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fluid & elect
fluid and electrolytes
Question | Answer |
---|---|
Why would an obese person be at increased risk for fluid volume deficit? | fat cells have less water in them, there fore a obese person already has less total body water to lean tissue ratio. |
Why are the elderly at increased risk for fluid volume deficit/excess? | they have a lower total body water %, decreased thirst sensation, decreased kidney function |
Why are infants and sm children at greater risk for fluid volume deficit? | they have a greater total body water %, but they loose and replace a large amount of this water daily. |
Fluid found inside the cell is ? | intracellular |
Fluid found outside the cell is ? | extracellular |
fluid that surrounds the cells is called? | interstitial or tissue fluid |
fluid also know as plasma is? | interstitial and intravascular |
where is transcellular fluid found? | CSF, GI, Plural space, synovial, intraoccular |
Solutes are? | particles that can be dissolved in a fluid |
Solvent is? | a liquid that can dissolve a solute |
What is simple diffusion? | diffusion that requires no energy to cross a permeable membrane |
What is facilitated diffusion? | diffusion that requires a carrier molecule to move a substance across a membrane (eg. glucose needs insulin to cross) |
Describe how diffusion moves molecules across a membrane. | molecules move from areas of higher concentration of water to areas of lower concentration of water and stop when they are equal on both sides. |
What is osmosis? | the movement of H2O between two compartments from areas of low solute concentration to areas of high solute concentration, until they are equal |
What is osmotic pressure? | the amount of pressure needed to stop the osmotic flow of water. |
the movement of MOLECULES from areas of high concentration to areas of low concentration is? | diffusion |
the movement of WATER from areas of low solute concentration to areas of high solute concentration is? | Osmosis |
What is the tonicity of Isotonic Solution? | it has equal parts solvent/solute |
What is the tonicity of Hypotonic Solution? | more water than particles |
What is the tonicity of Hypertonic Solution? | more particles than water |
What type of fluid shift does Isotonic solution cause? | none |
What type of fluid shift does Hypotonic solution cause? | fluid exits vessels and enters cells |
What type of fluid shift does Hypertonic solution cause? | fluid exits the cells and enters the vessels |
What is Osmolarity? | total solute concentration in each unit of a solution (blood/urine) |
What does Osmolarity measure? | the concentration of blood and urine |
What is the normal value for osmolality? | 275-295mOsm/kg |
What does a high plasma Osmolality indicate? | water deficit (hypertonic) |
What does a low plasma osmolality indicate? | water excess (hypotonic) |
What effects dose high osmolality have on fluid shift? | water is pulled form the cells into the vessels |
What clinical symptoms are seen with high osmolality? | altered neurological symptoms because the cells shrink and die |
What effects does low osmolality have on fluid shift? | water is pulled from the vessels into the cells |
What clinical symptoms are seen with low osmolality? | also causes altered neurological symptoms because cells swell and burst |
What can cause low olmolality? | gaining or retention of water |
oamolality indicates how well you body is? | balancing water |
What is the formula for estimating serum osmolality? | sodium X 2, then glucose divided by 8, then add the two together |
what is hydrostatic pressure? | Pressure/force in the capillaries that pushes(arterial end) or pulls (venous end) fluid in or out |
What causes Hydrostatic Pressure? | Heart beat and blood pressure |
What does hydrostatic pressure at the arterial end do? | pushes fluid out of the capillaries and into the tissues |
what does hydrostatic pressure at the venous end do? | pulls fluid back into the capillaries from the tissues |
what is oncotic pressure? | the pressure created by colloids in the vessels that pulls water from the tissues back into the vessels |
What is the nickname for oncotic (colloidal) osmotic pressure? | water magnet |
In the vascular system colloidal osmotic pressure is created by? | protein molecules (albumin) |
How does albumin(protein) create colloidal osmotic pressure)? | protein is a lg. molecule,that can't cross the vessel wall. it attracts water and holds it inside the blood vessel. |
how does oncotic osmotic pressure effect increased hydrostatic pressure? | the colloidal osmotic pressure is always working to draw in fluid from the tissues,the increased hydrostatic pressure causes edema, but the osmotic pressure reduces some of the edema. |
What happens with increased venous capillary hydrostatic pressure? | the pressure in the venous end of the capillary it to great and the fluid in the tissues cannot reenter the capillary. |
increased venous capillary hydrostatic pressure causes? | edema |
What causes increased venous capillary hydrostatic pressure? | fluid overload, heart failure, faulty valves in the legs |
What happens during decreased plasma oncotic pressure? | there is not enough osmotic pressure in the vessels to draw fluid back in. |
decreased plasma oncotic pressure causes? | edema |
What could cause a decrease in plasma oncotic pressure? | low protein |
What happens during an increase in interstitial oncotic pressure? | something damages teh capillary wall and protein escapes into the tissues, this causes a higher solute concentration in the tissues and water is drawn in. |
incresed interstitial oncotic pressure causes? | edema |
what could cause an increase in interstitial oncotic pressure? | trauma, inflammation |
increase in plasma osmotic or oncotic pressure causes? | fluid to be drawn into the vessels (plasma) |
What things can cause a increase in plasma osmotic or oncotic pressure? | administration of colloids, hypertonic fluids |
increase in tissue hydrostatic pressure causes? | fluid in the tissues will shift into the vessels (plasma) |
What is first spacing? | normal fluid distribution between ICF and ECF |
What is second spacing? | when fluid accumulates in interstitial areas (edema) |
What is third spacing? | When fluid accumulates in an area where exchange cannot take place. |
What things cause third spacing? | ascites, plural effusion, pericardial effusion, burns, heart failure,stress malnutrition. |
What is ascites? | abnormal collection of serous fluid in the abdominal cavity |
What is the body's primary protection mechanism against hyperosmolaity or fluid volume deficit? | thirst sensation |
How does the thirst sensation help regulate water balance? | when osmolaity rises and solutes are becoming concentrated, the thirst sensation causes person to drink water. |
How is water regulated in the body by the renin-angiotensin-aldosterone system? | decreased blood volume and renal perfusion activate the system, and result in the secretion of aldosterone which causes Na+ and water retention |
What is urine osmolality? | another test of fluid balance and kidney filtering ability, that measures solute concentration of the urine |
an increase in urine osmolality indicates? | fluid deficit |
an decrease in urine osmolality indicates? | fluid excess |
What is Urine Specific Gravity? | a test that measures the density of urine,and is effected by the amount and weight of solutes in the urine |
What is normal lab value for urine specific gravity in an adult? | 1.005-1.030 |
What is the normal lab value for urine specific gravity in infants? | 1.001-1.020 |
The higher the value of urine specific gravity means? | the more solutes and the more concentrated the urine, indicating dehydration |
The lower the value of urine specific gravity means? | the less solutes and the more diluted the urine is, indication over hydration |
IV solutions are know as? | crystalloids |
What IV solutions are isotonic? | D5W, 0.9%NaCl(normal saline), lactated ringers |
What IV solutions are hypotonic? | D5W, 0.45% NaCl |
What IV solutions are hypertonic? | D10W, 3-5% NaCl,D5NS, D50.45%NaCl,D5LR |
Why is D5W isotonic and hypotonic? | the D5W is isotonic when it is first infused, but because the dextrose is rapidly used by the body it quickly becomes hypotonic. |
Which IV fluid would you use to replace water losses and treat hypernatermia? | D5W or D5NS |
Which IV fluid is commonly given to surgical patients? | Lactated Ringers |
What is the only IV fluid that can be given with blood products? | 0.9%NaCl (normal saline) |
What special instructions are to be followed if giving 3.0%NS? | Must be given slowly with extreme caution b/c can trigger dangerous intravascular volume overload and pulmonary edema |
What IV solutions are most similar to the composition of plasma? | ringers solution & lactated ringers solution |
Colloids are know as? | plasma expanders---fluid magnets |
If your patient is receiving colloids it is important to? | watch closely during infusion for signs of hypervolemia (fluid overload) |
Signs and symptoms of fluid overload include? | crackles and edema |
What exactly does a colloid do? | stay in the vascular space and this increases osmotic pressure, causing fluid to move from the tissues into the vessels, increasing plasma volume. |
What are the types of colloids given to patients? | serum albumin 5%, Serum albumin 25% (both natural albumin taken from donated blood), dextran & hetastarch(hespan) which are man made |
Serum albumin 5% is? | osmotically equal to blood |
Serum albumin 25% is? | more concentrated than blood and pulls fluid equal to 4X is volume into circulation. |
When would you use serum albumin 25%? | severe malnutrition, sever burns, decreased protein production in the liver. |
What is the best indicator of fluid balance? | daily weight |
1kg of weight is equal to? | 1 liter of fluid |
What labs are important to watch for fluid balance? | H&H, BUN, creatin, Na+, urine specific gravity, serum and urine osmolaity, total protein, albumin |
General Assessment for fluid balances should include? | health HX, daily weight, I/O, V/S, skin turgor, Mucous Membranes,hand vein filling, labs |
What are the causes of Fluid volume deficit? | abnormal losses, poor intake, plasma to interstitial shifts, high fever, heatstroke(increase insensible loss), hemorrhage, GI losses (vomitin, NG suction, diarrhea, fistula drainage), overuse of diuretics, 3rd space fluid shifts. |
What is the goal of treatment with fluid volume deficit? | treat cause and replace water and needed electrolytes |
What are the symptoms of Fluid volume deficit? | dry skin, poor turgor, decreased cerebral perfusion(restlessness, lethargy,confusion), increased pulse, vasoconstriction, increased RR, weight loss, decreased urine output |
What IV solution is used to treat FVD? | LR if a bolus (rapid replacement) is needed. Blood if deficit is caused from blood loss. |
What labs would you most expect to see an increase in with FVD? | Hematocrit &hemoglobin (b/c hemoconcentration) |
What other labs are increased because of FVD? | effected electrolyte, urine specific gravity, osmolality, BUN. |
What lab is decreased as a result of FVD? | CVP (central venous pressure) is decreased b/c less fluid entering the r-atrium |
What can cause FVE? | excessive intake, abnormal retention, interstitial to plasma shift, heart failure, renal failure, long term use of cortiocosteroids |
What is the goal of treatment for FVE? | treat the cause, remove excess fluid while protecting electrolyte balance |
What are the symptoms of FVE? | headache, confusion, lethargy, bounding increased pulse, increased BP, distended neck veins, dyspnea, crackles, pulmonary edema, weight gain, peripheral edema |
What is Anasarca? | a great amount of generalized edema over entire body |
Edematous skin needs? | to be protected from injury it is fragile |
If a patient is bedfast where do you check for edema? | the sacrum |
What labs are associated with FVE? | electrolytes, H&H, urine specific gravity, urine osmolaity, serum osmolarity, |
Will labs be increased or decreased with FVD? | all decreased except CVP will be increased |
What is the care for FVD? | treat underlying cause, oral or IV fluids, monitor for fluid overload, daily weight, I/O, V/S, mental status, turgor, hand vein filling, orthostatic hypotension,skin & oral care, s/s of altered tissue perfusion, safety prec.& labs |
To prevent orthostatic hypotension you should? | make sure the pt has no sudden position changes |
Patient teaching for FVD should include? | preventative measures for orthostatic hypotension |
Symptoms of altered tissue perfusion are? | restleness, anxiety, aggitation, decreased muscle strength, decreased urine output, orthostatic hypotension |
Pt with FVD skin is thin and dry you should? | provide skin care but avoid using harsh soaps, use lotion and mild soap. |
Care for pt with FVE includes? | treating underlying cause, fluid restriction, diuretic, sodium restriction, daily weight, I/O, assess V/S, mental status,skin turgor, hand and neck vein engorgement, position for resp. comfort, skin & oral care, labs |
If patient is on fluid restriction they usually are allowed to have? | 1500mL/day |
Patient teaching for FVE should include? | fluid restrictions, medications, how to do I/O, ways to decrease edema |
Which group of people are more likely to suffer from fluid deficit? | pediatric and elderly |
Why are infants more likely to suffer from fluid deficit? | cant tell you they are thirsty or symptoms, have lgr. body surface area, higher BMR causes greater heat production & more insensible fluid loss, immature kidney function--cant concentrate urine |
Why are the elderly more likely to suffer from fluid deficit? | reduced thirst sensation, decreased kidney function--reduced ability to concentrate urine, decreased reserve of body fluids. |
dry mouth, and poor skin turgor in the elderly? | is not a reliable sign of FVD. |
what S/S do children with dehydration have? | incresed P & BP, irritable/ lethargic, decreased tears, dry;cold skin, sunken anterior fontanel, cap refill >5sec (over2),sunken eyes,rapid respriations |
Whats the formula for calculation of pediatric IV rate? | weight in kg...1st 10kg X 100.....2nd 10kg or up to 10 X 50.....any remainig X 20....add all numbers and divide by 24. |
How is acute diarrhea and dehydration treated? | 1st with oral replacement therapy (pedialyte) 1st dose..40-50mL/kg in 4hrs, Maintenance ORT..alternate ORT with other fluids, regular diet for older children, every time pass a stool replace 1:1 (4-8oz per stool if vol. ukn). |
If the dehydrated/diarrhea child is vomiting? | still give ORT every 1-5min |
the key in ORT is? | to keep something down (may be 5-10mL q5min) |
What type of diet should a child with dehydration/diarrhea have? | continued feeding or early reintroduction of normal diet, breastfeeding should continue with ORT supplments |
What do you teach the parents about home treatment for dehydration/diarrhea? | avoid caffeine, chicken/beef broth, watch for dehydration,to give ORT initially 40-50ml/kg over 4hrs, then q1-5min even if vomiting (may need to give 5-10mL in syringe q5min), allow child to eat normal diet if tolerated. |
Normal potassium levels are? | 3.5-5.0 |
Potassium plays a vital role in? | nerve impulse transmission and muscle contraction. |
Dose the body store potassium? | no, must intake 40-60mEq a day |
Potassium is absorbed in the? | GI tract |
Potassium is regulated by? | kidneys & aldosterone |
How does trauma effect potassium? | cause potassium to be released from the cell,and enter the tissues, will cause edema |
What is the relationship between Na+ and K+? | there is a constant influx between the two..when one goes out the other goes in.to keep the balance..so increased Na+ causes decreased K+..decreased K+ causes increased Na+ |
If the kidneys are not function right then K+ | doesnt get stored and you have a decrease in K+ |
K+ is primarily regulated by? | the kidneys and aldosterone |
Because K+ plays a critical role in nerve impulses transmission and muscle contraction increases/decreases greatly effect? | neuromuscular and heart function |
What value represents hypokalemia? | < 3.5 |
Major causes of hypokalemia are? | GI loss:diarrhea, NG suction, laxative abuse, vomiting, ileostomy drainage, renal losses:diuretics, elevated aldosterone, failure to include K+ in IV fluids when NPO or prolonged NPO status. |
The most serious problem associated with hypokalemia will be? | cardiac problems |
How does hypokalemia cause cardiac problems? | decreased K+ causes reduced excitability of cells, the heart is unable to re-polarize. |
How does hypokalemia look on a ECG? | ST depression, flat T-wave, and appearance of U-wave |
Metabolic alkalosis can cause? | hypokalemia (hydrogen ions needed to make acid, cell send out H ions and K+ goes in to replace them) |
Insulin administration can also cause? | hypokalemia |
Clinical Manifestations of hypokalemia are? | fatigue, N/V, weak irregular pulse, muscle weakness, decreased GI motility/paralytic ileus, paresthesias, decreased reflexes, flat T-waves, possible U-waves. |
How does Hypokalemia and Digitalis effect one another? | hypokalemia increases the chance for digitalis toxicity...Check digitalis levels!! |