33 results
Cerebral Salt Wasting vs SIADH - Pathophysiology 
1) Neurological event
2) Sodium loss from tubules
3) Naturiesis →
Salt Wasting vs SIADH ... - Pathophysiology ... → Increased urine ... #Pathophysiology ... #diagnosis #nephrology
Hyponatremia Differential Diagnosis Algorithm - Utilizing Uric Acid 
ADH promotes Urea/uric acid excretion along with water
Osmolarity 2) Urine ... Osmolarity 3) Urine ... Low Uric Acid → SIADH ... Diagnosis #Algorithm #nephrology
Hyponatremia Diagnosis Algorithm
UOsm ≥ POsm - Vasopressin-Dependent
 • UNa < 20 mEq/L - Appropriate (↓ EABV)
Vasopressin-Dependent • UNa ... Cirrhosis • UNa ... Inappropriate - Consider: SIADH ... algorithm #causes #nephrology
Urine Specific Gravity - Interpretation
Specific Gravity = Density of urine / Density of water
SG close to
Urine Specific Gravity ... Gravity = Density of urine ... Dehydration • SIADH ... EricsMedicalLectures/ #Urine ... #differential #nephrology
Physiologic Approach to Hypotonic Hyponatremia
The next time you have a case of hypotonic hyponatremia, give the
volume-based algorithm Urine ... restriction alone in SIADH ... or Ineffective (UNa ... Present (Uosm ≥100): SIADH ... table #sodium #nephrology
Volume Based Approach to Hyponatremia
Hypovolemic, Serum uric acid >4
 • Urine Na <20: Extra-renal losses
 •
uric acid >4 • Urine ... Extra-renal losses • Urine ... uric acid <4 • SIADH ... uric acid >4 • Urine ... #sodium #low #nephrology
Hyponatremia - Diagnostic Evaluation Algorithm

Step 1: Consider whether Posm may actually be normal or elevated
Step 2:
Check Uosm and/or Urine ... status and measure UNa ... tests Step 5: If SIADH
SIADH Treatment Options
1. Treat underlying cause of SIADH: Pain, Primary lung pathology, Post-operative phenomenon, Medications, Basically
SIADH Treatment ... 0.9% NS • If Urine ... osmolality < 538 AND UNa ... Hypotension, Increased urine ... #hyponatremia #nephrology
Management of SIADH
Treat underlying cause:
 • Causes can include pain, primary lung pathology, post-operative phenomenon, medications,
Management of SIADH ... Saline: • If Urine ... osmolality < 538 AND UNa ... SatyaPatelMD #SIADH ... #hyponatremia #nephrology
Modified Hyponatremia Algorithm
Hypertonic Hyponatremia: Hyperglycemia, Mannitol, Urologic irrigants
Hypotonic Hyponatremia: 
 • ADH ON (UOsm > 100):
- RAAS ON (UNa ... - RAAS OFF (UNa ... > 30): SIADH, Medications ... diagnosis #sodium #nephrology