711 POST-REFLUX SWALLOW-INDUCED PERISTALTIC WAVE IS IMPAIRED IN LARYNGOPHARYNGEAL AND GASTRO-OESOPHAGEAL REFLUX DISEASE

Laryngopharyngeal reflux (LPR) and gastro-oesophageal reflux disease (GORD) result from the reflux of gastric contents. The post-reflux swallow-induced peristaltic wave (PSPW) induces chemical clearance following reflux events. PSPW index is a novel parameter that has been validated in GORD, but not in LPR. This study aimed to assess the efficacy of chemical clearance by assessing PSPW indices in patients with LPR and GORD. Methods Reviewers blindly analysed off-therapy impedance-pH tracings from 187 patients divided into LPR (n = 105) or GORD (n = 82) by predominant symptom profile. Conventional impedance-pH measures and PSPW indices were analysed for the two groups. Results Mean PSPW index in the LPR group was higher than in the GORD group (39.7% (±17.7%) vs. 20.6% (±13.4%); p < 0.001). Abnormally low PSPW index (<61%) was seen in 85 (81%) of the LPR group, and 80 (97.6%) of the GORD group (p < 0.001). Area under the ROC curve for PSPW index to diagnose LPR was 0.828 (95% CI: 0.767–0.889; p < 0.001). The LPR group had a lower AET (1.5% vs. 8.1%; p < 0.001) and fewer distal reflux episodes (46.5 (±24.5) vs. 64.4 (±39); p < 0.001). Conclusion PSPW was impaired in patients with LPR as well as oesophageal GORD, indicating an abnormality of chemical clearance following a reflux episode in both groups. PSPW index was more severely impaired in gastro-oesophageal reflux disease (GORD). The present study shows PSPW index is useful in aiding in the diagnosis of both LPR and GORD.

The Value of Reflux Monitoring: The Old and the New for the Diagnosis and Assessment of GERD

Reflux monitoring has advanced from inpatient continuous pH recordings on scrolling graph paper introduced 50 years ago to modern catheter-based 24-hour and wireless multiple-day ambulatory recordings, and the capability of detecting reflux episodes irrespective of pH using impedance technology. Testing is performed off antisecretory therapy when there is no prior documentation of reflux disease, and pH-impedance monitoring can be performed on therapy in symptomatic patients with proven reflux. Prolonged wireless pH monitoring evaluates day-to-day variation in reflux exposure. New impedance-based metrics evaluating baseline impedance and post-reflux swallow induced peristaltic wave have potential to augment the diagnostic value of reflux monitoring.

Peristaltic Transport of Power-Law Fluid in an Elastic Tapered Tube with Variable Cross-Section Induced by Dilating Peristaltic Wave

The peristaltic transport of power-law fluid in an elastic tapered tube with variable cross-section induced by dilating peristaltic wave is studied. The exact solution of the expression for axial velocity, radial velocity, stream function, local shear stress, volume of flow rate and pressure gradient are obtained under the assumption of long wavelength and low Reynolds number. The effects of all parameters that appear in the problem are analyzed through graphs. The results showed that the flux is sinusoidal in nature and it is an increasing function with the increase of whereas it is a decreasing function with the increase of . An opposite behavior for shear strain is noticed compared to pressure gradient. Finally, trapping phenomenon is presented to explain the physical behavior of various parameters. It is noted that the size of the trapping bolus increases with increasing whereas it decreases as increases. MATHEMATICA software is used to plot all figures.