To stage or not to stage?-A cost minimization analysis of sacral neuromodulation placement strategies

Sacral neuromodulation (SNM) is a standard therapy for refractory overactive bladder (OAB). Traditionally, SNM placement involves placement of an S3 lead with 1-3 weeks of testing before considering a permanent implant. Given the potential risk of bacterial contamination during testing and high success rates published by some experts, we compared the costs of traditional 2-stage against single-stage SNM placement for OAB.

We performed a cost minimization analysis using published data on 2-stage SNM success rates, SNM infection rates, and direct reimbursements from Medicare for 2017. We compared the costs associated with a 2-stage vs single-stage approach. We performed sensitivity analyses of the primary variables listed above to assess where threshold values occurred and used separate models for freestanding ambulatory surgery centers (ASC) and outpatient hospital departments (OHD).

Based on published literature, our base case assumed a 69% SNM success rate, a 5% 2-stage approach infection rate, a 1.7% single-stage approach infection rate, and removal of 50% of non-working single-stage SNMs. In both ASC ($17 613 vs $18 194) and OHD ($19 832 vs $21 181) settings, single-stage SNM placement was less costly than 2-stage placement. The minimum SNM success rates to achieve savings with a single-stage approach occur at 65.4% and 61.3% for ASC and OHD, respectively.

Using Medicare reimbursement, single-stage SNM placement is likely to be less costly than 2-stage placement for most practitioners. The savings are tied to SNM success rates and reimbursement rates, with reduced costs up to $5014 per case in centers of excellence (≥ 90% success).