Esophageal pH Probe Research Articles

Noncardiac chest pain in adolescents and children with mitral valve prolapse

Chest pain in adolescents and children is usually not of cardiac origin. Of cardiac conditions commonly linked to chest pain in childhood, mitral valve prolapse (MVP) is the most prevalent, but this association has recently been questioned. In light of recent reports of gastroesophageal sources of chest pain in adults with MVP, we performed a comprehensive gastroesophageal evaluation of 17 preadolescents and adolescents with mitral valve prolapse who had chest pain as their presenting symptom. Evaluation consisted of esophageal manometry, Bernstein test, esophageal pH probe, and/or esophagogastroscopy. Fourteen of the 17 patients had at least one abnormal finding. Five patients had esophagitis, five had gastritis, one had high-amplitude esophageal contractions, one had abnormal esophageal manometry with positive Bernstein test, one had esophageal reflux and positive Bernstein test, and one had abnormal manometry with esophageal reflux. The 13 patients with esophagitis, gastritis, reflux, or positive Bernstein test were treated with antacid, with resolution of chest pain in 12 patients. Two of these patients underwent follow-up endoscopy with documentation of improvement. The patient with high-amplitude esophageal contractions was treated with dicyclomine, which resulted in resolution of chest pain. The observation that the chest pain was not related to mitral valve prolapse is important in clinical practice and raises further questions as to whether mitral valve prolapse causes chest pain.

Long-term follow-up of brain-damaged children requiring feeding gastrostomy: Should an antireflux procedure always be performed?

Due to the frequent presence of latent gastroesophageal reflux (GER) in mentally impaired children, it is now standard to perform upper gastrointestinal contrast (UGI) and pH probe studies in all children referred for feeding gastrostomy, even if they are without clinical evidence for GER. For patients with documented GER, an antireflux operation performed in conjunction with gastrostomy is usually considered mandatory. Some authors have suggested that a "protective" antireflux operation be performed at the time of gastrostomy placement in all brain-damaged children, citing a high incidence of postoperative GER in this group of patients following gastrostomy, even with a negative preoperative evaluation for GER. To evaluate this theory, we prospectively studied, over the past 6 years, all mentally retarded children referred for feeding gastrostomy with UGI contrast and esophageal pH probe studies. In total, 148 children were studied; 105 had a positive evaluation for GER and underwent gastrostomy and antireflux surgery. Of the 43 children with a negative preoperative evaluation for GER, 37 are doing well following gastrostomy alone without clinical reflux at an average follow-up of 21 months. Six of the 43 (14%) developed symptomatic GER occurring at an average of 10 months following gastrostomy placement. Five of these children have been successfully treated with an antireflux operation and the sixth patient has been successfully managed nonoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

PH-Adjusted Formula and Gastroesophageal Reflux

To facilitate the detection of postcibal gastroesophageal reflux (GER), we have constructed an infant formula from modular carbohydrate, fat, and protein components with a pH of 4 and a nutrient composition identical to standard infant formula. In comparison to standard infant formula and sugar solutions, this pH-adjusted formula demonstrates a significantly greater amount of gastroesophageal reflex during the first postcibal hour. We speculate that the greater caloric density and slower gastric emptying of regular infant formula promotes greater gastroesophageal reflux than is observed with regular dextrose feedings. This effect is obscured unless the pH of the formula is adjusted. Use of this weakly acid formula in conjunction with postcibal esophageal pH probe recording facilitates the detection and, during simultaneous apnea monitoring, potential association of symptoms with postcibal gastroesophageal reflux.

PH‐Adjusted Formula and Gastroesophageal Reflux

SummaryTo facilitate the detection of postcibal gastroesophageal reflux (GER), we have constructed an infant formula from modular carbohydrate, fat, and protein components with a pH of 4 and a nutrient composition identical to standard infant formula, in comparison to standard infant formula and sugar solutions, this pH‐adjusted formula demonstrates a significantly greater amount of gastroesophageal reflex during the first postcibal hour. We speculate that the greater caloric density and slower gastric emptying of regular infant formula promotes greater gastroesophageal reflux than is observed with regular dextrose feedings. This effect is obscured unless the pH of the formula is adjusted. Use of this weakly acid formula in conjunction with postcibal esophageal pH probe recording facilitates the detection and, during simultaneous apnea monitoring, potential association of symptoms with postcibal gastroesophageal reflux.

Prone positioning in infant gastroesophageal reflux: Is elevation of the head worth the trouble?

To determine whether head-elevated prone positioning is better than flat prone positioning for infants with gastroesophageal reflux, we studied 100 babies less than 6 months of age who were being examined for reflux with an intraluminal esophageal pH probe while the babies were in each of the two positions, with the use of a crossover design protocol. During both a 2-hour postprandial period and a fasting period, pH probe measurements in each position included (1) minutes with pH less than 4, (2) number of episodes with pH less than 4, (3) mean duration of such episodes, (4) number of such episodes longer than 5 minutes, and (5) the duration of the longest episode. Significant reductions with head elevation were found for only two of these 10 values: the frequency of reflux episodes postprandially (7.5 +/- 0.7 vs 5.9 +/- 0.5 episodes per 2 hours; p less than 0.05) and the frequency of episodes longer than 5 minutes postprandially (1.4 +/- 0.1 vs 1.2 +/- 0.1 episodes per 2 hours; p less than 0.005). There was no significant reduction in the total duration of postprandial reflux nor in any measure of reflux during the fasting period. The 90 infants in whom an abnormal degree of gastroesophageal reflux was documented had no significant differences between flat prone and head-elevated prone position for any of the 10 pH probe measurements. Head-elevated prone positioning is probably not worth the extra effort required to maintain it.

Esophagitis in infants: Morphometric histological diagnosis and correlation with measures of gastroesophageal reflux

To assess the incidence of histological esophagitis in infants <2 yr old with symptoms of gastroesophageal reflux, 35 infants were studied with esophageal suction biopsy and pH probe monitoring. Intraepithelial and lamina propria inflammatory cells, basal cell layer thickness, and papillary height were quantitated. Distal esophageal sections from infant sudden death trauma victims were used to provide normal morphometric control values. The upper limit of normal for each of the four histological parameters of esophagitis was defined as the mean plus three standard deviations. The values thus derived were similar to established adult normal values. Seventy-seven percent of the patients had at least one abnormal histological parameter (intraepithelial eosinophils or neutrophils, thickened basal cell layer, or increased papillary height) and were thus considered to have esophagitis. These measures of esophagitis all correlated well with each other, providing an internal consistency to the histological interpretation. Lamina propria eosinophilia correlated highly with intraepithelial eosinophils (r = 0.98) and was found to have a sensitivity of 41% and specificity of 89% for diagnosing histological esophagitis, defined as abnormality of any of the four histological parameters. Ninety-three percent of the patients with histological esophagitis had significant reflux as determined by pH probe monitoring. However, there was generally poor correlation between the severity of the esophagitis as quantitated by morphometric parameters and severity of the reflux as measured by pH monitoring. Esophageal suction biopsies, which provide adequate specimens for morphometric interpretation, are appropriate for diagnosing reflux esophagitis in infants.

Value of the 24 hour intraoesophageal pH monitoring in children.

Twenty four hour oesophageal intraluminal pH probe studies were performed in 114 children (range age: one month-12 years) referred for symptoms or signs compatible with gastroesophageal reflux. Forty five patients had reflux disease alone, 69 had evidence of oesophagitis which was assessed endoscopically and histologically. Recordings were also performed in 63 control patients. The occurrence of reflux was analysed for the total study period and particularly while awake, asleep, fasting, and during postcibal periods. Oesophageal acid exposure time and the number of reflux episodes lasting greater than five minutes during the total study period provided the best discrimination between patients and controls; however, 20% and 30% of all reflux patients had both normal (with 2 SD of control) acid exposure time and number of long lasting reflux episodes, respectively. Patients with oesophagitis had significantly more acid reflux than those with simple uncomplicated disease during postcibal, fasting, awake periods, but not during sleep; however, increasing severity of oesophagitis was not associated with increasing acid exposure. The ability of the intraluminal oesophageal pH test to discriminate patients with various degrees of reflux disease decreased if only postprandial pH variables were taken into account. We conclude that: (1) the 24 hour intraoesophageal pH monitoring may present false negative results that limit overall sensitivity of the test; (2) the presence of oesophagitis does not seem to be associated with increased oesophageal acid exposure during sleep; (3) limiting the pH recording to postprandial periods reduces the discriminatory power of the test.

Gastroesophageal Reflux to the Proximal Esophagus in Infants With Bronchopulmonary Dysplasia

Recurrent aspiration after gastroesophageal reflux (GER) may contribute to the severity of chronic lung disease. If so, it should be possible to document acid reflux to the proximal esophagus. Using an esophageal pH probe placed at the level of the first or second thoracic vertebra, we evaluated GER in 14 infants with bronchopulmonary dysplasia (BPD) and 13 infants without BPD. The infants with BPD had significantly less GER, as measured by the percentage of time the pH was less than 4 (3.26% +/- 7.05% vs 12.88% +/- 15.27% [mean +/- SD]), number of GER episodes per hour (0.46 +/- 0.66 vs 1.35 +/- 0.83), number of GER episodes lasting longer than 5 minutes per hour (0.10 +/- 0.23 vs 0.31 +/- 0.29), and longest GER episode (6.76 +/- 10.29 vs 26.66 +/- 38.30 minutes). Gastroesophageal reflux may be unimportant in infants with BPD, or even occasional episodes of GER may aggravate existing lung disease.

Intravenous fat emulsion (intralipid•) delays gastric EMP-tying but does not affect lower esophageal sphincter pressure (LESP) in healthy volunteers

INTRAVENOUS FAT EMULSION (INTRALIPIDO) DELAYS GASTRIC EMPTYING BUT DOES NOT AFFECT LOWER ESOPHAGEAL SPHINCTER PRESSURE (LESP) IN HEALTHY VOLUNTEERS. P. Casaubon, K.A. Dahlstram, J. Vargas, R. Hawkins, M. Mogard, M.E. Ament. Department of Pediatrics. Medicine, and Nuclear Medicine, University of California, Los Angeles. Patients receiving overnight total parenteral nutrition frequently corrplain of nausea and upper abdominal discomfort after infusion of intravenous fat emulsion. The effects of infused lipid emulsion on upper gastrointestinal motility and gastrointestinal hormones (GIH) are unclear. This was evaluated in 10 healthy male volunteers (aged 28+1.5 SEM years). Group 1: 5 volunteers were studied over a 50 hour period in the Clinical Research Center. Esophageal manometry (EM) was done on admission (day 1) followed by intra-esophageal pH monitoring for 48 hours. They were fed a standardized diet (30% fat, 55% CHO, 15% proteins and 2000t 100 calories). On day 2, standard radionucleide gastTic emptying study was performed. Blood samples were taken just before and one hour after the gastric emptying for RIA of GIH (antibodies-Gastrin 1611, CCK 5135, neurotensin L170). On the second night. Intralipido 20% (500~~) was infused overnight for 10 hours. The iollowing morning, a second gastric emptying study was done in the last hour of the lipid infusion, and GIH were reassayed. The esophageal pH probe was then discontinued and Et4 repeated. Group 11: 5 other volunteers followed the same protocol, omitting EM and 48 hours pH because Group 1 subjects showed no significant change in LESP and reflux episodes before and after lipid infusion. Al1 volunteers after eating showed a significant rise in post prandial values of gastrin and CCK, but there was no significant change after lipid infuSion. Neurotensin values remained below 6 pM in al1 the samples. Gastric emptying showed a marked delay after lipid infusion in 8/10 volunteers (without lipids: 3724 SEM%; with lipids: 5424% of activity remaining in the stomach at 90 minutes, p=O.O04). Intravenous lipid emulsions delay gastric emptying. The gastric inhibitory mechanism does not appear to be mediated by the hormonal action of CCK or neurotensin.

Gastroesophageal reflux secondary to gastrostomy tube placement.

We evaluated five children with severe psychomotor retardation who developed frequent vomiting and poor weight gain after surgical placement of a feeding gastrostomy tube. Prolonged pH probe testing before surgery did not reveal notable gastroesophageal reflux (GER). Treatment with 12-hour gastrostomy tube feeding resulted in a marked reduction in vomiting; after one year of continuous feeding, all patients had achieved significant weight gain (mean, 44.0%). Esophageal manometrics and 24-hour pH probe testing before and at the end of the 12-month continuous-feeding period demonstrated low pressures of the lower esophageal sphincter and significant GER in the five children studied. These results indicate that children may develop symptomatic GER after gastrostomy tube placement. In such patients continuous gastrostomy tube feeding may result in a cessation of vomiting and achievement of significant weight gain. Definitive antireflux surgery can then be performed with the patient in an improved nutritional state.

Barrett's esophagus in childhood

This study describes the clinical, radiologic, esophageal function test, endoscopic, and histologic findings of Barrett's esophagus in 11 children aged 6–14 yr. All had long-standing symptoms of gastroesophageal reflux, which had begun in the first year of life in 10 of the 11. Eight of the 11 patients had mid or upper esophageal strictures and 10 of the 11 required fundoplication. Most patients had low lower esophageal sphincter pressures and abnormal pH probe studies. Only 6 of the 11 children had the characteristic pink-red appearance of the mucosa at endoscopy. Fifty endoscopic biopsy specimens taken at multiple levels in the esophagus contained columnar-lined epithelium above the gastroesophageal junction. Five of the patients had specialized (intestinal-type) epithelium as part of the histologic spectrum. The clinical expression of Barrett's esophagus in children is similar to that in adults except that strictures appear to be more common in children, and the endoscopic appearance of the mucosa is not always typical in color. As in adults, gastroesophageal reflux appears to be the etiology. In children beyond infancy, Barrett's esophagus is the most common indication for antireflux surgery at our institution. Biopsy specimens should be taken from multiple levels in the esophagus to avoid overdiagnosis and to establish the diagnosis with certainty.

Chronic bronchopulmonary disease and gastroesophageal reflux in children.

Fifty-four children who had chronic bronchopulmonary disease (CBPD) were investigated for the incidence of gastroesophageal reflux (GER). An activity score for CBPD and a numerical reflux score using criteria from a pH probe study were established. Results of barium esophagography, endoscopy, and prolonged esophageal pH probe monitoring were abnormal in 67, 78, and 53% of the patients, respectively. A significant relationship was found between the CBPD activity score and the reflux score; this strongly suggests that, in the patients studied, GER was responsible for the bronchopulmonary symptoms. Antireflux therapy resulted in an improvement of the CBPD activity score in all patients who had abnormal reflux scores. The mean CBPD activity score was 4.4 and 1.3 before and after antireflux therapy, respectively (P less than 0.01). Most patients who had normal reflux scores did not improve on antireflux therapy.

1525 GASTROESOPHAGEAL REFLUX (GER) TO THE PROXIMAL ESOPHAGUS IN NEONATES WITH BRONCHOPULMONARY DYSPLASIA

Recurrent aspiration following GER may contribute to the severity of chronic lung disease. If so, it should be possible to document acid reflux to the proximal esophagus. Using an esophageal pH probe placed at the level of the 1st or 2nd thoracic vertebra, we evaluated GER in 11 infants with BPD and 9 infants with no BPD. Results (meant±SD):Control infants have frequent episodes of GER to the upper esophagus but either do not aspirate or are not embarrassed by small aspirations. Infants with BPD have significantly less GER to the proximal esophagus than non BPD babies. The reason for this is not apparent. Either GER in BPD infants is unimportant or aspiration may follow occasional episodes of GER causing severe bronchospasm as well as aggravating existing lung disease.

700 EFFICACY OF GASTRIC ACID SUPPRESSION BY CIMETIDINE IN PEDIATRIC PATIENTS

The dose of cimetidine necessary to suppress gastric acid production in pediatric patients is not well established. Consequently, we studied 9 pts (mean age 7 yr, range 8m-10yr) with GI and/or pulmonary symptoms of gastroesophageal reflux, documented by abnormal overnight esophageal pH probe. The probe was then advanced into the stomach and gastric pH recorded before and after oral doses of cimetidine: 4 pts received randomized doses (5,7.5,and 10 mg/kg) at 8-hr intervals; 5 pts received 5 and 10 mg/kg at 4-hr intervals. Age-appropriate standardized meals were given starting 1 hr following administration of the initial dose. Efficacy of gastric acid suppression was defined as gastric pH >4.RESULTS:*One pt, unresponsive to all 3 doses, was treated with 14.3 mg/kg; gastric pH measured >4 for 1.4 hrs only.CONCLUSIONS: 1) Currently used cimetidine doses of 5 and 7.5 mg/kg fail to suppress gastric acid for >1 hr in some pts. 2) Two pts were unresponsive to doses as high as 10 mg/kg. 3) Documentation of gastric acid suppression is indicated in the management of pediatric patients with peptic related disease.

EXERCISE-INDUCED GASTROESOPHAGEAL REFLUX

The effect of exercise on gastroesophageal function was assessed in 7 children who were referred for evaluation of gastroesophageal reflux (GER). Four males and three females whose ages were 12.6 ± 4.4 yr were studied. Three patients presented with exercise-induced gastrointestinal symptoms (nausea, vomiting, substernal or epigastric pain). Cardiac or pulmonary disease was present in 3 children. Maximal treadmill exercise testing using the Bruce protocol with continuous monitoring of electrocardiogram and blood pressure was performed simultaneously with an esophageal pH probe study. Other diagnostic studies included upper GI series, 24-h pH probe, esophageal motility, gastroesophageal endoscopy, and biopsies. Results demonstrated that in one patient with exercise-induced gastrointestinal symptoms, significant symptomatic GER was present throughout strenuous exercise and during recovery ⩾ 40 min); no episodes of pathologic GER occurred throughout 24-h pH probe monitoring by Euler's criteria. Exercise-induced GER also was associated with biopsy-proven esophagitis. Motility studies demonstrated esophageal sphincter competency. None of the other patients demonstrated exercise-induced GER, despite the presence of pathologic GER. Physical work capacity was normal in all children. There were no pathologic ST changes associated with exercise. This is the first report of the association between exercise-induced gastrointestinal symptoms and GER. The pathophysiology of this entity is unknown. Exercise stress testing may aid in the diagnosis of exercise-induced GER.

Gastroesophageal Reflux and Apnea

To the Editor.— The series of papers on infant apnea in the May 1983 issue of Pediatrics was interesting reading. I am curious about two aspects of the esophageal pH probe studies reported by Rosen et al.1 The authors do not specify the temporal relationship between feeding and their polygraphic studies; presumably infants were fed during both the 12-hour nocturnal studies and the eight-hour daytime studies. The material fed is quite important in pH probe studies, because frank vomiting may occur following a milk meal without a drop in esophageal pH.

Esophageal and gastric motor abnormalities in gastroesophageal reflux during infancy

Thirty-four infants with symptoms of gastroesophageal reflux were evaluated by esophageal manometry, pH probe, and gastric emptying studies. Infants with failure to thrive (group A) and recurrent pulmonary disease (group B) had more severe reflux by pH probe (41.6% and 36.3% reflux time postprandially, respectively) than the group of infants without serious sequellae of gastroesophageal reflux (group C), who had 19.0% reflux time postprandially, p < 0.01. Lower esophageal sphincter pressure did not vary significantly between infants with severe reflux and milder disease. Groups A and B had significantly decreased peristaltic amplitude in the distal body of the esophagus (28.3 ± 4.8 and 23.2 ± 5.5 mmHg, respectively) when compared to group C (50.2 ± 3.2 mm Hg, p < 0.01); in addition to a significantly increased number of nonperistaltic sequences. Gastric emptying of isotope-labeled cow's milk formula after 1 h was 20.9% and 22.8% in groups A and B, respectively; significantly delayed compared to 40.6% of the meal emptied in group C infants. Gastric retention was significantly correlated with impaired distal esophageal peristaltic amplitude (r = 0.68) and increased postprandial pH documented reflux (r = 0.60). Our results provide evidence for the diffuse nature of the upper gastrointestinal motility disorder present in severe gastroesophageal reflux of infancy.

Twenty-four-hour esophageal intraluminal pH probe testing: A comparative analysis

Twenty-four-hour esophageal intraluminal pH probe studies were performed in 49 infants and children, 22 of whom were asymptomatic. Seventeen different parameters dealing with gastroesophageal reflux were analyzed during these 24-h pH probe studies. Unlike previous investigations the symptomatic patients differed from the asymptomatic ones in the vast majority of these parameters. The symptomatic patients were significantly different from the asymptomatic ones in 13 of the 17 parameters examined. The four parameters in which the two groups were similar included the number of reflux episodes which occurred while eating, the total number of crying episodes per day, the number of reflux episodes associated with these episodes of crying, and the average duration of episodes of esophageal pH < 4 which occurred while the children were asleep. Comparisons were made between the 24-h pH probe studies and three other testing modalities; the 1-h pH probe study, esophageal manometrics, and radiographic studies of the esophagus. Twenty-one of the 27 symptomatic patients had a positive 1-h pH probe study. All asymptomatic ones had a negative 1-h pH probe examination. Lower esophageal sphincter pressures were similar in both groups, and radiographic studies were also documented to be neither sensitive nor specific. It was found that the 24-h pH probe study was useful in the evaluation of various pediatric problems associated with gastroesophageal reflux, particularly those dealing with recurrent pulmonary infections and apneic spells. Two group multivariate discriminant analysis was done in a step-down variable selection mode. This evaluation of the two groups yielded a simplified formula involving only two variables, which allows rapid and accurate analysis of this type of pH probe study.

544 EVALUATION OF FOUR DIAGNOSTIC STUDIES FOR CHILDREN WITH SUSPECTED GASTROESOPHAGEAL REFLUX (GER)

No systematic evaluation of one (1 hr. pH) and twenty-four hour (24 hr. pH) esophageal pH probe tests, barium esophagrams and esophageal manometrics (EM) has been made in pediatric age patients. We therefore studied twenty-two children without gastrointestinal disease (WNL) and twenty-seven with symptoms of GER. The former differed from the latter in thirteen of seventeen parameters analyzed on the 24 hr. pH studies (F = 10.40; p < 0.001). Twenty-one of the twenty-seven symptomatic children had positive 1 hr. pH studies (sensitivity = 77.7%) while all (WNL) ones had negative tests (specificity = 100%). Lower esophageal sphincter pressures were similar during EM in both groups (21.1 ± 1.7 mm Hg vs 21.7 ± 1.7; p > 0.5). Motility patterns were also similar. GER was seen on esophagrams in eighteen symptomatic children (sensitivity = 50%) and thirteen (WNL) ones (specificity = 18%).Conclusions:1. 24 hr. pH studies are the most sensitive and specific method for diagnosing gastroesophageal reflux in children.2. One hr. pH probe studies are very specific but lack some sensitivity.3. Esophageal manometrics are not useful for diagnosing GER during the pediatric years.4. Barium esophagrams are neither sensitive nor specific in diagnosing gastroesophageal reflux among pediatric age patients.

Gastroesophageal reflux. A review.

Gastroesophageal reflux (GER) may produce vomiting, failure to gain weight, esophagitis, heartburn, or pulmonary symptoms. Medical or surgical management depends on the severity of the symptoms. Newer diagnostic procedures such as esophageal manometry, esophageal pH probes, and nuclear scans may confirm the presence of GER. The mechanism by which GER produces different symptoms is not well understood.