Cortical Components

• Unconsciousness refers to the lack of awareness of the outside world. It is this component where the patient is asleep during general anaesthesia. 
• Amnesia refers to the patient’s loss of memory of the operation. It is imperative that the patient does not have any memory recollections of the events during the operation.

Subcortical Components

• Antinociception refers to inhibition of the nociceptive processing in the nervous system. Analgesia is the treatment to provide antinociception.
• Immobility refers to the patient’s lack of motion. Complete immobility should be ensured to maintain a stable surgical field.
• Autonomic stability refers to the absence of excessive hemodynamic responses.

Entropy measurement may be used as an aid in monitoring the effects of certain anaesthetic agents. In adults, it may help the user titrate anaesthetic drugs according to the individual needs and may be associated with a reduction of aneasthetic use and faster emergence from anaesthesia. Entropy monitoring is based on data acquisition and processing of raw electroencephalographic signals (State Entropy = SE) and frontal electromyographic signals (Response Entropy = RE).

The device that produces this measurement is the E-ENTROPY Module.

See more publications from Entropy Publication Reference List.

Published literature suggests that NMT measurements may help the clinician optimize dosage during anaesthesia¹ and optimize recovery and prevention of respiratory complications in PACU.^1,2,3,4

1. Residual neuromuscolar block:lesson unlearned.Part II Methods to reduce the risk of residual weakness .Soriin Brull MD, Glenn Murphy MD. Anestehsia-Analgesia July 2010 Volume 111 Number 1.
2. Monitoring and Pharmacologic Reversal of a nondepolarizing neuromuscolar blockade should be routine. Ronald Miller MD, Theresa Ward BSN, RN . Anestehsia-Analgesia July 2010 Volume 111 Number 1.
3. Evidence –Based management of neuromuscolar block. Mogensen MD DMSc FRCA, Casper Claudio MD PhD. Anestehsia-Analgesia July 2010 Volume 111 Number 1.
4. Neuromuscolar Monitoring:what evidence do we need to be convinced? Donati , PhD, MD. Anestehsia-Analgesia July 2010 Volume 111 Number 1.

The Surgical Pleth Index (SPI)* is a parameter that reacts to hemodynamic responses caused by surgical stimuli and analgesic medications. Published literature suggests that SPI guided anesthesia may result lower remifentanil consumption¹, more stable haemodynamics¹ and lower incidence of unwanted events¹.

SPI is an algorithm that uses two components of the GE plethysmographic signal obtained from E-PSM(P), E-PRESTN and E-RESTN Modules. SPI should be measured using specified GE SPO2 finger sensors only.

See more publications from SPI Publication Reference List.

1. Chen et al.: Comparison of Surgical Stress Index-guided analgesia with standard clinical practice during routine general anaesthesia Anaesthesiology, V 112, No.5 2010.

The configurable AoA split screen of GE’s CARESCAPE modular monitors, combined with hemodynamic parameters and respiratory gas measurements, provides a comprehensive visual view of patient’s status.

In the unique AoA split screen, you will find the BalanceView, which combines and plots Surgical Pleth Index (SPI) and SE values (one component of the Entropy measurement). This view helps the clinician monitor the effects of the analgesic and anesthetic pharmaceuticals during general anesthesia.