Effects of Acupuncture Stimulation to Cervical Sympathetic Trunk on Maximal Respiratory Mouth Pressure: A Randomized Crossover Study

The autonomic nerves in the lungs and the intercostal and phrenic nerves are important for respiratory movements. This study investigated the effects of electroacupuncture (EA) stimulation via the sympathetic nerve on maximal respiratory mouth pressure.This prospective, single-center, randomized crossover study was conducted in Teikyo Heisei University, Japan. The subjects were 17 healthy adults (15 men and 2 women), who were randomly assigned to untreated and EA groups in a crossover trial with a 2-week washout period. Initially, respiratory mouth pressure was tested in both groups. After 5 minutes of rest, either a 5-minute rest or an EA stimulus was delivered, followed by 5 minutes of rest. EA was delivered near the cervical ganglia at the level of the sixth cervical vertebra on the left side. The EA stimulus was set to 2 Hz, and the stimulation intensity was set to a level so that no pain would be felt by the volunteers. Nasal-skin temperature was measured during rest or EA stimulation. Thereafter, respiratory mouth pressure was tested again in both groups.The EA group had a significant reductions in nasal-skin temperature during the intervention and a significant increase in inspiratory and expiratory respiratory mouth pressure after the intervention, compared to the nonstimulated group.The 2-Hz EA stimulation via the sympathetic nerve activated the sympathetic nerves and suppressed respiratory mouth pressure weakness. Future studies are needed to evaluate EA's effectiveness for treating bronchial stenosis and respiratory weakness.