Hydration
-Level of fluid in the body
Animals take in water by:
-Eating moist foods and drinking fluids-Metabolic water
Animal lose water
-Insensible-Sweating, vocalizing, urinating, defecating-Vomiting, diarrhea, excessive sweating, hemorrhaging, and elevated body temperature
Insensible Water Loss
-Diffused passively away from the skin-Vaporized during respiration
Intracellular
-Inside cell-2/3 of total body water
Extracellular
-Outside cell-1/3 of total body water
Interstitial
-Between cells-3/4 of extracellular
Intravascular
-In vessels-1/4 of extracellular
Highest Intracellular Concentration
-Potassium-Magnesium-Hydrogen phosphate-Sulfate
Highest Extracellular Concentration
-Sodium-Bicarbonate-Chloride
Osmolality
-Measurement of solute concentration in fluid
Isotonic
-Osmolality comparable to that of blood
Fluid outside cell has:
-Same concentration of dissolved substances as in the cytoplasm.
Hypotonic
-Osmolality is less than that of blood-Fluid outside the cell has lower concentration of solutes then in the cytoplasm-water flows into the cell and cause it to swell and possibly to break
Hypertonic
-Osmolality is greater than that of blood-Fluid outside of cell is more concentrated than in the cytoplasm-Water shifts into the extracellular space, causing the cell to shrink and become shriveled
Edema
-Abnormal/excess accumulation of fluid in tissue-Ex. Pulmonary and Cutaneous
Pulmonary Edema
-Excess fluid in lung tissue
Subcutaneous Edema
-Fluid under the skin
Crystalloid
-Composed of water rich with electrolytes-Solutes are small
Colloid
-Heavy molecules suspended in isotonic crystalloid-Solutes too large to cross vascular wall
Fluid Therapy phases
-Resuscitation-Replacement-Maintenance
Resuscitation
-Increase intravascular volume (BP)
Replacement
-Correct dehydration
-Maintenance
-To mitigate decreased H2O intake and/or ongoing loses
Passive process
-Do not require energy
Active processes
-Do require energy
Diffusion
-Kinetic movement of molecules from higher to lower concentration
Facilitated Diffusion
-Selective carrier proteins assist in movement of molecules from higher to lower concentration
Osmosis
-Passive movement of water through a semipermeable membrane from dilute solution to a more concentrate one
Osmotic Pressure
-Force that affects water movement from one side to the other
Oncotic Pressure
-The Contribution of blood colloids to osmotic pressure (albumin in particular)
Ascites
-Fluid leaks into abdominal space
Filtration
-Dependent on pressure gradient and membrane permeability
Hydrostatic pressure
-Force that pushes liquid