Device maker, Medtronic, just issued a warning to consumers concerning a problem with its Model 37751 Rechargers that work with its deep-brain stimulation devices.
According to Medtronic, the Rechargers may become unresponsive and unable to fully recharge the neurostimulator until they are reset. In some cases, consumers have reported that Rechargers are not functional and make a bleep noise every five seconds while displaying a blank display screen, what is known as an unresponsive error state, according to Medtronic’s letter, MassDevice wrote.
Medtronic wrote that all Rechargers manufactured since November 2014 are susceptible to this “error state.” According to MassDevice, the error has been reported for two percent of Rechargers manufactured since that date and .2 percent that were sold prior to that date. The Rechargers are used by patients who have been implanted with a neurostimulator for deep brain stimulation therapy, according to MassDevice.
The defective Rechargers do not recharge the neurostimulator until the Recharger is reset, according to Medtronic, wrote MassDevice. When the neurostimulator battery fully depletes, patients may lose their therapy, enabling symptoms to return. In fact, some patients who receive deep brain stimulation therapy—patients undergoing treatment for Parkinson’s disease, for example—may experience significant, life-threatening injuries, such as akinetic crisis, sometimes death, should their stimulation therapy cease. Patients treated for epilepsy may suffer status epilepticus.
According to Medtronic, no reports of any life-threatening injuries or deaths have been received over this issue, MassDevice reported.
Medtronic recommended that, to prevent these issues, that the Recharger must be plugged into the AC power supply, aligning the white triangles, before recharging the neurostimulator; the Recharger should remain connected until the recharging session completes. Should the Recharger already be unresponsive, Medtronic suggested physicians assist patients with a Recharger reset. The AC power supply does not need to be plugged into a power outlet if the Recharger is charged
Medtronic advised doctors to advise patients about the malfunctioning Rechargers and to discuss the interim correction as Medtronic researches a more permanent solution.
Medtronic’s Urgent Field Safety Notice indicated that the Medtronic Model 37751 Recharger that is included in the Model 37651 Charging System are involved. The Model 37751 Rechargers are sold in kit Model 37651 Charging System for Deep Brain Stimulation (DBS). The recharger is used by DBS patients implanted with a Medtronic ActivaTM RC (Model 37612) implantable neurostimulator.
All Rechargers manufactured since November 2014—indicated by serial numbers beginning with “NKA4” or “NKU4”—are more susceptible to this error state.
Should the implanted neurostimulator battery be allowed to remain fully depleted, it may over discharge, which will cause a permanent reduction in battery capacity and the need to recharge more frequently in the future.