Textbook of Medical-Surgical Nursing 3e

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Chapter 11

Oncology: Nursing management in cancer care

Patients with neutropenia are treated with broad-spectrum antibiotics before the infecting organism is identified because of the high incidence of mortality associated with untreated infection. Broad-spectrum antibiotic coverage or empiric therapy most often includes a combination of medications to defend the body against the major pathogenic organisms. An important component of the nurse’s role is to administer these medications promptly according to the prescribed schedule to achieve adequate blood levels of the medications. Strict asepsis is essential when handling intravenous lines, catheters and other invasive equipment. Exposure of the patient to others with an active infection and to crowds is avoided. Patients with profound immunosuppression, such as BMT recipients, may need to be placed in a protective environ­ment where the room and its contents are sterilised and the air is filtered. These patients may also receive low-bacteria diets, avoiding fresh fruits and vegetables. Hand hygiene and appropriate general hygiene are necessary to reduce exposure to potentially harmful bacteria and to eliminate environmental contaminants. Invasive procedures, such as injections, vaginal or rectal examinations, rectal temperatures, and surgery, are avoided. The patient is encouraged to cough and perform deep-breathing exercises frequently to prevent atelectasis and other respiratory problems. Prophylactic antimicrobial therapy may be used for patients who are expected to be profoundly immunosuppressed and at risk for certain infections. The nurse teaches the patient and family to recognise signs and symptoms of infection to report, perform effective hand hygiene, use antipyretics, maintain skin integrity and administer haemato- poietic growth factors when indicated. Septic shock The nurse assesses the patient frequently for infection and inflammation throughout the course of the disease. Septicaemia and septic shock are life-threatening complications that must be prevented or detected and treated promptly. Patients with signs and symptoms of impending sepsis and septic shock require immediate hospitalisation and aggressive treatment in the ICU setting. Signs and symptoms of septic shock (see Chapter 8) include altered mental status, either subnormal or elevated tempera- ture, cool and clammy skin, decreased urine output, hypo- tension, arrhythmias, electrolyte imbalances and abnormal arterial blood gas values. The patient and family members are instructed about signs of septicaemia, methods for prevent- ing infection and actions to take if infection or septicaemia occurs. Septic shock is most often associated with overwhelming Gram-negative bacterial infections; however, patients with prolonged neutropenia or haematological malignancies are also more susceptible to fungal and viral sources of sepsis as well. The nurse monitors the blood pressure, pulse rate, respira­ tions and temperature of the patient with shock every 15 to 30 minutes. Neurological assessments are carried out to detect changes in orientation and responsiveness. Fluid and electrolyte status is monitored by measuring fluid intake and output and serum electrolytes. Arterial blood gas values and pulse oximetry are monitored to determine tissue oxygenation. The nurse administers intravenous fluids, blood products and vasopressors as prescribed to maintain the patient’s blood pressure and tissue perfusion. Supplemental

therapy that suppresses bone marrow function. Febrile patients who are neutropenic are assessed for factors that increase the risk for infection and for sources of infection through cultures of blood, sputum, urine, stool, IV or urinary catheters, and wounds, if appropriate. In addition, a chest x-ray is often obtained to assess for pulmonary infections. Defence against infection is compromised in many differ- ent ways. The integrity of the skin and mucous membranes is challenged by multiple invasive diagnostic and therapeutic procedures, by adverse effects of radiation and chemotherapy, and by the detrimental effects of immobility. Impaired nutrition as a result of anorexia, nausea, vomiting, diarrhoea and the underlying disease alters the body’s ability to combat invading organisms. Medications such as antibiotics disturb the balance of normal flora, allowing the overgrowth of normal flora and pathogenic organisms. Other medications can also alter the immune response (see Chapter 50). Cancer itself may lead to defects in cellular and humoral immunity. Advanced cancer can cause obstruction of the hollow viscera (e.g. intestines), blood vessels and lymphatic vessels, creating a favourable environment for proliferation of pathogenic organ- isms. In some patients, tumour cells infiltrate bone marrow and prevent normal production of WBCs. However, most often, a decrease in WBCs is a result of bone marrow suppression after chemotherapy or radiation therapy. Severe neutropenia may necessitate delays in administration of myelosuppressive ther- apies or treatment dose adjustments, although the use of the haematopoietic growth factors, also called colony-stimulating factors (see previous discussion), has reduced the severity and duration of neutropenia associated with myelosuppressive chemo­therapy and radiation therapy. The administration of these factors assists in reducing the risk for infection and, possibly, in maintaining treatment schedules, drug dosages, treatment effectiveness and quality of life. Nurses are in a key position to assist in preventing and identify­ing symptoms of infection, as discussed in the Plan of nursing care (see Chart 11-4). Although multiple infection control practices are employed, there is a signif- icant lack of evidence to support many of them (Zitella et al., 2006). Clinical practice guidelines developed by the Oncology Nursing Societies are used to guide interventions. Interventions to prevent infection and education formats to teach patients and families about infection are high research priorities. Gram-positive organisms, such as Streptococcus and Staphylococcus species, are the most frequently isolated causes of infection. Gram-negative organisms, such as Escherichia coli and Pseudomonas aeruginosa, and fungal organisms, such as Candida albicans, also contribute to the incidence of serious infection. Viral infections in immunocompromised patients are caused most often by herpes viruses and respiratory viruses. Fever is probably the most important sign of infection in immunocompromised patients. In neutropenic patients, any one-time temperature of 38.3°C or higher or 38.0°C or higher for 1 hour or more is reported and dealt with promptly. Antibiotics may be prescribed to treat infections after cultures of wound exudate, sputum, urine, stool or blood are obtained. Careful consideration is given to the underlying malignancy, prior antineoplastic treatment, absolute neutrophil count, comorbidities and other patient-related factors prior to the identification of the most appropriate initial antibiotic therapy.