[Usefulness of a disposable nasogastric tube with a pH sensor--comparison with a class pH electrode].

We evaluated a disposable nasogastric tube with a pH sensor in comparison with an external glass pH electrode with aspiration of gastric contents, continuously. The mean pH value determined by pH sensor was 3.01, and 2.99 by glass pH electrode. There was a good correlation between the two methods (r = 0.91). The agreement between the two methods was especially good when pH less than 5.0. There was a wide scattering in the data when pH greater than 5.1. When the glass pH electrode data were above 5.1, the pH sensor tended to show lower pH values than glass pH electrode.