Hematology Physiology Overview

Definition: Hematology physiology studies the functions and properties of blood and its components.

Plasma
- Liquid portion, approximately 55% of blood volume.
- Contains water, electrolytes, proteins, hormones, and waste products.
Formed Elements
- Red Blood Cells (Erythrocytes)
  - Function: Transport oxygen (O2) and carbon dioxide (CO2).
  - Contain hemoglobin for oxygen binding.
  - Lifespan: ~120 days.
- White Blood Cells (Leukocytes)
  - Function: Immune response.
  - Types: Neutrophils, lymphocytes, monocytes, eosinophils, basophils.
- Platelets (Thrombocytes)
  - Function: Blood clotting and hemostasis.
  - Lifespan: 5-10 days.

Transportation
- Oxygen from lungs to tissues.
- Nutrients from the digestive tract to cells.
- Hormones from endocrine glands to target organs.
- Waste products to excretory organs.
Regulation
- Maintains body temperature through heat distribution.
- Regulates pH levels and fluid balance.
Protection
- Immune defense against pathogens.
- Clot formation to prevent blood loss.

Definition: Process of blood cell formation.
Location: Primarily occurs in bone marrow.
Types of cells produced:
- Myeloid lineage (e.g., red blood cells, platelets).
- Lymphoid lineage (e.g., lymphocytes).

Normal Blood Volume:
- Approximately 5-6 liters in adults.
Hematocrit:
- Proportion of blood volume occupied by red blood cells.
- Normal range: 38% to 52% for men, 34% to 46% for women.
Blood Viscosity:
- Affected by the number of red blood cells and plasma proteins.

Definition: Process to stop bleeding.
Stages:
1. Vascular Spasm: Immediate constriction of blood vessels.
2. Platelet Plug Formation: Platelets adhere to the injury site and aggregate.
3. Coagulation: Formation of a stable fibrin clot through a cascade of reactions.

Anemia: Decreased red blood cell count or hemoglobin.
Leukemia: Cancer of blood-forming tissues, excessive white blood cell production.
Thrombocytopenia: Low platelet count, increased bleeding risk.
Hemophilia: Genetic disorder affecting blood clotting factors.

Hematology physiology is essential for understanding blood functions, the formation of blood cells, and the body's response to injury and disease.

Plasma
- Comprises about 55% of blood volume, consisting of water, electrolytes, proteins, hormones, and waste products.
Formed Elements
- Red Blood Cells (Erythrocytes)
  - Transport oxygen (O2) and carbon dioxide (CO2); contain hemoglobin for oxygen binding; average lifespan of roughly 120 days.
- White Blood Cells (Leukocytes)
  - Crucial for immune responses; includes five types: neutrophils, lymphocytes, monocytes, eosinophils, basophils.
- Platelets (Thrombocytes)
  - Involved in blood clotting and hemostasis; have a lifespan of 5-10 days.

Transportation
- Carries oxygen from lungs to tissues, nutrients from the digestive system to cells, hormones from glands to organs, and waste products to excretory organs.
Regulation
- Helps maintain body temperature, regulates pH levels, and ensures fluid balance.
Protection
- Provides immune defense against pathogens; facilitates clot formation to minimize blood loss.

Refers to the formation of blood cells, primarily occurring in the bone marrow.
Produces two main lineages of cells:
- Myeloid lineage includes red blood cells and platelets.
- Lymphoid lineage produces lymphocytes.

Normal Blood Volume
- Typically around 5-6 liters in adults.
Hematocrit
- Measures the percentage of blood volume occupied by red blood cells; normal levels are 38% to 52% for men and 34% to 46% for women.
Blood Viscosity
- Influenced by the number of red blood cells and plasma proteins.

Defined as the process to stop bleeding, comprising three stages:
- Vascular Spasm: Immediate constriction of blood vessels.
- Platelet Plug Formation: Platelets adhere to injury sites and aggregate.
- Coagulation: Formation of a stable fibrin clot through a cascade of biochemical reactions.

Anemia: Characterized by decreased red blood cell count or hemoglobin levels.
Leukemia: A cancer affecting blood-forming tissues, leading to excessive production of white blood cells.
Thrombocytopenia: A condition marked by a low platelet count, resulting in an increased risk of bleeding.
Hemophilia: A genetic disorder that impairs blood's ability to clot due to deficiencies in clotting factors.