Electrolytes Flashcards
Active Transport:
mechanism that requires energy to move ions across cellular membranes
Electrolytes:
Ions capable of carrying an electric charge (anions or cations)
Passive Transport:
passive movement of ions across a membrane (diffusion)
Osmolality:
physical property of a solution that is based on the concentration of solutes per kg of solvent
law of electroneutrality
Sum of all positive ions (cations) must equal the sum of negative ions (anions) to maintain electrical neutrality in the plasma.
Sodium:
function, abundance, location, and regulation
Abundance: Most abundant Cation (90%)
Location: Extracellular (plasma)
Regulation:Kidney (conserves/excretes… RAAS)
Function: maintain osmotic pressure and water distribution (nerve/muscle impulses)
Potassium:
function, abundance, location, and regulation
Abundance: Most abundant Intracellular cation
Location: Intracellular
Regulation: Kidney
Functions: regulate neuromuscular excitability and Contraction of heart
Intracellular fluid volume
H+ concentration
Chloride:
function, abundance, location, and regulation
Abundance:Major extracellular anion
Location: Extracellular
Regulation:Ascending loop of henle / sweating
Functions: Maintain Osmotic pressure, hydration, electric neutrality
CO2
function, abundance, location, and regulation
Abundance: 2nd most abundant extracellular anion
Location: Extracellular (plasma)
Regulation:Kidneys/Lungs
Function: blood buffering system
Name the two main water compartments in the body and their constituents.
Extracellular Fluid: Fluid outside of the cells (plasma)
Sodium (Na)
Chloride (Cl)
Bicarbonate (HCO3
Intracellular Fluid: Fluid inside of the cells
Potassium (K)
Magnesium (Mg)
Calculation for Anion Gap
Anion Gap (AG) = (Na + K) - (Cl + CO2)
Normal Range of Anion Gap and significance of for discrepancies
High AG (mult pts) = analytical error High AG (single pt) = possible metabolic issue Low AG = analytic error
What causes interference for measuring electrolytes?
Hemolysis
Ion Selective Electrode for Sodium (Na)
Glass Ion Exchange Membrane
100x more sensitive for Na
Ion Selective Electrode for Potassium (K)
Valinomycin Membrane
10000x more selective for K
Ion Selective Electrode for Chloride (Cl)
Solid state Chloride electrode
Ion Selective Electrode for CO2
glass pH electrode
(gas permeable silicone membrane)
Flame Photometry
Electrolyte Quantification
Quantitate Na and K simultaneously
Internal Li Standard
Colorimetric reading at 525nm of red ferric thiocyanate complex
Acidification of sample converts to CO2 gas and measures
Sodium: Normal & Critical Values
Normal: 135 – 145 mEq/L
Critical: < 120 mEq/L
> 155 mEq/L
Potassium: Normal & Critical Values
Normal: 3.4 – 5.0 mEq/L
Critical: < 2.7 mEq/L
Chloride: Normal & Critical Values
Normal: 95 – 110 mEq/L
Critical: < 85 mEq/L
> 115 mEq/L
CO2: Normal Values
Normal: 23 – 29 mEq/L
Anion Gap: Normal Value
10 – 20 mEq/L
State the relationship between K+ and H+ in the body.
- K+ and H+ function towards blood buffering to ideally 7.4 pH
- Interference of K/H blood buffering leads to an acid/base imbalance
