Fluid Therapy 1 Flashcards
What % of TBW does fluid make up?
60%
What % of TBW makes up intracellular vs. extracellular %?
Intracellular: 30-40%
Extracellular: 20-30%
What are 5 indications for fluid therapy?
Decreased intake Dehydration Decreased circulating volume Need for overhydration Miscellaneous
What are 3 reasons for decreased intake of water?
Disease: anorexia, gastric reflux
Inability to ingest water: dysphagia, esophageal obstruction, neurologic dysfunciton
Lack of availability: freezing water
What are the 4 types of shock?
Hypovolemic shock
Vasculogenic shock
Maldistributive shock
Cardiogenic shock
In what situation would you need to overhydrate a horse?
Intestinal impaction- increases fluid flow to intestinal lumen and softens stool to allow for easier passage
What are 7 clinical signs that indicate the need for fluid therapy?
Skin turgor Mucous membranes Urine production Sunken eyes Depression, muscle weakness Heart rate Decreased jugular distensibility
At what % of dehydration is skin turgor often seen?
8-10% dehydration you begin to notice this CS
Where should you check skin turgor in adult horses vs. foals?
Adult: neck
Foal: eyelid
What is the normal skin tent time?
<1 sec
At what % are dry MM noticed in equine?
5-7% dehydration
What is noticed about the urine of a dehydrated patient?
Decreased urine output and increased urine specific gravity
What species are sunken eyes most commonly observed in?
Ruminants-not common to see in equine
What is noticed about the heart rate in a dehydrated horse?
Tachycardia- one of the first parameters to change
What are 6 laboratory indicators of dehydration?
PCV TP BUN/Crea Albumin Lactate Urinalysis
What can mask anemia in an equine patient causing underestimation of severity of the disease?
Splenic contraction
What will you expect the TP to do as an animals %dehydration increases?
TP should increase
What can hypoproteinemia do to your estimate of % dehydration?
Underestimate degree of dehydration
What should you keep albumin above?
1.5 g/dL
What is the only possible cause of hyperalbuminemia?
Dehydration
What are 6 CS associated with hypovolemic shock?
Prolonged CRT Decreased jugular filling Tachycardia Decreased pulse pressure Cold extremities Decreased skin turgor
What % dehydration is the following patient?
A horse is presented to you with the following:
Skin tent (s): 2 seconds
MM: slightly tacky
CRT: normal
HR: normal
Decreased urine output
5%
What % dehydration is the following patient? A horse is presented to you with the following: Skin tent (s): 4 s. MM: tacky CRT: 2-3 s. HR: 40-60 bpm Decreased arterial BP
8%
What % dehydration is the following patient? A horse is presented to you with the following:
Skin tent: 5 sec. +
MM: DRY
CRT: > 4 sec.
HR: 60 BPM+
Reduced jugular fill, barely palpable pulse
10-12%
What % dehydration is the following patient? A horse is presented to you with the following:
Obvious sunken eyes and in a state of shock
12-15%- on the verge of death
What are the 7 routes of fluid administration?
Oral IV SubQ Intra-peritoneal Rectal Intraosseous Intra-cecal
What is the most common route of administration of oral fluids in a horse?
Nasogastric tube for fluid administration
How many L can be administered at once via oral route?
6-8L should be targeted at once (can get up to 12-16 L)
What is the fluid transit time from the stomach?
<30 min
What complication commonly benefits from oral administration the most?
LI impactions
What is the major contraindication of oral fluid administration?
Presence of gastric distention, reflux and ileus
What is the second most common route of fluid administration?
IV route
What are the four sites of IV placement?
Jugular vein
Lateral thoracic vein
Cephalic vein
Saphenous vein
What direction should the catheter be placed?
TOWARDS THE HEART
What side of the horse are intra-peritoneal fluids administered?
Dorsal aspect of left flank
What is a major advantage of intra-peritoneal fluids?
Potentially large volumes at a rapid rate
How should you position a horse receiving rectal fluids?
Horse should stand on an incline with head/forelimbs lower than hind end-avoids evacuation reflex of terminal small colon and rectum
What is the major concern of intra-osseous fluid administration?
Rate at which the fluids can be administered
What is the rate of intra-oseous fluid administration limited by?
Size of needle-maximum administration is 2L/hr
What is the rate limiting step of fluid administration?
narrowest diameter in system- 10 G is the rate limiting catheter size
What is the length and flow of a 14 G catheter?
Length: 5.25 in.
Flow: 13.1 L/hr
What is the flow of a 12 G catheter?
26.9 L/hr
What is the flow of a 10 G catheter?
36.5 L/hr
What is the typical STAT IV set?
8; above horse with 28L/hr gravity flow capacity
What is the typical rate of a macrodrip set in equine?
10-15 drops/mL
What type of material makes up long term catheters?
Polyurethane or silicone
What type of material makes up short term catheters?
Teflon and polyethylene
What is the maximum time period that short-term catheters can be kept in?
72 hrs.
The rate of thrombosis depends on what 6 factors?
systemic state of animal
stiffness of catheter- stiffer=more thrombogenic
Size of catheter- larger=more thrombogenic
length of catheter- longer=more thrombogenic
material of catheter- most thrombogenic (polypropylene) least thrombogenic (polyurethane/mila)
Vessel trauma
What is the typical acid-base disturbance in horses?
Metabolic acidosis
Typically have loss of K and Ca
What 3 factors determines the choice of fluid used?
Fluid type
fluid tonicity
fluid effect on acid/base status
What are the most common type of fluids used in equine medicine?
Crystalloids
What are examples of crystalloid solutions?
LRS Saline Normosol (M/R) Plasmalyte Dextrose solutions Bicarbonate solution
What % sodium is in the following solutions: Normal saline Half-strength saline Twice stregnth saline Hypertonic saline
- 9%
- 45%
- 8%
- 2%
When are colloid solutions used?
Increase oncotic force within IV space to retain fluid within that space
What specific case are colloids commonly used?
Hypoproteinemia
Dextran, hetastarch, plasma, serum are used
What is the most common fluid used in equine medicine?
LRS
What is the most common reason for hypertonic saline use?
Emergency resuscitation in hypovolemia
What site should hypertonic saline be administered?
Jugular catheter
What is the MOA of hypertonic saline?
fluid shift from intracellular space into ECF space associated w/ increased tonicity
What is the direct effect of hypertonic saline?
triggering central brain receptor mechanism
What is the overall effect of hypertonic saline?
Improvement in CO, MABP urine production and decrease in systemic vascular resistance
- do so by increasing preload and decreasing afterload
What can be a major complication of hypertonic saline administration?
Uncontrolled hemorrhage due to the improved CO
Can dehydration be a contraindication for hypertonic saline administration?
Not dehydration alone. However- hypertonic dehydration state can be contraindicated for hypertonic saline administration due to the increased swelling in the brain
What type of inotropic effect does hypertonic saline have?
Negative inotrope-cardiotoxic
T/F: shocky patients are severely dehydrated
FALSE- shocky patients are severely hypovolemic
