Phrenic nerve stimulation (diaphragm pacing) in chronic singultus

The authors implanted a diaphragm pacer in a 71-year-old man who had suffered for two years from continuous hiccup of unknown cause with resulting insomnia. Preoperative transcutaneous stimulation of the phrenic nerves in the neck resulted in diaphragm contractions but did not affect his hiccup. Postoperatively, the patient was free of symptoms for two weeks. Electrophrenic stimulation was then initiated and after three days his hiccup disappeared again. After a ten day period without stimulation his hiccup recurred. For ten months the patient has suffered from hiccup only in the day time during which time he has also used the pacer. With a few exceptions he has been free of symptoms and without pacing during the night, which enables him to sleep normally. The effect of phrenic nerve stimulation on hiccup could be due to interference with the abnormal activation of the phrenic nerve, whatever its cause.