McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 4 9 Drugs used to treat anaemias

Care considerations for people receiving erythropoiesis-stimulating agents

subcutaneous injection to achieve appropriate therapeutic drug levels. ■ ■ Provide the person with a calendar of marked days to aid in remembering dates for injection and promote increased compliance with the drug regimen. ■ ■ Do not mix with any other drug solution to avoid potential incompatibilities ■ ■ Monitor access lines for clotting and arrange to clear line as needed. ■ ■ Ensure that prescribed laboratory testing, such as haematocrit levels, is completed before drug administration to determine correct dose. If the person does not respond within 8 weeks, re-evaluate the cause of anaemia. Anticipate a target haemoglobin range between 10 and 12 g/dL. ■ ■ Evaluate iron stores before and periodically during therapy because supplemental iron may be needed as the person makes more RBCs. ■ ■ Maintain seizure precautions on standby in case seizures occur as a reaction to the drug. ■ ■ Provide comfort measures to help the person tolerate the drug effects. These include small, frequent meals to help minimise nausea and vomiting; readily available access to bathroom facilities should diarrhoea occur; and analgesia for headache or arthralgia. ■ ■ Offer support and encouragement to help the person deal with the diagnosis and the drug regimen. ■ ■ Provide thorough teaching, including the name of the drug, dosage prescribed, administration technique and frequency of administration, measures to avoid adverse effects, warning signs of problems and need to notify healthcare provider, and the need for follow-up laboratory testing, to enhance knowledge about drug therapy and to promote compliance. Evaluation ■ ■ Monitor response to the drug (alleviation of anaemia, target haemoglobin level a maximum of 12 g/dL). ■ ■ Monitor the effectiveness of comfort measures and compliance with the regimen. ■ ■ Evaluate the effectiveness of the teaching plan (person can name drug, dosage, adverse effects to watch for and specific measures to avoid them; person understands the importance of continued follow-up). ■ ■ Monitor for adverse effects (headache, hypertension, nausea, vomiting, seizures, dizziness).

Assessment: History and examination

■ ■ Assess for contraindications or cautions: any known allergies to any component of the drug to avoid hypersensitivity reactions ; severe hypertension, which could be exacerbated ; and breastfeeding because of potential adverse effects on the neonate. These drugs should be used with caution in people with anaemia and normal renal function to prevent rebound decrease in normal erythropoietin production and in people with cancer receiving the drugs to increase haematocrit after antineoplastic chemotherapy because of the risk of rapid tumour progression if haemoglobin levels exceed guidelines. ■ ■ Perform a physical assessment to establish a baseline before beginning therapy and during therapy to determine drug effectiveness and evaluate any potential adverse effects. ■ ■ Assess neurological status, including affect, orientation and muscle strength, to identify possible adverse CNS effects. ■ ■ Monitor vital signs, including pulse and blood pressure, for changes , and assess cardiovascular status, to identify possible cardiovascular effects ; and inspect lower extremities for evidence of oedema, which could indicate a change in cardiovascular function. ■ ■ Assess respirations and auscultate lungs for adventitious breath sounds for early detection of changes in cardiovascular function. ■ ■ Monitor the results of laboratory tests, including renal function tests, full blood count (FBC), haematocrit, iron concentration, transferrin and electrolyte levels, to evaluate the effectiveness of therapy. Be aware of variations in haematological test results due to race (see Box 49.2). Implementation with rationale ■ ■ Confirm the chronic, renal nature of the person’s anaemia before administering the drug to treat renal failure anaemia to ensure proper use of the drug. ■ ■ Give epoetin alfa three times per week, either intravenously or subcutaneously, to achieve appropriate therapeutic drug levels. Administer darbepoetin alfa once per week, subcutaneously or intravenously. Administer methoxy polyethylene glycol-epoetin beta once every 2 weeks, and then once a month when the person is stabilised, by