Impact of PA-MSHA on Postoperative Seroma Formation and Tissue Remodeling in Rat Abdominal Wall Hernia Model.

BACKGROUND

Seroma is one of the most common postoperative complications following hernia repair. This study evaluated whether the local application of Pseudomonas aeruginosa injection (PA-MSHA) could reduce the duration of seroma and promote healing of the graft and surrounding tissues after abdominal wall incisional hernia repair.

METHODS

56 Sprague-Dawley rats were used to assess the efficacy and optimal dosage of PA-MSHA in reducing seroma formation after latissimus dorsi resection. 54 rats underwent abdominal wall hernia repair and were randomly assigned to three groups: sham, saline, or PA-MSHA. Seroma formation was monitored, and tissue samples were collected for histological and immunohistochemical analyses.

RESULTS

Among five groups, the medium-dose group (0.1 mL/kg) demonstrated the most significant reduction in seroma volume. PA-MSHA significantly shortened the duration of seroma and enhanced both early and mid-term tissue healing. Sirius Red staining indicated a significantly higher collagen type I/III ratio on days 7 and 14. Immunohistochemical analysis demonstrated elevated expression of CD68 and CD31 during the early healing phase in the PA-MSHA group. By day 28, graft shrinkage did not differ significantly among the groups.

CONCLUSIONS

Intraoperative local administration of PA-MSHA effectively reduced seroma persistence and enhanced early tissue regeneration and abdominal wall integrity without triggering excessive foreign body reactions or adverse events.