Description of Interstim Formal Lead and Generator Implant Peri-op Instructions
InterStim therapy is a pacemaker for the bladder used to reestablish appropriate nueromodulation of the bladder. The device works by using a stimulator device in the buttocks to stimulate the S3 nerve root in the back. This is the primary nerve root for bladder function. Stimulating the S3 nerve root with the InterStim device can result in a dramatic decrease in frequency, urgency and urge incontinence. InterStim therapy can also improve bladder emptying and result in decreasing post void residuals and therefore decreasing urinary tract infections and the other complications of incomplete bladder emptying. InterStim therapy can also be used to treat interstitial cystitis and pelvic pain. Outcomes for interstitial cystitis and pelvic pain are not as predictable as outcomes for frequency, urgency and urge incontinence.
For patients with significant symptoms of frequency, urgency, and urge incontinence who have tried anticholinergic medications but are not getting satisfactory results or cannot tolerate these medications InterStim therapy is an excellent choice. The two-step process of implanting an InterStim device requires a significant amount of time and energy on the part of the patient. The two steps include a simple test stimulation in the office or surgery center to gauge whether the patient is appropriate for InterStim therapy followed by subsequent implantation of the InterStim leads and the InterStim generator.
If you are scheduled to undergo Interstim Formal Lead and Generator Implant:
- Possible risks of Interstim Implant:
After this type of procedure a small risk of infection exists. You should receive antibiotics to begin taking the day before or the day of the procedure.
The first step for InterStim therapy is a simple test stimulation in the office or in the surgery center with IV sedation. Tiny wires are implanted into the small of the back near the S3 nerve and these tiny wires are connected to a generator box worn on the hip. The patient wears this box and these tiny wires over the ensuing week and tests one side and then the other for improvements in voiding symptoms. The wires are easily removed in the office and the results can be reviewed to determine if the patient should proceed to the next step. Sometimes only one test wire is placed. In this situation you will simply stimulate this single wire for the entire testing period.
The second step in InterStim therapy is placing the InterStim lead and generator. The InterStim lead is placed in the same location as the test wires. That is, the InterStim lead is placed near the S3 nerve root in the lower part of the back with the patient lying on their abdomen. For this second step, the patient is under IV sedation. With IV sedation the patient is sleepy but able to answer some simple questions at certain times during the procedure.
A 6cm (about 3 inches) incision in the right buttock is used to implant the generator, which is about the size of a tiny cell phone, and it is placed into the buttocks and connected to the InterStim lead. This generator can be programmed with an external magnet to set the intensity and frequency of the stimulation to a level that produces the desired results.
Preparation for Test Implant:
You should remain NPO (nothing per OS, or mouth) after midnight the night before surgery. That is, do not let anything pass your lips after midnight before surgery. Do not take blood thinners (aspirin, advil, motrin, ibuprofen, Coumadin, or plavix) for ten days prior to surgery. You will need a driver to drive you home after surgery.
Post-op:
You will have some pain and swelling at the S3 insertion site in the lower back and along the incision on your right buttock but there should be minimal swelling.
There is a risk of infection with Interstim implantation. This almost always occurs in diabetics and almost always occurs in the first 1-2 weeks after implantation. An infected wound will usually open and separate or drain a yellowish purulent material. Some bloody drainage in the first 3 days post-op is not unusual and is not a sign of infection. An infected unit needs to be explanted.
There are cases where the generator is in a location that needs to be moved. If the generator location becomes uncomfortable it can be relocated or repositioned with a minor surgery. The battery life of the interstim generator is about 5-7 years and so a minor procedure will be required to change the battery at that time.
You will be shown how to control the interstim device by the Medtronic company representative, who will also provide you with contact information for follow up questions. You can also check out their website at www.medtronic.com.
You should follow up in the office for a post-op wound check in 2 weeks. In the meantime, keep the wound clean and dry and avoid strenuous activity or heavy lifting. You may remove the dressing from the wound in 2 days.
