Complete Blood Count (CBC) Normal Values and Nursing Considerations

Complete Blood Count (CBC)

  • It is a basic screening test and is one of the most frequently ordered laboratory procedures.
  • The findings in the CBC give valuable diagnostic information about the hematologic and other body systems, prognosis, response to treatment, and recovery.
  • The CBC consists of a series of tests that determine the number, variety, percentage, concentration and quality of blood cells.


  1. White blood cell count (WBC): presence of infection
  2. Differential white blood cell count: specific patterns of WBC
  3. Red blood cell count (RBC): carries oxygen and carbon dioxide from lungs to tissue and vice versa
  4. Hematocrit (Hct): measures RBC mass
  5. Hemoglobin (Hgb): main component of RBC
  6. Red blood cell indices: calculated values of size and Hgb content of RBCs, important in anemia evaluation
  7. Platelet count: necessary for clotting and control of bleeding
  8. Red blood cell distribution width (RDW): indicates degree variability and abnormal cell size
  9. Mean platelet volume (MPV): index of platelet production

Normal Values in Adults

WBC: 5.0 – 10.0 x 103/mm3

RBC: 4.0 – 5.5 x 106/mm3

Hgb: 12.0 – 17.4 g/dL

Hct: 36 – 52%

Platelet: 140 – 400 x 103/mm3

RDW: 11.5 – 14.5%

MPV: 7.4 – 10.4 fL

Nursing Considerations

  1. Explain test procedure. Explain that slight discomfort may be felt when the skin is punctured.
  2. Encourage to avoid stress if possible because altered physiologic status influences and changes normal hematologic values.
  3. Explain that fasting is not necessary. However, fatty meals may alter some test results as a result of lipidemia.
  4. Apply manual pressure and dressings over puncture site on removal of dinner.
  5. Monitor the puncture site for oozing or hematoma formation.
  6. Instruct to resume normal activities and diet.

Daisy Jane Antipuesto RN MN

Currently a Nursing Local Board Examination Reviewer. Subjects handled are Pediatric, Obstetric and Psychiatric Nursing. Previous work experiences include: Clinical instructor/lecturer, clinical coordinator (Level II), caregiver instructor/lecturer, NC2 examination reviewer and staff/clinic nurse. Areas of specialization: Emergency room, Orthopedic Ward and Delivery Room. Also an IELTS passer.

What Do You Think?