Post-mastectomy Breast Reconstruction Using Gas vs Saline Tissue Expanders: Does the Fill Type Matter?

The most common reconstruction technique following mastectomy is a two-stage technique that involves tissue expansion followed by definitive implant-based reconstruction (IBR). Tissue expanders (TEs) have classically used saline for initial fill; however, TEs with an initial gas fill (GTE) - including the CO2-based AeroForm TE and TEs initially filled with atmospheric air - have been increasingly used in the past decade. We aim to compare the outcomes in breast reconstruction for tissue expanders initially filled with saline vs. gas. PubMed was queried for studies comparing gas and saline-filled tissue expanders (STEs) used in IBR. A meta-analysis was performed on major postoperative outcomes and the required expansion and definitive reconstruction time. Eleven studies were selected and included in the analysis. No significant differences existed between tissue expansion with GTEs versus STEs for eleven of the thirteen postoperative outcomes investigated. Out of the complications investigated, only the risk of infection/cellulitis/abscess formation was significantly lower in the GTE cohort (OR = 0.62; 95% CI = 0.47 to 0.82; P = 0.0009). The time to definitive reconstruction was also significantly lower in the GTE cohort (MD = -45.85 days; 95% CI = -57.80 to -33.90; P < 0.00001). The total time to full expansion approached significance in the GTE cohort (MD = -20.33 days; 95% CI = -41.71 to 1.04; P = 0.06). A cost analysis considering TE cost and infection risk determined that GTE use saved a predicted $2,055.34 in overall healthcare costs. Surgical outcomes for both fill types are predominantly similar; however, GTEs were associated with a significantly decreased risk of postoperative infection compared to saline filled TEs. GTEs can also reduce healthcare expenditures and require less time until definitive reconstruction after placement.