Lecture 6.1 - Electrolyte Imbalances Flashcards
Which demographics are most vulnerable to dehydration from vomiting?
Older adults, children, and infants
What is the normal range for sodium in blood?
136-145 mEq/L
What cation is most common in ECF?
Na makes up 90% of ECF, being the main factor in determining ECF volume
changes in K effect the heart. What do changes in Na do?
Effect the brain
What can cause hypernatremia? What can it lead to and how does the body protect from it?
–> Excessive intake
–> Diabetes insopidus
–> Renal failure
–> Cushing Syndrome
Causes hyperosmolarity leading to cellular dehydration
Protected with thirst centre in hypothalamus
What are the manifestations for moderate and severe hypernatremia?
Moderate: Confusion, thirst, dry mucous membranes, low urinary output
Severe: HTN, tachycardia, flushed skin
–> Restlessness, agitation, confusion, seizures, coma
–> Hyper-reflexia, muscle twitching
Nausea, vomiting
–> Poor tissue turgor
How do we correct hypernatremia?
Fluids, diuretics to increase sodium output
–> Monitor daily weights, neuro deterioration, fluid imbalance
What are some nursing diagnoses associated with hypernatremia?
Electrolyte imbalance
Risk for injury: seizures
What is the normal potassium level?
3.5-5.1 mmol/L
What is the major ICF cation?
Potassium
Sodium is necessary for:
Maintaining fluid levels and regulating blood fluids to prevent low blood pressure.
Helps muscles contract, and sends nerve impulses throughout the body
Potassium is necessary for:
–> Transmission and conduction of nerve and muscle impulses
–> Cellular growth
–> Maintain cardiac rhythms (depolarizes and generates APs, low K is shown as a flat T wave in cardiac rhythm)
–> Regulates protein synthesis, and glucose storage and use.
K administration should never exceed what? Why?
20 mEq/hr
–> Prevents hyperK + cardiac arrest
–> Burns when infusing
What is the normal range for calcium? What is is necessary for?
2.10-2.75 mmol/L
–> Blood clotting
–> Muscle contraction (including myocardium)
–> Nerve function
What is the normal serum range for magnesium?
0.65-1.05 mml/L
What is the normal serum level for phosphorus? What does it do?
1.0-1.5 mmol/L
–> Activates vitamins and enzymes, forms ATP, and assists in cell growth and metabolism
–> Maintains acid-base balance
–> Maintains calcium homeostasis.
What are the different kinds of fluid spacing?
First Spacing
–> Normal distribution of ICF and ECF
Second Spacing
–> Abnormal accumulation on interstitial fluid (edema)
Third Spacing
–> Fluid accumulation in a part of the body not easily exchanged with ECF and in transcellular space
–> Fluid fills cavity and compresses soft structures, resulting in ascites, pleural effusions, pericardiac effusion or tamponade
We have to have a normal ____ before administering IV P-dye
Creatinine - verifies kidney function
What is pOSM?
Serum osmolarity by weight
What is an eGFR?
Creatinine clearance/24 hours to measure kidney function
What does ACTH do?
Triggers the release of aldosterone –> Sodium reapsorption
What does ADH do?
Signals for water reabsorption in the renal tubules/collecting ducts.
What does renin do?
Signals for Ang I (+ ACE) –> Vasoconstriction and aldosterone
What are some potential causes for hyponatremia?
Excessive loss through sweat, GI loss, or renal dysfunction.
Excessive H2O gain
What are the manifestations of hyponatremia?
HypoTN
Seizures, decreased muscle tone, twitching, tremors, weakness
V&D, cramping, anorexia
How can hyponatremia be treated?
Hypertonic IVF and fluid restriction
–> Consume salty food
Monitor for neuro and BP changes
What might cause hyperkalemia?
Massive cell destruction - such an in traumatic injury, severe infection, burns or anything that shifts ICF to ECF
Drugs: K-Sparing (Spironolactone, amiloride), ACE Inhibitors
Impaired renal excretion - renal failure most common
What are the manifestations of hyperkalemia?
Oliguria, renal failure
Addison’s disease, brady, arrhythmias
Cramping leg pain, abd cramps or dirrhea.
How is hyperkalemia treated?
Monitor: ECG
Hold K intake, use loop diuretics to excrete it.
Force K back into ECF with insulin or sodium bicarb
Calcium gluconate can reverse membrane effects of elevated ECF K.
Dialysis.
What are some causes of hypokalemia?
GI/renal losses
Mg deficiency
Metabolic alkalosis
Manifestations of hypokalemia
Cardiac arrest/arrhythmias
Skeletal muscle weakness, oliguria
Decreased GI motility and impaired regulation of arteriolar blood flow.
What treatment can be used for hypokalemia?
Diet - K rich foods
K supplementation
–> IV should not exceed 10-20 mEq/hr to prevent hyperK and CA, and to decrease pain
What can cause hypercalcemia?
Hyperparathyroidism (most common)
Malignant bone disease (cancer)
Vit D overdose
Prolonged immobilization
Excessive supplements/antacids
What are some manifestations of hypercalcemia?
Kidney stones, muscle weakness, decreased reflexes.
Decreased memory + Fatigue
Personality changes and disorientation
How can hypercalcemia be treated?
Calcitonin, loop diuretics, mobilization, dialysis.
Oral fluids 3-4 liters a day or isotonic IV
What causes hypocalcemia?
Renal failure, hypothyroidism
multiple blood transfusions
Alkalosis
What are some manifestations of hypocalcemia?
Trousseau + Chvostek’s sign
Laryngeal stridor
Tingling around the mouth or extremities
Muscle numbness
How can hypocalcemia be treated?
Calcium (not IM)
Diet rich in protein, calcium, vitamin D
Anticipate tracheostomy
What is Trousseau’s sign?
When a BP cuff is inflated 220-230 mmHg and the forearm and hand flex
Indicative of hypocalcemia
What is Chvostek’s Sign?
When tapping on the cheek results in muscle spasm
Indicative of hypocalcemia
What are some causes of hypermagnemesia?
Increased intake w renal insufficiency + renal failure
Adrenal insufficiency
What are some manifestations of hypermagnesemia?
Brady/hypo
Impaired reflexes
Somnolence
Respiratory + cardiac arrest
How can hypermagnesemia be treated?
IV calcium gluconate/chloride
Fluids to promote excretion
What can cause hypomagnesemia?
Chronic alcoholism
Prolonged fasting + Prolonged TPN w/o supplementation
GI loss + diuretics
DKA
What are manifestations of hypomagnesemia?
Skeletal muscle weakness and hyperactive tendon reflexes. Painful contractions
Numbness + tingling
Decreased GI motility
What treatment can help hypomagnesemia?
Supplementation and diet: nuts, peanut butter, bananas
Monitor vitals
IV but must be under 1g/h
What rate must magnesium be administered IV?
1 g/h max
What might cause hyperphosphatemia?
Excessive intake or renal failure
What are the manifestations of hyperphophatemia?
Same as hypocalcemia
–> Muscle cramps, tingling, numbness
–> Joint and bone pain
Rash and pruritis
How is hyperphosphatemia treated?
Diet low in phosphorus:
–> Pasta, bread, rice
–> Limited meat
–> Dairy substitutes
What might cause hypophosphatemia?
Alcohol withdrawal
Recovery from DKA + glucose administration
Malabsorption syndrome + TPN
What are the manifestations of hypophosphatemia?
Decreased cardiac output, weak peripheral pulses
Skeletal muscle weakness
How is hypophosphatemia treated?
Diet high in phosphorus: meats, fish, nuts, beans, dairy products
Vit D supplements
Oral or IV calcium
Sodium phosphate
What electrolyte imbalances can be caused by renal failure?
HyperNa, HyperMg, Hyperphosphatemia
HypoCa
What electrolyte imbalances can be caused by TPN?
Hypo magnesium and phosphate with malabsorption syndrome
Which electrolyte imbalances cause hyperreflexia?
Hyper: Na, Phosphate
Hypo Mg, Hypo Ca results in trousseau and Chvostek
Which electrolyte imbalances cause muscle weakness?
Hypo: Na, K, Mg
What is the normal bicarb range?
22-29 mEq/L
What is the normal Hgb level?
120-180 g/L
What is the normal WBC?
4.5-11.0 x 10^9/L
ACE inhibitors can cause which electrolyte imbalance?
hyperkalemia
What is the most common cause of renal failure?
Hyperkalemia
Magnesium deficiency can cause which other electrolyte imbalance?
hypokalemia
Alkalosis can cause which electrolyte imbalance?
HypoK, HypoCa
Which drug can reverse membrane effects during hyperkalemia?
Calcium gluconate
Which drugs can force potassium from the ECF to ICF?
Insulin and sodium bicarbonate
Prolonged immobilization can lead to which electrolyte imbalance?
hyperCa
Multiple blood transfusions can lead to which electrolyte imbalance?
HypoCa
–> Ca is necessary for clotting factors
Which electrolyte imbalances can lead to tingling around the mouth or extremities?
HypoCa, Hyperphosphatemia, and hypoMg
The symptoms of hyperphosphatemia look like what other imbalance?
Hypocalcemia
Laryngeal stridor can occur with which electrolyte imbalance?
Hypocalcemia
–> Anticipate tracheostomy
Chronic alcoholism can lead to which electrolyte imbalance?
Hypomagnesemia
TPN without supplementation can lead to which deficiency?
Hypophosphatemia