Streamlining the Fat: A Systematic Review of Active Closed Wash and Filtration in Autologous Fat Grafting After Breast Reconstruction

Although fat grafting in breast reconstruction continues to grow in popularity, the optimal technique remains elusive and outcomes are varied. This systematic review of available controlled studies utilizing active closed wash and filtration (ACWF) systems sought to examine differences in fat processing efficiency, aesthetic outcomes, and revision rates. A literature search was performed from inception to February 2022 following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) in Ovid MEDLINE (Wolters Kluwer, Alphen aan den Rijn, the Netherlands), Ovid Embase (Wolters Kluwer), and Cochrane Library (Wiley, Hoboken, NJ). Two independent reviewers screened the studies for eligibility with Covidence software. Bibliographies and citing references from selected articles were screened from Scopus (Elsevier, Amsterdam, the Netherlands). The search identified 3476 citations, with 6 studies included. Three studies demonstrated a significantly higher volume of graftable fat harvested in a significantly lower mean grafting time with ACWF than with their respective controls. With respect to adverse events, 3 studies reported significantly lower incidences of nodule or cyst formation with ACWF with respect to control. Two studies reported a significantly lower incidence of fat necrosis with ACWF vs control, with this trend upheld in 2 additional studies. Three studies reported significantly lower revision rates with ACWF with respect to control. No study reported inferiority with ACWF for any outcome of interest. These data suggest that ACWF systems yield higher fat volumes in less time than other common techniques, with decreased rates of suboptimal outcomes and revisions, thereby supporting active filtration as a safe and efficacious means of fat processing that may reduce operative times. Further large-scale, randomized trials are needed to definitively demonstrate the above trends.