Management Strategies for Side Effects Associated with Initiation of Vagus Nerve Stimulation
Abstract number :
3.209
Submission category :
Year :
2001
Submission ID :
144
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
A.A. Cohen-Gadol, MD, Neurosurgery, Mayo Clinic, Rochester, MN; J.W. Britton, MD, Neurology, Mayo Clinic, Rochester, MN; R.W. Marsh, MD, Neurosurgery, Mayo Clinic, Rochester, MN; F.B. Meyer, MD, Neurosurgery, Mayo Clinic, Rochester, MN
RATIONALE: Vagus nerve stimulation (VNS) has received acceptance as a treatment modality for medically refractory partial seizures. There were significant side effects during initiation of VNS in four patients. We present these cases to illustrate how the significant problems associated with VNS initiation were managed, allowing us to continue this treatment.
METHODS: The medical records of 4/85 (4.7%) patients implanted with the NeuroCybernetic Prosthesis pulse generator who experienced significant adverse effects upon initiation were reviewed.
RESULTS: The prosthesis was successfully implanted in all four patients. Patient [pound] 1 experienced significant bradycardia (down to 30 beats/min) during the lead test. Three weeks later, stimulation was initiated at an output current = 0.25 milliampere and pulse width = 250 microsecond, while monitoring the EKG continuously with a code cart and parental atropine on hand. The stimulation parameters have since been increased without complications.
Patient [pound] 2 experienced severe dysphagia following initiation of stimulation. Aspiration was demonstrated with a video swallow study. Deactivating the stimulator during meals by taping a magnet over the generator has prevented aspiration in the two years since implantation.
Patient [pound] 3 experienced wretching the next day after the device was set at the lowest settings. Her device was turned off for two weeks after which the stimulation was initiated again at an output current = 0.5 milliampere and pulse width = 250 microsecond and subsequently increased without incident.
Patient [pound] 4 also experienced wretching when the device was first turned on. She was started on Ondansetron 4mg t.i.d. and for 24 hours and tolerated an output current = 0.25 milliamperes, frequency = 20 Hz, and pulse width = 130 microsecond the next day. She was then tapered off her Ondansetron over one week, and the stimulator parameters were increased to output current = 1.25 milliampere, pulse width = 250 microsecond, and frequency = 20 Hz.
CONCLUSIONS: In some cases, severe side effects develop during VNS initiation which can threaten our ability to use this treatment modality. Slow titration of stimulation levels and adjunctive symptomatic treatment may be necessary in order to allow the use of this form of treatment after costly implantation.
Support: No Funding Required