Ambulatory gastric pH monitoring: proper probe placement and normal values

Alimentary Pharmacology and Therapeutics - Tập 15 Số 8 - Trang 1155-1162 - 2001
William K. Fackler1, Michael F. Vaezi1, Joel E. Richter1
1Center for Swallowing and Oesophageal Disorders, Cleveland Clinic Foundation, Cleveland, USA.

Tóm tắt

Background: Gastric acid production may persist while patients are treated with proton pump inhibitors. Twenty‐four‐hour intragastric pH monitoring is being used to identify gastric acid in the stomach while on medical therapy.Aim: To identify the optimal region of the stomach to demonstrate the presence of gastric acid.Method: Probe locations confirmed with fluoroscopy after placement and prior to removal. In experiment 1, five volunteers underwent simultaneous, 24‐h gastro‐oesophageal pH monitoring with the pH sensors located in the gastric antrum, body, fundus and distal oesophagus. In experiment 2, five volunteers underwent simultaneous 24‐h pH monitoring with sensors located side by side in the gastric fundus assessing the reproducibility of gastric pH in this region. In experiment 3, 35 volunteers underwent 24‐h pH monitoring with pH sensors located in the distal oesophagus and gastric fundus. The mean percentage time for which pH < 4 was calculated for total, upright, and supine time periods. Results: pH profiles for the gastric fundus and body are similar—the mean percentage total time for which pH < 4 was 92.2% and 90.1%, respectively (P=N.S.). These values are significantly different from the antrum; pH < 4=54.6% (P < 0.01). pH values from the gastric fundus are highly reproducible (linear regression P= 0.004, r2=0.96). The normal values (mean ± 95th percentile) for percentage time gastric pH < 4 in the fundus were: total 95.6 ± 1.5%, upright 94.8 ± 1.8%, and supine 96.5 ± 2.3%.Conclusion: The fundus is the optimal location to evaluate the presence of gastric acid; pH values are highly reproducible in this area. Normal values for percentage time gastric pH < 4 for a healthy population are now defined.

Từ khóa


Tài liệu tham khảo

RichterJE ed.Ambulatory Esophageal Ph Monitoring Ed 2. Baltimore MD: Williams & Wilkins 1997: 77–94.

10.1097/00042737-199906001-00004

Leite LP, 1995, Control of gastric acid with high dose H2‐receptor antagonists after omeprazole failure: report of two cases., Am J Gastroenterol, 90, 1874

10.1002/lary.1991.101.s53.1

Vaezi MF, 1997, Reproducibility of proximal probe pH parameters in 24‐hour ambulatory esophageal pH monitoring, Am J Gastroenterol, 92, 825

10.1007/BF01308070

Fisher RS, 1997, Regional differences in gastric acidity and antacid distribution: is a single pH electrode enough?, Am J Gastroenterol, 92, 263

Krawiec J, 1983, Regional differences in ambient intraluminal gastric acidity after cimetidine monitored by intragastric pH‐metry, Am J Gastroenterol, 78, 272

10.3109/00365529008997637

10.1136/gut.30.5.573

10.1097/00000658-199101000-00003

10.1111/j.1572-0241.1998.00402.x

Fisher RS, 1996, A single intragastric electrode does not accurately measure intragastric acidity, Am J Gastroenterol, 91, 1167

Leite LP, 1996, Persistent acid secretion during omeprazole therapy: a study of gastric acid profiles in patients demonstrating failure of omeprazole therapy, Am J Gastroenterol, 91, 1527

Fackler WK, 1998, Does gastric pH monitoring add to the utility of esophageal pH monitoring in patients with atypical GERD failing medical therapy, Am J Gastroenterol, 93, 1615

10.1023/A:1018835806251

10.3109/00365529509096335

Barlow AP, 1994, Twenty‐four‐hour gastric luminal pH in normal subjects: Influence of probe position, food, posture, and duodenogastric reflux, Am J Gastroenterol, 89, 2006

10.1136/gut.28.9.1177

10.1016/0016-5085(85)90009-5

Mela GS, 1990, Continuous acidity monitoring in the study of gastric antisecretory drugs: pH or antilog transformation of pH, mean or median?, Am J Gastroenterol, 85, 1105

10.1080/003655299750025480

10.1016/S0016-5085(97)70075-1

10.1042/cs0800619