Question

1. Describe the anatomy of the somatic nervous system, the key transmitter and receptor type involved in skeletal muscle activation, and the physiologic consequences of activating those cell receptors.

2. Compare and contrast the mechanisms of action of nondepolarizing and depolarizing neuromuscular blocking agents and state how these actions influence the use of one class rather than the other in specified clinical situations.

3. Identify three specific uses for neuromuscular blocking agents and describe the monitoring and other measures necessary with their use.

4. Discuss the main risks and main cause of death with neuromuscular blocking agents and describe steps to manage potentially fatal responses.

5. Identify the class of drugs used to reverse the effects of nondepolarizing neuromuscular blockers and describe the mechanism by which they cause that reversal. Also explain why pharmacologic reversal is not used when succinylcholine is the neuromuscular blocker.

6. Describe the etiology, signs, and symptoms of malignant hyperthermia; the drugs associated with a high risk for that condition; and interventions to be implemented should it develop. 7. Discuss the rationale for the limited applications of mecamylamine.

Answer 1

1, Somatic nervous system is a part of peripheral nervous system responsible for transfer motor and sensory information to CNS..The system responsible for voluntary muscle movement and sensory information processing that comes from external stimuli like hearing,touch and sight..it is play a important role in initiating and controlling the movement of our body..
Agonist binds rapidly with low affinity in agonist different  rate..channel closing open if agonist binding site are occupied by Ach(acetylcholine) and there is AchR activation..Channel open allow an influx of sodium ions into cytoplasm of the muscle fiber,muscle fiber begins when acetylcholine binds to receptors of the muscle fiber membrane..when acetylcholine reaches receptors on the membranes muscle fibers,membrane channel open the process of contraction and relaxation of muscle fibers begins..
2,Neuromuscular blocking agents block the binding of acetylcholine to the motor end plate..As per their action it is divided into depolirarizing or nondepolarizing agent used for intubation or treat laryngospasm. Non depolarizing NMBAs inhibit the Ach receptors on the motor end plate..Drug binding to the Ach receptor to prevent the conformational change or physically obstruct the ion channels,so end plate not generated non polarizing NMBA divided into Amininosteroid compounds and benzylisoquinolinium compounds..
3, Neuromuscular blocking agent used for depends on patients factors..
-For endotracheal intubation as a short and long duration of neuromuscular block is required..
-It is a skeletal muscle relaxant acting as a ultra short-acting depolarizing type
- during therapeutic treatment or during procedure it is used for long sedation..
It is recover the neuromuscular function to be carefully monitored to avoid overdose and detect development of phase II block..Ensure patient is fully ventilated on a controlled rate of breathing..Assess pupil reaction and size every 4hourly..Maintain continuous analgesia and sedation during administration of neuromuscular blocking agent..
4, Neuromuscular block may cause neuromuscular transmission failure by desensitation,depolarization block and open channel block of the acetylcholine receptors..it can impair upper airway dilator volume,genioglossus muscle function and diaphramatic functions..Anaphylactic reactions to neuromuscular blocking agents are severe and even fatal.. ongoing betablocker treatment and surgery for male genders,obesity,a history of cardiovascular disease it is high risk of fatal outcome after neuromuscular blocking agent induced anaphylaxis..epinephrine-resistant cause high mortality due to hypersensitivity of NMBA make fatal mortality rate..