This paper is only available as a PDF. To read, Please Download here.
Continuous gastric pH monitoring offers the opportunity to evaluate gastric acid secretion in humans without the need for collection of gastric aspirates. However, gastric emptying may be an important variable for the accurate measurement of gastric acid secretion using continuous gastric pH monitoring. We conducted an in vitro study (phase I) to evaluate the effect of gastric emptying on gastric pH. The in vitro study used a laboratory model in which continuous pH monitoring of a standard formula (Nutramigen, 100 mL) in a reservoir was performed while varying both the reservoir emptying rate (10% to 80%) over 1 hour and the amount of added acid (2 to 15 mEq/h: in vivo equivalent of 6 to 45 mEq/m2 BSA/h). An in vivo study (phase II) was then performed in 28 infants less than 6 months of age who had gastroesophageal reflux (GER) documented by 18- to 24-hour esophageal pH monitoring. At the end of esophageal pH monitoring, the pH electrode was advanced into the stomach for measurement of gastric pH continuously for 2 hours after a feeding of Nutramigen formula (300 mL/m2 BSA). Each patient also had a radionuclide gastric emptying study performed with the same volume of Nutramigen formula. In the in vitro model, the reservoir pH (% time pH <4) was proportional to the reservoir emptying rate only when acid was added at <15 mEq/h (<45 mEq/m2 BSA/h). Reservoir pH was independent of reservoir emptying rate when acid was added at 15 mEq/h (45 mEq/m2 BSA/h). Using the in vitro model as a reference for the in vivo studies, postprandial gastric acid secretion was estimated at>45 mEq/m2 BSA/h in 6 of 28 (21%) infants and <9 mEq/m2 BSA/h in 15 of 28 (54%) infants with GER. In conclusion, reservoir emptying affected the measurement of reservoir pH at acid secretion levels under 15 mEq/h (45 mEq/m2 BSA/h). In most infants, any measurement of gastric acid secretion by continuous gastric pH monitoring must also account for the rate of gastric emptying.
To read this article in full you will need to make a payment
Purchase one-time access:Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
One-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:Subscribe to Journal of Pediatric Surgery
Already a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
- Chronic duodenal and gastric ulcer.Surg Clin North Am. 1987; 67: 489-506
- Hypergastrinemia in children with duodenal ulcer.J Pediatr Surg. 1988; 23: 331-334
- Peptic ulcer in children.J Pediatr Surg. 1990; 25: 744-748
- Surgical or conservative treatment in hiatal hernias in children: A new decisive parameter.Surgery. 1977; 82: 573-575
- Studies of basal and peak acid output with an augmented histamine test.Gut. 1963; 4: 136-144
- Twenty-four hour intragastric acidity analysis for the future.Gut. 1986; 27: 1-9
- Day-to-day variation of 24-hour intragastric acidity.Gastroenterology. 1988; 94: 887-891
- Long-term ambulatory gastric pH monitoring: Validation of a new method and effect of H2-receptor antagonists.Gastroenterology. 1985; 88: 1842-1851
- Computerized identification of pathologic duodenogastric reflux using 24-hour gastric pH monitoring.Ann Surg. 1991; 213: 13-20
- Effects of maturation and gastric acidity on gastroesophageal reflux in infants.Am J Dis Child. 1986; 140: 1062-1064
- Effect of ranitidine on twenty-four-hour gastric acidity in infants.J Pedaitr. 1989; 114: 472-474
- Postcibal gastroesophageal reflux in children.J Pediatr Surg. 1981; 16: 487-490
- Physiologic Basis of Medical Practice. Williams & Wilkins, Baltimore, MD1985: 684-696 ed 11.
- Textbook of Medical Physiology. Saunders, Philadelphia, PA1986: 773 ed 7.
- An assessment of gastroesophageal reflux in children by extended pH monitoring of the distal esophagus.Surgery. 1978; 84: 16-23
- Gastroesophageal reflux in infants and children: Recognition and treatment.Surg Clin North Am. 1981; 61: 1101-1115
- The accuracy of abbreviated esophageal pH monitoring in children.J Pediatr Surg. 1984; 19: 848-854
- Correlation of esophageal lengths in children with height: Application to the Tuttle test without prior esophageal manometry.J Pediatr. 1979; 94: 81-84
- Gastric emptying in children with gastroesophageal reflux. I. An estimate of effective gastric emptying.J Pediatr Surg. 1987; 22: 923-926
- A study of the effect of saliva on the concentration of mucin in gastric juice and it's possible relationship to the etiology of peptic ulcer.Gut. 1967; 8: 548-552
*Presented at the 24th Annual Meeting of the Pacific Association of Pediatric Surgeons, Hong Kong, May 20–24, 1991.
© 1992 W.B. Saunders Company. All right reserved. Published by Elsevier Inc.