Term
| What replacement fluids are currently available? |
|
Definition
1. Crystalloids: Normal saline (0.9%NS, 0.45%NaCl), Lactated Ringers (LR), 5% Dextrose (D5W)
2. Colloids: Albumin 5-25%, hetastarch |
|
|
Term
| What electrolytes are primarily found in the intracellular fluid? |
|
Definition
Potassium (K)
Magnesium (Mg)
Phosphate (PO4) |
|
|
Term
| What electrolytes are found in the extracellular fluid? |
|
Definition
Sodium (Na)
Chloride (Cl)
Bicarbonate (HCO3) |
|
|
Term
| What is a normal electrolyte value? |
|
Definition
Na: 134-146 K: 3.5-5
Cl: 96-100 Mg: 1.4-1.75
BUN: 7-18 (glucose: 70-99)
280-300mOsm/L (Cr: 0.6-1.2) |
|
|
Term
| What is total body water? |
|
Definition
men: 50-60% total body weight
women: 45-55% TBW
**decreases as you age |
|
|
Term
| How much water is found in the intracellular and extracellular fluid? |
|
Definition
2/3 ICF
1/3 EFC (interstitial (lymphatic) and intravascular (plasma)) |
|
|
Term
| What is transcellular fluid? |
|
Definition
| swelling in paracardium, peritoneum, etc (<1% of fluid) |
|
|
Term
|
Definition
measure of the # of asmotically active particles per unit of soln. It independent of the weight or nature of the particle.
Normal osmolarity: 280-300mOsm/L |
|
|
Term
|
Definition
the difference between measured and calculated serum osmolarity. (normal equal/less than 10)
Increases in the presence of ethanol, methanol, ethylene glycol and mannitol |
|
|
Term
| how does water move in respect to osmolarity? |
|
Definition
| low osmolarity to high osmolarity |
|
|
Term
| How does water get into the body? |
|
Definition
Ingested fluids and foods, water byproduct of oxidation.
1400mLs/day of fluid intake |
|
|
Term
| How does water get out of the body? |
|
Definition
| urinary and stool losses, and evaporation of fluids in the lungs and from the skin (insensible losses). |
|
|
Term
| What detects changes in plasma tonicity? (how many osmoles are in there?) |
|
Definition
| Detected by osmoreceptors (in the hypothalamus). it's the thirst center and ADH synthesis |
|
|
Term
| When osmoreceptors detect low osmolarity (too much water vs osmoles in solution) what happens? |
|
Definition
| ADH is inhibited, so water will not be absorbed and dilute urine will be excreted. (<280 osm/kg) |
|
|
Term
| When osmoreceptors detect high osmolarity what happens? |
|
Definition
| ADH is excreted and water is reabsorbed, concentrated urine is excreted. |
|
|
Term
| What are the various body fluid compartments? |
|
Definition
Total Body Water:
2/3 intracellular fluid
1/3 extracellular fluid (interstitial and intravascular) |
|
|
Term
| What happens when you deplete the intravascular fluid? (Bleeding/Trauma) |
|
Definition
| reduces cardiac output and organ hypo-perfusion. |
|
|
Term
| Loss of blood volume, where does the blood get shunted? |
|
Definition
|
|
Term
| What are the signs and symptoms of intravascular volume depletion? |
|
Definition
| tachycardia(>100bpm), hypotension (BP<60), orthostatic changes, increased BUN/SCr ratio, dry mucous membranes, decreased skin turgor, reduced urine output, dizziness, improvement in HR and BP after a 500 or 1000mL fluid bolus |
|
|
Term
| How can you tell if someone has severe depletion of intravascular fluid? |
|
Definition
| improvement in HR and BP after a 500mL or 1000mL fluid bolus |
|
|
Term
| What is the goal in fluid resuscitation? |
|
Definition
| to restore intravascular volume and keep organs perfused. |
|
|
Term
| T/F Depletion of intravascular volume can cause organ dysfunction and death if not corrected in timely manner. |
|
Definition
True. IV fluids should be infused rapidly, administered as 500-1000mL bolus,
crystalloids or colloids (more expensive) used |
|
|
Term
| What can we use for fluid replacement? |
|
Definition
Crystalloids (Water and electrolytes, pass freely through semi-permeable membranes, classified by tonicity.
Colloids (osmotic agents-more expensive, plasma expanders) |
|
|
Term
|
Definition
Isotonic (no shift of fluid)[NS 0.9%]
hypotonic (shift from ECF -> ICF)[half-NS 0.45%]
hypertonic (shift from ICF-> ECF)[hypertonic saline 3%, 7.5%, or 23.4%] |
|
|
Term
| Explain the uses and side effects of Normal saline 0.9%. |
|
Definition
ISOTONIC CRYSTALLOID
used during shock, hemorrhage, burn patients, hypotensive patients, hyponatremia
Adverse effects: hypernatremia, hyperchloremic emtabolic acidosis, fluid overload/dilutional coagulopathy |
|
|
Term
| What do you use lactated ringer's (LR) for? |
|
Definition
ISOTONIC CRYSTALLOID(made to mimic blood)
uses: perioperative setting, lower GI fluid losses, burns/dehydration.
adverse rxns: metabolic alkalosis, hypernatremia, fluid overload |
|
|
Term
| What do you use half normal saline 0.45% for? |
|
Definition
HYPOTONIC CRYSTALLOID
uses: patients hypertonic with primary depletion of ECF
adverse rxns: hypernatremia, hyperchloremic metabolic acidosis |
|
|
Term
| What do you usee Dextrose water (D5W) for? |
|
Definition
HYPOTONIC CRYSTALLOID
uses: severe hypernatremia, dilute IV medications, keeps veins open fo IV medications.
Adverse rxns: hyperglycemia, hypokalemia |
|
|
Term
| What is Hypertonic Saline used for? |
|
Definition
HYPERTONIC CRYSTALLOID
use: traumatic brain injury, severe hyponatremia, due to low serum sodium conc.
Adverse effects: used infrequently due eto shifts in water balance between ECF and ICF, hypernatremia, hyperchloremia |
|
|
Term
| If you have a hypotonic solution, where will water go? |
|
Definition
| ICF will shift out of the cell. |
|
|
Term
| ______ are plasma expanders. |
|
Definition
|
|
Term
| T/F colloids are large oncotically active molecules. |
|
Definition
| True, such as proteins, carbohydrates, and fresh frozen plasma |
|
|
Term
| T/F 25% Albumin is 5x more potent than the intravascular fluid |
|
Definition
| True. Used in hypovolemic states, causes a 5X increase in fluid in the intravascular fluid. So, 100mL 25% albumin causes 500mL to stay in the intravascular system |
|
|
Term
| What is albumin, and when is it used? |
|
Definition
COLLOID
5% albumin is iso-oncotic and used in hypovolemic states
25% albumin is hyper-oncotic and is give with crystalloids to prevent intracellular volume depletion and renal failure. |
|
|
Term
| What are the adverse effects of Albumin? |
|
Definition
| fluid overload, protein overload (your injecting them with protein!), anaphalaxis (IgA deficient patients), and infectious complications [like hepatitis] |
|
|
Term
| What is Hetastarch? side effects? |
|
Definition
| COLLOID similar to 5% albumin, but less expensive. Isotonic. Adverse effects: fluid overload, bleeding, macroamylase formation (looks like pancreatitis in lab values) |
|
|
Term
| What are dextrans? side effects? |
|
Definition
COLLOIDS Polysaccharide plasma expanders
low MW: 40
high MW: 70 & 75
Adverse effects: fluid overload/dilution coagulopathy, anaphylaxis [this is why high MW is not used much], bleeding |
|
|
Term
| What is Fresh Frozen Plasma (FFP) and what are the adverse effects? |
|
Definition
COLLOID used for excessive blood loss, and preventing bleeding due to abnormal coagulation. [used if already infused with crystalloid and if there's a complication]
Adverse rxn: anaphylaxis, viral transmission, increased nosocomial infection rate. |
|
|
Term
| Why would you chose a crystalloid over a colloid? |
|
Definition
|
|
Term
| What electrolytes are found in ICF? |
|
Definition
K, Mg, PO4
Potassium, magnesium, phosphate (low numbers in labs typically) |
|
|
Term
| what electrolytes are found in the ECF? |
|
Definition
Na, Cl, HCO3
Sodium, Chloride, Bicarbonate (typically high numbers (except bicarb) in lab tests, b/c they're outside the cell) |
|
|
Term
| What are the normal values for sodium (Na)? |
|
Definition
serum: 134-146mEq/L
daily requirement: 80-130mEq
resides almost entirely in the ECF
largely determines ECF volume, because water follows Na. |
|
|
Term
|
Definition
low Na in the blood. <134mEq/L
can be:iso- hyper- hypo- tonic (iso-, hypo-, hyper-volemic)
causes: replacement of lost solute with water, volume depletion (vomiting/diarrhea), hypoperfusion or organs (ADH stimulation), diuretics, renal failure |
|
|
Term
| What is the difference between acute and chronic hyponatremia? |
|
Definition
Acute: seizures, coma, respiratory arrest, death (more serious, body hasn't compensated.)
Chronic: lethargy, nausea, HA (less extreme because the body has compensated)
REPLACEMENT IS VERY IMPORTANT |
|
|
Term
| What is isotonic hyponatremia? |
|
Definition
normal serum osmolality (280mOsm) and low Na (<134mEq/L)
(psuedo-hyponatremia) Na shifted into the cells...
caused: hyperlipidemia, hyperproteinemia, isotonic infusion |
|
|
Term
| What is hypertonic hyponatremia? |
|
Definition
elevated serum osmolality (>280mOsm) and low Na(<134mE/L)
caused by hyperglycemia |
|
|
Term
| What is hypovolemic hyponatremia? |
|
Definition
low serum osmolality (<280 mOsm) and low Na (<134mEq/L)
deficit of Na is greater than water deficit
caused by diuretics, profuse sweating, wound drainage, and burns, vomiting/diarrhea, and renal tubular acidosis |
|
|
Term
| What are the signs and symptoms of hypervolemic hyponatremia? |
|
Definition
edema, weight gain, cerebral edema with increase intracranial pressure.
treatment is correction of underlying diseases, Na and water restriction, cautious use of loop diuretics |
|
|
Term
| What are the signs and symptoms of hypovolemic hyponatremia? |
|
Definition
nausea, vomiting, HA, confusion, agitation, disorientation, seizures, coma, respiratory arrest, death
Treatment: Na and water replacement (determine Na deficit) |
|
|
Term
| What is hypervolemic hyponatremia? |
|
Definition
low serum osmolality (<280 mOsm) and low Na (<134 mEq/L)
elevation of fluid volume and elevated Na (it looks low because of the increased volume)
cause: total body Na EXCESS (CHF, liver damage, nephrosis) |
|
|
Term
| What is isovolemic hyponatremia? |
|
Definition
low Na osmolality (<280mOsm) and low Na (<134mEq/L)
Associated with small increases in ECF vol, normal total body Na, imbalance of water intake and excretion
Cause: water intoxication, SIADH (syndrome of inappropriate ADH), renal failure, K loss, medications |
|
|
Term
| What are the causes of SIADH (syndrome of inappropriate ADH) |
|
Definition
| Carcinomas (lung/pancrease), pulmonary (pneumonia, TB), CNS (meningitis, stroke, tumor, trauma), Medications (Sulfa, SSRIs, TCAs, NSAIDs, barbituates, etc) |
|
|
Term
| What is the treatment of isovolemic hyponatremia? |
|
Definition
water/fluid restriction <500mL/day
Na <110mEq/L, hypertonic saline 3% used with diuretics (loops)
SIADH: demeclocycline, phenytoin, and lithium |
|
|
Term
| What are the steps in treating fluid/ion imbalances? |
|
Definition
1. find the cause
2. treat the cause
3. do we need to raise Na? do it SLOWLY
4. look at the fluid status, retaining (restrict fluid) or need fluid(replace fluid, once restored ADH will stop)
5. kalemia is reflective of natremia typically |
|
|
Term
|
Definition
serum Na>146mEq/L
(relative water deficit) hypotonic loss occurs in combination with a decrease water intake. (infants and elderly)
symptoms: thirst, restlessness, irritability, spasticity, ataxia, mental slowing, seizures, coma, and death
*classified as hypo- hyper- isovolemic |
|
|
Term
| What is hypovolemic hypernatremia? |
|
Definition
decreased ECF and Na
deficit of water more greater than Na deficit
Causes: diarrhea and laxative induced, excessive sweating, diuretics, mannitol
Symptoms: decreased BP, skin turgor, and HR |
|
|
Term
| What is the treatment for hypovolemic hypernatremia? |
|
Definition
resoration of intravascular volume (0.9% NS) and replace water deficit (D5W, 0.45% NaCl, replace over 2-3days)
*need to replace more water than Na. |
|
|
Term
| What is hypervolemic hypernatremia? causes and treatment |
|
Definition
elevated ECF and Na (more Na than water)
causes: renal failure, iatrogenic (we caused it), mineralcorticoid excess
Treatment: replace water deficit D5W and 0.45% NaCl AND diuretic! |
|
|
Term
| What is isovolemic hypernatremia? |
|
Definition
pure water loss
normal Na
causes: diabetes insipidus, skin (fever), iatrogenic
Treatment: replace water deficit, D5W and 0.45% NaCl SLOWLY! |
|
|
Term
| What does iatrogenic mean? |
|
Definition
| caused by us...or a treatment of some kind. |
|
|
Term
| What is potassium? location, concentration, what is it effected by? |
|
Definition
primarily an intracellular cation
3.5-5mEq/L (plasma)
homeostasis is maintained through:
Na/K pump, changes in arterial pH, medications, renal excretion/absorption |
|
|
Term
| What is hypokalemia? mEq/L and causes |
|
Definition
more common than hyperkalemia
MOD: 2.5-3.5 mEq/L
SEV: <2.5 mEq/L
causes: decreased dietary intake, GI loss, Renal loss, transient hypokalemia, sweat loss |
|
|
Term
| What are the causes of hypokalemia? |
|
Definition
decreased dietary intake
GI loss (vomiting, diarrhea, draining fluids, chronic laxative use)**most common cause, renal loss (diuretics, mineralcorticoid excess, hypomagnesemia, polyuria), Transient hypokalemia (redistribution of K, increase ECF pH, insulin, beta agonist activity(albuterols)) |
|
|
Term
| What are the symptoms of hypokalemia? |
|
Definition
malaise, fatigue, cramps, muscle weakness, polyuria
LOTS of EKG changes!
Arrhythmias! |
|
|
Term
| What is the Oral treatment for hypokalemia? |
|
Definition
| Oral (preferred): liquid K, enteric coated tablets, wax matrix, salt substitutes, K rich foods, K sparing diuretics with other diuretics. |
|
|
Term
| What is the IV treatment for hypokalemia? |
|
Definition
used when oral route is not feasible, or if life threatening
Chloride!
avoid gluconate/dextrose |
|
|
Term
|
Definition
K>5.5mEq/L
mild(5.5-6.5), Mod (6.5-6.9), Sev(>7)
Causes: increased intake,redistribution of K stores from ICF to ECF, pseudohyperkalemia, elevated body stores |
|
|
Term
| What causes hyperkalemia? |
|
Definition
| increased intake, redistribution of K stores from ICF to ECF (acidosis, insulin deficiency, cellular injury), pseudohyperkalemia (falsely elevated by RBC release, falsely elevated in pts with thrombosytocic and leukocytosis), elevated total body stores (ingestion, reduced excretion) |
|
|
Term
| What are the symptoms of hyperkalemia? |
|
Definition
muscle weakness, muscle twitching, nausea, cramping
lots of EKG changes
arrhythmias! |
|
|
Term
| What is the treatment of hyperkalemia? |
|
Definition
moderate-severe hyperkalemia w/ EKG changes requires immediate tx.
1. antagonize cardiac effects (short term)
2. shift K from ECF into ICF (short term)
3. enhance K elimination*** |
|
|
Term
| How would you antagonize cardiac effects in hyperkalemia? |
|
Definition
10-20mls of 10% Ca gluconate IV
Doesnt decrease K levels
may cause hypercalcemia! |
|
|
Term
| how would you shift K in hyperkalemia? |
|
Definition
ECF->ICF
insulin
beta agonists (albuterol)
sodium bicarb (only in severe metabolic acidosis)
**doesnt change K levels! |
|
|
Term
| How would you enhance K elimination in hyperkalemia? |
|
Definition
Na polystyrene sulfonate (Kayxelate)
or
loop/thiazide type diuretics |
|
|
Term
| If you can't get rid of the K fast enough in hyperkalemia, what can you do? |
|
Definition
| hemodialysis (removes faster than peritoneal dialysis) |
|
|
Term
| What is the normal magnesium plasma concentration, location, action, etc? |
|
Definition
normal plasma concentration 1.4-1.75mEq/L
300-350mg/day requirement
resides in ICF
catalyzes/activates 300 enzymes
provides neuromuscular stability
involved in myocardial contraction |
|
|
Term
| What are the causes of hypomagnesemia? |
|
Definition
| excessive GI loss (diarrhea/laxative abuse/NG suctioning/acute pancreatitis), renal loss (primary hypoaldosteronism/medications/diabetic ketoacidosis/renal disorders), inadequate intake (alcoholism/dietary restriction) |
|
|
Term
| What are the symptoms of hypermagnesemia? |
|
Definition
| neuromuscular (tetany, muscle weakness, cramps, tremors, seizures), cardiovascular (EKG changes and arrhythmias) |
|
|
Term
| T/F hypokalemia and hypercalcemia often occurs with hypomagnesemia. |
|
Definition
| False. hypokalemia and hypocalcemia often occur with hypomagnesemia. |
|
|
Term
| What are the treatments for mild and severe hypomagnesemia? |
|
Definition
mild: increase oral intake (mag oxide 400mg (too much mag causes diarrhea)
severe: 2g mag sulfate by slow IV push |
|
|
Term
|
Definition
serum Mg >2mEq/L
causes: renal insufficiency, intake of Mg containing antacids/laxatives in renal compromise pts, IV solns of Mg in obstetric patients |
|
|
Term
| What are the symptoms in Hypermagnesemia? |
|
Definition
| nausea, vomiting, decreased deep tendon reflexes, muscle weakness, HTN, vasodilation, CNS depression, resp. depression, EKG changes, arrhythmias |
|
|
Term
| What are the treatments for hypermagnesemia? |
|
Definition
| D/C Mg containing products, IV loop diuretic/saline infusion. If life threatening symptoms: 10 mEq IV calcium (antagonizes cardiac and respiratory effects) or hemodialysis/peritoneal dialysis. |
|
|
Term
85y/o M: muscle weakness, nausea, cramping, vomiting. FH: renal impairment, recently put on diuretic. [Na: 137, K: 6, Cl: 107, BUN 30, Mg 2, Cr 1.6]
His lab results show that he has:
A. hyponatremia
B. Hypokalemia
C. Hypernatremia
D. Hyperkalemia
E. Hypomagnesemia |
|
Definition
| D. Hyperkalemia (also hypermagnesemia) |
|
|
Term
85y/o M: muscle weakness, nausea, cramping, vomiting. FH: renal impairment, recently put on diuretic. [Na: 137, K: 6, Cl: 107, BUN 30, Mg 2, Cr 1.6]
What kind of diuretics could he be recently put on? |
|
Definition
Potassium-sparing
amiloride
triamterene
spironolactone |
|
|
Term
85y/o M: muscle weakness, nausea, cramping, vomiting. FH: renal impairment, recently put on diuretic. [Na: 137, K: 6, Cl: 107, BUN 30, Mg 2, Cr 1.6]
What medications other than diuretics could have caused this? |
|
Definition
| ACE inhibitors, ARBs, beta-blockers |
|
|
Term
85y/o M: muscle weakness, nausea, cramping, vomiting. FH: renal impairment, recently put on diuretic. [Na: 137, K: 6, Cl: 107, BUN 30, Mg 2, Cr 1.6]
What is the appropriate treatment(s)?
A. Calcium gluconate
B. NS 0.9%
C. Na polystyrene sulfonate
D. water restriction |
|
Definition
| (K and EKG changes, we need to get rid of cardiac effects now) A. Calcium gluconate AND C. Sodium polystyrene sulfonate |
|
|
Term
65y/o M history HNT, developed hyponatremia after 2 wks of HCTZ. Has fatigue, weakness, dizziness and nausea. [Na 115, K 3.7, Cl 100, BUN 15, Mg 2.1, Cr 1, glucose 105, BP 85/60]
He has which of the following?
A. isotonic hyponatremia
B. hypertonic hyponatremia
C. hypovolemic hyponatremia
D. Hypervolemic hypo natremia
E. isovolemic hyponatremia |
|
Definition
diuretic: low volume
Na: low
C. hypovolemic hyponatremia |
|
|
Term
For a patient with hypovolemic hyponatremia, what would be the best Na replacement therapy? (Na 116mEq/L)
Increase the serum Na at safe rate defined as a change...
A. no greater than 18-20mEq/L within the first 24hrs.
B. no greater than 16-20mEq/L within the first 24 hrs.
C. no greater than 12-16mEq/L within the first 24 hrs.
D. no greater than 8-12mEq/L within the first 24 hrs. |
|
Definition
| D. Raise serum Na at a safe rate defined as a change no greater than 8-12mEq/L within the first 24 hours. (more would throw them into neurological dysfunction!) |
|
|
Term
| What happens when you raise/lower sodium concetrations too fast? (in hypo- or hypernatremia) |
|
Definition
| neurological problems, that could become permanent. |
|
|
Term
65y/i M with liver cirrhosis, has increasing edema and significant weight gain. [Na 125, K 3.7, Cl 100, BUN 15, Mg 2.1, Cr 1, glucose 105, 265mOsm/kg]
He has which of the following:
A. isotonic hyponatremia
B. hypertonic hyponatremia
C. hypervolemic hyponatremia
D. isovolumic hyponatremia |
|
Definition
| C. hypervolumic hyponatremia |
|
|
Term
65y/i M with liver cirrhosis, has increasing edema and significant weight gain. [Na 125, K 3.7, Cl 100, BUN 15, Mg 2.1, Cr 1, glucose 105, 265mOsm/kg]
What would be the most appropriate treatment?
A. hypertonic saline 1-2mL/kg/hr
B. NS 0.9% at 200-300mL/hr
C. D5W or 0.45% NaCl
D. Water and sodium restriction
E. No action needed |
|
Definition
D. Sodium and water restriction
--dont use hypertonic saline because it is only used for head trauma patients and in severe hyponatremia. |
|
|
