Hematologic and Immunologic Systems

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Hematologic and Immunologic Systems


Physiologic Anatomy

1. Hematologic system

a. Anatomic structures

i. Bone marrow

ii. Liver

b. Components: See Table 7-1 and Figure 7-1

c. Functions: See Table 7-2 and Figure 7-2

2. Immunologic system

a. Anatomic structures

i. Bone marrow (see preceding description)

ii. Thymus

iii. The lymph system is a separate vessel system that collects plasma and leukocytes that are not returned to the circulatory system from the tissue capillary beds. This lymph fluid is filtered and returned to the circulatory system, so that appropriate tissue fluid pressures are maintained and edema is prevented. Lymph fluid is propelled along the system by the normal contraction of skeletal muscles.

(a) Lymph fluid is a pale yellow liquid made up of plasma, leukocytes, enzymes, and antibodies; it lacks clotting factors and thus coagulates very slowly

(b) Lymphatic capillaries and vessels are a network of open-ended tubes with one-way valves that collect lymph fluid from the tissues and eventually return it to the venous system via both the right lymphatic duct, which drains into the right subclavian vein, and the thoracic duct, which drains into the left subclavian vein

(c) Lymph nodes are small, flat, bean-shaped patches of tissue located along the length of the lymphatic system that filter microorganisms from the lymph fluid before it is returned to the bloodstream

iv. The spleen is a lymphoid organ located in the upper left quadrant of the abdomen that clears damaged or nonfunctioning RBCs and filters antigens from the blood for evaluation by lymphocytes

b. Components: See Tables 7-3, 7-4, and 7-5, and Figure 7-3


Functions of Eicosanoids


Data from Boron W, Boulpaep EL: Medical physiology, Philadelphia, 2003, Saunders. EET, Cis-epoxyeicosatrienoic acid; HETE, hydroxyeicosatetraenoic acid.

c. Functions: See Table 7-6

Patient Assessment

1. Nursing history

a. Patient health history

i. Many times a hematologic or immunologic problem is identified when the patent seeks medical attention for some other reason

ii. Elements of the medical history indicating a potential or existing hematologic or immunologic problem include the following:

iii. Review of systems with the patient and/or family for signs and symptoms

(a) General: Fatigue, weakness, lethargy, malaise, fever, chills, night sweats, dyspnea, restlessness, apprehension, pain, altered mental status, vertigo, dizziness, confusion

(b) Skin: Pruritus, change in skin color, rash, unusual bruising, ulcers or other lesions

(c) Head and neck: Headache, change in vision, sinus pain, epistaxis, gingival bleeding, sore throat, pain with swallowing, enlarged lymph nodes

(d) Respiratory: Cough, hemoptysis, dyspnea, orthopnea

(e) Cardiovascular: Palpitations, dizziness with position changes

(f) Gastrointestinal: Change in eating habits, anorexia, abdominal fullness, nausea, vomiting, hematemesis, change in bowel habits, hematochezia, melena, pain with defecation, change in weight

(g) Genitourinary: Hematuria, pain with urination, menorrhagia, enlarged inguinal lymph nodes

(h) Musculoskeletal: Swelling of joints, tenderness or pain in the bones or joints

(i) Endocrine: Heat or cold intolerance

b. Family history indicating a potential hematologic or immunologic problem: Hemophilia, sickle cell anemia, cancer, or death of a relative at a young age for reasons other than trauma

c. Social history and habits that may assist with the diagnosis and treatment of the underlying condition, including the following:

d. Medication history

i. Current medications or a recent change in medication may suggest an underlying hematologic or immunologic problem. Always ask about over-the-counter medication use, because many of these preparations contain aspirin or nonsteroidal antiinflammatory drugs (NSAIDs).

ii. Many medications used to treat nonhematologic and nonimmunologic problems can affect the hematologic and immunologic systems; examples of these drugs are the following:

(a) Analgesics and antiinflammatory drugs

(b) Antibiotics, such as

(c) Anticoagulants, such as

(d) Anticonvulsants, such as

(e) Antidiabetic agents, such as chlorpropamide

(f) Antineoplastic chemotherapy agents, such as

(g) Antipsychotic agents, such as clozapine (Clozaril)

(h) Antirheumatic agents, such as

(i) Cardiovascular agents, such as

(j) Diuretics, such as chlorothiazide (Diuril)

(k) Hormones, such as

(l) Immunosuppressives, such as

(m) Oral contraceptives

2. Nursing examination of patient

a. Physical examination data

i. Inspection

ii. Palpation and percussion

iii. Auscultation

b. Monitoring data

3. Appraisal of patient characteristics: Patients needing acute or life-saving care for hematologic disorders or for immunologic compromise come to critical care units as a result of their comorbidities or primary complications. The need for critical care may be brief or extended with quick to no recovery. Many hematologic and immunologic disorders are incurable. Occasionally, the focus is anticipated end-of-life care, although in no case is one able to predict with any certainty. Some patient characteristics that the nurse needs to assess for this population are the following:

a. Resiliency

b. Vulnerability

c. Stability

d. Complexity

e. Resource availability

f. Participation in care

g. Participation in decision making

h. Predictability

4. Diagnostic studies

a. Laboratory: See Table 7-7 for normal values


Normal Blood Values

Laboratory Test Reference Values Description
(White blood cell (WBC) count 4500-10,000/mm3 Total number of leukocytes
Differential WBC:   Part of CBC; indicates distribution of five types of leukocytes
 Neutrophils 2500-7000/mm3  
  Segments 2500-6500/mm3  
  Bands 0-500/mm3  
 Monocytes 200-600/mm3  
 Basophils 40-100/mm3  
 Eosinophils 100-300/mm3  
 Lymphocytes 1700-3500/mm3  
Red blood cell (RBC) indices:   Erythrocyte indicators for anemia
 RBC count    
  Men 4.6-6.0 million/mm3  
  Women 4.0-5.0 million/mm3  
 Mean corpuscular volume (MCV) 80-98 mm3 Indicates size of RBC
 Mean corpuscular hemoglobin (MCH) 27-31 pg Indicates weight of hemoglobin in RBC
 Mean corpuscular hemoglobin concentration (MCHC) 32%-36% Hemoglobin per volume RBC
 RBC distribution width (RDW) 11.5-14.5 Coulter S Size (width) difference of RBCs
Hemoglobin (Hb) level   Iron composition of RBC for oxygen-carrying capability
 Men 13.5-17 g/dl  
 Women 11.2-115 g/dl  
Hematocrit (HCT) of blood   Measure of the percentage of the total blood volume that is made up by RBCs
 Men 40%-54%  
 Women 36%-46%  
 Panic value <15% and >60%  
Reticulocyte count 0.5%-1.5% Indicator of bone marrow activity
Erythrocyte sedimentation rate   Rate at which erythrocytes settle (sediment) in unclotted blood
 Men 0-9 mm/hr (Wintrobe method)  
 Women 0-15 mm/hr (Wintrobe method)  
Serum ferritin level   An indicator of protein stores of iron in the tissues, where 1 ng/ml ferritin = 8 mg stored iron
 Men 15-445 ng/ml  
 Women 10-235 ng/ml  
 Postmenopausal 15-310 ng/ml  
Total iron-binding capacity (TIBC) 250-450 mg/dl Total (maximum) iron-binding capacity of transferrin for transport of iron to marrow for hemoglobin synthesis
Platelet count (PLT) 150,000-400,000/mm3 Measure of thrombocytes available for coagulation of blood
Fibrin split products (FSP) 2-10 mg/ml Indicator of fibrin degradation products acting as anticoagulant in continuous bleeding associated with hemorrhage
Clotting times 10-13 sec Measures clotting factor ability
 Prothrombin time (PT)    
 Partial thromboplastin time (PTT) 60-70 sec Detects deficiencies in clotting factors
 International normalized ratio (INR) 2.5-3.5 Standard for warfarin-sensitive PT

Data from Kee JL: Laboratory diagnostic tests with nursing implications, ed 5, Stamford, Conn, 1999, Appleton & Lange.

b. Radiologic

c. Biopsy

d. Skin tests: Barometers of immune functioning, pointing out hyposensitivities or hypersensitivities to a particular antigen. Examples of allergens used in skin testing are allergenic extracts (e.g., dust, pollen, animal dander); purified protein derivative (PPD) for tuberculin skin tests; mumps virus; Candida albicans; and skin fungi.

Patient Care

1. Susceptibility to infection

a. Description of problem

b. Goals of care

c. Collaborating professionals on health care team

d. Interventions: See Table 7-9


Leukocyte Intervention Activity Bundle


From Schneider S: Interventions for hematologic problems. In Ignatavicius DD, Workman ML, editors: Medical-surgical nursing: critical thinking for collaborative care, ed 4, Philadelphia, 2002, Saunders.

e. Evaluation of patient care

2. Increased risk for hemorrhage

a. Description of problem

b. Goals of care

c. Collaborating professionals on health care team

d. Interventions: See Table 7-10

TABLE 7-10

Erythrocyte Intervention Activity Bundle


From Schneider S: Interventions for hematologic problems. In Ignatavicius DD, Workman ML, editors: Medical-surgical nursing: critical thinking for collaborative care, ed 4, Philadelphia, 2002, Saunders.

e. Evaluation of patient care

3. Impaired respiratory gas transport: See Chapter 2

4. Impaired fluid volume regulation (see also Chapter 5)

a. Description of problem

b. Goals of care

c. Collaborating professionals on health care team

d. Interventions: See Table 7-11

TABLE 7-11

Dehydration Intervention Activity Bundle


LOC, Level of consciousness.

From Schneider S: Interventions for hematologic problems. In Ignatavicius DD, Workman ML, editors: Medical-surgical nursing: critical thinking for collaborative care, ed 4, Philadelphia, 2002, Saunders.

i. Administer IV fluids and blood products as prescribed

(a) Transfuse blood products (Table 7-12)

TABLE 7-12

Indications for Treatment with Blood Components


From Schneider S: Interventions for clients with hematologic problems. In Ignatavicius DD, Workman ML, editors: Medical-surgical nursing: critical thinking for collaborative care, ed 4, Philadelphia, 2002, Saunders, chap 40.

(b) Keep in mind special considerations related to blood product administration (Table 7-13 and Box 7-1)


1. Alloimmunization is a state in which the patient develops antibodies against human leukocyte antigen (HLA), granulocyte-specific antigens, red blood cell (RBC)–specific antigens, or platelet-specific antigens after repeated blood product transfusions. As a result, the transfused cells are destroyed and the transfusion is ineffective in correcting the patient’s blood counts. Platelet destruction related to HLA antibodies accounts for 95% of cases of alloimmunization in patients who fail to respond to platelet transfusions. HLA matching and platelet cross-matching are two options for patients with alloimmunization. For both of these options, nearly 2 days can be required to provide a proper match.

2. Pathogen contamination of blood products has been reduced due to better screening of donors, viral nucleic acid testing of donor blood, purification of plasma and plasma-derived products, and recombinant factor concentrate production technology. Current estimated risk of transmission of viruses ranges from 0.5 to 7.0 per million transfusions. However, 1 in 500 to 2000 platelet transfusions has bacterial contamination. Consideration should be given to the rate at which new blood-borne pathogens are identified and the inability to outpace growth with appropriate screening tests. Pathogen inactivation technologies are actively being studied.

3. Irradiation of blood products incapacitates lymphocytes, with approximately 2500 rads of gamma radiation thus reducing the incidence of cytomegalovirus (CMV) infection, alloimmunization, and transfusion-associated graft-versus-host disease (GVHD). Cryoprecipitate and fresh frozen plasma are lymphocyte free and need not be irradiated. Irradiation of blood is beneficial for immunocompromised patients at risk for GVHD, hematopoietic stem cell donors, and transplant patients, and in cases of cellular (T-cell) immunodeficiency, intrauterine transfusion, transfusions from family members, matched platelet transfusions, Hodgkin’s disease, neonatal exchange transfusions, acute myelogenous leukemia, acute lymphocytic leukemia, and lymphoma.

4. CMV-negative blood products are necessary for patients who need a bone marrow transplant and who have never been exposed to CMV. A CMV infection during transplantation could be life-threatening. Use of CMV-negative blood products benefits premature infants or infants younger than 4 weeks of age, fetuses undergoing intrauterine transfusions, and any CMV-negative patient who is pregnant, potentially a transplant candidate, about to undergo splenectomy, or has acquired immunodeficiency syndrome, human immunodeficiency virus infection, or a congenital immune deficiency.

5. Leukocyte-reduced (LR) blood products reduce the risk of developing a nonhemolytic transfusion reaction, alloimmunization, or GVHD, and potentially prevent the transmission of CMV. When administering LR blood products, be sure to use an appropriate blood filter at the bedside to trap the cellular debris accumulated since the original filtration process. Leukocyte reduction benefits patients with a history of more than one nonhemolytic febrile transfusion reaction, immunocompromised patients at risk for CMV, and patients who will potentially receive multiple transfusions and are at an increased risk for alloimmunization.

6. Washing of blood removes proteins, electrolytes, antibodies, and glycerol (from frozen RBCs) that could trigger severe reactions in some recipients. To wash blood, 0.9% normal saline is added to the unit and mixed, the mixture is centrifuged, and the saline is removed. Washing of blood benefits patients receiving RBCs frozen in glycerol and patients exhibiting severe hypersensitivity to donor plasma components such as immunoglobulin A or B.

7. Blood substitutes