J. Holihan1, I. L. Bondre1, E. P. Askenasy2, J. A. Greenberg3, J. Keith6, R. G. Martindale5, J. S. Roth4, C. J. Wray1, L. S. Kao1, M. K. Liang1 1University Of Texas Health Science Center At Houston,Houston, TX, USA 2Baylor College Of Medicine,Houston, TX, USA 3University Of Wisconsin,Madison, WI, USA 4University Of Kentucky,Lexington, KY, USA 5Oregon Health And Science University,Portland, OR, USA 6University Of Iowa,Iowa City, IA, USA
Introduction:
The ideal location for mesh placement in open ventral hernia repair(OVHR) remains under debate. Current trends lean toward underlay (intra-peritoneal) or sublay (retro-muscular or pre-peritoneal) with onlay and inlay repairs being largely abandoned. We hypothesize that in patients undergoing OVHR, sublay versus underlay placement of mesh results in fewer recurrences and surgical site infections(SSI).
Methods:
A multi-institution retrospective study was performed of all patients who underwent OVHR from 2010-2011. All patients with mesh placed in a sublay or underlay position and with at least 1 month of clinical follow-up were included. Primary outcome was SSI as defined by the Centers for Disease Control and Prevention (CDC). Secondary outcome was hernia recurrence (assessed by clinical examination or radiographic diagnosis). Multivariable analysis was performed using backwards stepwise logistic regression adjusting for variables selected a priori (ASA, smoking, BMI, acute, primary versus incisional, prior VHR, wound class, fascial release, fascial closure, and mesh type-biologic versus synthetic). Data was also analyzed using inverse probability weighting, which corrects for selection bias and missing data.
Results:
Of 328 patients followed for a median (range) of 17.2 (1.0-50.2) months, 97(29.6%) had a sublay repair. The unadjusted rates of SSI and recurrence were lower for the sublay group compared to the underlay group (Table). Underlay repair had more superficial, mesh/deep, and organ/space SSIs. On multivariable analysis, underlay was associated with an increased risk of SSI compared to sublay (OR 2.5, 95% CI 1.1-5.2). There was no statistically significant difference in hernia recurrence between the two techniques (OR 1.0, 95% CI 0.5-2.1). Using inverse probability weighting, sublay placement of mesh had a 9.3% (4.2-14.4%) rate of SSI, and underlay placement had a 22.3% (15.2-29.4%) rate of SSI. There was no difference in recurrence between the two techniques (underlay 18.5% CI 8.9-28.3%%; sublay 15.3% CI 7.0-23.7%).
Conclusion:
In this multi-center, risk-adjusted study, sublay repair was associated with fewer SSIs than underlay repair; however, there was no difference in rates of hernia recurrence. In the absence of a randomized trial or more rigorous data, sublay mesh placement should be considered whenever possible for open ventral hernia repairs.
