Читать книгу The Esophagus - Группа авторов - Страница 225

While the Chicago Classification is primarily intended to identify primary motor disorders as the etiology of nonobstructive dysphagia or noncardiac chest pain, evaluation for esophageal motility disorders is also important in the evaluation of suspected GERD, especially when antireflux surgery is under consideration or when reflux symptoms do not respond to treatment as expected. Both EGJ barrier function and peristaltic function have important implications with regard to GERD pathophysiology. A recent international consensus group proposed a classification scheme for esophageal motor abnormalities associated with GERD: the Lyon Consensus [56, 57]. The scheme first recommends evaluation of the EGJ to assess for (i) hiatal hernia (type II or type III EGJ morphology (Figure 8.1); and (ii) hypotensive EGJ, defined by low end‐expiratory EGJ pressure (<5 mmHg) or a low EGJ‐CI (with a value of <39 mmHg•cm proposed, but calling for further evaluation of normative thresholds). Next is evaluation of peristaltic function, akin to the Chicago Classification, and classified as: (i) intact with DCI > 450 mmHg•s•cm and no break > 5 cm in the 20 mmHg isobaric contour; (ii) fragmented with ≥ 50% of supine swallows fragmented, i.e. DCI > 450 mmHg•s•cm with peristaltic breaks > 5 cm in the 20 mmHg isobaric contour; (iii) ineffective esophageal motility with ≥ 50% weak swallows (DCI 100–450 mmHg•s•cm) or failed (DCI < 100) mmHg•s•cm; or (iv) absent contractility with 100% of test swallows with DCI < 100 mmHg•s•cm [4, 37]. The third step is to assess for contractile reserve by utilizing multiple rapid swallows or a rapid drink challenge (see the section “Application of Adjunctive or Provocative maneuvers; Table 8.3) [58].