Lab Values Flashcards
Sodium-Potassium pump
Sodium ions (Na+) are pumped OUT of the cell and potassium ions (K+) are pumped INTO the cell
*energy to drive the pump is released by hydrolysis of ATP
What is the main cation of ECF , what does it do
Sodium, plays a major role in maintaining the concentration and volume of ECF and influencing water distribution between ECF and ICF, important in generating and transmitting nerve impulses, muscle contractility, and regulating acid-base balance
What does serum sodium levels reflect
The ratio of sodium to water
(Not necessarily the amount of sodium in the body)
ECF osmolarity main determinant
Sodium
Hypertonic imbalance cause
Water to move from inside the cell into the ECF (to dilute the concentrated sodium) causing the cell to shrink
Hypotonic imbalance cause
Causes water to move into the cell, causing the cell to swell
How does sodium leave the body
Through urine, sweat, and feces
(Mainly regulated by the kidneys under the influence of ADH)
What is the most abundant extracellular cation
Sodium
What ere the functions of sodium
-primary determinant in ECF osmolality
-influences water distribution between ECF & ICF
-serum Na+ level reflects the ratio of Na+ to water
-role in maintaing BP
-transmission of nerve impulse and muscle contractility
-acid-base balance
Why should people with Hypertension not have too much salt
Too much salt will increase volume in the intracellular space
Osmolarity
A measurement concentration of molecule per weight of water
*concentration of solutes in the blood
Low soules=low sosmolarity
Low Na+ osmolarity = hypoosmolarity
(Solute concentration is what drives the movement of water)
Hypervolemic hyponatremia
Occurs when the body has an increase in total body water that’s greater than the increase in total body sodium. This causes a marked increase in extracellular fluid volume, which can lead to edema. Common causes include heart failure, cirrhosis, and kidney injury. Treatment includes correcting the underlying cause, restricting sodium and fluids, and using diuretics.
Hypovolemic hyponatremia
Occurs when the body has a decrease in total body water that’s greater than the decrease in total body sodium. This causes a decrease in extracellular fluid volume. Common causes include fluid losses from the kidneys or gastrointestinal tract, such as from diarrhea or overdiuresis. Treatment typically involves normal saline.
Both hypovolemic & hypervolemic hyponatremia are common in
Older adults d/t comorbidities
Multiple Rx
Lack of access to food/water
Lack of thirst
Na+ loss> total body water
Hypovolemic hyponatremia
Total body water gain> Na+
Hypervolemic hyponatremia
What are the causes of hypovolemic hyponatremia
Excessive sweating
Vommiting
Diahrrea
Diuretics
What are the causes of hypervolemic hyponatremia
Fluid volume overload
-kidney failure
-liver failure
-heart failure
(Edema common itch these chronic conditions)
What are the symptoms of hyponatremia
Stupor/coma
Anorexia
Lethargy
Tendon reflexes decrease
Limp muscles
Orthostatic hypotension
Seizures
Stomach cramping
(Headache, altered mental status, muscle weakness and cramps)
How does hyponatremia play a role in nerve impulses
Sodium must be available at normal levels in order to have normal conduction of nerve pulses, if these action potential slow down then symptoms will be present
Orthostatic hypotension
A form of low blood pressure that happens when standing up from sitting or lying down.
Can occur with hyponatremia
Ascites
Ascites is a condition that occurs when fluid collects in spaces in your belly (abdomen). If severe, it may be painful. The problem may keep you from moving around comfortably. Ascites can set the stage for an infection in your abdomen. Fluid may also move into your chest and surround your lungs.
Hyponatremia can cause ascites because
retention of sodium and water to compensate for the low effective circulatory volume resulting in the development of ascites.
(Lack of volume in the ECF, fluid moves out and into the intravascular space which is not functional)
Hypovolemic hyponatremia interventions
With hold diuretics
Replace sodium & water
Isotonic IV therapy
Hypervolemic hyponatremia interventions
Fluid restriction (may have edema)
Tx of underlying disorder (HF, renal, hepatic)
What are the nursing implications for hyponatremia
Neurological assessment
Implement seizure precautions (if severe)
Implement fall precautions
Monitor intake and output
Daily weights if edema present
What is an isotonic IV
Sodium chloride bags aka normal saline, no fluid movement same osmolarity as blood
hypernatremia
Serum sodium is high
High Na+ osmolality (hyperosmolality)
What are the causes of hypernatremia
Greater water loss than Na+
-dehydration (loss of water)
-inadequate water intake
-high fever
-diarrhea (can cause sodium and water loss)
Excess Na+ gain
-excess IV fluids containing Na+
-excess oral intake of Na+ (seawater, diet)
Hypernatremia
Flushed skin
Restless
Intense thirst
lEthargy
Decreased urine output
Skin is dry
Agitation
Low grade fever
Thirst, sticky mucous membranes
Seizures possibly coma
What are hypernatremia interventions
Restrict Na+ intake
Replace fluids PO or IV
What are the nursing implications for hypernatremia
Neurological assesment
Implement seizure precautions if severe
Implement fall precautions
Measuring I & O
Potassium
-most abundant intracellular cation
-diet is main source of
-majority found in muscles (nerve and muscle contractions)
-kidneys responsible for balance (eliminate ~90%)
-may have inverse relationship with Na+ (Ie. aldosterone)
-insulin moves K+ and glucose into the cell
If you have cramps you may be deficient in
Potassium and magnesium
What causes hypokalemia
-Drugs (laxatives, diuretics)
-inadequate intake
-too much insulin (moves K+ into cells)
-heavy fluid loss (ie. vomiting)
>alkalosis shifts K+ into the cells and moves H+ out of cells
If Mg+ is low then what else is low
K+
You need enough Mg+ for K+ to be absorbed otherwise it would just get peed out
What are the symptoms of hypokalemia
“Slowing down”
-Leg cramps
-Limp muscles, decreased reflexes, paresthesias (tingling & numbness)
-Low shallow respirations
-Lethal cardiac dysrhythmias
-sLow GI motility (constipation, nausea, paralytic ileus)
CKD complication with potassium
People with chronic kidney disease are unable to eliminate potassium since 90%of potassium is excreted by the kidneys, they will need dialysis and medications to remove the potassium
Insulin increases the number of
Increases the number of pumps, helps move potassium and glucose into the cell
Why do things slow down in hypokalemia
The lack of potassium inhibits action potentials, lack of repolarization
(Similar to hyponatremia)
What are the interventions for hypokalemia
-infuse K+ if severe
-increase K+ in diet (bananas or supplements)
-hold diuretics, laxatives
(Except for potassium sparing drugs, metimusal, and stool softeners bc they don’t cause fluid and electrolyte imbalances)
What foods are high in potassium
Bananas
Oranges
Avocados
Tomatoes
Spinach (vitamin K & K+)
What are the nursing implications for hypokalemia
-motor function & strength
-reflexes
-respiratory function
-heart rhythm monitored
-bowel sounds
What are the causes of hyperkalemia
-renal failure
-excessive K+intake (through food or supplements)
-drugs (potassium-sparing diuretics)
-muscle breakdown
-acidosis (K+ ions move out of the cells and H+ moves in)
Hyperkalemia symptoms
-increase cell excitability to nerves and skeletal/smooth muscles
-decreases cardiac depolarization
Decrease HR
Early muscle twitching leading to weakness
Arrhythmias
Tummy trouble (diarrhea)
Hypotension
D/t ECG changes
How can insulin causes changes in potassium
Too much insulin can cause hypokalemia bc it adds more sodium potassium pumps which move potassium and glucose into the cells, lowering the blood sugar and blood potassium
Rhabdomyolysis
Rhabdomyolysis is the breakdown of muscle tissue that leads to the release of muscle fiber contents into the blood.
Can cause hyperkalemia bc it releases K+ into the blood
Hyperkalemia interventions
-restrict K+ food
-identify K+ sparing meds
-may need diuretics to promote excretion
-PO meds to excrete K+
-IV insulin with dextrose (moves K+ into the cell)
Nursing implications for hyperkalemia
Assess:
-heart rhythm monitored
-muscle function and strength
-bowel function and character of stool
-blood pressure
-(Glucose level if insulin is used)
Kayexcelate is used when
Patient is hyperkalemia and needs to poop potassium
Available PO & enema
Hyperkalemia causes the bowel to be
Hyperactive and cause “tummy trouble”
An cause abdominal pain, diarrhea, nausea and vomiting
Chloride (Cl-)
-most abundant anion outside the cell
Chloride functions
-maintains acid base balance
-a component of HCL- acid
-Na and Cl- congregate outside the cell
-inverse relationship with HCO3
If chloride is low then sodium is
Also low and vice versa
Chloride is regulated by
Primarily the kidneys which secret Cl-
Also sweat and gut juices
If chloride goes into the cell then
HCO3 goes out because there is an exchanger
What are the causes of hypochloremia
-GI losses (vomiting, prolonged NG suction)
-diuretics
-fluid volume overload
-metabolic alkalosis (excessive loss of gastric HCL-) (if less CL- is available, then more HCO3- is retained by the kidneys)
What are the symptoms of hyopchloremia
-associated with the cause for hypoCl- (identify the cause)
-similar to hypoNa+ (salt loss)
What is an example of a diuretic
Furosemide
What are the interventions for hypochloremia
-monitor Na+, Cl-, and HCO3- levels
-monitor K+ level (low K+ impairs Cl- renal absorption)
-sodium chloride IVFs for replacement
-increase intake of foods rich in Cl- (salty foods)
Alkalosis will shift K+
K+ into the cells and H+ out of the cell
Nursing implications for hypochloremia
-assess for hypoNa+ Sxs (related to neuromuscular, neurological, and musculotskeletal)
-monitor K+ level (may decrease in alkalosis)
-implement saftey precautions
-I & O, weight, VS
What are the causes of hyperchloremia
-associated w/ excess Na+ intake of IVF high in Na+ (Na+Cl-)
-not drinking enough water or loss of fluid
-metabolic acidosis (HCO3- loss d/t diarrhea) (the more HCO3- lost, the more Cl- is retained by the kidneys)
What are the hyperchloremia symptoms
-associated with the cause for hyperCl- (identify the cause)
-similar to hyperNa+ (FRIED SALTS)
What are the interventions for hyperchloremia
-monitor Na+, Cl-, and HCO3- levels
-hold infusions with sodium chloride
-limit intake of Na+ foods (also contain Cl-)
What are the nursing implications for hyperchloremia
-assess for hyperNa+ SXs
-monitor K+ level (may increase in acidosis)
-implement safety precautions’
-I & O, weight, VS
