McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 5 9 Antiemetic agents

CRITICAL THINKING SCENARIO Handling postoperative nausea and vomiting

THE SITUATION A.J. is a 16-year-old boy who has undergone reconstructive knee surgery after a football injury. After the surgery, A.J. complains of nausea and vomits three times in 2 hours. A.J. becomes increasingly agitated. Intravenous prochlorperazine ( Stemetil ) is ordered to relieve the nausea, to be followed by an oral order when tolerated. The prochlorperazine is somewhat helpful in relieving the nausea. CRITICAL THINKING What are the important nursing implications in this case? What other measures could be taken to relieve A.J.’s nausea? DISCUSSION It is often impossible to pinpoint an exact cause of a person’s nausea and vomiting in a hospital setting. For example, the underlying cause may be related to the pain, a reaction to the pain medication being given, or a response to what A.J. described as the “awful hospital smell”. A combination of factors should be considered when dealing with nausea and vomiting. A.J., as a teenager, may become increasingly agitated by the discomfort and possible embarrassment of vomiting. The administration of prochlorperazine may “take the edge off” the nausea. A.J. will have to be reminded that the drug he is being given may make him dizzy, weak or drowsy and that he should ask for assistance if he needs to move. Once the nausea and vomiting diminish somewhat, it will be possible to try other interventions to help stop the vomiting reflex. One such intervention is removing the offending odour that A.J. described, if possible, because doing so may relieve a chemical stimulus to the chemoreceptor trigger zone (CTZ). Administration of pain medication, as prescribed, may relieve the CTZ stimulus that comes with intense pain. Other interventions include providing a serene, quiet environment and encouraging A.J. to take slow, deep breaths, which stimulate the parasympathetic system (vagus nerve) and partially override the sympathetic activity stimulated by the CTZ to activate vomiting. For many people, mouth care, ice chips or small sips of water may also help to relieve the discomfort and ease the sensation of nausea. CARE GUIDE FOR A.J.: ANTIEMETICS Assessment: History and examination Assess A.J.’s health history for allergies to any antiemetic, coma, CNS depression, severe hypotension, liver

dysfunction, bone marrow depression, epilepsy and concurrent use of alcohol, anticholinergic drugs, barbiturate anaesthetics and guanethidine. Determine the type and amount of anaesthesia used. Focus the physical examination on the following areas: Neurological: orientation, affect Skin: colour, lesions Cardiovascular: pulse, blood pressure, orthostatic blood pressure Gastrointestinal: abdominal and liver evaluation Laboratory tests: haematological, full blood count, liver function tests Implementation Administer antiemetics only as a temporary measure. Provide comfort and safety measures, including assistance with mobility, access to bathroom, safety precautions, mouth care and ice chips. Monitor A.J. for dehydration and provide remedial measures as needed. Provide support and reassurance for coping with drug effects and discomfort. Provide teaching regarding drug name, dosage, adverse effects, precautions and warnings to report. Evaluation Evaluate drug effects, for example, relief of nausea and vomiting. Monitor for adverse effects, including GI alterations, orthostatic hypotension, dizziness, confusion, sensitivity to sunlight and dehydration. Monitor for drug–drug interactions as appropriate. Evaluate the effectiveness of the teaching program and comfort and safety measures. TEACHING FOR A.J. • The drug that has been prescribed for you is called prochlorperazine . It belongs to a class of drugs called antiemetics. An antiemetic helps to prevent nausea and • Dizziness, weakness : Change positions slowly. If you feel drowsy, avoid driving or dangerous activities for at least 24 hours after the last dose of this drug (such as the use of heavy machinery or tasks requiring coordination). • Sensitivity to the sun : Avoid exposure to the sun and ultraviolet light because serious reactions may occur. If exposure cannot be prevented, use sunscreen and protective clothing to cover the skin. vomiting and the discomfort they cause. • Common effects of this drug include: