Children with vagus nerve stimulation systems receive pre-programmed stimulation 24 hours per day. A unique feature of this therapy is the hand-held magnet, which the patient or family member can use at the onset of a seizure to activate the device to deliver an additional stimulus. The battery replacement surgery takes approximately one hour and can be carried out under local anesthesia. All of the side effects occur during stimulation and are directly related to the amount of output current. This is considered the child's dosage.
Most patients accommodate well.
The most serious complication from vagus nerve stimulation is the possibility of temporary or permanent vocal cord paralysis. This usually is a surgical complication and not directly associated with stimulation. Randomized controlled studies indicate that vagus nerve stimulation offers seizure control that lasts over time. The most recent studies on efficacy indicate that 24 months after implantation, patients are seeing a 40-60 percent reduction in seizure frequency. Paul Grabb, MD, a pediatric neurosurgeon, implanted all 17 children at Children's Hospital.