Quantifying physiologic parameters of the gastroesophageal junction during re-operative anti-reflux surgery.

Background: Hiatal hernia re-approximation during index anti-reflux surgery (ARS) contributes approximately 80% of overall change in distensibility index (DI) and, potentially, compliance of the gastroesophageal (GEJ), while sphincter augmentation contributes approximately 20%. Whether this is seen in re-operative ARS is unclear. We quantify the physiologic parameters of the GEJ at each step of robotic re-operative ARS and compare these to index ARS.

Methods: Robotic ARS with hiatal hernia repair was performed on 195 consecutive patients with pathologic reflux utilizing EndoFLIP™, of which 26 previously had ARS. Intra-operative GEJ measurements, including cross-sectional area (CSA), pressure, DI, and high-pressure zone (HPZ) length were collected pre-repair, post-diaphragmatic re-approximation, post-mesh placement, and post-lower-esophageal sphincter (LES) augmentation.

Results: Both cohorts were similar by sex and BMI and underwent similar procedures. The re-operative cohort was older (60.6 ± 15.3 vs. 52.7 ± 16.2 years, p = 0.03), had more frequent pre-operative dysphagia (69.2% vs. 42.6%, p = 0.01) and esophageal dysmotility on barium swallow (75.0% vs. 35.0%, p < 0.001) but lower rates of hiatal hernia on endoscopy (30.8% vs. 68.7%, p < 0.001) compared to index procedures. Among the re-operative cohort, the CSA decreased by 34 (IQR - 80, - 15) mm and DI 1.1 (IQR - 2.4, - 0.6) mm/mmHg (both p < 0.001). Pressure increased by 11.2 (IQR 4.7, 14.9) mmHg and HPZ by 1.5 (1,2) cm (both p < 0.001). These changes were similar to those seen in index ARS. Diaphragmatic re-approximation contributed to a greater percentage of overall change to the GEJ than did the augmentation procedure, with 72% of the change in DI occurring during hiatal closure, similar to that seen during index ARS.

Conclusions: During re-operative ARS, dynamic intra-operative monitoring can quantify the effects of each operative step on GEJ physiologic parameters. Diaphragmatic re-approximation appears to have a greater effect on GEJ physiology than does LES-sphincter augmentation during both index and re-operative ARS.