Use of near infrared spectroscopy and implantable Doppler for postoperative monitoring of free tissue transfer for breast reconstruction: a systematic review and meta-analysis

Background: Failure to accurately assess the perfusion of free tissue transfer (FTT) in the early postoperative period may contribute to failure, which is a source of major patient morbidity and healthcare costs. Goal: This systematic review and meta-analysis aims to evaluate and appraise current evidence for the use of nearinfrared spectroscopy (NIRS) and/or implantable Doppler (ID) devices compared with conventional clinical assessment (CCA) for postoperative monitoring of FTT in reconstructive breast surgery. Methods: A systematic literature search was performed in accordance with the PRISMA guidelines. Studies in human subjects published within the last decade relevant to the review question were identified. Meta-analysis using random effects models of FTT failure rate and STARD scoring were then performed on the retrieved publications. Results: 19 studies met the inclusions criteria. For NIRS and ID, the mean sensitivity for the detection of FTT failure is 99.36% and 100% respectively, with average specificity of 99.36% and 97.63% respectively. From studies with sufficient reported data, meta-analysis results demonstrated that both NIRS (OR = 0.09 [0.02, 0.36], P < 0.001) and ID (OR = 0.39 [0.27, 0.95], P = 0.04) were associated with significant reduction of FTT failure rates compared to CCA. Conclusion: The use of ID and NIRS provide equivalent outcomes in detecting FTT failure and were superior to CCA. The ability to acquire continuous objective physiological data regarding tissue perfusion is a perceived advantage of these techniques. Reduced clinical staff workload and minimised hospital costs are also perceived as positive consequences of their use