Skeletal Muscle Relaxants Lecture Notes

A set of flashcards summarizing key concepts related to skeletal muscle relaxants, their mechanisms of action, uses, and effects.

What are neuromuscular blocking agents (NMBDs)?

Agents that cause paralysis of skeletal muscles by acting at the neuromuscular junction.

What is the key active compound found in curare?

d-tubocurarine.

What type of neuromuscular blocking agent is d-tubocurarine classified as?

Prototype non-depolarizing neuromuscular blocking agent.

What is the mechanism of action (MOA) for non-depolarizing NMBDs?

They compete with acetylcholine for nicotinic receptors at the neuromuscular junction.

What are some clinical uses for NMBDs?

Facilitating surgery, intubation, and as adjuncts to general anesthesia.

What are the phases of succinylcholine block?

Phase I: muscle stuck on (cannot contract); Phase II: muscle reset but receptor unresponsive.

What are some adverse effects associated with succinylcholine?

Mild hyperkalemia, rise in intraocular pressure, potential for malignant hyperthermia.

What does the term 'competitive block' refer to in the context of neuromuscular blocking agents?

The competition between NMBDs and ACh at the nicotinic receptors, leading to muscle paralysis.

How do you reverse the effects of non-depolarizing NMBDs?

Using acetylcholinesterase inhibitors such as neostigmine or edrophonium.

What is the primary action of dantrolene?

It inhibits Ca²+ release from the sarcoplasmic reticulum, leading to muscle relaxation.

What is the significance of pseudocholinesterase deficiency?

It can lead to prolonged paralysis after administration of succinylcholine.

How does guaifenesin function as a muscle relaxant?

By blocking internuncial neurons within the brain and spinal cord to reduce muscle hyperactivity.