Hyponatraemia Flashcards
symptoms of hyponatraemia
increased skin turgor
tachycardia
hypotension
red cracked tongue
confusion
seizures
what % of our bodies are water
60% men
55% women
what are the three compartments of fluid in the body and how much is found in each
intracellular - 30L
interstitial - 9L
vascular - 3L
where is sodium principally found
extracellular compartments - interstitial and vascular spaces
what forces are involved in water movement out of the cell
internal hydrostatic pressure - pushes
external osmotic pressure - pulls
what forces are involved in water movement into the cell
external hydrostatic pressure - pushes
internal osmotic pressure - pulls
is water movement passive or active
passive (follows Na+)
is Na+ movement passive or active
active
how does our body respond to an alteration in tonicity
it moves water to dilute the high tonicity
volume deplete is aka
hypovolaemic
volume overloaded is aka
hypervolaemic
what are the three forms of hyponatraemia
normovolaemic
hypovolaemic
hypervolaemic
disease states which cause fluid loss
haemorrhage
vomiting
diarhhoeas
burns
diuretic states (e.g. hypercalcaeimia, diabetes mellitus)
sequestration
what is sequestration and give an example
when one of the interstitial spaces becomes inflamed and collects up to 4L of fluid
this dehydrates the rest of the body
e.g. pneumonia
iatrogenic causes of fluid loss
diuretics
stomas/fistulae
gastric aspiration
disease states which cause fluid gain
heart failure
liver failure
renal failure
hypothyroidism
psychogenic polydipsia
ADH excess
iatrogenic causes of fluid gain
IV fluids
supplemental nutrition
what changes in Na+ and water can lead to hyponatraemia
water gain
water gain > Na+ gain
Na+ loss > water loss
Na+ loss and water gain
what would be the volume state of someone who is hyponatraemic due to water gain
normovolaemic or mildly hypervolaemic
what would be the volume state of someone who is hyponatraemic due to Na+ and water gain
hypervolaemia and interstitial oedema
what would be the volume state of someone who is hyponatraemic due to Na and water loss
hypovolaemia
causes of normovolaemic/hypervolaemic hyponatraemia
SIADH
hypothyroidism
iatrogenic
causes of hypervolaemic hyponatraemia
heart failure
liver failure
nephrotic syndrome
treatment of hypervolaemic hyponatraemia
rapid salt rich fluid administration
