On the Effect of Neuromuscular Blocking Agents on the Central Nervous System

Abstract

Although investigations have been numerous, for the present, there is no universal opinion on the effect of neuromuscular blocking agents on the functions of the central nervous system. This is largely due to the fact that, according to clinical data, neuromuscular blocking agents on systemic administration do not induce marked central action. Therefore, the apparent effects, if any, are rather difficult to detect during clinical evaluation of neuromuscular blocking agents. Thus, while testing these drugs during operations, it should be taken into account that the patient receives many other drugs for premedication and anesthesia. This creates a certain background that may influence or mask the central action of a neuromuscular blocking agent. The interpretation of the data obtained is significantly hindered by different degrees of trauma involved in surgical interventions, total muscle paralysis, changes of the functional state of the visceral organs and systems, disturbances of water and electrolyte balance, the volume of the blood loss, and many other factors which can modify the function of the central nervous system. Certain difficulties are involved in the evaluation of experimental data, too. These are related to the ability of neuromuscular blocking agents to induce not only direct, but also indirect central action. Thus, for instance, total muscle paralysis induced by neuromuscular blocking agents changes the afferent proprioceptive firing, which significantly affects the activity of cerebral neurons.