Bolus retention in hiatal hernia identified by high-resolution esophageal manometry with impedance

Background: Esophageal acid retention in a hiatal hernia (HH) may play a role in gastro-esophageal reflux. The aims of this study were to determine the prevalence of bolus retention (BR) in HH and to compare pressure profiles in patients with HH with BR in the hernia to those with bolus clearance (BC) through the hernia using high-resolution esophageal manometry with impedance (HREMI).

Methods: Clinical HREMI studies with HH ≥1.5 cm were analyzed for lower esophageal sphincter (LES) and crural diaphragm (CD) pressures and pressure profiles during 12 saline swallows. Impedance was analyzed for swallow retention in the HH.

Key results: Bolus retention in a HH was present in 35 of 53 (66%) patients with a HH. Patients with BR had overall lower pressure profiles including a lower basal LES pressure (14.8 ± 10.6 vs 28.9 ± 16.8 mmHg; p = 0.0001), LES-CD gradient (6.8 ± 17.9 vs 20.6 ± 12.2 mmHg; p = 0.002), residual LES pressure (2.5 ± 4.6 vs 6.1 ± 12.2 mmHg; p = 0.017), amplitude of distal esophageal contractions (83.2 ± 38.8 vs 111.2 ± 42.8 mmHg; p = 0.020), and distal contractile integral (1487 ± 1016 vs 2608 ± 1221 mmHg-cm-sec; p = 0.001) compared to the BC group. Patients with BR were more likely to have a larger sized HH compared to the BC group (3.1 ± 1.6 vs 2.1 ± 0.6 cm; p = 0.016); similar pressure changes were found when the groups were divided up by HH sizes.

Conclusions & inferences: Bolus retention was seen in 66% of patients with HH. Bolus retention in the HH was associated with larger HH size, lower LES pressure, and lower esophageal contractile pressures compared to those with BC.