End expiration is more accurate than mid respiration in measuring lower esophageal sphincter pressure

Background/Aims: Two ways popularly used to measure lower esophageal sphinc ter pressure are the mid-respiratory and end-expiratory methods. The aim of th is study was to compare the suitability of these methods in the manomet ric assessment of patients with endoscopically documented esophagitis, Meth ods: Manometry was performed on 22 consecutive patients to determine whethe r medical therapy or surgery was the more appropriate treatment strategy. L ower esophageal sphincter pressure was measured during a slow station pull- through. End-expiratory lower esophageal sphincter pressure was assessed by measuring the highest trough which coincided with end expiration. Mid-resp iratory lower esophageal sphincter pressure was assessed by bracketing the highest pressure over greater than or equal to 3 respiratory cycles and mea suring the mid point. Results: Mid-respiratory lower esophageal sphincter p ressure (25.6 mm Hg) was higher (p < 0.0001) than end-expiratory lower esop hageal sphincter pressure (15.7 mm Hg). Nine (41%) end-expiratory lower eso phageal sphincter pressures were abnormally low (i.e., <10 mm Hg), whereas three (14%) mid-respiratory lower esophageal sphincter pressures were abnor mally low (i.e., <14 mm Hg; p = 0.042). Conclusion: Mid-respiratory lower e sophageal sphincter pressure measurement includes respiratory artifact and does not accurately measure lower esophageal sphincter pressure. End-expira tory sphincter pressure better identifies potential surgical candidates. Co pyright (C) 2000 S. Karger AG, Basel.