What labs should be ordered today?

Laboratory Tests to Order Today

Based on current guidelines, a comprehensive laboratory panel should be ordered today, including complete blood count (CBC), comprehensive metabolic panel (CMP), C-reactive protein (CRP), and thyroid function tests. 1

Core Laboratory Tests

Baseline Laboratory Assessments

• Complete blood count (CBC) with differential - essential for evaluating for anemia, infection, and platelet abnormalities 1
• Comprehensive metabolic panel including:
  • Electrolytes (sodium, potassium, chloride, bicarbonate)
  • Renal function (BUN, creatinine)
  • Liver function tests (ALT, AST, alkaline phosphatase, bilirubin)
  • Glucose, calcium, albumin 1
• C-reactive protein (CRP) - important inflammatory marker 1
• Urea and electrolytes - critical for monitoring fluid and electrolyte balance 1

Additional Important Tests

• Thyroid-stimulating hormone (TSH) - recommended as part of baseline evaluation 1
• Vitamin B12 levels - important for neurological and hematological assessment 1
• Homocysteine level - recommended in several guidelines for comprehensive evaluation 1

Disease-Specific Considerations

For Patients with Inflammatory Bowel Disease

• If managing acute severe colitis, daily monitoring should include:
  • Complete blood count
  • Urea and electrolytes
  • CRP 1

For Patients on Medication Monitoring

• For patients on digoxin:
  • Serum electrolytes and renal function should be assessed periodically 2
  • Serum digoxin concentration may be needed (drawn 6-8 hours after last dose) 2

For Patients with Suspected Cognitive Impairment

• Cognitive lab panel should include:
  • CBC with differential
  • Complete metabolic panel with electrolytes, glucose, calcium, magnesium
  • TSH, vitamin B12, homocysteine
  • CRP and erythrocyte sedimentation rate (ESR) 1

Avoiding Unnecessary Testing

• Laboratory tests should not be ordered at regular intervals (such as daily) but rather in response to specific clinical questions 1
• Limiting unnecessary testing can reduce iatrogenic anemia, costs, and unnecessary follow-up of incidental findings 1, 3
• Consider the patient's clinical condition when ordering tests - not all patients require comprehensive panels 4

Important Considerations

• Timing of laboratory tests is important, particularly for medication monitoring (e.g., digoxin levels should be drawn at trough, just before next dose) 2
• Results should be interpreted in the context of the patient's clinical condition and previous results 1
• For patients with renal impairment, more careful monitoring may be required, especially when on medications affected by renal function 2

Common Pitfalls to Avoid

• Ordering daily routine labs without specific indications can lead to iatrogenic anemia and unnecessary costs 1, 3
• Failing to consider drug-laboratory interactions when interpreting results 2
• Not accounting for the patient's renal function when interpreting certain laboratory values 2
• Missing important electrolyte abnormalities that could affect medication efficacy and safety 2

Remember that laboratory testing should be guided by the clinical context and should be interpreted as part of the overall clinical picture, not in isolation 1.