A nurse is reviewing laboratory results for a client who takes acetaminophen for osteoarthritis pain management.Which of the following findings should alert the nurse to possible hepatotoxicity? (Select all that apply.).

The correct answer is choice B.Methadone blocks the euphoric effects of heroin and discourages its use.Methadone is a synthetic opioid analgesic that produces a cross-tolerance to other narcotics, thereby preventing the user from feeling the high of heroin.Methadone also reduces withdrawal symptoms and cravings for heroin.

Choice A is wrong because methadone does not prevent withdrawal symptoms, but rather reduces them.

Choice C is wrong because methadone does not stimulate opioid receptors, but rather occupies them and blocks their activation by heroin.

Choice D is wrong because methadone does not reverse the respiratory depression caused by heroin overdose, but rather carries a risk of overdose itself.

The correct answer is choice B. Administer Percocet every six hours around the clock for two days.

This is because the patient has been receiving a continuous infusion of morphine via a PCA pump, which means that they have a steady level of opioids in their system.

If the PCA pump is discontinued abruptly and the patient is switched to oral analgesics PRN, they may experience withdrawal symptoms and inadequate pain relief.

Therefore, the patient needs to receive a scheduled dose of oral opioids for at least two days to prevent a sudden drop in opioid blood concentration and to maintain adequate analgesia.

After two days, the patient’s pain level and opioid requirement may be reassessed and the oral analgesics may be tapered or given PRN as needed.

Choice A is wrong because a higher dose of Percocet is not necessary if the patient reports satisfactory pain relief with the current PCA settings.The equivalent oral dose of morphine for the patient’s average PCA consumption is about 120 mg per day (20 mg x 6 doses), which is equivalent to about 80 mg of oxycodone per day (1.5 x 120 mg).

The prescribed dose of Percocet is 20 mg of oxycodone per day (5 mg x 4 doses), which is about 25% of the patient’s previous opioid requirement.This reduction is appropriate to account for incomplete cross-tolerance between different opioids.

Choice C is wrong because stopping morphine one hour before giving Percocet will not prevent a gap in analgesia.The half-life of morphine is about 2 to 4 hours, which means that it takes about 10 to 20 hours for morphine to be eliminated from the body.

Therefore, stopping morphine one hour before giving Percocet will not significantly reduce the morphine blood concentration and will not avoid the risk of additive effects or overdose.

Choice D is wrong because giving Percocet only if the patient reports breakthrough pain will not provide adequate pain relief for the patient who has been receiving a continuous infusion of morphine via a PCA pump.

The patient may experience withdrawal symptoms and increased pain sensitivity if the opioid blood concentration drops suddenly.

Therefore, the patient needs to receive a scheduled dose of oral opioids for at least two days to prevent a gap in analgesia and to allow a smooth transition from IV to oral opioids.