Lab Values: K+, Cl-, Na+ Flashcards
what is the most abundant electrolyte in the ICF?
K+
what is the most abundant electrolyte in the ECF?
na+
what are electrolytes responsible for?
fluid balance
nerve impulses
muscle contractions
acid-base balance
electrolytes are _______ ___________ particles
electrically charged
the ECF consists of what?
the interstitial fluid and plasma
cations have a ________ charge
positive
anions have a _________ charge
negative
what kind of protein is the sodium potassium pump?
a carrier protein
what kind of transport os the sodium potassium pump?
active transport
what is used to power the sodium potassium pump?
1 phosphate from ATP
what is the exchange in the sodium potassium pump?
3 Na+ ions exit to ECF for every 2 K+ ions that enter ICF
why is the electrical charge caused by the exchange of Na+ and K+ so important?
the ECF has a positive charge used in the generation of nerve impulses. this “voltage” is also called membrane potential
sodium levels are regulated by what?
the kidneys
what is the normal range for sodium?
135-145 mEq/L
sodium controls what?
water distribution and fluid balance
serum Na+ levels reflects the _________ of Na+ to water
ratio
sodiums functions include (5):
-ECF osmolality
-water distribution btw ECF and ICF
-maintain BP
-transmission of nerve impulses
-muscle contractility and -acid-base balance
what does osmolality determine?
the concentration of dissolved particles in a fluid, such as blood or urine. can measure the amount of sodium, chloride and potassium
what is hypovolemic hyponatremia?
both Na+ and water lost but more Na+ lost than water
what are the four causes of hypovolemic hyponatremia?
excessive sweating
vomiting
diarrhea
diuretics
what is hypervolemic hyponatremia
more water gained than Na+
what are the causes of hypervolemic hyponatremia?
fluid volume overload from:
1. kidney failure
2. liver failure
3. heart failure
what are the symptoms of mild hyponatremia?
headache
altered mental staus
muscle weakness/ cramps
what is a common sign of hypervolemic hyponatremia?
edema
what are the s/Sx of severe hyponatremia?
SALT LOSS
Stupor/coma
anorexia
lethargy
tendon reflexes
limp muscles
orthostatic hypotension
seizures
stomach cramping
what does iso mean?
equal
what are the interventions for hypovolemic hyponatremia?
withhold diuretics
replace sodium and water
isotonic IV therapy
what are the interventions for hypervolemic hyponatremia?
fluid restriction (edema)
tx of underlying disorder (HF, renal, hepatic)
what are the nursing implications for hyponatremia?
-assess : neuromuscular
-precautions: fall and seizure
-edema: monitor I/O and weight
what level is considered hypernatremia?
> 145mEq/L
what are the two main ways to cause hypernatremia?
greater water loss than Na+
excessive Na+ gain
if serum level is high it is called _________ and if serum level is low it is called __________?
hyperosmolality
hypoosmolality
how can you have greater water loss than Na+ in hypernatremia?
dehydration
inadequate water intake
high fever
diarrhea (watery)
how can you have excess Na+ gain in hypernatremia?
-excess IV fluids containing Na+
-excess oral intake or Na+ (seawater, diet)
what are hypernatremia symptoms?
FRIED SALTS
Flushed skin
restless
intense thirst
lethargy
decreased urine output
skin is dry
agitation
low grade fever
thirst, sticky mucous
seizures/coma
what are the interventions for hypernatremia?
restrict Na+ intake
replace fluids PO or IV (hypotonic: low Na+ fluids)
what are the dehydration related symptoms of hypernatremia?
flushed skin
intense thirst
decreased urine output
skin is dry
thirst/sticky mucous
what are the nursing implications for hypernatremia?
-neuromuscular assessment
seizure and fall precautions
measure I/O (urine color/ amt)
where is the majority of potassium stored?
muscles
how is potassium eliminated?
kidneys eliminate 90%
what is k+ relationship with aldosterone?
inverse relationship
aldosterone increases Na+ and water reabsorption and K+ gets excreted
what is out main source of K+?
diet
what is the normal range for K+?
3.5-5 mEq/L
how is K+ related to glucose?
insulin moves K+ and glucose into the cell by increasing the # of sodium and potassium pumps
what is another way to say reabsorption?
retained
what are the 4 causes of hypokalemia?
drugs (laxatives, diuretics)
inadequate intake
too much insulin (moves K+ into cells)
heavy fluid loss (vomiting)
what is paresthesis?
pins and needles sensation
how is mg+ related to low K+?
direct relationship, if Mg+ is low then so is K+
how does vomiting influence K+ levels?
heavy fluid loos will cause alkalosis from loss of HCl-
in order to fix this the body moves K+ (neutral) into the cells and H+ (acid) out of the cells to decrease serum pH
what are dietary sources of K+?
BOATS
bananas
oranges
avocados
tomatoes
spinach (source of vit K and K+)
what are the symptoms of hypokalemia?
5 Ls “slowing down”
neurons less excitable and action potentials inhibited (lack of repolarization)
- leg cramps
- limp muscles, ↓reflexes, paresthesis
- low, shallow respirations
- lethal cardiac dysrhythmias
- slow GI motility (ileus, nausea, constipation)
what are interventions for hypokalemia?
hold diuretics, laxatives
infuse K+ if severe
increase K+ in diet or supplements
what are the nursing implications for hypokalemia?
assess:
motor function (and strength)
reflexes
respiratory function
heart rhythm monitored
bowel sounds
what are 5 Hyperkalemia causes?
- renal failure (common)
- excessive K+ intake
- drugs (K+ sparing diuretics)
- muscle breakdown
- acidosis
why does acidosis cause hyperkalemia?
loss of HCO3- due to diarrhea causes a relative abundance of H+ acid ions. in order to fix this the body send the H+ into cells and the K+ into ECF causing hyperkalemia but raising pH
what are some symptoms of hyperkalemia?
↑cell excitability
⇣cardiac depolarization
DEATH
Decrease HR
Early muscle
twitching→weakness
Arrhythmias
Tummy trouble
Hypotension
what are 5 hyperkalemia interventions?
-restrict K+ foods
-ID K+ sparing meds and
hold
-diuretics to promote
excretion
-PO meds to excrete K+
-IV insulin w/ dextrose
(move K+ into cell)
what are nursing implications for hyperkalemia?
-🖤 rhythm monitored
-muscle function and
strength
-bowel function and type
of stool
-BP
-Glucose levels (if insulin
given)
what is the range of normal chloride levels?
95-105 mEq/L
what are the functions of chloride?
-acid-base balance
-a component in HCl-
-direct relationship w/ Na+
-inverse relationship with
HCO3-
how are Cl- levels regualted?
-kidneys excrete Cl-
-also excreted in sweat and
gut juices
how does metabolic alkalosis cause hypochloremia?
metabolic alkalosis caused by excessive loss of HCl-
what are some hypochloremia causes?
-GI loss (vomiting, NG suction)
-diuretics
-fluid volume overload
-metabolic acidosis
what are the symptoms of hypochloremia?
assoc. w/ the cause of hypoCl-
ex: Na+ low = Cl- low
SALT LOSS
Stupor/coma
anorexia
lethargy
tendon reflexes
limp muscles
orthostatic hypotension
seizures
stomach cramping
what are the interventions for hypochloremia?
-monitor Na+, Cl-, and
HCO3- and K+ levels
- Sodium chloride IVFs
-intake of Cl- rich foods
(salty foods)
why should you monitor K+ levels during metabolic alkalosis?
hypokalemia can be caused by the body’s fix for alkalosis (exchange of K+ for H+)
why should you monitor HCO3- and Cl- levels during metabolic alkalosis?
because there is an inverse relationship btw Cl- and HCO3- (to maintain the anion gap)
what are the nursing implications for hypochloremia?
-Assess for hypoNa+ and
Sxs
-monitor K+ level (↓in
alkalosis)
-safety precautions
-I/O, weight, VS
what is metabolic acidosis?
loss of HCO3- (strong base) due to diarrhea causes blood to become acidic
what are the causes of hyperchloremia?
-assoc. w/ excess Na+ or
IVF high in Na+ (Na+Cl-)
-not drinking enough water
or loss of fluid
-metabolic acidosis
why does metabolic acidosis cause hyperchloremia?
bc the more HCO3- lost the more Cl- is retained by the kidneys to maintain the anion gap. causing hyperchloremia
what are the symptoms of hyperchloremia?
ID cause
similar to hyperNa+
FRIED SALTS
Flushed skin
Restless
Intense thirst
lEthargy
Decreased urine output
Skin is dry
Agitation
Low grade fever
Thirst/sticky mucous
Seizures/coma
what are the 3 interventions for hyperchloremia?
-monitor Na+, Cl-, and
HCO3- levels
-hold infusions w/ NaCl
-limit intake of Na+ foods
(also contain Cl-)
what are the 4 nursing implications for hyperchloremia?
-assess for hyperNa+ S/sx
-monitor K+ level
(↑acidosis)
-safety precautions
-I/O, weight and VS
what is normal body pH?
7.35 - 7.45
why is bicarbonate a base?
it accepts H+ ions and neutralizes acids
why is H+ an acid?
loses H+ in water
the more H+ ions the more acidic
what role does K+ play in acid-base balance?
it exchanges with H+ into or out of ECF and ICF
