Treatment of asthmatic bronchoconstriction by percutaneous low voltage vagal nerve stimulation: case report.

Abstract

Background: A 34 year old Hispanic male patient presented himself in the emergency room with recurring severe asthma that was unresponsive to b-adrenergic and steroid therapy. Spirometry demonstrated significant airflow obstruction. Objective: We sought to test the ability of low voltage vagus nerve stimulation to induce bronchodilation and improve airflow.Method: A percutaneous electrode was inserted into the patient’s neck and positioned to lie in the vicinity of the carotid sheath. Following placement, stimulation was administered and the signal amplitude slowly increased until muscle twitching or discomfort was reported by the patient then reduced to a comfortable level. Results: Within minutes of stimulation, the patient reported reduced dyspnea that was confirmed by spirometry fifteen minutes later (FEV1 increased from 2.70 L to 3.18 L). The FEV1 remained elevated during the 180min treatment (3.29 ± 0.04 L) and at 30min post stimulation (3.36 L). The FEV1 then decreased to 2.84 L 60min after stimulation ended. Conclusion: This finding indicates that low voltage vagus nerve stimulation could be a useful critical care treatment to alleviate smooth muscle bronchoconstriction and offer a new therapeutic approach to the treatment of acute asthma.