Chapter 29: Sedative-Hypnotic Drugs
A nurse is discussing the use of benzodiazepines as sedative-hypnotic agents with a group of nursing students. A student asks about the actions of these drugs in the central nervous system. The nurse makes which correct statement? a. "Benzodiazepines affect the hippocampus and the cerebral cortex to cause anterograde amnesia." b. "Benzodiazepines depress neuronal functions by acting at a single site in the brain." c. "Benzodiazepines induce muscle relaxation by acting on sites outside the centralnervous system." d. "Benzodiazepines promote sleep through effects on the limbic system."
A: "Benzodiazepines affect the hippocampus and the cerebral cortex to cause anterograde amnesia." All beneficial and most adverse effects of benzodiazepines occur from depressant actions in the central nervous system (CNS); the various effects depend on the site of action. Anterograde amnesia is the result of effects in the hippocampus and the cerebral cortex. Benzodiazepines act at multiple sites in the CNS. Muscle relaxant effects are the result of actions on supraspinal motor areas in the CNS. Benzodiazepines promote sleep through effects on cortical areas and on the sleep-wakefulness "clock."
A patient takes temazepam [Restoril] for insomnia. The patient tells the nurse that a recent telephone bill lists several calls to friends that the patient does not remember making. What will the nurse do? a. Ask the patient about any alcohol consumption in conjunction with the benzodiazepine. b. Contact the prescriber to request an order for a benzodiazepine with a shorter duration. c. Reassure the patient that this is most likely caused by a paradoxical reaction to the benzodiazepine. d. Tell the patient that this is an example of anterograde amnesia, which is an expected effect of the benzodiazepine
A: Ask the patient about any alcohol consumption in conjunction with the benzodiazepine. This patient is describing complex sleep-related behavior, which occurs when patients carry out complex behaviors while taking benzodiazepines but have no memory of their actions. These actions can occur with normal doses but are more likely with excessive doses or when benzodiazepines are combined with alcohol or other CNS depressants, so the nurse is correct in evaluating this possibility. The duration of the benzodiazepine does not contribute to this phenomenon. Paradoxical effects of benzodiazepines include insomnia, excitation, euphoria, anxiety, and rage. Anterograde amnesia occurs when patients have impaired recall of events that occur after dosing
A patient in the emergency department is given intravenous diazepam [Valium] for seizures. When the seizures stop, the nurse notes that the patient is lethargic and confused and has a respiratory rate of 10 breaths/minute. The nurse will expect to administer which of the following? a. Flumazenil [Romazicon] b. Gastric lavage c. Respiratory support d. Toxicology testing
C: Respiratory support When benzodiazepines are administered IV, severe effects, including profound hypotension, respiratory arrest, and cardiac arrest, can occur. Respiration should be monitored, and the airway must be managed if necessary. Flumazenil [Romazicon] is a competitive benzodiazepine receptor antagonist and is used to reverse the sedative effects but may not reverse respiratory depression. Gastric lavage would not be effective, because the benzodiazepine has been given IV. Without further indication ofthe ingestion of other drugs, toxicologytesting is not a priority
A patient who travels frequently for business reports occasional instances of being unable to fall asleep. The patient tells the nurse that job demands require staying up late and then getting up early for meetings. The nurse expects that the provider will prescribe which medication for this patient? a. Flurazepam b. Trazodone [Desyrel] c. Zaleplon [Sonata] d. Zolpidem [Ambien]
C: Zaleplon [Sonata] Zaleplon [Sonata] works well for people who have trouble falling asleep and, because of its short duration of action, can be taken late at night without causing a hangover or next-daysedation early in the morning. Zolpidem [Ambien] has a longer duration and is a good choice for patients who have difficulty maintaining sleep. Flurazepam has a long duration of action. Trazodone causes daytime grogginess
A hospitalized patient who is given one dose of flurazepam continues to show drowsiness the next day. A nursing student asks the nurse the reason for this, because the drug's half-life is only 2 to 3 hours. Which response by the nurse is correct? a. "Benzodiazepines commonly cause residual effects lasting into the day after the dose is given." b. "The patient is having a paradoxical reaction to this medication." c. "This patient must have developed a previous tolerance to benzodiazepines." d. "When this drug is metabolized, the resulting compound has longer-lasting effects."
D: "When this drug is metabolized, the resulting compound has longer-lasting effects." Flurazepam has a half-life of 2 to 3 hours; however, its metabolite has a long half-life, so giving the drug results in long-lasting effects. Barbiturates, not benzodiazepines, are commonly associated with residual, or hangover, effects. A paradoxical reaction to a sedative would manifest as insomnia, euphoria, and excitation, not drowsiness. Tolerance meansthat the patient would need increased amounts of a drug to get the desired effects and would not have prolonged effects ofthe medication
A patient who has been using secobarbital for several months to treat insomnia tells the nurse that the prescriber has said the prescription will be changed to temazepam [Restoril] because it issafer. The patient asks why this agent issafer. The nurse is correct in telling the patient that temazepam: a. does not depress the central nervous system. b. shows no respiratory depression, even in toxic doses. c. mimics the actions of a central nervous system inhibitory neurotransmitter. d. potentiates endogenous gamma-aminobutyric acid (GABA) producing a finiteCNS depression.
D: potentiates endogenous gamma-aminobutyric acid (GABA) producing a finiteCNS depression. Benzodiazepines potentiate the actions of GABA, and because the amount of GABA in the CNS is finite, these drugs' depressive effect on the CNS is limited. Benzodiazepines depress the CNS but not to the extent that barbiturates do. Benzodiazepines are weak respiratory depressants at therapeutic doses and moderate respiratorydepressants at toxic doses. Barbiturates mimic GABA; therefore, because they produce CNS depression, this effect is limited only by the amount of barbiturate administered
A patient who is experiencing alcohol withdrawal is given a benzodiazepine. The nurse understands that this drug is effective because: a. the alcohol does not interact with the benzodiazepine. b. the benzodiazepine potentiates alcohol withdrawal symptoms. c. the benzodiazepine relieves muscle spasms and spasticity. d. the patient has a cross-dependence to the benzodiazepine.
D: the patient has a cross-dependence to the benzodiazepine. Benzodiazepines are given to ease withdrawal from alcohol because of cross-dependence with these drugs and alcohol, enabling the benzodiazepine to suppress withdrawal symptoms. Alcohol and benzodiazepines can potentiate one another. The benzodiazepine does not potentiate withdrawal symptoms
A patient with a new-onset seizure disorder receives a prescription for phenobarbital. The patient reports being concerned about the sedative side effects ofthis drug. Which response by the nurse is correct? a. "Phenobarbital doses for seizures are nonsedating." b. "This is a short-acting barbiturate, so sedation wears off quickly." c. "Tolerance to the sedative effects will develop in a few weeks." d. "You may actually experience paradoxical effects of euphoria.
a. "Phenobarbital doses for seizures are nonsedating." Phenobarbital and mephobarbital are used for seizure disorders and suppress seizures at dosesthat are nonsedative. Phenobarbital is a long-acting barbiturate. At therapeutic doses, sedative effects do not occur. Paradoxical drug effects are associated with benzodiazepines and in older adults and debilitated patients with barbiturates
