ANI Monitor V1 - Continouous analgesia monitoring system
MD/PRD/IN16.ANIV1 V.10 – 29 SEP 2021
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General safety sign
Manufa
Manufacturing Date
Protective earth;
protective ground
2
ANI Monitor V1 presentation
ANI (Analgesia Nociception Index) is an online continuous measurement of the
parasympathetic tone (p
), which is a part of the autonomous system (ANS). Each respiratory
cycle induces in the ANS a temporary fall of p
tone, which can be measured on the
normalized RR series by the resulting amplitude of “respiratory pattern”.
Rapid p
tone variations express themselves directly on the sinus mode by way of the vagal
nerve issued from the brain stem, where it is connected with afferent stimuli from bronchial
stretch sensors. Each respiratory cycle (spontaneous or in positive pressure) gives an
information about the instantaneous p
tone by measuring the amplitude of the associated
sharp decrease in the normalized RR series (respiratory pattern).
The RR series is established by means of an electrocardiogram, by detecting the R waves and
measuring the time interval between adjacent R waves. After normalization and resampling,
the p
compound of the RR series is obtained by filtering in order to keep only high
frequency signals in the RR series. The surface delineated by successive respiratory patterns
is directly related to the instantaneous p
tone: the more p
tone there is, the bigger the
surface.
To note: ANI measurement cannot be interpreted in the following situations:
•
arrythmia
•
apnoea (e.g. apnoea induced by anesthesia)
•
respiratory frequency of less than 9 cycles/min
