The cortical components of anesthesia refer to the effects of the anesthetics in the brain, particularly in the cerebral cortex, where cognitive processes take place. These components are best monitored by cortical measures, such as the Entropy available in the S/5 Entropy Module.

The hypnotic and amnestic effects of anesthetics actually are two separate phenomena. Amnesia usually occurs at lower drug concentrations than loss of consciousness. Movement during anesthesia may be the result of a spinal reflex – not necessarily a sign of consciousness.

• S/5 Entropy Module

Antinociception refers to inhibition of the nociceptive processing in the nervous system, achieved by adequate analgesia. The role of antinociception is crucial; it makes surgical operations possible, and it reduces their immediate and long-term negative consequences.

Immobility and relaxation of the patient can be achieved either by certain anesthetic agents or by neuromuscular blockers. Whenever the latter are used, the amount of block should be monitored, e.g. by GE Healthcare NMT measurement.

Autonomic stability fulfills the picture, ensuring minimal hemodynamic variations during the procedure.

• GE Healthcare NMT measurement

See the Adequacy of Anesthesia and Relaxation issues of Clinical Window Web Journal.

See also the list of Published Entropy Studies (PDF 132 KB, updated August 2004)

• List of Published Entropy Studies