BN SO19 - Evaluating Wrap Pressure Augmentation Ratio and Physiological Transit Time for Post-Fundoplication Dysphagia

Abstract Background Post-fundoplication dysphagia affects many patients that can often lead to significant weight loss and reduced quality of life, and prompt some to seek surgical reversal. Current diagnostic methods may not fully explain the dysphagia which may necessitate repeat oesophageal physiology testing. This study retrospectively evaluates two novel markers, Wrap Pressure Augmentation Ratio (WPAR) and Physiological Transit Time (PTT), to better understand and manage the post-fundoplication dysphagia. Method The study retrospectively reviewed 54 post-Nissen’s fundoplication patients from January 2020 to May 2024. WPAR was calculated as the ratio of the augmented wrap basal pressure to the median integrated relaxation pressure found during high-resolution manometry following the Chicago Classification guideline [1]. PTT was measured from controlled measurements of antegrade bolus movement [2] during multichannel impedance-pH studies [3]. Patients completed HODQ forms to assess dysphagia [4]. Optimal WPAR and PTT thresholds were determined using Youden’s J index from receiver operating characteristic curves. This study was ethically approved (REC 18/NW/0120, IRAS 333800). Results Out of 54 cases (female=28:26, mean age 50.6), 75.9% reported clinical dysphagia post-fundoplication. Significant correlations were found with WPAR (<1.49, p=0.017) and PTT (>0.83 minutes, p=0.028)(see Table 1). These findings suggest WPAR and PTT as effective markers for post-fundoplication dysphagia. The analysis revealed a moderate correlation between WPAR and PTT (r =-0.45, p<0.05), suggesting that lower WPAR values tend to be associated with longer PTT. SensitivityPositive Predictive Valueχ2p-valueWPAR <1.490.610.895.680.017PTT >0.83 minutes0.780.844.820.028 Table 1 showing predictive DR and PTT values for clinical dysphasia post fundoplication. Conclusion This pilot study identifies PAR and PTT as promising physiological markers for diagnosing post-fundoplication dysphagia. The moderate correlation between PAR and PTT suggests a potential link, indicating that lower pressure augmentation might be associated with slower oesophageal transit times. These markers could enhance management strategies for affected patients. However, the study's small sample size and lack of a control group limit generalizability. Larger, controlled studies are necessary to validate these findings and further explore the relationship between PAR and PTT. References [1] https://onlinelibrary.wiley.com/doi/10.1111/nmo.14058 [2] https://gut.bmj.com/content/70/Suppl_1/A215.1 [3] https://gut.bmj.com/content/68/10/1731 [4] https://www.gastrojournal.org/article/S0016-5085(09)62439-2/fulltext