Implantable Cook-Swartz Doppler probe versus Synovis Flow Coupler for the post-operative monitoring of free flap breast reconstruction

Abstract

Background: The Cook-Swartz Doppler has long been a trusted tool for close monitoring of blood flow after microvascular reconstruction; however, device implantation requires additional operating time. Synovis Life Technologies, Inc. received FDA approval in 2010 for the Flow Coupler, which combines an end-to-end anastomotic coupler with a removable 20 MHz Doppler, allowing both procedures to be performed simultaneously. However, its short history of widespread use necessitates further evaluation in the clinical setting. The authors studied the Synovis Flow Coupler in comparison to the more well-established Cook-Swartz Doppler for effectiveness and reliability in detection of vascular compromise.

Methods: The authors reviewed 220 free flap breast reconstructions in 150 patients over a three-year period in which either the Cook-Swartz Doppler or the Synovis Flow Coupler was implanted to monitor blood flow. Outcomes measured include false-positive or false-negative rates (FPR, FNR); rates of OR take-back and salvage; and flap survival.

Results: FPR was 1.0% for the Cook-Swartz Doppler and 1.9% for the Synovis Flow Coupler (p>0.05). FNR was 0.0% for both groups. Take-back rates were 10.1% for the Cook-Swartz, and 4.5% for Synovis (p>0.05). Flap failure rates were 1.8% and 0.9% for the Cook-Swartz and Synovis devices, respectively (p>0.05).

Conclusions: Our study reveals no statistically significant differences in outcomes for free flap breast reconstruction where either the Cook-Swartz Doppler or the Synovis Flow Coupler was used to monitor blood flow to the perforator flap.

Level of evidence: III.

Keywords: Breast reconstruction; Implantable Doppler; Microvascular anastomosis; Monitoring; Venous coupler.