
calcium borogluconate per
20 liters
Fluid Compounding
• Conversions:
– % solution to mg/ml?
Move decimal place one
to the right.
– % solution to
gram/100ml is as read.
• Bicarbonate conversion:
– 8.4% = 1 mEq/ml
– 5% = 0.6 mEq/ml
– 1.3% (isotonic) =
0.15 mEq/ml
Resources for this presentation:
•
•
•
•
•
•
•
•
•
•
Fluid Therapy in Calves. Smith, Berchtold. Vet Clin Food Anim 30 (2014) 409-427.
Constable PD. JAVMA 1998: 212:991-996
Fluid Therapy in Mature Cattle. Roussel. Vet Clin Food Anim 30 (2014) 429-439.
Hypokalemia Syndrome in Cattle. Sattler, Fecteau. Vet Clin Food Anim 30 (2014)
351-357.
D-Lactic Acidosis in Neonatal Ruminants. Lorenz, Gentile. Vet Clin Food Anim 30
(2014) 317-331.
Acid Base Assessment. Constable. Vet Clin Food Anim 30 (2014) 295-316.
Treatment of Calf Diarrhea: Oral Fluid Therapy. Smith. Vet Clin Food Anim. 25:1
(2009) 55-72.
Treatment of Calf Diarrhea: Intravenous fluid therapy. Berchtold. Vet Clin Food
Anim. 25:1 (2009) 73-100.
Veterinary Medicine a textbook of the diseases of cattle, sheep, pigs, goats and
horses 9th ed. Radostits, Gay, Blood, Hinchcliff. Saunders 2000.
Large Animal Internal Medicine 4th ed. Smith. Mosby 2009.
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