Air versus Saline in Initial Prepectoral Tissue Expansion: A Comparison of Complications and Perioperative Patient-Reported Outcomes.

[BACKGROUND] One option to optimize prepectoral tissue expander fill volume while minimizing stress on mastectomy skin flaps is to use air as an initial fill medium, with subsequent exchange to saline during postoperative expansion. The authors compared complications and early patient-reported outcomes (PROs) based on fill type in prepectoral breast reconstruction patients.

[METHODS] Prepectoral breast reconstruction patients who underwent intraoperative tissue expansion with air or saline from 2018 to 2020 were reviewed to assess fill-type utilization. The primary endpoint was expander loss; secondary endpoints included seroma, hematoma, infection/cellulitis, full-thickness mastectomy skin flap necrosis requiring revision, expander exposure, and capsular contracture. PROs were assessed with the BREAST-Q Physical Well-Being of the Chest scale 2 weeks postoperatively. Propensity-matching was performed as a secondary analysis.

[RESULTS] Of 560 patients (928 expanders) included in the analysis, 372 had devices initially filled with air (623 expanders), and 188 with saline (305 expanders). No differences were observed for overall rates of expander loss (4.7% versus 3.0%, P = 0.290) or overall complications (22.5% versus 17.7%, P = 0.103). No difference in BREAST-Q scores was observed ( P = 0.142). Utilization of air-filled expanders decreased substantially over the last study year. After propensity matching, no differences in loss, other complications, or PROs were observed across cohorts.

[CONCLUSIONS] Tissue expanders initially filled with air seem to have no significant advantage over saline-filled expanders in maintaining mastectomy skin flap viability or PROs, including after propensity matching. These findings can help guide choice of initial tissue expander fill type.

[CLINICAL QUESTION/LEVEL OF EVIDENCE] Therapeutic, III.