Electrolytes and Acid Base Balance Flashcards
Definition of Electrolytes
Substance that ionize (dissociates) in blood stream and body fluids
Examples of Electrolytes
Acids (H+)
Bases (HCO3-, PO4-2)
Inorganic Salts (K+, Na+, Cl-)
Mineral Ions (Mg2+, Fe2+, Fe3+, Ca2+)
Electrolytes Function
Maintain osmotic pressure of body fluid compartments
Regulate osmotic movement of H2O
Acid-Base Regulation
Found in tissues
Co-enzymes
Neuromuscular reactions
Imbalances in Electrolytes Caused By
Vomiting
Diarrhea
Sweating
Kidney Loss
Hormonal Imbalance
Acid-Base Imbalance
Tissue Destruction
Electrolyte Panel Ordered
Called “lytes”
Na+
K+
Cl-
HCO3- (noted as TCO2 on Blood Gas Report)
Calculated by Anion Gap
Sodium Function
Create Osmotic Pressure
Most Abundant in ECF - Major Extracellular cation
Essential for electrical activity of neurons and muscle cells
Hormonal Regulation of Na and H2O
Aldosterone
- controls Na+ reabsorption by kidneys
Juxtaglomerular apparatus turns on renin-angiotensin system
Decrease Aldosterone Production
Addison’s Disease
Increase Aldosterone Production
Cushing’s Disease
Hyponatremia
Decreased Plasma Na+
Associated with regulation of blood volume
Skin turgor, Venous Pressure, and Urine Na+ concentration
Hypovolemic Depletion Hyponatremia
Result of excess Na loss and excess H20 loss
Renal Loss Hypovolemic
Diuretics
Primary or secondary Addison’s disease
Non-renal loss Hypovolemic
GI loss from vomiting or diarrhea
Skin loss from burns or trauma
Hypervolemic Dilutional Hyponatremia
Relative change in measured Na+ due to increased H2O volume
- Syndrome of inappropriate ADH secretion
- Generalized edema (congestive heart failure, cirrhosis, nephrotic syndrome)
- Uncontrolled diabetes (high blood glucose) mellitus
Hypernatremia
Increased Plasma Sodium
Result of excess water loss or Na+ gain (rare)
Fluid loss of Hypernatremia
Loss of fluid by: GI tract, excessive sweating, hromone disorder
Diabetes insipidus
Absolute Na+ Gain Hypernatremia
Ingestion or infusion of NaCl or NaHCO3
Hyperaldosteronism
Acute Renal Failure
Function of Potassium
Creates Osmotic pressure in ICF
Must abundant cation in ICF
- Major Intracellular Cation
Electrical activity of neurons and muscle cells
Hydrogen Ion buffering
Kidney-Aldosterone Regulation Potassium
Decreased Plasma concentration by increasing rate of K+ secretion in the proximal convoluted tubules and duct
Cellular breakdown increase K+ released
Tied to H+ during metabolic acidosis
Effect of K+ on Heart
Increased plasma slows heart rate by decreasing resting membrane potential of heart
Decreased extracellular, causes myocardial excitability
Critical high K+ levels
Cause Cardiac shutdown
Too much Potassium
Critical low K+ levels
Causes arrythmia
Hypokalemia
Decreased plasma K+
Causes of Hypokalemia
Excessive GI loss, N-G tube, diarrhea, and laxative abuse
Renal losses hyperaldosteronism, renal tubular acidosis
Decreased dietary intake
Increased cellular uptake in alkalosis
Insulin excess
Symptoms of Hypokalemia
Muscle weakness
Cardia arrhythmia
Paralysis
Hperkalemia
Increased plasma K+
Causes of Hyperkalemia
Increased dietary intake
Increased tissue destruction
Altered cellular uptake in acidosis
Insuling deficiency
Impaired renal excretion in renal problems & hypoaldosteronism
False Cause of Hyperkalemia
Hemolyzed blood sample