The US Food and Drug Administration has approved the NeuRx DPS RA/4 Respiratory Stimulation System, an implantable electronic device that stimulates the diaphragm and allows certain spinal cord injury patients to breathe for at least four hours a day without a mechanical ventilator.

Spinal cord injuries can cause paralysis, which can effect the muscles of the chest and abdomen, including the diaphragm-the lower abdominal muscle essential for breathing. Normally, a person inhales when the diaphragm contracts and the lungs expand with air-a person exhales when the diaphragm relaxes and the air flows back out of the lungs.

Daniel G. Schultz, M.D., director of the FDA's Center for Devices and Radiological Health explains that the NeuRx RA/4 does not cure paralysis of the diaphragm, allowing patients to be free from a mechanical ventilator for at least four hours a day may enhance their quality of life. Patients with severe spinal cord injuries who cannot control their diaphragms often need mechanical ventilation to help them breathe. This usually requires a full-time connection to a ventilation machine. The NeuRx DPS RA/4 uses four electrodes implanted in the muscle of the diaphragm to electronically stimulate contraction; this stimulation allows the patient to inhale.

The US FDA approved the distribution of this device under a Humanitarian Device Exemption, an approval process for devices intended to treat or diagnose conditions that affect fewer than 4,000 people per year. In a multi-centre trial, the device has been demonstrated to be safe and to have probable benefit to the patient by allowing at least four hours per day of freedom from a mechanical ventilator. NeuRx DPS RA/4 is manufactured by Synapse Biomedical of Cleveland, Ohio