Pain control is an important objective for healthcare teams, in the operating theatre during general anaesthesia, in intensive care as well as in situations where patients are unable to communicate the intensity of the pain they feel, for example in unconscious patients, those who are disabled, or in neonatology and paediatrics.

In these situations, conventional pain assessment methods (visual scale, verbal scale, etc.) cannot be used. Indirect methods based on haemodynamic parameters such as heart rate, blood pressure and a few other clinical signs (sweating, tears, etc.) can be used but are not considered reliable.

Numerous studies show that analysis of respiratory sinus arrhythmia (variation in heart rate influenced by normal breathing) opens a window onto the autonomic nervous system (ANS), which is itself influenced by nociception.

MDoloris has developed the ANI (Analgesia Nociception Index) which measures heart rate variability: an alternative technology to empirical methods. Heart rate variability is higher when parasympathetic activity dominates sympathetic activity. Its aim is to better manage pain treatment and optimise the doses of analgesics administered.

ANI technology, as well as being a pain monitoring system, is a system for monitoring parasympathetic activity, which provides information about the body’s state of comfort or discomfort.

The ANI V2 monitor enables the parasympathetic tone to be monitored by directly measuring the ANS: Autonomic Nervous System, which uses the cardiac signal and Heart Rate Variability (HRV).