McKenna's Pharmacology for Nursing, 2e

480

P A R T 5  Drugs acting on the autonomic nervous system

■■ Beta-blockers are drugs used to block the beta- receptors within the SNS. These drugs are used for a wide range of conditions, including hypertension, stage fright, migraines, angina and essential tremors. ■■ Non-selective blockade of all beta-receptors results in a loss of the reflex bronchodilation that occurs with sympathetic stimulation. This limits the use of these drugs in individuals who smoke or have allergic or seasonal rhinitis, asthma or COPD. possible changes in dose to achieve therapeutic effectiveness, to enhance knowledge about drug therapy and to promote compliance. Evaluation ■ ■ Monitor response to the drug (lowering of blood pressure, decrease in anginal episodes, improvement in condition being treated). ■ ■ Monitor for adverse effects (GI upset, CNS changes, respiratory problems, CV effects, loss of libido and impotence). ■ ■ Evaluate the effectiveness of the teaching plan (person can name drug, dosage, adverse effects to watch for and specific measures to avoid them). ■ ■ Monitor the effectiveness of comfort measures and compliance with the regimen. CRITICAL THINKING Why did M.R. have such a severe reaction? What appropriate measures should be taken to ensure that M.R. recovers fully and does not re-experience this event? What sort of support will M.R. and his family need after going through such a frightening experience? Think about the children who may have witnessed the respiratory arrest and how they should be reassured, depending on their ages. Think about the support M.R.’s wife may need and the fear that may now be associated with M.R.’s condition. M.R. has been taking propranolol for several months and needs to decide whether he should continue the drug with modifications to his lifestyle or the addition of other drugs to deal with his respiratory issues. What kind of teaching program will need to be developed to help M.R. deal with this drug, and its potential adverse effects? KEY POINTS

myocardium to catecholamines, and severe reactions could occur. ■ ■ Continuously monitor any individual receiving an IV form of these drugs to avert serious complications caused by rapid sympathetic blockade. ■ ■ Monitor blood pressure, pulse, rhythm and cardiac output regularly to evaluate drug effectiveness and to monitor for changes that may indicate a need to adjust dose or discontinue the drug if cardiovascular effects are severe. ■ ■ Arrange for supportive care and comfort measures (rest, environmental control, other measures) to relieve CNS effects ; institute safety measures if CNS effects occur to prevent injury; provide small, frequent meals and mouth care to help relieve the discomfort of GI effects ; establish a daily activity program, spacing activities to help the person deal with activity intolerance . ■ ■ Offer support and encouragement to help the person deal with the drug regimen. ■ ■ Provide thorough teaching, including drug name, dose and schedule of administration; use of drug with food or meals, if appropriate; possible adverse effects and measures to prevent them; warning signs to report; safety measures, such as changing position slowly, avoiding driving or using hazardous machinery, and pacing activities; and the need for follow-up evaluation and

CRITICAL THINKING SCENARIO Non-selective beta-blockers (propranolol)

THE SITUATION M.R., a 59-year-old man, has been seen several times complaining of tremor in his hands that eventually made it very difficult for him to work as a computer programmer. A diagnosis of essential tremor was made, and he was prescribed propranolol ( Inderal ) 40 mg twice daily. M.R. had good effects with the drug and had no further problems until the following June, when acute respiratory distress developed while he was picnicking in a state park with his family. On the way to the emergency room, he suffered an apparent respiratory arrest. He was admitted to the hospital and placed in the respiratory intensive care unit. It was found that M.R. had a history of hay fever and allergic rhinitis during the pollen season but had never experienced such a severe reaction.