Alterations in Oxygen Transport

Erythrocytes are

RBCs

Leukocytes are

WBCs

Normal erythrocyte count

4.2-6.2 million cells/mm³

Normal erythrocyte lifespan

80-120 days

Normal leukocyte count

5000-10000/mm³

What might a leukocyte count >10000 indicate

Infection

Normal platelet count

150,000-400,000/mm³

What do platelets do?

Assist in clot formation

What might a platelet count <150,000 indicate?

Bleeding risk

What might a platelet count >400,000 indicate?

Clot risk

Plasma is what % of blood

55%

Blood cells are what % of blood

45%

Blood cells include

Erythrocytes, leukocytes, and platelets

Where are plasma proteins formed?

Liver

What might dehydration do to plasma?

Decrease plasma

What is hematopoiesis

Creation of blood cells

Where does hematopoiesis occur?

The bone marrow

What is erythropoiesis?

Production of RBCs

What does the kidney secrete in response to hypoxia?

Erythropoietin

What does erythropoietin do?

Stimulates the bone marrow to produce more RBCs

What is a reticulocyte?

An immature RBC

What is hemoglobin?

Oxygen-carrying protein in mature RBCs

Where is hemoglobin formed?

Reticulocytes (immature RBC)

What percentage of O2 is bound to Hgb?

97%

What percentage of O2 is dissolved in plasma?

3%

What is a normal saturation of venous blood?

60-80%

What is the normal partial pressure of O2 in arterial blood?

80-100 mmHg

What is the normal partial pressure of O2 in venous blood?

35-40 mmHg

What affects the affinity of Hgb for O2?

Temperature, acid-base balance, carbon dioxide, other factors

What is anemia

A deficit of RBCs

What is polycythemia

Excess RBCs

What is relative anemia

There is a normal RBC count but plasma volume has increased

What is absolute anemia

A decrease in the number of RBCs

Mild anemia clinical manifestations

Usually no clinical symptoms

Mild-moderate anemia clinical manifestations

Fatigue, generalized weakness, tachycardia

Moderate-severe anemia clinical manifestations

Tachypnea, tachycardia, headache, lightheadedness, BP drops with position changes, tinnitus

What does MCV stand for

Mean corpuscular volume

What is mean corpuscular volume

Average size of RBCs

What does MCH stand for

Mean corpuscular hemoglobin

What is mean corpuscular hemoglobin

Average amount of hemoglobin per RBC

What does MCHC stand for

Mean corpuscular hemoglobin concentration

What is mean corpuscular hemoglobin concentration

Average amount of Hgb per unit of volume

How long does it take for a reticulocyte to mature?

1-2 days

What does an elevated reticulocyte count indicate?

Trauma & blood loss

Do reticulocytes carry O2?

No

Anemia (general) clinical manifestations

Reduced O2 carrying capacity, tissue hypoxia, compensatory mechanisms activated - increased pulmonary function, increased cardiac function, decreased affinity of Hgb in tissues, increased erythropoietin activity, selective tissue perfusion provides shunting to vital organs

Iron deficiency anemia pathophysiology

Most common nutritional deficiency; insufficient iron for Hgb synthesis

Iron deficiency anemia clinical manifestations

Pica, koilonychias (spoon-shaped nail), blue sclera

Iron deficiency anemia diagnosis

CBC - hypochromic, microcytic RBCs, low MCV, MCH, and MCHC; Serum iron levels - low serum ferritin levels, total iron binding capacity increased

Iron deficiency anemia treatment

Administer iron, treat underlying cause

Sickle cell anemia pathophysiology

Autosomal recessive; Hemoglobin S (HbS); disease vs. trait; HbS have difficulty moving through blood vessels, become sticky, and morph into a characteristic sickle, clogging blood vessels

Sickle cell anemia clinical manifestations

Pain, hypoxia, jaundice

Sickle cell anemia diagnosis

Prenatal screening and early diagnosis key

Sickle cell anemia treatment

Gene and stem cell therapy in experimental stage