chemotherapy

(kē″mō-ther′ă-pē )

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[ chemo- + therapy ]
Drug therapy used to treat infections, cancers, and other diseases and conditions.
Descriptive text is not available for this imageCancer chemotherapeutic agents are potentially toxic and may pose risks both to the professionals who handle them (pharmacists and nurses) and to the patients who receive them. Usually, only oncology practitioners specifically trained in chemotherapy administration should perform this task. The most important factor in reducing exposure is proper protection in the preparation and administration of these agents. After washing their hands, health care providers should don indicated protective equipment and ensure patient safety by reviewing that the drug is being given to the right patient, at the right dose and time, via the right route. Hydration is provided before administration, along with (as indicated) antiemetic, antihistamine, or other adjunctive medications. All chemotherapy waste and equipment must be discarded in designated containers. Health care providers must follow guidelines when cleaning up drug spills. Treatment with cancer chemotherapy may contribute to risks to female reproductive health, reductions in blood cell counts, nausea, vomiting, constipation, fatigue, oral sores, and hair loss, among other complications. Careful monitoring of patients posttreatment is required.

PATIENT CARE
Cancer chemotherapeutic agents include alkylating agents and nitrosureas, antimetabolites, antitumor antibiotics, plant alkaloids, monoclonal antibodies, immunomodulating agents, and steroid hormones. Antineoplastic agents kill cancer cells but also kill or injure normal cells, esp. those that normally divide rapidly and may therefore compromise the patient's comfort and safety. Bone marrow suppression is a common and potentially serious adverse reaction. Chemotherapy can decrease the numbers of leukocytes, erythrocytes, and platelets. Leukopenia increases the patient's risk for infection, esp. if the granulocyte count falls below 1000/mm3. Patients are given information to help with prevention and recognition of infection, including signs and symptoms such as fevers, chills, cough, sore throat, rashes, or burning during urination. They are advised to physically distance themselves from others, esp. individuals with cold or flu symptoms. Blood cell stimulating medications or hormones are provided, when needed, to support low white cell counts, platelets, or red blood cells. Patients are assessed for bleeding gums, increased bruising, petechiae, heavy menses, tarry stools, coffee-ground emesis, or blood in urine. They are advised to take precautions to avoid cuts, bruises, and burns, and should be educated to report dizziness, fatigue, pallor, or easily triggered shortness of breath (these may suggest anemia). They should use a stool softener to reduce the risk of colonic bleeding. Intramuscular injections are avoided. Oral irritation and ulceration may interfere with eating and drinking. Preventive oral care is provided, but when irritation proves very painful or limits the ability to eat or swallow, oral mouthwashes and medications may be prescribed.

The patient may experience nausea and vomiting from gastric mucosal irritation (from oral or parenteral chemotherapy), chemical irritation of the central nervous system (from parenteral chemotherapy), or psychogenic factors activated by sensations, suggestions, or anxiety. Chemotherapy-induced nausea and vomiting are troublesome because they can cause fluid and electrolyte imbalance, noncompliance with the treatment regimen, tears at the esophageal-gastric junction that lead to massive bleeding (Mallory-Weiss syndrome), wound dehiscence, and pathological fractures. They also reduce quality of life by interfering with the patient's ability and motivation to take an active role in self-care. Such complications are assessed for and prevented as much as possible. Chemical irritation is controlled by administering prescribed combinations of antiemetics that act by different mechanisms, e.g., serotonin antagonists, prochlorperazine, diphenhydramine, droperidol, and dronabinol. Signs and symptoms of aspiration are monitored because most antiemetics are sedating. Psychogenic factors can be relieved by relaxation techniques to minimize feelings of isolation and anxiety before and during each treatment. The patient is encouraged to express feelings of anxiety, listen to music, engage in relaxation techniques, meditation, or self-hypnosis to help promote feelings of well-being and a sense of control.

Hair loss is distressing for the patient, esp. when the patient's body image or self-esteem is closely linked to his or her appearance. The patient is informed that hair loss usually is gradual, affects both men and women, and may be partial or complete, depending on the drug or drug combination employed. He or she is reassured that alopecia is reversible after treatment ends. A wig can be prescribed as a cranial prosthesis (for insurance coverage of the expense). The patient is encouraged to purchase it before hair loss begins and is informed where to acquire one. Although some patients prefer to expose their baldness, the scalp should be protected from exposure to the sun. Some chemotherapeutic agents have irreversible effects such as peripheral neuropathy although treatment is available to reduce these.

Chemotherapy extravasation may lead to tissue necrosis if the drug is a vesicant, and the patient is taught to immediately report any pain, stinging, burning, swelling, or redness at the injection site. Extravasation must be distinguished from vessel irritation or flare reaction. Vein irritation is felt as aching or tightness along the blood vessel, and the length of the vein may become reddened or darkened, accompanied by swelling. In flare reaction, itching is the major complaint; redness occurs in blotches along the vessel, may look like hives, and subsides within 30 min. Blood return from the IV can usually be obtained with both irritation and flare reaction. To help prevent extravasation, most known vesicant drugs are administered through a central venous catheter. If extravasation is suspected, the infusion is stopped, and any drug is aspirated. The extremity is elevated, and cold compresses are applied, except for Vinca alkaloids, for which heat is recommended. Depending on agency protocol, the oncologist is notified, and, if a specific antidote for the drug exists, it is administered as prescribed. The main line IV provides direct access to the patient if an undesired reaction occurs; other drugs can be administered quickly to counteract the adverse reaction. SEE TABLE: Important Considerations in the Administration of Chemotherapy

Complementary and alternative therapies are often used to help patients undergoing chemotherapy to feel better and more in control of their illness and its treatment.

Important Considerations in the Administration of Chemotherapy
• Has the patient had allergic reactions to this medication in the past?
• What fluids are compatible, or incompatible, with the agent to be administered?
• What is the exact dosage for this patient's body size and weight?
• How is the drug mixed or prepared?
• What is the proper route of administration?
• How stable is the drug once prepared?
• How should it be stored?
• What other drugs is the patient taking? Are any likely to cause drug interactions?
• Can the drug cause skin or vein irritation during administration? How will these complications be managed?
• What is the anticipated schedule of administration?
• What are the specific side effects of the agent? How should the patient and health care team prepare for early or delayed effects?
• How are effects of the drug to be monitored?
• How often should the patient have physical examinations, imaging studies, or blood tests?
• What findings suggest further drug administration should be delayed or cancelled?
• Who should the patient contact with concerns?

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SUBCUTANEOUS PORT

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