Prospective comparative analysis of operative variables after transabdominal pre-peritoneal and eTEP techniques for unilateral inguinal hernia with respect to hernia sac volume based on computer tomography in male patients.

BACKGROUND The impact of hernia sac volume on post-operative pain and operative time in laparoscopic transabdominal pre-peritoneal (TAPP) and enhanced-view totally extraperitoneal (eTEP) repair of unilateral inguinal hernia remains unexplored. This study aimed to evaluate differences in post-operative pain between TAPP and eTEP techniques based on hernia sac volume quantified by computed tomography (CT), with operative time as a secondary outcome.

PATIENTS AND METHODS This prospective randomised study was conducted at a single centre in Pune, Maharashtra, India, from September 2022 to August 2023. Seventy-two male patients with unilateral inguinal hernia were randomised equally into TAPP (n = 36) and eTEP (n = 36) groups. Hernia sac volume was calculated preoperatively using an ellipsoidal formula applied to diameters derived from Computed Tomography scan and expressed as a volume ratio (volume of hernia sac to volume of abdominal cavity). Post-operative pain was assessed using the Visual Analogue Scale (VAS) at 24 hrs and 36 hrs. Operative time was recorded for all procedures. Statistical analysis employed the Mann-Whitney U-test for pain scores and independent samples t-test for operative time.

RESULTS At 24 hrs, the mean VAS score was significantly lower in the eTEP group (3.06 ± 1.09) than in the TAPP group (3.97 ± 1.18; P = 0.0011). Both groups exhibited a non-linear pain response relative to sac volume, with higher pain in smaller sacs, a decrease in mid-sized sacs and a drop in larger sacs. At 36 hrs, VAS scores converged between TAPP (2.51 ± 0.74) and eTEP (2.45 ± 0.71; P = 0.73). The mean operative time was significantly shorter for eTEP (41.61 ± 5.43 min) compared to TAPP (54.83 ± 5.93 min; P = 7.19 × 10-15).

CONCLUSIONS The eTEP technique demonstrated significantly lower post-operative pain at 24 hrs and shorter operative time compared to TAPP for unilateral inguinal hernia repair. Hernia sac volume influenced pain patterns in both groups, with smaller sacs associated with higher pain scores. These findings support the consideration of hernia sac volume as a clinical parameter for planning surgical technique.