[Influence of the catheter diameter on the manometric measurements of the lower esophageal sphincter (LES); with special reference to the application for children].
In order to study the influence of the catheter diameter for measurement of the LES pressure, the LES pressure of rats was measured by using 6 kinds of catheters of different diameters. The results showed that the pressure of LES was 13.8 +/- 3.7 cmH2O, 15.2 +/- 3.2 cmH2O, 18.1 +/- 4.4 cmH2O, 22.3 +/- 6.7 cmH2O, 30.3 +/- 10.0 cmH2O and 42.0 +/- 11.9 cmH2O, respectively with the catheter diameter of 3, 4, 5, 6, 8 and 10 Fr. The larger the diameter of the esophageal tube, the higher the pressure of LES, in the range of more than a 5 Fr. tube. (P less than 0.05) Even in the LES model made of the isolated esophagus of rat, the diameter-pressure curve was similar with the LES measurement of the anesthetized rats. The increased pressure of LES was caused by an increase in tension from the esophageal wall to its proper pressure. For measurement of LES pressure of rats, the catheter of 3 Fr. or 4 Fr. in the outer diameter was more suitable since there was no tension from the esophageal wall. In order to search an appropriate catheter diameter for children, the LES pressure of 11 neonates and 12 infants were either measured with various kinds of tubes. The pressure of LES of neonates was 34.4 +/- 8.4 cmH2O, 36.4 +/- 10.7 cmH2O, 39.6 +/- 10 cmH2O, 46.0 +/- 8.7 cmH2O and 61.8 +/- 22.9 cmH2O, respectively with the catheter diameter of 4, 6, 8, 10 and 12 Fr.(ABSTRACT TRUNCATED AT 250 WORDS)
D000328:Adult; D000367:Age Factors; D000818:Animals; D002404:Catheterization / Q000295:instrumentation*; D004947:Esophagus / Q000502:physiology*; D006801:Humans; D066298:In Vitro Techniques; D007223:Infant; D007231:Infant, Newborn; D008365:Manometry / Q000295:instrumentation*; D009130:Muscle, Smooth / Q000502:physiology; D051381:Rats; D013270:Stomach / Q000502:physiology