Category: Internal Medicine / Clinical Case Studies
Tags: Electrolyte Disorders, Internal Medicine, Clinical Reasoning, PANCE Case Study
SEO Focus Keyword: PANCE electrolyte disorders
Excerpt (for cards):
A 67-year-old woman with confusion and nausea reveals one of the most tested PANCE electrolyte challenges — hyponatremia. Learn how to diagnose and correct safely.
Full Article:
A 67-year-old woman presents with lethargy, confusion, and nausea. Labs show Na⁺ 118 mEq/L (normal 135–145), K⁺ 3.9 mEq/L, serum osmolality 260 mOsm/kg. Urine osmolality is elevated.
1. Identify the Type
Step one: Is it hypotonic, isotonic, or hypertonic? A low serum osmolality confirms true hypotonic hyponatremia.
2. Assess Volume Status
Physical exam distinguishes between hypovolemic, euvolemic, and hypervolemic states — a core PANCE diagnostic skill. This patient’s absence of edema and normal skin turgor suggests euvolemic hyponatremia, often due to SIADH.
3. Confirm Etiology
SIADH may result from medications (SSRIs, carbamazepine), pulmonary disease, or malignancy. Further workup includes TSH, cortisol, and chest imaging.
4. Correct Carefully
Rapid correction risks osmotic demyelination. Limit sodium rise to ≤8 mEq/L in 24 hours. Use fluid restriction, hypertonic saline if symptomatic, and loop diuretics for select cases.
Takeaway:
Electrolyte reasoning is pattern recognition in disguise. The BEYOND PANCE approach transforms lab data into logic — because every mEq tells a story.