What is a basic metabolic panel (BMP)?

What is a Basic Metabolic Panel (BMP)?

A basic metabolic panel (BMP) is a routine blood test that measures seven key analytes: serum sodium, potassium, chloride, bicarbonate, glucose, blood urea nitrogen (BUN), and creatinine. 1

Components and Clinical Significance

The BMP provides essential information about three major physiological systems:

Electrolyte Balance

• Sodium, potassium, and chloride reflect fluid balance, acid-base homeostasis, and cellular function 2
• These electrolytes both reflect and impact renal function 2
• Abnormalities can indicate dehydration, kidney dysfunction, or endocrine disorders 1

Kidney Function

• Blood urea nitrogen (BUN) and creatinine are the primary markers of renal function 1
• Creatinine is routinely measured as part of the BMP and serves as the initial test for evaluating glomerular filtration rate (GFR) 1
• These values are best considered together because they both reflect and impact renal function 2

Glucose Metabolism

• Glucose provides screening information for diabetes and metabolic control 1
• The BMP can identify abnormal blood glucose as part of cardiovascular risk assessment 1

Clinical Applications

Routine Screening and Monitoring

• The BMP is one of the most commonly ordered laboratory panels in clinical practice 3
• It serves as baseline testing in various clinical scenarios including preoperative evaluation 1, emergency department assessment 1, and routine health monitoring 1
• In hip fracture patients, BMP values are routinely checked to clear patients for surgery 1

Disease Diagnosis and Management

• Resistant hypertension evaluation: A basic metabolic profile (serum sodium, potassium, chloride, bicarbonate, glucose, BUN, and creatinine) is recommended as part of the biochemical evaluation 1
• Obesity management: A comprehensive metabolic panel (which includes all BMP components plus additional liver function tests) is recommended for basic laboratory evaluation 1
• Post-procedural monitoring: Daily BMP monitoring is used after certain procedures like CAR T-cell therapy to screen for tumor lysis syndrome 1

Predictive Value

• A BMP-derived risk score has demonstrated superior predictive ability for 30-day, 1-year, and 5-year mortality when combined into a total score adjusted for age and sex 4
• The predictive ability was confirmed to be independent of traditional risk scores like the Framingham Risk Score 4

Important Clinical Considerations

When BMP Testing is Most Valuable

• Patients with chronic kidney disease: These patients have increased risk for abnormal creatinine and potassium requiring medical intervention 5
• Patients with diabetes: These patients have significantly increased risk for abnormal glucose values requiring intervention 5
• Patients with abnormal preoperative values: Abnormal baseline laboratory values are strongly associated with need for medical treatment postoperatively 5

Avoiding Unnecessary Testing

• Routine daily BMP testing in patients without major medical comorbidities and with normal preoperative values often does not contribute to actionable information 5
• In one study, patients who did not require medical intervention averaged 2.8 BMP tests, equating to $472,372.56 in total hospital charges for unnecessary testing 5
• Implementation of automated panel ordering can dramatically increase testing volumes without changing the rate of clinically significant diagnoses 3

Relationship to Comprehensive Metabolic Panel

• The comprehensive metabolic panel (CMP) includes all BMP components plus additional tests (total protein, albumin, total bilirubin, alkaline phosphatase, AST, and ALT) 1
• The BMP is preferred when focused assessment of electrolytes, kidney function, and glucose is needed without liver function evaluation 1