McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 3 3 Anticholinergic agents

Care considerations for people receiving anticholinergic agents

■■ Atropine is the most commonly used anticholinergic drug. It is indicated for a wide variety of conditions and is available in oral, parenteral and topical forms. ■■ People receiving anticholinergic drugs must be monitored for dry mouth, difficulty swallowing, constipation, urinary retention, tachycardia, pupil dilation and photophobia, cycloplegia and blurring of vision, and heat intolerance caused by a decrease in sweating. to alleviate photophobia ; small and frequent meals to alleviate GI discomfort ; bowel program, including a high-fibre diet, to alleviate constipation ; safety precautions, such as side rails if appropriate, assistance with ambulation and advice to avoid driving or operating hazardous machinery to prevent injury if CNS effects are severe ; analgesics to relieve pain if headaches occur ; voiding before taking medication if urinary retention is a problem (commonly occurs with benign prostatic hyperplasia); and encouraging fluid intake and monitoring heat exposure because the ability to sweat will be reduced. ■ ■ Monitor response closely, including blood pressure, electrocardiogram, urine output and cardiac output, for changes that may indicate a need to adjust dose to ensure benefit with the least amount of toxicity. ■ ■ Offer support and encouragement to help the person deal with the drug regimen. ■ ■ Provide thorough teaching about drug name, dosage and schedule for administration; proper technique for topical application, if appropriate (see Focus on safe medication administration); measures to minimise or prevent adverse effects; safety measures such as avoiding driving, avoiding operating hazardous machinery, staying hydrated and monitoring exposure to heat; dietary recommendations if appropriate; warning signs of problems and the need to report these; and importance of follow-up monitoring and evaluation. Evaluation ■ ■ Monitor response to the drug (improvement in disorder being treated). ■ ■ Monitor for adverse effects (cardiovascular changes, GI problems, CNS effects, urinary hesitancy and retention, pupil dilation and photophobia, decrease in sweating and heat intolerance). ■ ■ Evaluate the effectiveness of the teaching plan (person can name drug, dosage, adverse effects to watch for and specific measures to avoid them, proper administration of ophthalmic drugs). ■ ■ Monitor the effectiveness of comfort measures and compliance with the regimen.

Assessment: History and examination

■ ■ Assess for contraindications or cautions: any known allergies to these drugs to avoid hypersensitivity reactions ; glaucoma; stenosing peptic ulcer, intestinal atony, paralytic ileus, GI obstruction, severe ulcerative colitis and toxic megacolon; prostatic hypertrophy and bladder obstruction; cardiac arrhythmias, tachycardia and myocardial ischaemia, all of which could be exacerbated by parasympathetic blockade ; impaired liver or kidney function, which could alter the metabolism and excretion of the drug ; myasthenia gravis, which could worsen with further blocking of the cholinergic receptors ; pregnancy because of the potential for adverse effects on the fetus ; breastfeeding because of possible suppression of breastfeeding ; hypertension because of the possible additive hypertensive effects ; and muscle spasticity and brain damage, which could be exacerbated by cholinergic blockade. See the Critical thinking scenario to learn more about care for the person who has heart disease and is taking anticholinergic drugs. ■ ■ Perform a physical assessment, including a review of all body systems, to establish baseline status before beginning therapy, determine drug effectiveness and evaluate for any potential adverse effects. ■ ■ Assess neurological status, including level of orientation, affect, reflexes and papillary response, to evaluate any CNS effects. ■ ■ Monitor vital signs and cardiopulmonary status, including pulse, blood pressure, heart rate and heart sounds; auscultate lung sounds. Obtain an electrocardiogram if ordered to identify changes in heart rate or rhythm. ■ ■ Assess abdomen; auscultate bowel sounds. Evaluate bowel and bladder patterns; monitor urinary output; palpate bladder for possible distension to evaluate for GI and GU adverse effects. ■ ■ Monitor the results of laboratory tests, including renal function studies, to determine need for possible dose adjustment and to identify potential toxicity. Implementation with rationale ■ ■ Ensure proper administration of the drug to ensure effective use and decrease the risk of adverse effects (see Focus on safe medication administration). ■ ■ Provide comfort measures to help the person tolerate drug effects : sugarless lozenges to suck and frequent mouth care to alleviate problems associated with dry mouth ; lighting control

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