DIP Episode 40 - Neuro Pharmacology Part 3 (Anesthetics and Opioids)

Source / episode info

**Episode:**40
**Title:**Divine Intervention Episode 40 – Neuro Pharmacology Part 3 (Anesthetics and Opioids).
**Published:**2018-07-20
Source:Episode page

One-liner

This episode covers the pharmacology of inhaled anesthetics (MAC, BG coefficient), IV agents like Propofol/Ketamine, local anesthetic principles (size matters), opioid receptor effects (miosis, constipation), and headache syndromes (Triptans for acute migraine).

High-yield summary

Inhaled Anesthetics: Low Blood Gas Partition Coefficient -> Quick Onset. Low Minimum Anesthetic Concentration (MAC) -> High Potency/High Lipid Solubility.
Propofol Infusion Syndrome (PRIS): Associated with Propofol administration, characterized by metabolic acidosis and hyperkalemia.
Triptans: Used for acute migraine treatment; contraindicated in patients with history of coronary vasospasm or variant angina due to risk of worsening vasoconstriction.
Opioid Effects: Opioids decrease GI motility, leading to constipation and causing miosis (via decreased sympathetic tone). The exception is myperidine, which is a muscarinic receptor antagonist and causes mydriasis.
Neuromuscular Blockers (NMB): Non-depolarizing agents are competitive antagonists at nicotinic receptors; reversal with acetylcholinesterase inhibitors (e.g., Neostigmine) requires co-administration of a muscarinic antagonist (e.g., Glycopyrrolate) to prevent parasympathomimetic side effects.
Headache Syndromes: Cluster headaches are classically unilateral, associated with ipsilateral lacrimation and rhinorrhea ("tearing/runny nose"). Acute treatment is 100% oxygen.

Learning objectives

Differentiate between the concepts of MAC and Blood Gas Partition Coefficient in inhaled anesthetics.
Identify the clinical manifestations and management pitfalls associated with Propofol administration.
Apply knowledge of triptan indications and contraindications in migraine management.
Explain the mechanism and necessary adjuncts for reversing non-depolarizing neuromuscular blockers.
Recognize the unique physiological effects (e.g., mydriasis, constipation) of various opioid agonists.