Opioid Agonists/Antagonists Flashcards
What is naloxone and how does it work?
Naloxone is a pure opioid antagonist that blocks opioid receptor
sites resulting in reversal of respiratory depression and
analgesia produced by opioids.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 155.
What opioid receptors does naloxone antagonize?
Naloxone acts as a pure antagonist at mu, kappa, and delta
receptors but has the highest affinity for mu receptors.
Longnecker DE, Newman MF, Brown DL, Zapol WM.
Anesthesiology. 2nd ed. New York: McGraw-Hill; 2012: 721.
What is the onset of action and duration of naloxone?
Naloxone has an onset of about 1-2 minutes. The duration is
dose-dependent, but 0.2 mg intravenously last about 30-45
minutes.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 289.
What is the suggested dose of naloxone for
ventilatory depression.
In the face of postoperative ventilatory depression or apnea,
naloxone should be administered in doses of 20-40 mcg every
few minutes until spontaneous breathing is adequate, but
analgesia has not been reversed.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 289.
What is the usual dose for a naloxone infusion?
Respiratory depression can be prevented by administering an
initial loading dose of naloxone followed by an infusion of 4-5
mcg/kg/hour.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 289.
When would a naloxone infusion be appropriate?
Because naloxone is short-acting, it is possible that the
antagonist effects of the naloxone could wear off before the
effects of the opioid administered did. As the naloxone’s action
terminated, the patient could become sedated again and
ventilatory depression could ensue once more. An initial
loading dose of naloxone followed by an infusion can prevent
this from occurring.
Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Stock MC,
Ortega R. Clinical Anesthesia. 7th ed. Philadelphia, PA:
Lippincott Williams and Wilkins; 2013: 517.
What are the potential hazardous effects of naloxone
administration?
The sudden reversal of opioid analgesic effects can produce
severe pain that can result in tachycardia, hypertension,
ventricular arrhythmias, and severe and possibly fatal
pulmonary edema.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 289.
Name the four categories into which opioids are
commonly divided.
Agonists, antagonists, partial agonists, and agonist-antagonists.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 145.
Upon what receptors does nalbuphine exert its
action?
Nalbuphine is an opioid derivative that acts as a partial agonist
at both mu and kappa receptors. Most studies indicate that
nalbuphine acts to antagonize mu receptor activity and agonize
kappa receptor activity.
Longnecker DE, Newman MF, Brown DL, Zapol WM.
Anesthesiology. 2nd ed. New York: McGraw-Hill; 2012: 722.
What is the indication for naloxone use during
laparoscopic cholangiography?
Full-agonist opioids can produce spasm of the sphincter of
Oddi, making cholangiography more difficult to perform.
Intravenous naloxone in 40 mcg increments has been shown to
relieve this condition by antagonizing the effects of the opioid
that produces the spasm.
Jaffe RA, Samuels SI. Anesthesiologist’s Manual of Surgical
Procedures. 4th ed. Philadelphia, PA: Lippincott Williams and
Wilkins, 2009: 566.
How can nalbuphine be used in a manner similar to
naloxone and what are the advantages of
nalbuphine in this setting?
Nalbuphine produces an analgesic effect that reaches a
maximum effect equivalent to 0.4 mg/kg of morphine. Because
it is only a partial agonist, it can be used to reverse the
respiratory effects of full-agonist opioids like fentanyl. The
advantage of nalbuphine over naloxone is that patients
experience much less reversal of analgesia.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 155.
What is the difference between naltrexone and
naloxone?
Naltrexone is a long-acting oral opioid antagonist. Naloxone is
administered intravenously.
Longnecker DE, Newman MF, Brown DL, Zapol WM.
Anesthesiology. 2nd ed. New York: McGraw-Hill; 2012: 722.
What is the prototypical opioid agonist?
Morphine
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 152.
Why should you use caution with or completely avoid
the administration of partial opioid agonists to
patients with narcotic addiction?
Partial agonists such as nalbuphine, pentazocine, and
butorphenol are opioid agonist-antagonists that can produce
withdrawal symptoms if administered to an opioid-dependent
patient.
Longnecker DE, Newman MF, Brown DL, Zapol WM.
Anesthesiology. 2nd ed. New York: McGraw-Hill; 2012: 705.
How does butorphanol differ from nalbuphine?
Butorphanol is similar to nalbuphine in that it is a kappa
receptor agonist and a weak mu receptor antagonist, but it has
greater analgesic qualities than nalbuphine and produces more
sedation when used clinically.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 155.
