Fluid Therapy Flashcards
What % of an animal’s body consists of water?
60-70%.
What portion of total body water (TBW) is intracellular?
2/3.
What portion of total body water (TBW) is extracellular?
1/3 (4% in the blood or lymph vessels and 16% interstitial fluid).
How is interstitial fluid created?
By ultrafiltration.
What is ultrafiltration?
Where pressure in the capillaries forces small molecules out of the capillaries, while large molecules stay inside the capillaries.
What is interstitial fluid similar to?
Plasma, w/o proteins or RBCs.
What is the purpose of extracellular fluid?
To bathe cells, supply oxygen to the cells, and provide nutrients to the cells.
What is edema?
Abnormal excess accumulation of fluid in tissue.
What is pulmonary edema?
Abnormal excess accumulation of fluid in the lungs.
What is cutaneous/pitting cutaneous edema?
Abnormal excess accumulation of fluid under the skin that has little pits in it when pushed on.
What is edema a common sign of?
The abnormal movement of fluid from the vascular to interstitial space.
What is diffusion?
The movement of molecules from high concentration to low concentration along a concentration gradient until equilibrium is reached.
ex: Opposite of osmosis.
What 3 factors determine the ability of a molecule to pass through the cell membrane?
- Molecular charge (Charged molecules require a special pore/channel to pass through a cell membrane).
- Molecular size (The larger the molecule, the more difficult it is for it to pass through the cell membrane).
- Lipid solubility (Lipid soluble molecules will more easily pass through the cell membrane).
What is osmosis?
The PASSIVE movement of water through a semipermeable membrane from a dilute solution to a more concentrated one (Higher solvent to lower solvent or Lower solute to higher solute) until equilibrium is achieved.
*Opposite of diffusion.
What is osmotic pressure?
The force of water moving from one side to the other.
What are the characteristics of isotonic fluid?
- Osmolality comparable to that of normal blood.
- ECF has the same concentration of dissolved substances as intracellular fluid.
What are the characteristics of hypotonic fluid?
- Osmolality is less than that of normal blood.
- Cytoplasm of the cell is more concentrated than the ECF.
- Water flows into the cell and causes it swell and possibly lyse.
ex: 0.45% NaCl.
What are the characteristics of hypertonic fluid?
- Osmolality is greater than that of blood.
- ECF is more concentrated than the cytoplasm.
- Water shifts into the extracellular space, causing the cell to shrink and become shriveled. Could possibly crenate.
ex: Hypertonic saline (7% NaCl).
How many mL of water is lost in urine daily?
20 mL/kg.
How many mL of water is lost in feces daily?
10-20 mL/kg.
How many mL of water is lost in expired air daily?
20 mL/kg.
What is the maintenance fluid rate for all animals?
50-60 mL/kg/day.
Is water static or dynamic?
Dynamic, it is constantly shifting location and being replaced or lost.
What are 5 ways water is lost?
- Respiratory.
- Urine.
- Panting.
- Feces.
- Tears.
What are the 2 ways water is replaced?
- Water in food.
- Drinking.
Why is fluid loss greater in sick/injured animals?
Due to blood loss, diarrhea, and vomiting.
What can water loss as a result of being sick lead to?
Dehydration and shock.
What are the reasons for fluid therapy?
- Maintain hydration (animal is not eating).
- Correct dehydration.
- Replace ongoing fluid loss. (Ongoing vomiting and diarrhea).
- Maintain IV access and deliver other medications (CRI of nausea meds or pain meds).
- Treatment of shock or hypoproteinemia.
- Increase urine output.
- Correct acid-base or electrolyte abnormalities.
- Provide nutritional support.
What are the 3 types of fluid that could be given during fluid therapy?
- Crystalloids.
- Blood products.
- Colloids.
What are the characteristics of crystalloids?
- Contains electrolytes and water.
- Includes hypotonic, isotonic, and hypertonic solutions.
What are the characteristics of 5% Dextrose (D5W)?
- Hypotonic crystalloid.
- Provides free water.
- Cannot be given rapidly.
- Used for treating hypernatremia.
What are the characteristics of 0.9% NaCl (LRS)?
- Isotonic crystalloid.
- Commonly used for replacement, rehydration, and resuscitation.
What are the characteristics of 7% hypertonic NaCl?
- Hypertonic crystalloid.
- Provides electrolytes greater than water.
- Causes a shift of interstitial water into the intravascular space, leading to volume expansion.
- Used for resuscitation.
What are the characteristics of colloids?
- High molecular weight, so stays in IV space longer.
- Natural and synthetic forms.
- Used for resuscitation and to provide oncotic support.
What are the 2 natural colloids?
- Albumin.
- Plasma.
What are the 2 synthetic colloids?
- Dextran.
- Hetastarch.
What are the 3 phases of fluid therapy?
- Resuscitation phase.
- Replacement phase.
- Maintenance phase.
What is the goal of the resuscitation phase?
Restoring vascular volume to reverse hypovolemia and/or shock.
What is the shock dose of isotonic fluid in dogs and horses?
80-90 mL/kg.
What is the shock dose of isotonic fluid in cats?
40-60 mL/kg.
What is Dr. Knight’s method of giving a shock dose of isotonic fluids?
Give 1/4 of the dose, then reassess.
What is the equation used to determine the amount of fluids needed during the replacement phase?
Dehydration + Ongoing losses* + Maintenance.
*Measured or Estimated.
What is the equation used to calculate dehydration?
(Estimated % dehydration) X (BW in kgs) =Amount of dehydration in L.
*Given during a 24 hour period.
What are the 6 ways to assesses hydration status?
- Check the feel of the mucous membranes.
- Skin turgor/tenting.
- Serial body weights.
- Sinkage of eyes.
- CRT.
- Laboratory data (PCV, TP, USG).
What is the equation used to calculate the amount of fluids given during surgery?
10 ml/kg/hour.
What are the 5 routes of fluid administration?
- Intraosseous (Done in reptiles).
- Oral.
- Intraperitoneal.
- SQ.
- IV.
What are the two types of infusion sets?
- Macro infusion sets.
- Micro infusion sets.
What are the characteristics of the macro infusion set?
- Larger drop size.
- Used for large animals.
- 10-15 GTT/mL.
What are the characteristics of micro infusion sets?
- Smaller drop size.
- Used for smaller patients.
- 60 GTT/mL.
What 2 things can be used by fluid administration sets to administer fluids?
- An infusion pump.
- Gravity flow.
How is drip rate calculated?
Fluid rate (mL/hour) X (1 hour/3600 seconds) X (GTT/mL) = GTT/second.
What are the 7 signs of fluid overload?
- Increased CVP/blood pressure.
- Hyperpnea.
- Pulmonary edema.
- Chemosis (edema of the ocular conjunctiva).
- Restlessness.
- Cutaneous/pitting edema.
- Serous/watery nasal discharge.
