Fluids and Electrolyte terms

Active transport

process that uses metabolic energy to move substances across cell membranes from a less concentrated solution to a more concentrated one

Anions

ions that carry a negative charge

Body surface area (BSA)

the relationship between height and weight measured in square meters

Cations

ions that carry a positive charge

Colloid osmotic pressure

pulling water from the interstitial space into the vascular compartment; also called oncotic pressure

Colloids

substances such as large protein molecules that do not readily dissolve into true solutions

Crystalloids

salts that dissolve readily into true solutions

Dehydration

a condition that occurs when a body does not take in as much water as it loses or lacks sufficient reserves to maintain proper function

Diffusion

the continual intermingling of molecules in liquids, gases, or solids brought about by the random movement of the molecules

Edema

swelling caused by excess fluid trapped in body tissues

Electrolytes

charged ions capable of conducting electricity

Extracellular fluid (ECF)

fluid found outside the cells; accounts for about one third of total body fluid

Filtration

a process whereby fluid and solutes move together across a membrane from one compartment to another

Fluid volume deficit (FVD)

when output substantially exceeds intake

Fluid volume excess (FVE)

when intake substantially exceeds output

Hematocrit

measures the volume (percentage) of whole blood that is composed of RBCs

Hydrostatic pressure

the pressure a fluid exerts within a closed system on the walls of its container

Hyperkalemia

elevated potassium levels

Hypernatremia

a sodium excess

Hypertonic

solutions having a higher level of solutes such as D5NS or D5LRS

Hypodermoclysis

fluid administered subcutaneously

Hypokalemia

a deficit in potassium

Hyponatremia

a sodium deficiency

Hypotonic

solutions having less solute than isotonic fluids such as 0.45% normal saline

Insensible fluid loss

loss that occurs through the skin and lungs; it usually is not noticeable and cannot be measured

Interstitial fluid

surrounds the cells and accounts for approximately 75% of the ECF

Intracellular fluid (ICF)

fluid found within the cells of the body

Intravascular fluid

(plasma) found within the vascular system and accounts for approximately 20% of the ECF

Ions

charged particles

Isotonic

solution having the same osmolality as body fluids

Milliequivalent

the chemical combining power of the ion, or the capacity of cations to combine with anions to form molecules

Obligatory losses

certain fluid losses required to maintain normal body function

Oncotic pressure

pulling water from the interstitial space into the vascular compartment; also called colloid osmotic pressure

Osmolality

the concentration of solutes in body fluids

Osmosis

the movement of water across cell membranes, from the less concentrated solution to the more concentrated solution

Osmotic pressure

the power of a solution to draw water across a semipermeable membrane

Saline

0.9% sodium chloride, an isotonic solution

Solutes

substances that dissolve in liquid such as oxygen, electrolytes, and glucose

Solvent

the component of a solution that can dissolve a solute

Tonicity

refers to the osmolality of a solution and represents the balance between the amounts of water on either side of a membrane

Transcellular fluid

examples include cerebrospinal, pericardial, pancreatic, pleural, intraocular, biliary, peritoneal, and synovial fluids
A. The body is composed largely of fluids in many forms
1. Blood, serum, saline, albumin, urine, bile, hormones, cerebrospinal
B. Elect