CMP Analysis

Patient Info

MaleFemale

Age

CMP Values

Glucose(mg/dL)

BUN(mg/dL)

Creatinine(mg/dL)

Sodium(mEq/L)

Potassium(mEq/L)

Chloride(mEq/L)

CO2(mEq/L)

Calcium(mg/dL)

Total Protein

Albumin(g/dL)

Bilirubin(mg/dL)

ALP

ALT(U/L)

AST(U/L)

Frequently Asked Questions

How do I calculate and use the anion gap?

Anion gap = Na - (Cl + HCO3). Normal is 8-12 mEq/L. Elevated anion gap metabolic acidosis (HAGMA) differential: MUDPILES — Methanol, Uremia, DKA, Propylene glycol, INH/Iron, Lactic acidosis, Ethylene glycol, Salicylates. Always calculate the delta-delta: delta AG / delta HCO3. Ratio >2 suggests concurrent metabolic alkalosis; ratio <1 suggests concurrent non-anion gap metabolic acidosis (NAGMA).

What is the approach to hyponatremia?

Step 1: Confirm true hyponatremia (check serum osmolality — if >295, consider pseudohyponatremia from glucose/lipids/protein). Step 2: Assess volume status — Hypovolemic (diuretics, GI losses, third-spacing), Euvolemic (SIADH most common, hypothyroidism, adrenal insufficiency), Hypervolemic (CHF, cirrhosis, nephrotic syndrome). Step 3: Check urine sodium and osmolality. SIADH: urine osm >100, urine Na >40. Correction rate: no faster than 8 mEq/L in 24 hours to avoid osmotic demyelination syndrome.

When should elevated liver enzymes trigger a workup?

Hepatocellular pattern (ALT/AST predominant): If >2x ULN, check hepatitis B/C serologies, iron studies, ANA/ASMA, and review medications/alcohol. AST:ALT ratio >2 suggests alcoholic liver disease. Cholestatic pattern (ALP/bilirubin predominant): Get right upper quadrant ultrasound to rule out biliary obstruction. If normal, check AMA (PBC), consider MRCP (PSC). Mixed pattern: Consider drug-induced liver injury. Always calculate R-value: (ALT/ULN) / (ALP/ULN) to classify the pattern.