Experimentally induced pain and paresthesia respond differently to parameter changes of cuff-based compression in pain-free young individuals

Abstract

Neuropathic pain is a significant therapeutic challenge due to the co-occurrence with other neurological symptoms such as paresthesia. Human-based models e.g., cuff algometry, may provide a better understanding of the association between pain and paresthesia. This experiment aimed to characterize (psychophysically) pain and paresthesia evoked by stimuli of different temporal and intensity parameters and to demonstrate the reliability of experimental induction of these two symptoms using cuff algometry. Forty healthy participants were exposed to mechanical pressure stimuli at three intensities (100, 150, and 200mmHg) and three durations (90, 120, and 150s). Electrodermal activity (EDA) was continuously monitored, and participants rated pain and paresthesia in real-time using a computerized visual analog scale. General Linear Model analysis for paresthesia revealed significant differences among all durations (p<0.01), but not between all intensities as paresthesia did not increase from 150 to 200 mmHg (p>0.05). In contrast, for pain, significant differences were found across all pressure intensities (p<0.05) but not for all stimulus durations, as pain did not increase from 90 to 120, and from 120 to 150s (p>0.05). No interaction effects were observed for either symptom. EDA analysis showed no significant main or interaction effects. Intraclass correlation coefficients (ICCs) indicated that paresthesia and pain induction had moderate to good reliability across different durations and intensities (ICC: 0.52 - 0.90), while EDA showed poor to moderate reliability (ICC: 0.21 - 0.73). In conclusion, computer-based cuff algometry is an effective and reliable method to induce pain and paresthesia, allowing them to be assessed simultaneously. Furthermore, the results indicate that pain and paresthesia are characterized by different patterns, depending on pressure duration and intensity.