electrolytes

the lecture from hell

what is the definition of electrolytes?

substances the dissociate into ions in solution and are able to conduct electrical currents

anions have a _____ charge and cations have a ______ charge. An anode has a _____ charge and a cathode has a ____ charge

negative, positive, positive, negative

what are the eight major electrolytes?

sodium, potassium, chloride, bicarbonate, calcium, magnesium, and sulfate

besides electrolytes what other 2 types of molecule carry charge?

amino acids and proteins

what three electrolytes maintain osmotic pressure?

sodium, potassium, and chloride

what four electrolytes maintain blood pH?

bicarbonate, sodium, potassium, chloride

what four electrolytes regulate the activity of muscles and the heart?

potassium, calcium, magnesium, and chloride

what two electrolytes are enzyme cofactors?

magnesium and calcium

what two electrolytes are activators of coagulation and complement?

calcium and magnesium

what two electrolytes produce ATP from glucose?

magnesium and hydrogen phosphate

what three electrolytes are involved in bone formation?

calcium, hydrogen phosphate, and magnesium

how are electrolytes gained?

mostly through diet but calcium hydrogen phosphate and potassium all have large reservoirs in the body to pull from

how are electrolytes lost?

vomiting, diarrhea, excessive sweating

what is the most abundant EXTRACELLULAR cation?

sodium

_____ is the most abundant EXTRACELLULAR cation. it accounts for ____% of extracellular cations. Intracellularly _____ is present in very _____ levels. It is transported in the plasma as a _____

sodium, 90, sodium, low, free ion

what are the four major functions of sodium in the body?

osmolality of plasma, regulates water movement, acid-base balance, nerve and muscle function

what are the two mechanisms of sodium management in the body?

kidneys and thirst

what hormone controls sodium reabsorption by the kidney?

aldosterone

what hormone controls water excretion by the kidney?

ADH

______ is transported as a ______ in the plasma, its level is maintained in cells by way of the _____ which pushes out 3 _____ for every 2 _____. Only 2% of ______ is found outside of RBC’s.

potassium, free ion, sodium potassium pump, sodium, potassium, potassium

what are the two regulatory methods for maintaining potassium levels?

kidney, diet

in the dct potassium is exchanged for sodium under the influence of what hormone?

aldosterone

what is the most abundant EXTRACELLULAR ANION?

chloride

chloride is the main sidekick of what ion?

sodium

what are the four major functions of chloride?

plasma osmolality, water balance, maintaining blood volume, maintaining acid-base

what are the three regulatory methods for chloride?

kidneys, diet, sweat glands

what are the 5 major functions of calcium?

bone constituent, muscles/heart, coagulation, cell membrane permeability and transport, activating enzymes and complement

what is the most prevalent cation in the BODY?

calcium

for every 1 g/dL decrease in albumin total calcium drops _____ mg/dL

0.8

serum ____ levels are inversely proportionate to calcium levels

phosphate

what six ways are calcium levels regulated?

bones, intestines, renal excretion, PTH, vitamin D, calcitonin

what does vitamin D do in terms of calcium?

tells the intestines to suck up more calcium

what does PTH do in terms of calcium?

PTH is triggered with low calcium levels it robs the bones of calcium and tells the kidney to make more vitamin D to stop calcium reabsorption

what does calcitonin do in terms of calcium?

triggered when calcium level are high it inhibits calcium reabsorption from bones, the kidney, and intestines

is ionized calcium affected by albumin?

no

what disease state is associated with ionized calcium?

parathyroid disease

what does this pattern correlate to: (/\ PTH) (/\ iCa) (\/ Po4) (= TCa)

primary hyperparathyroidism

what does this pattern correlate to: (\/ PTH) (\/ iCa) (/\ PO4) (\/ TCa)

primary hypoparathyroidism

what are the major functions of phosphate?

bones, teeth, forms 2,3-DPG, metabolism, cell membranes, acid-base, ATP/ADP, muscles and nerves, nucleic acids and nucleotides

what are the four regulatory methods for phosphate?

PTH, Calcitonin, vitamin D, growth hormone

what does growth hormone do in terms of phosphate?

increases renal tubular absorption

what are the major functions of magnesium?

co-factor for ATP, co-factor for enzymes, bone structure, calcium reabsorption in intestines, triggers PTH release

what are the three magnesium regulatory methods?

PTH, aldosterone, thyroxine

how does flame photometry work?

coverts anything put inside into elemental form and the color of the flame emitted is specific to the ion present

for flame photometry the greater the concentration of the ion the ___ the emition

greater

how does atomic absorption spectrophotometry work?

a lamp containing a specific ion is shone onto an atomizer, ions in the analyzer that match the ions in the lamplight absorb some of the light reducing the amount of light that reaches the detector

in atomic absorption spectrophotometry the greater the concentration of ions the _____ lamplight that reaches the detector

less

how does potentiometry work for ion concentration measurements?

membranes specific to a particular ion are used

how does coulometry measure ion concentrations? what ion is measured this way?

a constant redox reaction is fueled by ions in solution and the silver ions in the wire, sodium in sweat

sodium has a reference range of ______mmol/L or ______ mEq/L. It can be measured in samples of ____, _____, or _____. It is mostly measured via ____

135-145, 135-145, urine, serum, plasma, ISE

potassium has a reference range of ____ mmol/L or ______ mEq/L. It can be measured in samples of _____, _____, or _____. Measurement is done via _____

3.5-5.5, 3.5-5.5, serum, plasma, urine, ISE

chloride has a reference range of ______ mmol/L or _____mEq/L. It can be measured in samples of _____, _____, _____, or ____. It is measured via ____.

98-108, 98-108, serum, plasma, sweat, urine, ISE

serum total calcium has a reference range of ______, serum ionized calcium has a reference range of _____, samples can be from _____ or _____. ionized calcium must be measured via ____ but total calcium can be measured via _____ or _____ after acidification.

8.6-10.0, 4.6-5.3, serum, plasma, ISE, colorimetric method, AAS

phosphate has a reference range of _____ mg/dL or _____ mmol/L. the sample can be ____ or ____ and must be measured via ______ method

2.7-4.5, 0.87-1.45, serum, plasma, colorimetric

Magnesium has a reference range of _____ mg/dL, the sample can be ______ or ______. hemolysis should be avoided and it should be separated from cells. it should be measured via _____ or ____ method

1.7-2.5, serum, plasma, colorimetric, AAS

what are the causes of pseudo-hyperkalemia?

hemolysis, plasma sitting on cells, platelets, clots, tourniquet left on too long

what are the causes of pseudo-hypernatremia?

high lipids, high protein

what are the causes of too high or too low chloride?

serum/plasma sitting on cells

what type of sample must be used for ionized calcium?

serum or plasma

what are the causes of pseudo-hypermagnesemia?

hemolysis and sitting on cells

what does EDTA do to electrolyte results?

lowers calcium and raises potassium

what does sodium heparin do to electrolyte results?

raises sodium levels

what does sodium citrate do to electrolyte levels?

lowers calcium and raises sodium

what are the causes of hypernatremia?

water loss, diabetes insipidus, Cushing’s disease, excessive intake, cardiac failure

what are the causes of hyponatremia?

renal tubular disease, metabolic acidosis, Addison’s disease, water intoxication, profuse sweating, diarrhea/vomiting/malabsorbtion

what are the causes of hyperkalemia?

renal failure, renal tubular disease, tissue damage, in vivo hemolysis, increased intake

what are the causes of hypokalemia?

diuretics, inadequate intake, prolonged diarrhea/vomiting/malabsorbtion

what are the causes of hyperchloremia?

dehydration, diabetes insipidus, decreased perfusion, excessive intake

what are the causes of hypochloremia?

diarrhea/vomiting/mal absorption, excessive sweating, chronic pyelonephritis, aldosterone deficiency

what is sweat chloride used to detect? what faulty gene is responsible? How is sweat collected? How is the sweat tested?

cystic fibrosis, CFTR, iontophoresis, coulometry

why is chloride elevated in sweat of CF patients?

cl can’t be reabsorbed

what clinical conditions can cause hypercalcemia?

primary hyperparathyroidism, metastatic cancers with bone involvement, multiple myeloma, nonendocrine tumors, vitamin D overdose, excessive anti-acids

what are the clinical conditions that can cause hypocalcemia?

hypoalbuminemia, primary hypoparathyroidism, hypomagnesemia, steatorrhea, Rickets, Osteomalacia

what are the symptoms associated with hypocalcemia?

neuromuscular hyperexcitability, Tetany, seizures

what are the clinical conditions that can cause hyperphosphatemia?

renal failure, vitamin D overdose, hypoparathyroidism, acute osteoporosis

what are the clinical conditions that can cause hypophosphatemia?

hyperparathyroidism, decreased intestinal absorption, Rickets, Osteomalatia

what are the symptoms associated with hypophosphatemia?

mental confusion

what are the clinical conditions that can cause hypermagnesia?

renal failure, increased intake, dehydration, bone carcinoma

what are the clinical conditions that cause hypomagnesia?

severe illness, decreased intestinal absorption, increased excretion of urine, pregnancy and lactation

what are the symptoms associated with hypomagnesemia?

neuromuscular symptoms, tetany, heart arrhythmias

what is the anion gap?

we measure more anions than cations which looks like a gap where there are more cations than anions

what are the causes of an elevated anion gap?

uremia, ketoacidosis, poisoning, hypernatremia

what are the causes of a low anion gap?

hypoalbuminemia, severe hypercalcemia

what is the formula for calculating anion gap?

AG = (Na + K) - (Cl + HCO3)