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EQA
Unit V Medical Surgical Nursing Care
oxygen content of the blood. Old red blood cells are trapped by
the liver where they are destroyed, though the iron contained in
the destroyed red blood cell is retained and used in the formation
of new red blood cells. The iron in the red blood cell is required
for the formation of hemoglobin. It allows the hemoglobin molecule to transport oxygen. This makes iron critical to the oxygentransporting function of the red blood cell.
White blood cells or leukocytes are critical in the fight
against inflammation and infection. White blood cells are
divided into two types:
1. Granulocytes. The granulocytes are further differentiated into
neutrophils, eosinophils, and basophils. Approximately twothirds of all white blood cells are neutrophils. They have a very
short life span (about 10 hours), so the bone marrow is constantly replacing them. The neutrophils increase in number
in response to inflammation in the body. The eosinophils and
basophils respond primarily to allergic reactions.
2. Agranulocytes. The agranulocytes are divided into monocytes and lymphocytes. The monocytes kill bacteria and
respond to the presence of foreign materials in the body.
The lymphocytes are formed in lymphatic tissue and are
needed for a healthy immune system.
Platelets are elements in the blood that are necessary for
proper blood coagulation. The production of platelets is controlled by thrombopoietin (a protein manufactured by the
liver, the kidney, the smooth muscle, and the bone marrow).
The release of thrombopoietin is controlled by the number of
platelets present in the blood. Table 26-1 ■ provides normal
values for a complete blood count.
Collaborative Care
LABORATORY TESTS
There are many laboratory tests that can indicate disorders of
the hematopoietic and lymphatic systems. All clients will first
have a complete blood count (CBC). This blood test measures
TABLE 26-1
Complete Blood Count with Normal Values
LABORATORY TEST
NORMAL VALUES
Red Blood Cell (RBC)
RBC count
■ Men
■ Women
4.2–5.4 million/mm3
3.6–5.0 million/mm3
Reticulocyte count
1–1.5% of total RBC
Hemoglobin (Hgb)
■ Men
■ Women
14–16.5 g/dL
12–15 g/dL
WHAT TEST MEASURES
Number of circulating RBCs per cubic millimeter of blood
Number of immature RBCs in 1 mm3 of blood
Amount of hemoglobin in 100 mL (1 dL) of blood
Hematocrit (Hct)
■
■
Men
Women
Packed volume of RBCs in 100 mL of blood; reported
as a percentage
40–50%
37–47%
Mean corpuscular volume
(MCV)
85–100 cubic micrometers
(µm3) per cell
Average volume of individual RBCs
Mean corpuscular
hemoglobin (MCH)
31–35 g/dL
Weight of the hemoglobin in an average RBC
Mean corpuscular hemoglobin
concentration (MCHC)
33.4–35.5%
Average concentration (percent) of hemoglobin
within RBC
5,000–10,000/mm3
Number of WBCs per cubic millimeter of blood
White Blood Cells (WBCs) and Platelets
WBC count
Differential WBC count:
Number of neutrophils released by bone marrow
3
■
Neutrophils
60–70% or 3,000–7,000/mm
■
Eosinophils
Basophils
Lymphocytes
Monocytes
1–3% or 50–400/mm3
0.3–0.5% or 25–200/mm3
20–30% or 1,000–4,000/mm3
3–8% or 100–600/mm3
■
■
■
Active phagocytes; first to respond to inflammation or
infection
Respond to allergic reaction and parasitic infestations
Respond to allergic and inflammatory reactions
Involved in immune reactions
Active in disposing of foreign and waste material,
especially in inflammation