Reproducibility of the rapid pull-through technique for categorizing lower esophageal sphincter pressure

Duplicate measurements of basal lower esophageal sphincter (LES) pressure using a triple-lumen catheter and the rapid pull-through technique (RPT) were performed in 250 consecutive patients to determine their reproducibility for categorizing LES pressures as normal, hypertensive, or hypotensive. For all subjects, mean LES pressure did not differ for the two measurements (25.3 +/- 1.0 vs. 26.2 +/- 1.0 mm Hg, p greater than 0.5), but the correlation coefficient was only modest (r = 0.73). Reproducibility of categorization was 92% (230 of 250 subjects), and was best for subjects with normal (170/179, 95%) or hypotensive (24/26, 92%) values (for hypertensives: 36/45, 80%). Interstudy variability was least for the hypotensive group (1.8 +/- 0.2 mm Hg) and greatest for the hypertensive group (16.4 +/- 1.9 mm Hg). Likewise, the range of individual values from the triple-lumen catheter was least for the hypotensive subjects (4.7 +/- 0.7 mm Hg) and greatest for those with hypertensive LES pressure (32.5 +/- 2.6 mm Hg). These data show that, despite its interstudy variability, the RPT reproducibly categorizes basal LES pressure in greater than 90% of cases. The technique appears least reliable in determining hypertensive LES pressure, where diaphragmatic contraction may most significantly contribute to measurement variability.