Quantifying virtual reality pain modulation in healthy volunteers: A randomized, crossover study

Study objective: Virtual reality (VR) is an emerging tool to reduce pain and anxiety during procedures. Although VR's clinical benefits are reported, biometric data quantifying VR's effect on pain tolerance is lacking. We used time-lapse, subjective, and biometric data to evaluate VR's effect on modulating pain.

Design: Randomized, controlled crossover within-subject clinical trial.

Setting: This study was conducted in the Chariot Lab at Lucile Packard Children's Hospital and outdoors at Stanford University School of Medicine.

Patients: 156 healthy volunteers were included.

Interventions: Participants underwent pain-inducing ice immersions while connected to biometric sensors. Participants were randomized to immerse their dominant or non-dominant hand with VR or control (no VR) for one immersion, and then crossed-over to the other hand for the second immersion. We instructed participants to submerge their hand until they reached their pain tolerance or until four minutes elapsed.

Measurements: Outcomes included ice immersion duration, perceived pain scores, and skin conductance response density (SCRD), a marker of sympathetic arousal. We used survival analysis and mixed effects models to compare measurements with and without VR.

Main results: 153 participants were included in the analysis. Participants with VR were 64% less likely to remove their hands from the ice bath throughout the immersion's duration compared to control (P < 0.001). Participants with VR reported significantly lower pain scores after controlling for dominant hand treatment assignment, VR vs. no VR treatment order, and gender (P < 0.001). SCRD increased as time progressed for both VR and control groups (P = 0.047 combined), with no significant mean group differences.

Conclusions: Participants with VR were more likely to survive the 4-min ice bath challenge longer and with lower levels of pain perception, supporting VR's effectiveness as a distraction tool during painful procedures. We observed no differences in sympathetic response when comparing VR to no VR.