1. What ASA/ABA wants you to know
about Opioids

2. 1) mechanism of action
• Receptors: mu, kappa, delta, sigma
• Pre/post synaptic
• Calcium
• Peri-aq. Grey and dorsal horn

3. 2) pharmacokinetics and
pharmacodynamics
• Lipid solubility
• Vd = dose/[drug]
• Fentanyl, Morphine, Hydromorphine,
Methadone, Remifentanyl
• Context sensitive half-life

4. 3) metabolism and excretion
• Liver Metabolism/Renal Excretion
• Morphine
• Meperidine
• Hydromorphone
• Methadone
• Fentanyl

5. 4) effect on circulation
• Meperidine heart rate and contractility
• MAP decrease: brady (vagus), venodilation,
decreased SNS tone, histamine release

6. 5) effect on respiration
• Apneic Threshold
• Morphine and Meperidine Bronchospasm
• Chest wall rigidity
• Block bronchoconstriction to intubation

7. 6) effect on other organs
• Brain – reduce CRMO2, CBF, ICP
• Minimal EEG change, no reliable amnesia
• EEG activation with meperidine
• N/V – medullary chemoreceptor trigger
zone

8. 7) side effects and toxicity
• Meperidine and MAOI
• GI – reduce peristalsis, biliary spasm
• Endocrine – block release of
catecholamines, ADH, cortisol better than
VA.
• Immune suppression, REM disturbance,
hypogonadism, hyperalgesia,
addiction/overdose.

9. 8) indications and contraindications
• Cancer pain
• Perioperative period
• Chronic pain?
• OHS, pregnancy, meperidine,
combinations,

10. 8) indications and contraindications
• Cancer pain
• Perioperative period
• Chronic pain?
• OHS, pregnancy, meperidine,
combinations,