Clinical outcomes and costs of retromuscular and intraperitoneal onlay mesh techniques in robotic incisional hernia repair.

Background: This study aims to compare clinical outcomes and financial cost of intraperitoneal onlay mesh (IPOM) versus retromuscular (RM) repairs in robotic incisional hernia repairs (rIHR).

Methods: Patients who underwent either IPOM or RM elective rIHR from 2012 to 2022 were included. Demographics, operative details, postoperative outcomes, and hospital costs were directly compared.

Results: Sixty-nine IPOM and 55 RM were included. Age and body mass index (BMI) did not differ between both groups (IPOM vs RM: 59.3 ± 11.2 years vs. 57.5 ± 14 years, p = 0.423; BMI 34.1 ± 6.3 vs. BMI 33.2 ± 6.9, p = 0.435, respectively). Comorbidities and hernia characteristics were comparable. Extensive lysis of adhesions (> 30 min) was required more often in IPOM (18 vs. 6 in RM, p = 0.034). Defect closure was achieved in 100% of RM vs. 81.2% in IPOM (p < 0.001). Median (interquartile range) postoperative pain score was higher in RM than in IPOM [5(3-7) vs. 4(3-5), respectively, p = 0.006]. Median length of stay (0 day) and same-day discharge rate did not differ between groups (p = 0.598, p = 0.669, respectively). Six (8.7%) patients in the IPOM group versus one (1.8%) patient in the RM group were readmitted to hospital within 30 days postoperatively (p = 0.099). Perioperative complications were higher in IPOM (p = 0.011; 34.8% vs. 14.5% in RM) with higher Comprehensive Complication Index® morbidity scores [0(0-12.2) vs 0(0-0) in RM, p = 0.008)], Clavien-Dindo grade-II complications (8 vs 0 in RM, p = 0.009), and surgical site events (17 vs. 5 in RM, p = 0.024). Within a follow-up period of 57(± 28) months, recurrence rates were similar between both groups. Hospital costs did not differ between groups [IPOM: $9978 (7031-12,926) vs. RM: $8961(6701-11,222), p = 0.300]. Although postoperative complication costs were higher in IPOM ($2436 vs RM: $161, p = 0.020), total costs were comparable [IPOM: $12,415(8700-16,130) vs. RM: $9123(6789-11,457), p = 0.080].

Conclusion: Despite retromuscular repairs having lower postoperative complications than intraperitoneal onlay mesh repairs, both techniques offered encouraging results in robotic incisional hernia repair at a comparable total cost.