Is permanent sacral nerve stimulator implantation indicated for a patient with significant improvement in urinary and fecal incontinence symptoms during the testing phase?

Permanent Sacral Nerve Stimulator Implantation Recommendation

This patient meets all criteria for permanent sacral nerve stimulator implantation and should proceed with the procedure. 1

Rationale for Proceeding with Permanent Implantation

The patient has demonstrated >50% improvement in both urinary urgency, urinary incontinence, and fecal incontinence during the peripheral nerve evaluation (PNE) test phase, which is the established threshold for proceeding to permanent implantation. 1, 2

Key Criteria Met

For Fecal Incontinence:

• Age ≥16 years (patient is 56 years old) 1
• Absence of complete spinal cord impairment 1
• Patient capable of operating the stimulating device 1
• Symptoms refractory to conservative care 1
• Most critically: ≥50% reduction in fecal incontinence episodes during PNE trial 1, 2

For Urinary Symptoms:

• Age ≥16 years 2
• Overactive bladder syndrome with uncontrollable urge to urinate 2
• Patient capable of operating the device 2
• Symptoms refractory to conservative care 2
• ≥50% improvement during trial phase 2

Evidence Supporting This Decision

Guideline-Based Support

The American Urological Association states that "if a trial of nerve stimulation is successful, then the permanent neurostimulation device may be implanted" for patients with frequency/urgency symptoms who have failed other treatments. 2

The American Gastroenterological Association recommends a two-stage approach for SNS, with permanent implantation following successful PNE testing (defined as ≥50% symptom improvement). 1, 3

Expected Outcomes

For Fecal Incontinence:

• In the pivotal US multicenter trial, 90% of patients proceeded from temporary to permanent stimulation 1
• Long-term follow-up showed 36% achieved complete continence and 89% were deemed therapeutic successes 1
• At 48 months mean follow-up, 80% of patients remained satisfied with treatment 4

For Urinary Symptoms:

• SNS is FDA-approved for frequency/urgency indications 2
• Patients with severe refractory OAB symptoms show sustained benefit 2

Important Counseling Points Before Implantation

Device Management

• The patient must be willing and cognitively capable of using the remote control to optimize device function 2
• Battery replacement will be needed approximately every 7 years 1, 3

Potential Complications

• Pain at insertion site occurs in up to 10% of patients 1, 3
• Infection at insertion site occurs in up to 10% of patients 1, 3
• Approximately 10% of patients may require explantation (primarily for loss of efficacy) 4
• Some patients may need stimulator and/or electrode replacement during long-term follow-up 4

MRI Contraindication

• Diagnostic MRI below the head is contraindicated with the device implanted 2

Durability of Response

• Effects typically remain stable over time if maintained 2, 4
• Periodic device adjustments may be necessary 2
• Complete disappearance of symptoms is uncommon, but most patients achieve satisfactory improvement 4

Common Pitfall to Avoid

Do not delay implantation based on the ambulatory setting notation. The MCG criteria clearly state the patient meets all requirements for permanent implantation. 1 The procedure can be performed in an ambulatory surgical setting with appropriate anesthesia support, as it is typically done under local anesthesia with sedation. 5, 6