BACKGROUND: Because both dyspnea and pain have common features from a clinical and physiologic point of view, we hypothesized that stellate ganglion irradiation by using a linear polarized near-infrared ray device, which is often used for pain management, might be applicable for dyspnea relief. To evaluate the use of stellate ganglion irradiation as a novel noninvasive treatment for dyspnea, we investigated the influence of stellate ganglion irradiation on dyspnea. METHODS: Perceptions of dyspnea were examined with or without stellate ganglion irradiation in 28 healthy adults. The sensation of breathing difficulty was induced by a two-way non-rebreathing valves with linear inspiratory resistance (R) of 0, 10, 20, and 30 cm H 2 O/L/s. Dyspnea was evaluated with the modified Borg scale to determine subjects' discomfort level. Stellate ganglion irradiation was performed by intermittent irradiation near the bilateral stellate ganglion by using a linear polarized near-infrared ray device. RESULTS: There were significant changes from baseline at R ؍ 10 cm H 2 O/L/s (P ؍ .007), R ؍ 20 cm H 2 O/L/s (P ؍ .005), and R ؍ 30 cm H 2 O/L/s (P ؍ .009). For each resistive load, the mean dyspnea sensation score was lower with stellate ganglion irradiation compared with sham irradiation, with significant differences (P ؍ .003 at R ؍ 0 cm H 2 O/L/s; P < .001 at R ؍ 10, 20, 30 cm H 2 O/L/s). There was a significantly lower slope of the dyspnea response for the linear regression of the loads and Borg scores in the stellate ganglion irradiation versus sham treatment (P ؍ .003). CONCLUSIONS: Stellate ganglion irradiation significantly alleviated dyspnea induced by an external inspiratory load in healthy adults. Stellate ganglion irradiation might be an option to treat dyspnea in some cases. Further studies in individuals with diverse types of dyspnea and clinical settings are warranted.
