Neuromuscular blocking drug

When kaolin or aluminum is administered widi die lincosamides, die absorption of the lincosamide is decreased. When the lincosamides are administered with the neuromuscular blocking drag (drag diat are used as adjuncts to anesthetic drag diat cause paralysis of the respiratory system) die action of die neuromuscular blocking drug is enhanced, possibly leading to severe and profound respiratory depression. 

Bermejo, N. et al., Platelet serotonin is a mediator potentially involved in anaphylactic reaction to neuromuscular blocking drugs, Br. J. Anaesth., 70, 322, 1993. 

This topic tests your knowledge of the physics and physiology behind the use of neuromuscular blocking drugs (NMBDs). You will benefit from a clear idea in your mind about what each type of nerve stimulation pattern is attempting to demonstrate. 

Two precautions should be kept in mind Neuromuscular blocking drugs inhibit, concentration-dependently, all skeletal muscles including those necessary for respiration. If these muscles are paralyzed by these drugs artificial respiration must be applied since central or peripheral nerve stimulation, for example with analeptics are useless. Furthermore is it important to realize that the individual subjected to a efficient neuro-muscular blockade is fully conscious and aware of any pain although completely unable to express discomfort. 

The second group of neuromuscular blocking drugs are those of the depolarizing type. These compounds resemble the structure of two molecules of... 

While most of the muscle relaxants exert their predominant actions at the post-junctional nicotinic receptors, many also have variable pre-junctional effects. Although pre-junctional receptors have not been demonstrated there is putative evidence for their existence. The pre-junctional mechanisms are supposed to be responsible for the development of fade in response to tetanic or train-of-four (TOP) stimulation following administration of non-depolarising neuromuscular blocking drugs. 

Mirakhur RK. Newer neuromuscular blocking drugs An overview of their clinical pharmacology and therapeutic use. Drugs 1992 44 182-99. 

A specialized form of conscious sedation is occasionally required in the ICU, when patients are under severe stress and require mechanical ventilation for prolonged periods. In this situation, sedative-hypnotic drugs or low doses of intravenous anesthetics, neuromuscular blocking drugs, and dexmedetomidine may be combined. 

Structures of some isoquinoline neuromuscular blocking drugs. These agents are all nondepolarizing muscle relaxants. 

All of the neuromuscular blocking drugs are highly polar compounds and inactive orally they must be administered parenterally. 

Table 27-1. Some Properties of Neuromuscular Blocking Drugs. ...

Before the introduction of neuromuscular blocking drugs, profound skeletal muscle relaxation for intracavitary operations could be achieved only by producing levels of volatile (inhaled) anesthesia deep enough to produce profound depressant effects on the cardiovascular and respiratory systems. The adjunctive use of neuromuscular blocking drugs makes it possible to achieve adequate muscle relaxation for all types of surgical procedures without the cardiorespiratory depressant effects produced by deep anesthesia. 

Table 27-3 Effects of Neuromuscular Blocking Drugs on Other Tissues.

A novel cyclodextrin reversal drug, sugammadex, has been submitted for FDA approval. It can rapidly inactivate steroidal neuromuscular blocking drugs by forming an inactive complex, which is excreted in the urine. This process allows the practitioner to rapidly reverse even profound degrees of neuromuscular blockade produced by rocuronium and vecuronium at the end of the surgical procedure. 

In critically ill patients who have ventilatory failure from various causes (eg, severe bronchospasm, pneumonia, chronic obstructive airway disease), it may be necessary to control ventilation to provide adequate gas exchange and to prevent atelectasis. In the ICU, neuromuscular blocking drugs are frequently administered to reduce chest wall resistance (ie, improve thoracic compliance) and ineffective spontaneous ventilation in intubated patients. 

Neuromuscular blocking drugs (ie, succinylcholine) are occasionally used to attenuate the peripheral (motor) manifestations of convulsions associated with status epilepticus or local anesthetic toxicity. Although this approach is effective in eliminating the muscular manifestations of the seizures, it has no effect on the central processes because neuromuscular blocking drugs do not cross the blood-brain barrier. 

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