17 results
Hypernatremia Diagnosis and Workup

Step 1 . Repeat the sodium concentration.
Step 2.  Check plasma osmolality.
NORMAL PLASMA
1 . ... Repeat the sodium ... Step 2. ... HYPERVOLEMIC • CHF ... #Algorithm #Nephrology
Cerebral Salt Wasting vs SIADH - Pathophysiology 
1) Neurological event
2) Sodium loss from tubules
3) Naturiesis →
1) Neurological ... event 2) Sodium ... → Increased urine ... Pathophysiology #diagnosis #nephrology ... #hyponatremia #
Volume Based Approach to Hyponatremia
Hypovolemic, Serum uric acid >4
 • Urine Na <20: Extra-renal losses
 •
Renal losses, Cerebral ... uric acid <4 • SIADH ... deficiency, Primary polydipsia ... #algorithm #diagnosis ... #sodium #low #nephrology
Hyponatremia Differential Diagnosis Algorithm - Utilizing Uric Acid 
ADH promotes Urea/uric acid excretion along with water
water retention 1) ... Serum Osmolarity 2) ... 3) Urine Sodium ... Low Uric Acid → SIADH ... #nephrology #sodium
Modified Hyponatremia Algorithm
Hypertonic Hyponatremia: Hyperglycemia, Mannitol, Urologic irrigants
Hypotonic Hyponatremia: 
 • ADH ON (UOsm > 100):
Algorithm Hypertonic ... OFF (UNa > 30): SIADH ... Reset osmostat, Cerebral ... 100): Primary polydipsia ... #sodium #nephrology
Hyponatremia - Differential Diagnosis Algorithm
Hypovolemic - Give volume
Hypervolemic (Edematous) - Look for and treat underlying cause
underlying cause (CHF ... - Primary Polydipsia ... , SSRIs) - SIADH ... #diagnosis #nephrology ... #sodium
Physiologic Approach to Hypotonic Hyponatremia
The next time you have a case of hypotonic hyponatremia, give the
normal volume-based algorithm ... Urine Na+K / serum ... Na >1 is predictive ... Insufficiency, Cerebral ... #nephrology
Hyponatremia - Diagnostic Evaluation Algorithm

Step 1: Consider whether Posm may actually be normal or elevated
Step 2:
Step 1: Consider ... elevated Step 2: ... Check Uosm and/or Urine ... tests Step 5: If SIADH ... #Diagnosis #Workup
Hypernatremia - Differential Diagnosis Workup Algorithm

1) Check Urine Osmolality:
 > 600 mOsm/kg - Implies extrarenal mechanism
Algorithm 1) ... Check Urine Osmolality ... renal mechanism 2) ... #Algorithm #nephrology ... #sodium
Hypernatremia Differential Diagnosis Algorithm - Diabetes Insipidus Workup

Step #1 - Consider the history
Step #2 - Assess
Diagnosis Algorithm ... Diabetes Insipidus Workup ... Step #1 - Consider ... history Step #2 ... #Sodium #nephrology