CC Jan 2017 Hyponatremia

echoecho's version from 2017-03-07 07:02


Question Answer
Define Hyponatremia?Serum sodium < 135 mEq/L
It is the most common electrolyte abnormality and is found in up to ___% of hospitalized patients?30%
Two categories of Hyponatremia related to time limits?1) acutely (< 48 hours). 2) chronic (> 48 hours)
Depending on the serum sodium level, symptoms range from?Mild, nonspecific fatigue to seizure, coma and death
List the MEq/L levels for Hyponatremia to be considered mild, moderate or severe?1) mild = 130-135 mEQ/L. 2) moderate = 125-129 mEq/L. 3) severe/profound = < 125 mEq/L'
If the Hyponatremia is severe/profound, what are the symptoms related to severe Hyponatremia?acute gastrointestinal fluid loses, somnolence, cardio respiratory distress
Seizures and coma may develop with rapid reductions in sodium levels, even if they do not reach _____ levels?profound
The above complications develop as a result of what two reasons?1) cerebral edema 2) increased intracranial pressure
The evaluation of a patient with asymptomatic or mild symptomatic Hyponatremia starts with measurement of what?serum osmolality
If the serum osmolality is normal (280-285 mOsm/kg), the patient has _____ _____?isotonic Hyponatremia
The above is also known as what?pseudohhyponatremia
*** What is the cause of pseudohhyponatremia?because electrolyte testing utilizing indirect ion selective electrodes may falsely calculate a low serum sodium.
*** List the conditions that cause pseudohhyponatremia?1) marked hyperlipidemia 2) elevated serum proteins
In the above situation, the water content of serum (usually ____%) is relatively reduced due to increased serum lipid or protein?93%
Are cirrhosis, hypothyroidism and supplemental vit D associated with pseudohyponatremia?no
What type of testing eliminates the possibility of pseudohyponatremia and is now available in most large labs and bedside electrolyte testing units?direct ion selective electrode testing
What does the patient have if the serum osmolality is high (> 285 mOsm/kg H20)?hypertonic Hyponatremia
List the conditions that cause hypertonic Hyponatremia?1) hyperglycemia. 2) recent mannitol or sorbitol use 3) recent administration of radio contrast
Some authors use the term pseudohyponatremia for the low serum seen in diabetic ketoacidosis, why does this term not really apply?because in this case while the serum is low, it is the result of movement of water from cells into the blood because of the increased osmolality caused by the hyperglycemia, so the term does not really apply. The hyperglycemia results in dilutional Hyponatremia
Most commonly, the serum osmolality is low (<280 mOsm/ kg H20), and this is called what?hypotonic Hyponatremia
In hypotonic Hyponatremia, it is vital to asses what?patient's fluid status (vital signs with orthostatic BP readings), skin turn or, jugular venous pressure, mucous membranes, peripheral edema as well as Uric and BUN levels.
List 3 categories of hypotonic Hyponatremia?1) hypocalcemic. 2) euvolemic 3) hypervolemic
In the category hypovolemic hypotonic hyponatremia, hyponatremia with low ______ volume results from both ____ and ____ loss and may be associated with what 2 conditions?1) extra cellular. 2) sodium 3) water 4) (a) excessive sweating or gastrointestinal losses, leading to a urinary sodium of < 20 mEQ/L OR b) mineralocorticoid deficiency or diuretic use, where the urinary sodium will be > 20 mEq/L
In the category of euvolemic hypovolemic Hyponatremia, there is Hyponatremia with normal _______ volume resulting from what two conditions?(1) SIADH (syndrome of inappropriate antidiuretic hormone secretion where the urine osmolality will be > 100 mOsm/kg or 2) intake of water in excess of sodium intake where the urine osmolality will be < 100 mOsm/kg H20
List the causes of SIADH?1) medications like TCA, SSRIs, carbamazepine (Tegretol) and opiates
What is the happens as a resultofintake of water in excess of sodium intake where the urine osmolality has will be < 100 mOsm/kg?total body water is INCREASED but is distributed normally between theintracellular and extra cellular spaces, resulting in "dilutional Hyponatremia"
In the category of hypervolemic hypovolemic Hyponatremia, Hyponatremia with increased _______ volume that may result in what 2 conditions?1) CHF, nephrons is, hhypoalbuminemia and cirrhosis in which the urinary sodium is < 20 mEq/L or (2) renal failure wher the urinary sodium is > 20 mEq/L
Management of Hyponatremia is based on symptoms at the time of ______?presentation
*** What is the treatment in the case of life-threatening Hyponatremia, regardless of etiology?1) IV administration of 150 cc of 3% hypertonic saline over 20 minutes. 2) check serum sodium 20 minutes after infusion with the goal of increasing the serum sodium by 5 mEq/l and controlling the patient symptoms. 3) a second bonus may be required if serum sodium or patient response is no adequate.
Once the patient is stabilized, an infusion of what should be instituted at the lowest possible rate until the underlying etiology can be treated?0.9% NaCl
Serum sodium level should NOT be increased by more than ____ mEq/L or to a level above ____ mEq/L in the first 24 hours, why?10; 130; to prevent osmotic demyelination syndrome which may rarely occur as a result of rapid correction of sodium in chronic Hyponatremia
For patients who are asymptomatic or only mildly symptomatic, what is the treatment?it depends on the underlying etiology as determined by the testing noted above.
What is the primary intervention?managing any underlying disorder causing the Hyponatremia.
List the general measures for treating hypovolemic Hyponatremia?isotonic saline
List the general measures for treating euvolemic Hyponatremia?fluid restriction
List the general measures for treating hypervolemic Hyponatremia?both fluid and sodium restriction and in addition, diuresis is used for CHF, cirrhosis, nephrons is or hypoalbuminemia patients
*** Historically, mild chronic Hyponatremia has been associated with low clinical risk. However, more recent studies indicate that chronic Hyponatremia is associated with an increased risk of ______ and ____ related to falls?osteoporosis; fracture
*** With 1/3 of the total body sodium stored in the _____, it is thought that chronic Hyponatremia leads to sodium reabsorption from the bone, contributing to ______?bones; osteoporosis
*** Chronic Hyponatremia may also result in what other symptoms?poor concentration; cognitive decline; gait instability; increased fall rates
*** Does chronic Hyponatremia lead directly have to hypothyroidism, cholelithiasis, dementia or diabetes?no
*** SUMMARY = Hyponatremia is the most common electrolyte abnormality, and may have trivial or life-threatening effects depending on what four factors?1) acuity. 2) severity 3) cause and underlying health status of affected patient
*** SUMMARY = Management of symptomatic Hyponatremia includes slow IV ______ replacement to avoid what 2 sequelae? sodium; cerebral edema and increased intracranial pressure
*** SUMMARY = Measurement to sodium levels in presumed Hyponatremia should be coupled with measurement of _____ _______ to r/o pseudohyponatremia?serum osmolality
*** SUMMARY = What is pseudohyponatremia?a spurious reduction in serum sodium values caused by INDIRECT laboratory analysis?