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Unit 3   Applying concepts from the nursing process

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

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

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. • Some biological response modifiers may cause bone marrow suppression and organ dysfunction. • 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. • Results in impaired function and production of cells of the immune response. May contribute to impaired skin integrity. • 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. • Radiation involving sites of bone marrow production may result in bone marrow suppression. May also lead to impaired tissue integrity.

3. Radiation therapy

4. Biological response modifiers

5. Malignancy

6. Malnutrition

7. Medications

8. Urinary catheter 9. Intravenous catheter

• Creates port and mechanism of entry for organisms. • Results in impaired skin integrity and site of entry for organisms. • Creates port of entry and possible introduction of exogenous organisms

10. Other invasive procedures

(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. • Increasing age associated with declining organ function. Also associated with decreased production and functioning of the cells of the immune system.

12. Age

13. Chronic illness

• Associated with impaired organ function and altered immune responses. • Allows increased exposure to nosocomial infection and colonisation of new organisms.

14. Prolonged hospitalisation