Preoperative Botulinum Toxin A (BTA) injection in abdominal wall reconstruction for subxiphoid (M1) hernias.

[INTRODUCTION] Preoperative BTA assists with fascial closure during abdominal wall reconstruction. Its efficacy in subxiphoid (M1) hernias has been questioned with high rates of component separation techniques (CST) despite BTA. To assess the role of BTA in these hernias, we compared fascial closure and recurrence rates in patients with M1 hernias requiring CST with or without preoperative BTA.

[METHODS] A prospectively maintained database at a tertiary hernia center was reviewed for M1 hernias who underwent CST, and grouped based on use of preoperative BTA. Standard univariate analysis was performed.

[RESULTS] Of 67 patients, 30 (44.8%) received preoperative BTA. BTA versus non-BTA groups had similar mean ages (56.0 ± 14.1vs.61.5 ± 11.8 years, p = 0.087), ASA score (p = 0.345), rate of diabetes (p = 0.421), and very large defect size (499.2 ± 185.5vs.416.1 ± 238.6 cm2,p = 0.144). In the BTA group, BMI was lower (28.9 ± 5.1vs.32.7 ± 7.2 kg/m2,p = 0.018), with fewer current smokers (0%vs.10.8%,p = 0.006), and more contaminated (20.0%vs.5.4%) and dirty cases (33.3%vs.13.5%) (p = 0.008). External oblique release was performed in 24 (80.0%) BTA patients versus 23 (62.2%) non-BTA (p = 0.179), posterior CST in 6 (20.0%) versus 14 (37.8%) (p = 0.133). Rates of bilateral CST (90.0%vs.94.6% p = 0.394), fascial closure (90.0%vs.94.6%,p = 0.650), overall wound complications (33.3%vs.43.2%,p = 0.458), and recurrence (6.7%vs.2.7%,p = 0.583) were similar with average follow up of 12.7 ± 18.8 versus 24.1 ± 28.2 months (p = 0.062).

[CONCLUSION] Repair of very large M1 hernias requires high rates of CST despite preoperative BTA injection. When CST is needed, BTA as a preoperative adjunct does not appear to offer benefit in terms of fascial closure rates, frequency of bilateral CST, or risk of recurrence.