Monitoring the nociception level: a multi-parameter approach

Abstract

The aim of the present study was to develop and validate an objective index for nociception level (NoL) of patients under general anesthesia, based on a combination of multiple physiological parameters. Twenty-five patients scheduled for elective surgery were enrolled. For clinical reference of NoL, the combined index of stimulus and analgesia was defined as a composite of the surgical stimulus level and a scaled effect-site concentration of opioid. The physiological parameters heart rate, heart rate variability (0.15-0.4 Hz band power), plethysmograph wave amplitude, skin conductance level, number of skin conductance fluctuations, and their time derivatives, were extracted. Two techniques to incorporate these parameters into a single index representing the NoL have been proposed: NoLlinear, based on an ordinary linear regression, and NoLnon-linear, based on a non-linear Random Forest regression. NoLlinear and NoLnon-linear significantly increased after moderate to severe noxious stimuli (Wilcoxon rank test, p < 0.01), while the individual parameters only partially responded. Receiver operating curve analysis showed that NoL index based on both techniques better discriminated noxious and non-noxious surgical events [area under curve (AUC) = 0.97] compared with individual parameters (AUC = 0.56-0.74). NoLnon-linear better ranked the level of nociception compared with NoLlinear (R = 0.88 vs. 0.77, p < 0.01). These results demonstrate the superiority of multi-parametric approach over any individual parameter in the evaluation of nociceptive response. In addition, advanced non-linear technique may have an advantage over ordinary linear regression for computing NoL index. Further research will define the usability of the NoL index as a clinical tool to assess the level of nociception during general anesthesia.

Automatic Pain Recognition from Video and Biomedical Signals

“…The linear combination of parameters significantly differentiated not only between pain and no pain, but also between all levels of pain (P < .001 to .02). Similarly Ben-Israel et al [18] developed and validated an index for nociception levels of patients under general anesthesia. The combination of the physiological parameters heart rate (HR), heart rate variability (HRV), PPG wave amplitude, GSR level, and GSR fluctuations outperformed any individual parameter in the evaluation of the nociceptive response.…”

Changes in Sleep Architecture under Sustained Pain in Adult Male Rats Subjected to Neonatal Short-Lasting Local Inflammatory Insult

“…These include the heart rate, HRV at 0.15-to 0.4-Hz band power, photoplethysmography wave amplitude, skin conductance level, and derivatives [43] , which all represent the activity of the sympathetic nervous system. A systematic review demonstrated an increase in sympathetic activity and a decrease in parasympathetic activity during experimentally induced pain in healthy adults based on HRV measurements [44] .…”

Comparison of the qCON and qNOX indices for the assessment of unconsciousness level and noxious stimulation response during surgery

“…However, increases in sympathetic activity can be caused by other factors not related to pain. Combinations of previous methods have also been described as potential indicators of nociceptive response as described by Schneider [14] or Ben-Israel [15]. Changes in pupil size [16,17] or other HRV derived parameters studying parasympathetic activity [18] in response to opioid concentrations or noxious stimulation have also been proposed as methods to assess the level of analgesia in surgical patients.…”