Neuromuscular blocking agents succinylcholine

A. May potentiate agents metabolized by the cholinesterase enzyme (eg, depolarizing neuromuscular blocking agents—succinylcholine, cocaine, esmolol), cholinesterase inhibitors (eg, organophosphate and carbamate insecticides), and other cholinergic agents (eg, pilocarpine). 

Anesthesia - Galantamine is likely to exaggerate the neuromuscular blockade effects of succinylcholine-type and similar neuromuscular blocking agents during anesthesia. 

A decrease in stability is often a desirable modification. For example, succinylcholine (suxamethonium 3.25) — a neuromuscular blocking agent used in surgery — has a self-limiting activity, since the ester is hydrolyzed in about 10 minutes, preventing the potential for overdose, which could be fatal with more stable curarizing agents. 

Succinylcholine is a neuromuscular blocking agent, which is used clinically to cause muscle relaxation. Its duration of action is short due to rapid metabolism—hydrolysis by cholinesterases (pseudocholinesterase or acylcholine acyl hydrolase)—in the plasma and liver to yield inactive products (Fig. 7.55). Thus, the pharmacological action is terminated by the metabolism. However, in some patients, the effect is excessive, with prolonged muscle relaxation and apnea lasting as long as two hours compared with the normal duration of a few minutes. 

Seizures induced by local anesthetics can also be treated with small doses (given intravenously) of thiopental 1-2 mg/kg, propofol 0.5-1 mg/kg, midazolam 2-4 mg total dose, or diazepam 0.1 mg/kg. The muscular manifestations of seizures can be suppressed by a short-acting neuromuscular blocking agent (eg, succinylcholine, 0.5-1 mg/kg IV). It should be emphasized that succinylcholine does not obliterate central nervous system manifestations of seizure activity. Rapid tracheal intubation and mechanical ventilation can prevent pulmonary aspiration of gastric contents and facilitate hyperventilation therapy. 

Clancy M, Halford S, Walls R, Murphy M. In patients with head injuries who undergo rapid sequence intubation using succinylcholine, does pretreatment with a competitive neuromuscular blocking agent improve outcome A hterature review. Emerg Med J 2001 18(5) 373-5. 

Botulinum-A toxin, dantrolene, ketoconazole, neuromuscular blocking agents, polymyxins, succinylcholine (suxamethonium), tizanidine... 

Succinylcholine, a depolarizing neuromuscular blocking agent (0.3 to 1.1 mg/kg IV over 10 to 30 seconds), is used to induce skeletal muscle relaxation to facilitate intubation, ventilation, or orthopedic manipulations and to lessen muscular contraction in convulsions induced by physicians. A peripheral nerve stimulator may be used to monitor effects and degree of blockade. 

Electroconvulsive therapy (ECT) of psychiatric disorders occasionally is complicated by trauma to the patient the seizures induced may cause dislocations or fractures. Inasmuch as the rtmscu-lar component of the convulsion is not essential for benefit from the procedure, neuromuscular blocking agents and thiopental are employed. Succinylcholine or mivacurium is used most often because of the brevity of relaxation. 

If the patient is not fuiiy relaxed (eg, if the jaw is not flaccid or neck mobility Is restricted), induce neuromuscular paralysis with succinyl-choline (1-1.5 mg/kg intravenously [IV]), rocuronium (0.6-1.2 mg/kg IV) or pancuronium (0.1 mg/kg IV), or another neuromuscular blocking agent (see p 472). Caution In children, succinylcholine may induce excessive vagal tone, resulting in bradycardia or asystole. Patients with digitalis intoxication (see p 155) may have a similar response to succinylcholine. Pretreat with atropine (0.01 mg/kg IV),... 

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