fluid and electrolyte Flashcards
active transport
metabolic energy is expended, movement from less concentrated solution to more concentrated one.
anion
Negatively charged ion
body surface area
is proportionately greater than that of adults, increasing insensible fluid losses. the greater the BSA, the greater the risk when burned. new born 75% total body water ECF 45% ICF 30% infant 65% total body water ECF 25% ICF 30-40% child/adolescent 50% total body water ECF 10-15% ICF 40%
cation
positively charged ion
colloid
substances such as large protein molecules that do not readily dissolve into true solutions.
colloid osmotic pressure/oncotic pressure
pulling water from the interstitial space into the vascular compartment. important mechanism in maintaining vascular volume.
crystalloid
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
passive movement of electrolytes or other particles down the concentration gradient (from higher to lower concentration)
edema
occur when the body has excess fluid. swelling caused by excess fluid trapped in body tissues.
electrolyte
charged ions capable of conducting electricity , in various concentrations and combinations.
extracellular fluid (ECF)
found outside the cells and accounts for about 1/3 of total body fluid
filtration
movement across a membrane, under pressure from a higher to lower pressure
fluid volume deficit
output substantially exceeds intake
fluid volume excess
intake substantially exceeds output
hematocrit
measures the volume (percentage) of whole blood that is composed of RBC’s. is a measure of the volume of cells in relation to plasma, it is affected by changes in pasta volume. hematocrit increases with severe dehydration and decreases with severe over- hydration.
hydrostatic pressure
the major force that pushes water out of the vascular system at the capillary level and into interstitial fluid
hyperkalemia
elevated potassium levels, ultimately corrected by dialysis, but treatments such as administration of glucose and insulin can help to drive potassium back into the cell where elevated levels will crate less risk.
hypernatremia
sodium excess/reduced production of antidiuretic hormone (ADH)/ corrected by admin of ADH
hypertonic
solutions have a higher osmolality than body fluids: 3% sodium chloride is a hypertonic solution
hypodermoclysis
fluid admin subcutaneously/when fluid by IV is problematic/especially OA
hypokalemia
deficit in potassium / side effects of diuretics.
hyponatremia
deficit in sodium/ treated with oral supplementation or IV supplementation may be admin.
hypotonic
solutions such as one-half normal saline (0.45% sodium chloride) lower osmolality than body fluids.
insensible fluid loss
occurs through the skin and lungs. not noticeable and cannot be measured
skin- 2 ways/water lost through diffusion and perspiration (lost noticeable not measurable)
diffusion water loss 300-400 mL per /day. can be increased in the protective layer of skin is lost.
perspiration varies on factors; environmental temp, and metabolic activity.
fever and exercise increase metabolic activity and heat production, increasing fluid losses through skin.
interstitial fluid
surrounds the cells, 75% of the ECF
intracellular fluid (ICF)
found within the cells of the body
intravascular fluid
plasma,, accounts for approx 20% of the ECF
ions
charged particles
isotonic
has the same osmolality as body fluids
milliequivalent
refers to the chemical combining power of the ion, or the capacity of cations to combine with anions to form molecules. combining activity is measured in relation to combining activity of the hydrogen ion (H+)
1 mEq of any anion equals 1 mEq of any cation.
obligatory losses
fluid losses are required to maintain normal body function. adult excrete 500mL through kidneys each day to eliminate metabolic waste products from the body.
oncotic pressure
pulling water from the interstitial space into the vascular compartment. important mechanism in maintaining vascular volume. AKA- colloid osmotic pressure
osmolality
concentration os solutes in body fluids. determined by the total solute concentration within a fluid compartment and is measured as parts of south per kilogram of water.
reported as milliosmols per kilogram (mOsm-/kg) sodium being the greatest with glucose and urea also contribution.
potassium, glucose and urea primary contributors ICF
osmosis
movement of water from an area of lesser to one of greater concentration through a semi-permeable membrane
osmotic pressure
the power of a solution to draw water across a semipermeable membrane.
an inward-pulling force caused by particles in the interstitial and intracellular fluids
saline
normal saline, o.9% sodium chloride, isotonic solution.
solvent
component of a solution that can dissolve a solute. ex: sugar added to coffee
tonicity
used to refer to the osmolality of a solution.
transcellular fluid
component of ECF; cerebrospinal, pericardial, pancreatic, pleural, intraocular, biliary, peritoneal,, and synovial fluids.
ADH
regulates water excretion from the kidney, synthesized in the anterior portion of the hypothalamus and acts on the collecting ducts of the nephrons. serum osmolality rises, ADH is produced.
renin-angiotensin-aldosterone system
specialized receptors in the juxtaglomerular cells of the kidney nephrons respond to changes in renal perfusion which initiates the RAAS.
