Diagnostic and Laboratory Tests: How Nursing Students Should Interpret Results

Laboratory and diagnostic tests are tools that support clinical assessment. Nurses should understand why a test is ordered, how to prepare the patient, what to monitor, and how to recognize results that require prompt attention.

Reference Ranges

Reference ranges vary by laboratory, method, age, sex, pregnancy status, and clinical context. Always use the range reported by the laboratory rather than relying on one memorized number.

Complete Blood Count

The CBC commonly includes hemoglobin, hematocrit, red blood cells, white blood cells, and platelets. Interpret patterns alongside symptoms and trends.

Renal Function

Creatinine, urea-related measures, estimated filtration measures, urine output, and electrolytes help assess kidney function and fluid balance.

Glucose Testing

Glucose may be assessed fasting, random, after meals, or through longer-term measures such as HbA1c. Interpretation depends on clinical purpose and patient factors.

Liver-Related Tests

Common panels include transaminases, alkaline phosphatase, bilirubin, albumin, and others. Patterns are more informative than one isolated result.

Coagulation Tests

Common tests evaluate aspects of clotting and may be used when monitoring selected anticoagulant therapies or investigating bleeding and clotting disorders.

Nursing Responsibilities

Prepare the patient correctly, obtain specimens safely, label accurately, transport promptly, recognize critical-result procedures, and monitor after invasive diagnostic tests when required.