The Food and Drug Administration (FDA) has cleared Primary Relief, a percutaneous electrical neurostimulation (PENS) device, to treat pain following cardiac surgery.

Primary Relief is a wearable, battery-operated device that delivers electrical pulses to branches of the cranial nerves on the ear through a wire assembly and stimulation needles. Once activated, the device administers periodic low level electrical pulses over 72 hours.

The approval was based on a single-center, double arm, randomized, prospective study that evaluated the effectiveness of the Primary Relief device in 60 patients who underwent cardiac surgery. Results showed patients who received the Primary Relief device had reduced pain scores compared with those who received a placebo device. 

Additionally, use of the Primary Relief device reduced the requirements for analgesics after surgery. Compared with the control group, patients who received Primary Relief required only one-third of the mean dosage of fentanyl in the postoperative period. In the Primary Relief group, only 4 patients required diclofenac as a second rescue analgesic vs 19 patients in the control group.

“This ground-breaking device allows for significant pain relief without the use of narcotics,” said DyAnsys Chief Executive Srini Nageshwar. “By reducing or avoiding the use of opioids after surgery, the risk of addiction is reduced. We look forward to connecting with physicians and patients to make this option available after cardiac surgery among other applications.”

In addition to post cardiac surgery pain, the device recently received FDA clearance for symptomatic relief of postoperative pain following caesarean section (C-section) delivery.


FDA clears DyAnsys neurostimulation device primary relief to treat post-cardiac surgery pain. News release. DyAnsys, Inc. Accessed September 22, 2022.