Can Pulsed Radiofrequency of the Occipital Nerves Cause Sedation? A New Perspective of Existing Knowledge.

Arvaniti, Chrysa; Madi, Alia Ibrahim; Kostopanagiotou, Georgia; Batistaki, Chrysanthi

Background Pulsed radiofrequency stimulation (PRF) of the greater and lesser occipital nerves (GON and LON) has neuromodulative and analgesic properties. Objectives The aim of this study was to investigate whether the PRF of the occipital nerves can cause sedation. Methods This is an observational case series study in Pain Management Unit of Attikon University Hospital. Patients suffering from primary headaches were scheduled for PRF of occipital nerves following a standardized protocol. The Bispectral Index device was applied and recorded every minute throughout the procedure. Results 22 patients were studied. BIS values were lowered in all but three patients during GON stimulation, and in all patients during LON stimulation. Values of decline compared to baseline ranged between 0 - 23 (median 8.5) for GON and 1 - 27 (median 14) for LON, with LON decline being significantly lower. Conclusions PRF at the occipital nerves led to mild sedation in all patients. Further studies are required to investigate this effect and clarify the exact mode of action of pulsed radiofrequency.