chem rotation lec2

what is ISE

ion selective electrode measures activity to determine concentration of electrolyte based on the measurement of potential voltage that changes

what does the internal solution of the ISE contain

KCl

what is the selective part of the ISE

the membrane

the liquid and polymer electrodes are associated with what analyte

potassium (valinomycin coated)

the solid state membrane is associated with what analyte

(single crystals or pellets of salt) chloride

the glass membrane is associated with what analyte

pH meter and sodium

the gas sensing electrodes are associated with what analyte

CO2

what are eletrolytes

ions capable of carrying a charge (cation or anion)

what are the functions of electrolytes

regulate osmolality, maintain acid base balance, aid in enzyme activation, involved in coagulation, regulating neurotransmission

describe sodium and what hormone its influenced by

extra cellular cation, maintains osmotic pressure, regulated by aldosterone (kidney)

what does aldosterone do

keep sodium at the expense of potassium

how does the body regulate sodium

water intake, ADH, and aldosterone

what is hyponatremia and what causes it

low sodium; caused by decreased aldosterone, prolonged vomit/diarrhea, severe burns, and increased water retention, SIADH, high ADH, and excess water intake

what is SIADH

syndrome of inappropriate ADH, excreting to much ADH causing dilutional hyponatremia and fluid overload/retention

what are the two main pathways we loose sodium

renal: through kidneys (in urine) or extrarenal: vomit/diarrhea/burns

describe hypernatremia and what is its caused from

high sodium (more than 150); to much water loss, decr water intake, vomit/diarrhea, eating to much salt, hyperaldosteronism, infusion of hypertonic saline

describe potassium and what its infuenced by

intracellular ion (20x greater in the cells) it in influenced by insulin ("promoter" K into cells and incr na/k activity) and aldosterone

what are the main funtions of potassium

regulation of neuromuscular excitability and contractions of the heart, major effect of conc of skeletal and cardiac muscle

where is potassium reabsorbed

in proximal tubules of kidneys (could also be excreted into urine)

describe hypokalemia (reasons)

low K; GI isssues, urinary loss, incr cellular uptake, hyperaldosteronism

what are symptoms of hypokalemia

cardiac arrythmia, muscle weakness, distension of the abdomen, trouble breathing

what is hyperkalemia and what are its causes

incr K; from excessive clotting, hemolytic episodes, pour off tube, diabetes, metabolic acidosis

what is metabolic acidosis

h moves in cell k comes out to try to get body back into neutrality bicarb gets used up and keeps cl

How do you treat hyperkalemia?

give insulin (drive K back into the cell)

What are the symptoms of hyperkalemia?

describe chloride

major extracellular anion get mainly from the diet

what is the chloride shift

buffering system that maintains electrical neutrality (exchanging of bicarb -out of cell- for chloride -into the cell-) ---during metabolic alkalosis

what are the two types of calcium in the body and what does calcium do

ionized/free (active) and bound (with albumin) controls muscle contration and bone development

how is calcium regulated

PTH (inv relationship; activates bone absorption, kidney reabsorption, and renal production of active vit D), vitamin D, and calcitonin (lower ca)

what are calcium levels dependent on

albumin levels

what is hypocalcemia and what causes it

low calcium caused by low PTH, lack of vit D, and low albumin

symptoms of hypocalcemia and how to correct it

tetany (muscle cramps, seizures, arrythmia); give ca or vit D

what is tetany

muscle rigidity

what is hypercalcemia and what causes it

to much calcium; from hyperparathyroidism, multiple mylenoma

what are the sumtoms of hypercalcemia

stones bones moans and groans (GI, aches, stones)

what is ionized sample and what is so special about it

free calcium that is dependent on albumin levels and needs to be collected anaerobically

describe magnesium and its main functions (where do we get it from)

intracellular cation in muscle and bone, function is cofactor for over 300 enzymes, and we mainly get it from our diet

what are the two forms of magnesium

ionized or bound (to albumin)

what do hypomagnesium cause

vasospasms, cardiac arrest, pancreatitis, pre-eclampsia (teteny- rare)

what does hypermagnesia cause

overuse of antacids (not really seen)

what doe magnesium help to kickstart

PTH

what enzymatic reaction can magnesium help with

coagulation

what is phosphate and what regulates it

major buffering system in the urine; regulators- PTH (lower P incr Ca- excretes P)

what is lactic acid and what is it a good indicator for

demines hypoxia good determinant of bacterial sepsis (because bac use O2)

what is the normal pathway of aerobic glucose metabolism and how does it change during acidosis

gluc pyruvate CoA; acidosis has no CoA and has lactose

what is anion gap

the number of cations relative to the number of anions

what is the formula for anion gap

(Na+K)-(Cl+HCO3)

what is the most common cause for change in anion gap (increased)

DKA

what is the most common cause for decrease in anion gap

hypoalbuminemia