Textbook of Medical-Surgical Nursing 3e

241

Chapter 11

Oncology: Nursing management in cancer care

diarrhoea may occur if the stomach or colon is in the irradiated field. Symptoms subside and gastrointestinal reepithelialisation occurs after treatments are complete. Bone marrow cells proliferate rapidly, and if bone-marrow producing sites (e.g. sternum and iliac crest) are included in the radiation field, anaemia, leucopenia (decreased white blood cells [WBCs]) and thrombocytopenia (a decrease in platelets), may result. Patients are then at increased risk for infection and bleeding until blood cell counts return to normal. Chronic anaemia may occur (Bruner et al., 2006). Research to develop cytoprotective agents that can protect normal tissue from radiation damage continues. The most commonly used cytoprotectant is amifostine (Ethyol), which is utilised in head and neck cancer patients to reduce acute and chronic xerostomia while preserving anti-tumour efficacy (Bruner et al., 2006; Hogle, 2007). Certain systemic side effects are also commonly experienced by patients receiving radiation therapy. These manifestations, which are generalised, include fatigue, malaise and anorexia. This syndrome may be secondary to substances released when tumour cells break down. The effects are temporary and subside with the cessation of treatment. Late effects of radiation therapy may also occur in various body tissues. These effects are chronic, usually produce fibrotic changes secondary to a decreased vascular supply, and are irreversible. These late effects can be most severe when they involve vital organs such as the lungs, heart, central nervous system and bladder. Toxicities may intensify when radiation is combined with other treatment modalities. Nursing management in radiation therapy The patient receiving radiation therapy and the family often have questions and concerns about its safety. To answer ques- tions and allay fears about the effects of radiation on others, on the tumour, and on the patient’s normal tissues and organs, the nurse can explain the procedure for delivering radiation and describe the equipment, the duration of the procedure (often minutes only), the possible need for immobilising the patient during the procedure, and the absence of new sensations, including pain, during the procedure. If a radioactive implant is used, the nurse informs the patient and family about the restrictions placed on visitors and healthcare personnel and other radiation precautions. Patients also need to understand their own role before, during and after the procedure. See Chapter 42 for further discussion of radiation treatment for gynaecological cancers. If systemic symptoms, such as weakness and fatigue, occur, the nurse explains that these symptoms are a result of the treat- ment and do not represent deterioration or progression of the disease. The assessment and nursing management of fatigue is discussed in more detail in the Plan of nursing care of patients with cancer, Chart 11-4. Protecting carers When a patient has a radioactive implant in place, nurses and other healthcare providers need to protect themselves as well as the patient from the effects of radiation. Specific instruc- tions are usually provided by the radiation safety officer from the x-ray department. The instructions identify the maximum time that can be spent safely in the patient’s room, the shield- ing equipment to be used, and special precautions and actions to be taken if the implant is dislodged. The nurse should

explain the rationale for these precautions to keep the patient from feeling unduly isolated. Contacts with the healthcare team are guided by principles of time, distance and shielding to minimise exposure of person- nel to radiation because patients receiving internal radiation emit radiation while the implant is in place. Safety precau- tions used in caring for the patient receiving brachytherapy include assigning the person to a private room, posting appro- priate notices about radiation safety precautions, having staff members wear dosimeter badges, making sure that pregnant staff members are not assigned to the patient’s care, prohibit- ing visits by children or pregnant women, limiting visits from others to 30 minutes daily, and seeing that visitors maintain a 2-metre distance from the radiation source. Patients with seed implants typically are able to return home; radiation exposure to others is minimal. Information about any precautions, if needed, is provided to the patient and family members to ensure safety. Depending on the dose and energy emitted by a systemic radionuclide, patients may or may not require special precautions or hospitalisation (Bruner et al., 2006). The nurse should explain the rationale for these precautions to keep the patient from feeling unduly isolated. Chemotherapy In chemotherapy , antineoplastic agents are used in an attempt to destroy tumour cells by interfering with cellular functions and reproduction. Chemotherapy is used primarily to treat systemic disease rather than lesions that are localised and amenable to surgery or radiation. Chemotherapy may be combined with surgery or radiation therapy, or both, to reduce tumour size preoperatively, to destroy any remaining tumour cells postoperatively, or to treat some forms of leukaemia. The goals of chemotherapy (cure, control, palliation) must be real- istic because they will define the medications to be used and the aggressiveness of the treatment plan. Cell kill and the cell cycle Each time a tumour is exposed to a chemotherapeutic agent, a percentage of tumour cells (20% to 99%, depending on dosage) is destroyed. Repeated doses of chemotherapy are necessary over a prolonged period to achieve regression of the tumour. Eradication of 100% of the tumour is nearly impos- sible, but a goal of treatment is to eradicate enough of the tumour so that the remaining tumour cells can be destroyed by the body’s immune system. Actively proliferating cells within a tumour (growth fraction) are the most sensitive to chemotherapeutic agents. Non-dividing cells capable of future proliferation are the least sensitive to antineoplastic medications and consequently are potentially dangerous. The non-dividing cells must be destroyed, however, to eradicate a cancer completely. Repeated cycles of chemother- apy are used to kill more tumour cells by destroying these non- dividing cells as they begin active cell division. Reproduction of both healthy and malignant cells follows the cell cycle pattern (Figure 11-1). The cell cycle time is the time required for one tissue cell to divide and reproduce two identical daughter cells. The cell cycle of any cell has four distinct phases, each with a vital underlying function:  1. G 1 phase—RNA and protein synthesis occur.  2. S phase—DNA synthesis occurs.  3. G 2 phase—premitotic phase; DNA synthesis is complete, mitotic spindle forms.  4. Mitosis—cell division occurs.