IV Fluids

"5 R's" of IV fluid therapy

Resuscitation

Routine maintenance

Replacement

Redistribution

Reassessment

Tonicity

The ability of a solution surrounding a cell to cause that cell to gain or lose water

osmosis

Diffusion of water through a selectively permeable membrane

diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

colloid solutions

Solutions that contain large molecules (proteins)- will not pass through semipermeable membrane

colloid solution characteristcs

very expensive; long lasting; reactive tonicity

Colloid solutions contain

Albumin (5-25%)

Dextran

Blood products (whole blood, packed RBC, plasma)

Crystalloid solutions

Solutions of small molecules (salts/ sugars) in water- pass through semipermeable membrane

crystalloid solution characterisitcs

cheaper and come in different tonicities

isotonic solutions

Solutions do NOT promote fluid shifts- for fluid deficits/replaces ECF losses (hypovolemia)

Isotonic IV solutions

equal concentration to blood: normal saline and lactated ringers

Normal saline

0.9% NaCl - used n conjunction with blood products

Lactated Ringers

contains electrolytes (Na+, K+, Cl, Ca++)- for trauma, burns, dehydration

Hypotonic solutions

causes fluid shift INTO the cell (swelling); used for intracellular dehydration

Hypotonic IV solutions

less concentration than blood: 0.45% saline and D5W

D5W

5% dextrose in water; causes shift from Isotonic → hypotonic bc of sugar metabolism

Hypertonic Solutions

Solutions cause fluid to shift OUT of the cell (shrink); administer with caution to treat cerebral edema and hyponatremia

Hypertonic IV

higher concentration than blood: > 0.9% saline (3% or 5% NaCl)

Total Parenteral Nutrition (TPN)

nutrient-complete solution given directly into bloodstream via central line; 3-6x osmolarity normal plasma

TPN contains

Dextrose, amino acids (PROTEIN), fat emulsion, trace minerals, multivitamin & electrolytes

Peripheral Parenteral Nutrition (PPN)

moderate nutrient supplementation through a peripheral vein via a catheter