Vagus Nerve Stimulation (VNS) involves surgically placing a device that sends mild electrical pulses to the brain via the vagus nerve in the neck. This therapy is used to reduce the frequency of seizures in patients with drug-resistant epilepsy. VNS is also approved to treat certain cases of severe depression and can be used as a rehabilitation aid following an ischemic stroke. While the total time commitment for a patient spans several hours, the actual implantation procedure is relatively brief.
Preparing for the Operation
Preparation begins with arrival at the hospital. After checking in, the patient meets with the nursing staff and the anesthesiologist for a pre-operative assessment. This assessment confirms the patient’s medical history, reviews medications, and answers any last-minute questions.
The most significant step is the administration of general anesthesia, ensuring the patient is unconscious and pain-free. The surgical team then positions the patient, typically with the head turned right to expose the left side of the neck. Final preparation involves sterilizing the skin and marking the two incision sites: one on the chest and one on the neck.
The VNS Implantation Duration
The actual VNS implantation procedure typically takes between 45 to 90 minutes. The process begins with the surgeon making a small horizontal incision on the lower left side of the neck to access the vagus nerve. The surgeon isolates the nerve and carefully wraps the electrode portion of the lead wire around it.
A second incision is made on the upper left chest to create a pocket for the pulse generator. The lead wire is tunneled under the skin to connect the electrodes to the generator. Variability in the procedure’s length depends on factors such as the patient’s anatomy, prior scar tissue, and the surgeon’s experience level.
Immediate Post-Surgical Monitoring
Once the surgical wounds are closed, the patient is transferred to the Post-Anesthesia Care Unit (PACU). This monitoring phase typically lasts between two and four hours. The primary goal is to ensure the patient safely wakes up from anesthesia and that their condition is stable.
Nurses continuously monitor the patient’s vital signs, including heart rate, blood pressure, oxygen saturation, and respiratory function. They also manage any post-operative pain or nausea. Before discharge, the patient must meet specific criteria, such as being fully awake, having stable vital signs, and being able to tolerate oral fluids.
The Timing of Device Activation
The VNS device is not turned on immediately following the surgery. The generator is left inactive to allow for post-operative healing and to let swelling subside. This delayed activation prevents discomfort and potential side effects if the nerve were stimulated while the tissue is inflamed.
The stimulator is programmed and activated by a neurologist or clinician during a follow-up appointment, generally scheduled two to four weeks after implantation. Activation is performed externally using a programming wand that communicates with the generator through the skin. The clinician starts the device at a low electrical output and gradually adjusts the settings to optimize the therapeutic effect.