Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of hyponatremia/hypernatremia
causes of hypernatremia heart failure extracellular sodium and water
are increased extracellular sodium and water are normal extracellular sodium and water are decreased hypo-/hyer-Natremia sodium and water homeostasis
imbalances hyponatremia intra-cellular sodium is decreased extra-renal cause
urine sodium less than 20 mmol/L vomiting
pancreatitis renal cause
urine sodium more than 20 mmol/L 1. osmotic diuresis : (hyperglycemia, severe uraemia)
diuretics : thiazide, as a loop diureticit decreases tonicity of medullary interstitium and impair urine concentrating ability
2 .adrenocortical insufficency :
3. tubulo-interstitial renal disease :
4. unliateral renal artery stenosis :
5. recovery phase of acute tubular necrosis : hypovolemia abonrmal ADH release vagal neuropathy failure of inhibition of ADH release deficiency of hypothyroidism severe potassium depletion a. ACTH
b. glucocorticoids ( addison) increase sensitivity to ADH chloropropamide tolbutamide type 2 diabetes medication
stimulate insulin in B-cells and
increase sensitivity for peripheral insulin ADH-like substances oxytosin
desmopressin osmotic ADH release stimulators glucose
chronic alcohol abuse
sickl-cell syndrome leakage of intracellular
ions major psychiatric illness anti-depressant therapy psychogenic polydepsia SIADH euvolemia hypervolemia decrease CO and EAV liver failure splanchic vasodilation and ascitis & decrease EAV oligouric renal failur cant execrete water low albumin pathophysilogy increase salt loss & excess of water loss
ADH secretion is inhibited by the hypothalamic osmoreceptors which makes volume receptors to induce thirst and ADH.
with extrarenal loss & normal kidney the urinary secretion of sodium falls in
response to volume depletion so water excretion is decreased = concentrated urine.
in salt wasting kidney disease, there is no renal compensation only thirst occurs water excess although kidney excretes well ( dilutional hyponatremia).
body content of Na is normal but plasma osmolality is low. most common iatrogenic cause:
overinfusion of 5% glucose to posoperative patients & ADH increase due to stress.
marathon runners , they drink alot.
postmenopausal women have risk of developing hyponatremic encephalopathy prophylaxis to hyponatremia in surgery = use isotonic saline GFR reduction and huge sodium and chloride re-absorption in proximal tubules. so chloride is not available anymore in the loop of Henle so reduced ability to genrate free water.
this phenomena is increased by
thiasides ( distally) hypernatremia very less common in almost all situations we have water deficit.
it is always associated with increased plasma osmolality ( stimulate thirst).
none of causes can cause hypernatremia unless thirst sensation is abnormal ( think of elderly people).
a. ADH deficiency diabetes insipidus
insensitivity to ADH( nephrogenic diabetes insipidus):
-acute tubular necrosis osmotic diuresis:
- total parenteral nutrition (hyperosmolar).
- hyperglycemic state DEFICIENT WATER INTAKE PLUS THANK YOU
under suprevision of
Dr. Nada ghrayeb