NURS 215 FINAL: electrolytes part 1

what electrolytes are outside the cells?

sodium and chloride

what electrolytes are inside the cells?

potassium and phosphate

what are the main functions of sodium?

controls fluid balance, nerve function, and muscle contraction. maintains proper cell and organ function

what is the normal sodium range?

135-145

what two conditions primarily activate the renin-angiotensin-aldosterone system?

when blood pressure or sodium is low

what substance is released by the kidneys to start the RAAS pathway?

renin

what are the two main actions of angiotensin II that lead to an increase in blood pressure?

it constricts blood vessels and it signals the adrenal glands to release aldosterone

what are the causes of hyponatremia?

fluid loss, excess water intake, impaired water excretion, hormonal imbalances

what is the pathophysiology of hyponatremia?

low blood sodium leads to water moving into the cells which leads to cells swelling

what are the main symptoms of hyponatremia and the worst outcomes?

changes in mental status, seizures, decreased level of consicousness. worst outcomes are brain swelling and increased pressure in the brain

what are the causes of hypernatremia?

water loss, inadequate water intake, excess water loss, renal water loss

what is the pathophysiology of hypernatremia?

high blood sodium leads to water moving out of cells which leads to cells shrinking. in rapid rise, brain cells shrink quickly

what are the main symptoms of hypernatremia and the worst outcomes?

intense thirst, muscle twitching, dry mucus membranes, low bp and tachycardia. worst outcomes are high pitched cry in infants and subtle symptoms in elderly until sodium is very high

what is the normal potassium range?

3.5 to 5.3

what does the sodium potassium pump do?

moves potassium into cells and sodium out

what do catecholamines do with potassium?

they stimulate potassium uptake into cells during stress or exercise. they also activate sodium potassium pump

what are the causes of hypokalemia?

diuretics, gi losses, excessive sweating, shift of potassium into cells, starvation

what is the pathophysiology of hypokalemia?

low potassium makes cells less excitable. it makes it harder for nerves and muscles to send signals and contract. especially affects the heart by causing arrhythmias

what are the main symptoms of hypokalemia and the severe ones?

muscle weakness or cramps, constipation, arrhythmias, muscle paralysis, respiratory weakness, cardiac arrest

what are the main causes of hyperkalemia?

most common is impaired kidney function. also medications, metabolic acidosis, insulin deficiency, excessive intake

what is the pathophysiology of hyperkalemia?

kidneys excrete extra potassium. high potassium makes resting membrane potential less negative

what are the main symptoms of hyperkalemia and the serious ones?

muscle weakness or paralysis, paresthesias, nausea, palpitations, life threatening arrhythmias