15 results
Physiologic Approach to Hypotonic Hyponatremia
The next time you have a case of hypotonic hyponatremia, give the
time you have a case ... normal volume-based algorithm ... Urine Na+K / serum ... , Renal Sodium loss ... can be high or low
Hyponatremia - Differential Algorithm
Isotonic Hyponatremia: Hyperlipidemia, Hyperproteinemia, Recent TURP
Hypotonic Hyponatremia: 
 • Hypovolemia: Diuretics/Nephropathies, Vomiting, Diarrhea,
: Diuretics/Nephropathies ... • Euvolemia: SIADH ... #diagnosis #causes ... #nephrology #sodium ... #low
Volume Based Approach to Hyponatremia
Hypovolemic, Serum uric acid >4
 • Urine Na <20: Extra-renal losses
 •
Hypovolemic, Serum ... uric acid <4 • SIADH ... Hypothyroidism, Low ... #algorithm #diagnosis ... #sodium #low #nephrology
Hypernatremia Diagnosis and Workup

Step 1 . Repeat the sodium concentration.
Step 2.  Check plasma osmolality.
NORMAL PLASMA
Repeat the sodium ... HYPOVOLEMIC • ... volume loss - diuretics ... EUVOLEMIC • SIADH ... HYPERVOLEMIC • CHF
Modified Hyponatremia Algorithm
Hypertonic Hyponatremia: Hyperglycemia, Mannitol, Urologic irrigants
Hypotonic Hyponatremia: 
 • ADH ON (UOsm > 100):
ON (UNa < 30): Hypovolemia ... OFF (UNa > 30): SIADH ... , Medications (diuretics ... Primary polydipsia, Low ... #sodium #nephrology
Hypernatremia - Differential Diagnosis Workup Algorithm

1) Check Urine Osmolality:
 > 600 mOsm/kg - Implies extrarenal mechanism
Diagnosis Workup Algorithm ... 1) Check Urine ... : • Hypovolemic ... • Euvolemic (Low ... #nephrology #sodium
Hyponatremia - Differential Diagnosis Algorithm
Hypovolemic - Give volume
Hypervolemic (Edematous) - Look for and treat underlying cause
Hypovolemic - Give ... treat underlying cause ... (CHF, cirrhosis ... , SSRIs) - SIADH ... diagnosis #nephrology #sodium
Causes of Hyponatremia - Differential Diagnosis Algorithm
Syndrome of Inappropriate ADH - Euvolemic; no physiologic stimulus to
Causes of Hyponatremia ... Malignancy True hypovolemia ... especially thiazide diuretics ... Reduced GFR, AKI/CRF ... Hypo-osmolar urine
Causes of Hyponatremia - Differential Diagnosis Algorithm
Syndrome of Inappropriate ADH - Euvolemic; no physiologic stimulus to
Causes of Hyponatremia ... Malignancy True hypovolemia ... especially thiazide diuretics ... Reduced GFR, AKI/CRF ... Hypo-osmolar urine
Causes of Hypernatremia - Differential Diagnosis Algorithm
Hypernatremia - Excess free water loss, Serum Sodium >145 mmol/L
High
Causes of Hypernatremia ... water loss, Serum Sodium ... administration • Osmotic diuresis ... mannitol, glucosuria Low ... #Causes