The nurse is administering subcutaneous enoxaparin to a client following knee replacement surgery to prevent a deep vein thrombosis. Which laboratory result requires immediate action by the nurse? Reference Range: Hematocrit [42% to 52% (0.42 to 0.52 volume fraction)] Platelets [150,000 to 400,000/mm (150 to 400 x 10L) Creatinine (0.5 to 1.1 mg/dL (44 to 97 μmol/L)] Blood Urea Nitrogen (BUN) [10 to 20 mg/dl (3.6 to 7.1 mmol/L)]

A) A serum creatinine level of 1.0 mg/dL falls within the reference range (0.5 to 1.1 mg/dL) and does not indicate immediate action by the nurse. Creatinine levels within the reference range suggest normal kidney function. B) A platelet count of 100,000/mm3 (100 x 10^9/L) is below the lower limit of the reference range (150,000 to 400,000/mm3). Thrombocytopenia, or low platelet count, increases the risk of bleeding complications, especially when administering anticoagulants like enoxaparin. Therefore, a platelet count of 100,000/mm3 requires immediate action by the nurse to assess for bleeding and notify the healthcare provider. C) A hematocrit of 45% (0.45 volume fraction) falls within the reference range (42% to 52%) and does not indicate immediate action by the nurse. D) A blood urea nitrogen (BUN) level of 20 mg/dL (7.1 mmol/L) falls within the reference range (10 to 20 mg/dl) and does not indicate immediate action by the nurse.