Sodium

Question 1

Hyponatraemia

Answer 1

Excess loss through diuretics, adrenal insufficiency, vomiting, diarrhoea, GI suction, stroke (cerebral haemorrhage, trauma, surgery- cause cerebral salt wasting), burns, excessive sweating, tap water enemas, heart failure, cirrhosis, DKA, acute kidney disease, chronic kidney disease, addisons, diuretics, fluid replacement

Water gains that lead to hyponaetremia- renal failure, heart failure, cirrhosis liver, syndrome of inappropriate ADH, excess hypotonic IV

S&S- drop serum osmolality, muscle cramps, weakness, fatigue, anorexia, nausea/vomiting, abdo cramping, diarrhoea, cellular oedema (headache, depression, personality changes, irritability, hyperreflexia), seizures, coma

Treat- hypovolaemia- IV fluids isotonic , hypervolaemia - diuretics and hypotonic fluids

Question 2

Hypernatraemia

Answer 2

Excess sodium and excess water or excess sodium water loss

Body protects against hypernatraemia with ADH (excess sodium in ECF so kidneys then reabsorption water which diluted sodium) and thirst mechanism

Cause- diarrhoea, insensible losses, altered mental/physical state where can’t respond to thirst( brain injury), ingestion excess salt, hypertonic IV, heat stroke, near drowning in sea water, chronic kidney disease, conns disease, Cushings disease, diabetes insipidus, lithium therapy, over replacement of sodium

S&S- hyperosmolality, cerebral bleeding (brain cells shrink and pull at vessels leads to tearing and bleeds), thirst, lethargy, weakness, irritability, seizures, coma, death

Treat- IV hypotonic 0.45 saline- slowly, oral water, diuretics to flush out sodium

Question 3

Sodium 135-145

Answer 3

Mostly found in extracellular fluid

Maintains fluid levels, nerve impulses, muscle function/contraction, BP control

Controlled by renin-angiotensin (released by kidneys and if elevated K+ concentration in ECF released directly by adrenal cortex) and ANP (inhibits ability of collecting ducts to reabsorb sodium and suppress release of ADH, renin and aldosterone)-