movement of fluid through a cell or blood vessel membrane due to hydrostatic pressure differences on both sides of the membrane
How is blood pressure an example of hydrostatic filtering force?
It moves whole blood from the heart to capillaries where filtration can occur to exchange water, nutrients, and waste products between the blood and tissues
Edema develops when...
increases in venous capillary pressure rise and force fluid into the interstitial tissues
free movement of particles across a permeable membrane from an area of high concentration to low concentration
-movement of water through a semi-permeable membrane
-Water moves from low to high concentration to achieve homeostasis
What is the thirst mechanism?
The feeling of thirst is caused by the activation of cell in the brain that responds to changes in the ECF osmolarity
-fluid left in interstitial tissue following a movement of fluids from the capillary at it's arterial end and back to venous capillary system
-Lymph flow is slower than blood flow
secreted by adrenal cortex when sodium level in ECF in decreased
prevents both water and sodium loss
Antidiuretic hormone (ADH)
stored in posterior pituitary gland
acts on renal tubules in response to changes in blood osmolarity causing water retention
hormones secreted by special cells in the atria (ANP) and ventricles (BNP) of the heart in response to increased blood volume and pressure
***Opposite of aldosterone- increases urine output to reduce circulating blood volume
Fluid intake is less than what is needed to meet the body's fluid needs, resulting in fluid volume deficit
intravascular water shifts out of circulating blood volume into the interstitial (extravascular) space
Physical assessment & clinical manifestations of DEHYDRATION
flattened neck veins in supine position
dry mucous membranes
change in mental status
concentrated urine (increased spec. grav.)
decreased urine output (<500 mL/day cause for concern)
Lab assessment for DEHYDRATION
Hgb, Hct, Serum Osmolality, glucose, protein, BUN, and electrolytes
(All increased because decreased extracellular volume)
excess of body fluid
-most common causes are related to fluid volume excess in the vascular space or to dilution of specific electrolytes and blood components
Assessment of FLUID OVERLOAD
weight gain (EARLIEST INDICATOR)
distended neck veins
(Report >3 lb weight gain/week OR >1-2 lbs in 24 hrs.
Nursing care priority for hyponatremia
monitor pts. response to therapy and prevent hypernatremia and fluid overload
Nursing care for HYPOkalemia
ensures adequate oxygenation, patient safety for falls prevention, prevent injury from potassium administration, monitor pts. response to therapy
Most severe problems from HYPERkalemia
Cardiovascular changes due to ECG changes
Major cause of death in hyperkalemia
(ventricular ectopy, heart block, systole, or ventricular fibrillation)
What does it mean when CALCIUM and PHOSPHORUS are in a balanced reciprocal relationship?
If Calcium increases, Phosphorus decreases
If Calcium decreases, Phosphorus increases
What is a major nursing intervention for HYPERmagnesemia?
Discontinue all oral and parenteral magnesium
Most common reasons for Infusion Therapy
-maintain or correct fluid balance
-maintain or correct electrolyte or acid-base balance
-Replace blood or blood products
Patient's receiving ISOTONIC solutions are at risk for...
-when isotonic infusions are used, water does not move into or out of the body's cells
How do HYPERTONIC infusions work?
move water out of the body's cells (ICF) by osmosis and into the bloodstream (ECF)
LESS WATER, MORE SALT
Complications with HYPERTONIC infusions
vascular overload (increased ECF)
cellular dehydration (decreased ICF)
Complications with HYPOTONIC infusions
causes cells to burst or lyse (increased ICF)
serum (decreased ECF) dehydration
increased serum electrolytes due to hemoconcentration
Vascular Access Device (VAD)
-Where are they used?
-How long can they dwell in a vein?
superficial veins of the hand and forearm
dwell for 72 to 96 hours and then require removal
How do you remove a PICC line?
1-2" at a time, over 1-2 minutes (relaxes, prevents vasospasm, breakage)
MEASURE CATHETER*** make sure you take as much as you gave
Tunneled Central Catheter
portion of catheter lying in a subcutaneous tunnel separates the point at which the catheter enters the vein from where it exits the skin
used for infusion therapy that is frequent and long-term
A subcutaneous pocket is surgically created to house the port body
Port is usually placed in the upper chest or the upper extremity
Port needs to be flushed after each use and at least once a month between courses of therapy
(Most facilities require a heparin-lock flush upon discontinuing infusions
Lumens are very large to accommodate the hemodialysis procedure or a pheresis procedure that harvests specific blood cells
Should not be used for administration of other fluids or medications, except in an emergency
What type of administration set is used when no primary line is present?
Ex: Antibiotic without continuous infusion line
rapid infusion of drugs or bolus infusion that causes shock or cardiac arrest due to introduction of a foreign substance
Used for pressure monitoring, repeated blood gases, & to infuse some chemotherapy agents
slow infusion of isotonic fluids into the subcutaneous tissue, short term fluid replacement
torso preferred site
Administration of opioids and anesthetics for regional pain relief, also steroids and antispasmodics
Ex: Epidural, Subarachnoid injection
Easy access in the proximal tibia or sternum
Used mostly in pediatric population
Now used for trauma, burn, or cardiac arrest victims
Short duration (24 hours), but as effective as peripheral or central IVs for large volume infusions
adrenal gland hormone that causes kidneys to reabsorb sodium into the blood, causing more water to be reabsorbed by osmosis
concentration of solute per kilogram of water, which creates the pulling power of that solution for water
concentration of solute per liter of solution, which creates the pulling power of that solution for water
movement of potassium from the intercellular fluid to the extracellular fluid, leading to elevated serum potassium levels without a true body increase of K+, such as occurs with acidosis
movement of potassium fro the ECF to the ICF, leading to lowered K+ levels without a true decrease of K+ in the body, such as occurs with insulin therapy