Models for Nociception Stimulation and Memory Effects in Awake and Aware Healthy Individuals

Abstract

A device and methodology for non-invasive for detecting nociception stimulation have been developed. The proposed method and models have been validated on healthy volunteers.

Pain Detection with Bioimpedance Methodology from 3-Dimensional Exploration of Nociception in a Postoperative Observational Trial

“…In this particular case, the essential benefit of the ANSPEC-PRO device is that it allows a customizable input signal to the system under observation. In the particular studies case, the ANSPEC-PRO sends a composed multisine with optimal crest factor for optimal extraction of dynamic process information for identification purpose of a process model [13]. MEDSTORM, by contrast, has a single sine input at a single frequency, and the recorded signal back from the skin impedance is not processed as a function of frequency (due to its single point data) but in the time domain, using a moving window averaged amplitude correlated with the pain and awareness in the patient.…”

“…The diffusion of sodium/potassium ions changes the typical extracellular concentration, resulting in a negative charged extracellular fluid, so an action potential can be seen as variations of the electrical impedance of the tissue over the nociception pathway. The methodology for the prototype development and measurements are detailed in [13]. The measurement requires three-point electrodes applied on the palmar skin, as illustrated in Figure 2.…”

“…Although several commercially devices [2,8,9], as well as newly researched principles [10,11], are currently available and clinically evaluated in many trials, no monitor is widely and routinely used for analgesia assessment [12]. Hence, what differentiates Anspec-pro from the other available devices is the mathematical formalism for parametric modelling of time-frequency variations of skin impedance values [13]. Already developed methods show that changes in specific frequency ranges have the ability to characterize the cortical activity (e.g., gamma frequencies of EEG signal by the dimensionless index, WAV CNS [14,15]) or the parasympathetic nervous system (e.g., high-frequency heart rate variability index [16]).…”

An Open Source Patient Simulator for Design and Evaluation of Computer Based Multiple Drug Dosing Control for Anesthetic and Hemodynamic Variables

“…When surgical stimulation is present in the overall system, a nociceptor stimulation occurs. A recently developed method, device and model has been presented in [50], based on a physiological model of pain using fractional order tools reviewed in [51]. A simplified model of the nociceptor pathway is described by the following transfer function model:…”

“…Another feature contributed by the authors is the surgical stimulation nociceptor effect model, as experimentally identified and reported in [50]. The signal is added as a disturbance to the output of the PKPD model of Propofol and Remifentanil.…”