Lecture Notes: Complete Blood Count (CBC) Elements

Introduction

• Focus on elements of the Complete Blood Count (CBC).
• Key components: Red Blood Cells (RBCs), White Blood Cells (WBCs), Hemoglobin, Hematocrit, Platelets.

Red Blood Cells (RBCs)

• Primary Function: Carry oxygen to cells for ATP production.
• Structure: Contains hemoglobin, a protein with iron elements where oxygen binds.
• Lifespan: 120 days (4 months).
• Production: Stimulated by erythropoietin, a hormone from kidneys.
• Anemia: Defined by a 10% reduction from normal RBC values.
  • Iron Deficiency Anemia: Many RBCs, less hemoglobin due to lack of iron.
  • Pernicious Anemia: Few RBCs, low vitamin B12.
• Oxygen Carrying Capacity: Low RBCs reduce capacity, leading to hypoxia.

Hemoglobin

• Role: Determines blood oxygen carrying capacity.
• Importance: Essential for energy (ATP); lack leads to symptoms like fatigue, weakness.
• Types of Anemia:
  • Iron Deficiency Anemia: Low iron content.
  • Pernicious Anemia: Low vitamin B12; affects RBCs and WBCs.

Hematocrit

• Definition: Percentage of RBCs in whole blood.
• Normal Ranges: Varies by gender.
• Indicators:
  • Low hematocrit indicates anemia.
  • High hematocrit could indicate polycythemia or chronic respiratory issues.

White Blood Cells (WBCs)

• Function: Fight off infections (bacterial, viral, parasitic).
• Types: Not detailed; focus on total WBC count.
• Increases: May indicate infection, stress, or chronic conditions.

Platelets

• Function: Important in clotting through aggregation.
• Process: Form a platelet plug at injury site, communicate with clotting factors.
• Count: Measured per cubic millimeter of blood.

Normal CBC Values

• RBCs: Males 5-6 million/μL, Females 4-5 million/μL.
• Hemoglobin: Males 14-18 g/dL, Females 12-16 g/dL.
• Hematocrit: Males 42-52%, Females 37-47%.
• Platelets: 150,000-400,000/μL.
• WBCs: 5,000-10,000/μL.

Alterations in Blood Levels

Elevated Levels

• RBC/Hemoglobin/Hematocrit: May indicate illness, chronic disease, high altitudes.
• WBCs: Infection, stress, inflammation, steroid therapy.
• Platelets: Blood disorders, cancer, infections.

Decreased Levels

• RBC/Hemoglobin/Hematocrit: Anemia (B12 deficiency), bone marrow failure, pregnancy, hemorrhage.
• WBCs: Bone marrow failure, overwhelming infection, chemo.
• Platelets: Blood diseases, chemo, infections.

Clinical Manifestations

• High RBCs: Ruddy complexion.
• High WBCs: Signs of infection.
• High Platelets: Excessive clotting.
• Low RBCs: Weakness, pallor, dyspnea.
• Low WBCs: Risk for opportunistic infections.
• Low Platelets: Prolonged bleeding.

Management

High Levels

• RBCs: Blood removal or donation may be needed.
• WBCs: Antibiotics, bone marrow suppression.
• Platelets: Anti-platelet or anticoagulation therapy.

Low Levels

• RBCs: Transfusions, fall precautions, nutrition supplements.
• WBCs: Bone marrow boosting medications, neutropenic precautions.
• Platelets: Transfusions, bleeding precautions.