Design

Specialized DOC program.

Setting

Specialized DOC program and university hospitals.

Participants

Participants (N=85) diagnosed with DOC.

Interventions

Not applicable.

Main Outcome Measures

We prospectively assessed consciousness with the Coma Recovery Scale–Revised (CRS-R). Responses during baseline, non-noxious, and noxious stimulations were scored with the NCS-R and CRS-R oromotor and motor subscales.

Results

CRS-R total scores correlated with NCS-R total scores and subscores. CRS-R motor subscores correlated with NCS-R total scores and motor subscores, and CRS-R oromotor subscores correlated with NCS-R total scores as well as verbal and facial expression subscores. There was a difference between unresponsive wakefulness syndrome and minimally conscious state in the proportion of grimacing and/or crying participants during noxious conditions. We replicated previous findings on psychometric properties of the scale but found a different score as the best threshold for nociception.

Conclusions

We report a strong relation between the responsiveness to nociception and the level of consciousness. The NCS-R seems to be a valuable tool for assessing nociception in an efficient manner, but additional studies are needed to allow recommendations for clinical assessment of subjective pain experience.