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Unit 3
Applying concepts from the nursing process
the underlying cancer, any temperature of 38.3°C or higher
is reported and dealt with promptly. The nurse monitors the
patient for sepsis, particularly if invasive catheters or infusion
lines are in place.
WBC function is often impaired in patients with cancer.
There are five types of WBCs: neutrophils (granulocytes), lym-
phocytes, monocytes, basophils and eosinophils. Neutrophils,
which comprise 60 to 70% of all the body’s WBCs, serve as the
body’s primary defence against invading organisms by engulf-
ing and destroying infective organisms through phagocytosis.
Both the total WBC count and the concentration of neutro
phils are important in determining the patient’s ability to
fight infection. A decrease in circulating WBCs is referred to
as leucopenia. Granulocytopenia is a decrease in neutrophils.
A differential WBC count identifies the relative numbers of
WBCs and permits tabulation of polymorphonuclear neutro-
phils or segmented neutrophils (mature neutrophils, reported
as ‘polys’, PMNs or ‘segs’) and immature forms of neutrophils
(reported as bands, metamyelocytes, and ‘stabs’). The absolute
neutrophil count (ANC) is calculated by the following
formula:
For example, if the total WBC count is 6 × 10
9
/L with
segmented neutrophils 25% and bands 25%, the ANC is
3 × 10
9
/L.
Neutropenia
, an abnormally low ANC, is associated with
an increased risk for infection. The risk for infection rises as
the ANC decreases. As the ANC declines below 1.5 × 10
9
/L,
the risk for infection increases. An ANC less than 0.5 × 10
9
/L
reflects a severe risk of infection (Marrs, 2006).
Nadir
is the
lowest ANC after myelosuppressive chemotherapy or radiation
of active disease treatment, desire for the use of life support
measures, and symptom management. Support, which can be
as simple as holding the patient’s hand or just being with the
patient at home or at the bedside, often contributes to peace
of mind. See Chapter 12 for further discussion of end-of-life
issues.
Monitoring and managing potential complications
Infection
For patients in all stages of cancer, the nurse assesses factors
that can promote infection. Although the infection-associated
mortality rate has decreased, infection remains a major cause of
morbidity and mortality in patients with cancer (Zitella et al.,
2006). Defence against infection is compromised in many dif-
ferent ways. The integrity of the skin and mucous membrane,
the body’s first line of defence, is challenged by multiple
invasive diagnostic and therapeutic procedures, by adverse
effects of radiation and chemotherapy, and by the detrimental
effects of immobility.
Factors predisposing patients to infection are summarised
in Table 11-9. Often, more than one predisposing factor is
present in patients with cancer (Friese, 2007). The nurse
monitors laboratory studies to detect early changes in WBC
counts. Common sites of infection, such as the pharynx, skin,
perianal area, urinary tract and respiratory tract, are assessed
on a regular basis. However, the typical signs of infection
(swelling, redness, drainage and pain) may not occur in immu-
nosuppressed patients because of decreased circulating white
blood cells and a diminished local inflammatory response.
Fever may be the only sign of infection in the immunocom-
promised patient (Marrs, 2006). Although fever may be
related to a variety of non-infectious conditions, including
Table 11-9 Factors Predisposing Cancer Patients to Infection
Factors
Underlying mechanisms
1. Impaired skin and mucous
• Loss of body’s first line of defence against invading organisms.
membrane integrity
2. Chemotherapy
• Many agents cause suppression of bone marrow, resulting in decreased
production and function of white blood cells. Chemotherapy agents that cause mucositis impair skin and mucous
membrane integrity. Organ damage associated with certain agents may also predispose patients to infection. Organ
damage such as pulmonary fibrosis or cardiomyopathy that is associated with certain agents may also predispose
patients to infection.
3. Radiation therapy
• Radiation involving sites of bone marrow production may result in bone
marrow suppression. May also lead to impaired tissue integrity.
4. Biological response modifiers
• Some biological response modifiers may cause bone marrow suppression and organ dysfunction.
5. Malignancy
• Malignant cells may infiltrate the bone marrow and interfere with production of white blood cells and lymphocytes.
Haematological malignancies (leukaemias and lymphomas) are associated with impaired function and production of
blood cells.
6. Malnutrition
• Results in impaired function and production of cells of the immune response. May contribute to impaired skin
integrity.
7. Medications
• Antibiotics disturb the balance of normal flora, allowing them to become pathogenic. This process occurs
most commonly in the gastrointestinal tract. Corticosteroids and non-steroidal anti-inflammatory drugs mask
inflammatory responses.
8. Urinary catheter
• Creates port and mechanism of entry for organisms.
9. Intravenous catheter
• Results in impaired skin integrity and site of entry for organisms.
10. Other invasive procedures
• Creates port of entry and possible introduction of exogenous organisms
(surgery, paracentesis,
into the system.
thoracentesis, drainage
tubes, endoscopies,
mechanical ventilation)
11. Contaminated equipment
• Environmental objects such as stagnant water in oxygen equipment are associated with growth of microorganisms.
12. Age
• Increasing age associated with declining organ function. Also associated with decreased production and functioning of
the cells of the immune system.
13. Chronic illness
• Associated with impaired organ function and altered immune responses.
14. Prolonged hospitalisation
• Allows increased exposure to nosocomial infection and colonisation of new organisms.
