Fluid Therapy Flashcards
What is the first question to ask concerning fluid therapy?
Does the patient need fluids?
With what percent dehydration can you see the following:
- 1-3 sec skin tent
- Most to slightly tacky MM
- Normal CRT
- Normal HR
- Decreased urine output
5 % dehydration
With what percent dehydration can you see the following:
- 3-5 sec skin tent
- Tacky MM
- Often 2-3 sec CRT
- 40-60 beats/min HR
- Decreased arterial BP
8%
With what percent dehydration can you see the following:
- 5 or more sec skin tent
- Dry MM
- Often >4 sec CRT
- 60 beats/min HR or greater
- Reduced jugular fill
- Barely detectable peripheral pulse
- Sunken eyes
10-12%
With what percent dehydration can you see the following:
- 5 or more sec skin tent
- Dry MM
- Often >4 sec CRT
- 60 beats/min HR or greater
- Obvious sunken eyes
- Obvious shock
12-15%
At what percent dehydration is death imminent?
15%
Horses can have high PCVs under stress due to what?
Splenic contraction
Do you want to correct a fluid deficit slowly or rapidly with large animals?
Rapidly (within an hour)
What are 6 possible routes of fluid administration?
- SQ
- PO
- IV
- IO
- Per rectum
- IP
What are 3 important factors used in making decisions concerning fluid therapy?
- Rate of flow required
- Minimize thrombogenicity
- Vessel sparing
What is the most commonly used route of fluid administration in horses?
PO
What is one of the most commonly used set ups for IV fluid administration in horses?
STAT IV set
What are 4 components of the STAT IV set?
- Gravity flow
- 4 x 5 L bags
- Large bore coil system
- 8’ from base of heart
What are 2 things the rate of flow of a STAT IV set determined by?
- Size of tubes
- Height from heart
What is the flow rate of a 10 G catheter?
36.5 L/hr
What is the flow rate of a 12 G catheter?
26.9 L/hr
What is the flow rate of a 14 G 5.25” catheter?
13.1 L/hr
What are 4 factors the flow in a free flow system is determined by?
- Height of horse (heart)
- Size of all tubing in system
- Length of system
- Fluid viscosity
What are 4 possible complications that can be seen with the use of catheters?
- Thrombosis
- Septic phlebitis
- Perivascular leakage/cracking
- Breakage of catheter
Perivascular leakage/cracking can lead to what 3 possible complications?
- Abscessation
- Neurologic dysfunction
- Sloughing
What are 2 factors on which to base the decision of what electrolytes to use?
- Based on disease
- Based on animal
What are 4 characteristics of fluids?
- Tonicity/osmolality
- Composition
- Effect in organism
- Category/type
What are 3 variations of tonicity?
- Isotonic
- Hypertonic
- Hypotonic
What are 5 significant electrolytes that should be evaluated?
- Na+
- K+
- Ca++
- HCO3-
- Lactate
What are 2 main types of fluid?
- Colloid
- Crystalloid
What are 3 examples of crystalloids?
- Saline
- LRS, Normosol, Plasmalyte
- Dextrose
What are 3 types of saline crystalloids?
- Isotonic
- Hypotonic
- Hypertonic
What percentage saline is isotonic?
0.9%
What percentage saline is hypotonic?
0.45%
What are 2 variations of hypertonic saline?
- Twice strength: 1.8%
- Hypertonic saline: 7-7.4%
What is the most common fluid used for horses?
LRS
What are 3 percentage variations of dextrose?
- Isotonic: 5%
- Half-strength: 2.5%
- Hypertonic: 50%
Which percentage of dextrose is similar to giving a fair amount of free water?
5%
What effect does hypertonic saline have on CO?
On TPR?
- Rapid increase in CO
- Decrease in TPR
What are 5 advantages of hypertonic saline?
- Small volume
- Easy to carry around
- Hypertonicity makes it unlikely to be support bacterial growth
- Inexpensive
- Requires no special management
What is a local effect of hypertonic saline?
Draws fluid from 3rd space and intracellular environment.
What is a central effect of hypertonic saline?
Stimulates a CNS response favoring CV stability.
What are 2 possible types of adverse reactions to fluids that can be seen in the horse?
- Hemolysis
- Cardiovascular alterations
What are 2 possible cardiovascular alterations that can be caused by fluid therapy?
- Arrhythmias
- Ventricular premature contractions
What are 3 possible contraindications for fluid therapy?
- Uncontrolled hemorrhage
- Severe hypernatremia
- Severe hypokalemia
What is a possible complication of fluid therapy?
When is this especially problematic?
- Hypokalemia
- Dilution is especially problematic if decreased intake.
How should bicarbonate be administered when correcting a deficit?
1/2 calculated dose over 1 hour then re-evaluate if more is needed.
Typically in horses with a bicarbonate level greater than or equal to 17-18, what type of fluid should be given?
LRS
What is the maximum rate at which potassium can be administered?
0.5 mEq/kg/hr
What is the common general recommendation for potassium supplementation in horses?
10-20 mEq/L
What is a good rule of thumb for administering potassium in horses?
Not put in the bags an amount greater than the maximum in view of the fastest rate on the administration set-up.
Even though there may be a total body deficit of K+ and Ca++, what might be normal?
Plasma levels of K+ and Ca++ may be within normal levels.
Always supplement fluid with what electrolyte, especially if there is decreased intake?
K+
What electrolyte can be added to fluids, though more conservatively?
Ca++
What electrolyte should not be added to deficit replacement fluids?
Why?
- K+
- Deficit replacement fluids are running very fast, chance of going over K-max.
When giving fluids, never hang more than how much K+?
Max dose for one hour.
Horses typically have one type of losses as it relates to GIT disease?
Isotonic losses
If a horse experiences chronic diarrhea and is only provided with water to drink, what can happen to electrolyte levels?
Electrolytes will be diluted.
What are 3 possible complications associated with restoring normal sodium concentrations?
- Acute or chronic alterations
- Hypo or hypernatremia
- Development of altered CNS osmolarity
Slowly, progressively decreasing sodium can result in what?
Results in compensatory decrease in neuronal intracellular tonicity.
If there is no difference between tonicity within and outside the cell, what happens to the fluid?
No fluid shift occurs, so no dysfunction occurs.
Acute fluid administration with chronic hyponatremia can lead to what?
Cell shrinkage and neurological dysfunction.
What happens to cells with acute hypernatremia?
Chronic compensation?
Chronic past the point of compensation?
- Acute: Cell shrinkage
- Chronic with compensation: Cell swelling
- Chronic past compensation: Cell shrinkage
What happens to cells with acute hyponatremia?
Chronic compensation?
Chronic past the point of compensation?
- Acute: Cell swelling
- Chronic with compensation: Cell shrinkage
- Chronic past compensation: Cell swelling
What are 3 anticipated alterations seen with esophageal obstruction?
- Hypochloremia
- Hyponatremia
- Metabolic alkalosis
What are 3 patterns of electrolyte disturbance seen with endurance racing horses?
- Hypocalcemia and hypokalemia
- Metabolic alkalosis
- Synchronous Diaphragmatic Flutter (SDF)
Is synchronous diaphragmatic flutter a disease?
No
The presence of synchronous diaphragmatic flutter is an indication of what?
Underlying electrolyte acid/base imbalance.
What is the main electrolyte disturbance seen with synchronous diaphragmatic flutter?
What 2 other disturbances are seen?
- Hypocalcemia
- Hypokalemia and metabolic alkalosis
With synchronous diaphragmatic flutter, there is hyperexcitability of what nerve?
There is contraction of this nerve with what?
- Phrenic nerve
- With each atrial contraction.
What does synchronous diaphragmatic flutter look like clinically?
What is the respiration rate equal to?
- Hiccups
- Respiration rate is equal to heart rate
What are 2 anticipated alterations seen with intestinal accidents?
- Hypovolemia
- Metabolic acidosis
What are 5 anticipated alterations seen with diarrhea dependent on cause and duration?
- Substantial sodium and potassium deficits
- Hyponatremia
- Hypochloremia
- Hypokalemia
- Metabolic acidosis
What are 2 anticipated alterations seen with peritonitis/pleuritis?
- Volume and electrolytes WNL
- Large protein losses
What are 3 independent variables of Stewart’s acid/base?
- Strong ion difference
- P CO2
- Total weak acid concentration
What are 2 possible free water effects?
- Dilutional acidosis
- Concentrational alkalosis
With dilutional acidosis, an increase in water leads to an increase in what?
Acid load
With concentrational alkalosis, a decrease in water leads to a decrease in what?
Acid load
Free water and proteins act similarly because they are both what?
Weak acids