Neuromuscular blockade

R = / -C H ), in low doses, exhibits the former behavior and is used primarily as an extradural agent in obstetrics. The lowest effective extradural concentration of etidocaine (21, X = CH, R = R = 2H, R = / -C H ), however, shows both adequate sensory and profound motor blockade so that it is useful in surgical situations where maximum neuromuscular blockade is necessary. In an isolated nerve preparation, bupivacaine blocks unmyelinated C fibers which are mainly responsible for pain perception at a much greater extent than the myelinated A fibers which carry motor impulses. It is postulated that absorption of bupivacaine by the vasculature at the site of injection, combined with the slow diffusion of this agent, results in an insufficient amount of the drug penetrating the large A fibers to cause motor conduction blockade. Clinically, motor block can be observed in some procedures. 

Neurotoxicity (damage to the nervous system by a toxic substance) may also be seen with the administration of the aminoglycosides. Signs and symptoms of neurotoxicity include numbness, skin tingling, circum-oral (around the mouth) paresthesia, peripheral paresthesia, tremors, muscle twitching, convulsions, muscle weakness, and neuromuscular blockade (acute muscular paralysis and apnea). 

When an aminoglycoside is being administered, it is important to monitor the patient s respiratory rate because neuromuscular blockade has been reported with the administration of these dragp. The nurse reports any changes in the respiratory rate or rhythm to the primary health care provider because immediate treatment may be necessary. 

Neuromuscular blockade or respiratory paralysis may occur after administration of the aminoglycosides Therefore, it is extremely important that any symptoms of respiratory difficulty be reported immediately. If neuromuscular blockade occurs, it may be reversed by the administration of calcium salts but mechanical ventilation may be required. 

Paralysis usually is reserved for cases in whom sedation alone does not improve the effectiveness of mechanical ventilation. Neuromuscular blockers may lead to prolonged skeletal muscle weakness and should be avoided if possible. Patients requiring neuromuscular blockade are to be monitored and intermittent boluses should be utilized. 

Skeletal muscle Phrenic nerve/diaphragm Neuromuscular blockade... 

A single, supra-maximal stimulus is applied prior to neuromuscular blockade as a control. The diminution in twitch height and disappearance of the twitch correlates crudely with depth of neuromuscular block. 

A post-tetanic count is used predominantly where neuromuscular blockade is so deep that there are no visible twitches on TOF. The post-tetanic twitch count can help to estimate the likely time to recovery of the TOF twitches in these situations. The meaning of the count is drug specific. 

Neuromuscular Nicotinic receptors are responsible for transmission at the neuromuscular junction. While briefly causing stimulation, this phase is rapidly obscured by desensitization and neuromuscular blockade. Thus, nicotine has muscle-relaxant effects. 

Maksymowich, A.B., Reinhard, M., Malizano, C.J., Goodnough, M.C. and Johnson, E.C., Pure botulinum nerurotoxin is absorbed from the stomach and small intestine and products neuromuscular blockade. Infect. Immun., 67, 4708-4712, 1999. 

Neuromuscular blocking agents Do not use flumazenil until the effects of neuromuscular blockade have been fully reversed. 

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

Neuromuscular blockers Magnes um sulfate potentiates the neuromuscular blockade produced by neuromuscular blocking agents. 

Reversal of neuromuscular blockade Adults and children, 0.2 mg for each 1 mg neostigmine or 5 mg pyridostigmine. Administer IV simultaneously. 

Neuromuscular blockade Neurotoxicity can occur. Aminoglycosides may aggravate muscle weakness because of a potential curare-like effect on the neuromuscular junction. 

Neuromuscular blockade A partial neuromuscular blockade was demonstrated after large IV doses of capreomycin. This action was enhanced by ether anesthesia (as has been reported for neomycin) and was antagonized by neostigmine. 

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