Gastric emptying with gastro-oesophageal reflux

A single-center experience of using milk scintigraphy in 251 pediatric patients: A retrospective study

To report our experience with milk gastroesophageal scintigraphy and the management of gastroesophageal reflux (GER) in children. In 251 pediatric patients we recorded age, underlying disease, central nervous system (CNS) disorders, and GER management. GER management was classified based on treatment plans: grade 0, non-pharmacological treatment; grade 1, non-pharmacological but using a nasogastric tube; grade 2, pharmacological treatment; grade 3, transpyloric feeding; and grade 4, Nissen fundoplication surgery. Patients were included in classified groups with (grades 2, 3, and 4) and without (grades 0 and 1) GER treatment. We evaluated the GER height (classified based on the height of GER, grade 0; no GER, 1; GER in the lower esophagus, 2; GER in the upper esophagus), GER duration in the lower and upper esophagus, presence or absence of massive GER amounts in the lower and upper esophagus, and gastric emptying time. We compared milk scintigraphy results and patient characteristics between groups with (grades 2, 3, and 4) and without (grades 0 and 1) GER treatment. We treated 121 patients for GER. CNS disorders (presence/absence: 46/74 with vs 21/110 without treatment, P < .001). The GER height grade (1.7 ± 0.5 [range, 0-2] with vs 1.5 ± 0.7 [range, 0-2] without treatment, P = .002), massive GER amount (present/absent: 21/99 with vs 9/122 without treatment, P = .011), and duration of GER (seconds) (324.5 ± 508.3 [range, 0-1800] vs 125.0 ± 291.9 [range, 0-1750], P < .001) in the upper esophageal half differed significantly. Similarly massive GER amount (present/absent: 54/66 with vs 34/97 without treatment, P = .002) and GER duration (621.3 ± 601.0 [range, 0-1800] vs 349.8 ± 452.4 [range, 0-1800], P < .001) in the lower esophageal half differed significantly. Additionally, CNS disorders, age, and massive GER in the upper esophageal half differed significantly among grades 2 and 4 in treated patients (P < .05, P < .001, P < .05, respectively). Milk scintigraphy is useful for deciding whether GER treatment is indicated. However, the treatment plan needs to be decided based on each patient's condition.

Factors Affecting Delayed Gastric Emptying and Long-Term Outcomes of Children With Gastric Emptying

OBJECTIVES

Our study attempted to identify what factors best predict for delayed gastric emptying (DGE) and whether children respond to treatment.

METHODS

Children aged between 0 and 18 were included who had a gastric emptying scintigraphy (GES) study performed between 2009 and 2018. Baseline clinical details were recorded from clinic visit records regarding symptoms, medication, and past medical history. Results were analyzed using multivariate regression analysis and coefficient analysis. Children were followed up at 2 years to assess their symptoms and medication usage.

RESULTS

Two hundred and eighty-five children were included in the study of which 174 demonstrated DGE. All children had symptoms prior to GES, the most common symptom being that of vomiting and reflux symptoms which were present in over 90% of patients; other common symptoms like abdominal pain and nausea were seen commonly in around 30%. A genetic disorder and prior surgery were more common in children with DGE but there was no difference in presenting symptoms between normal and DGE groups. Regression analysis showed prior surgery and particularly prior abdominal surgery predicted for DGE and additionally predicted for those with highly DGE. Improvement in symptoms and reduction in medication usage was seen after 2 years.

CONCLUSIONS

This study provides one of the largest data sets looking at DGE in children. Prior surgery was found to be a key factor in predicting for highly DGE. Symptoms and medication usage did significantly reduce substantially after 2 years.

Pharmacologic treatment of GERD in adolescents: Is esophageal mucosal protection an option?

BACKGROUND

Gastroesophageal reflux disease (GERD) is still a challenging and difficult to treat condition in children. Although acid suppression represents the mainstay of treatment in adolescents, it is not devoid of adverse events, especially in the long-term.

OBJECTIVES

In this investigation we explored a new therapeutic avenue in GERD, that is esophageal mucosal protection.

DESIGN

To this end, we performed an investigator-initiated, retrospective study to evaluate the efficacy and safety of a short-term treatment with Esoxx™ medical device in 25 adolescents with GERD-related symptoms. This mucoadhesive formulation contains two natural mucopolysaccharides (sodium hyaluronate and chondroitin sulphate) and adheres to the esophageal mucosa, exerting a protective effect against refluxed gastric contents and allowing mucosal healing.

METHODS

Heartburn, epigastric burning and post-prandial regurgitation were scored with a pain VAS scale and re-evaluated after 3-week treatment with Esoxx (one stick post-prandially, three times daily).

RESULTS

All patients completed the treatment without adverse effects and with good tolerability and compliance. All the three major symptoms significantly (p<0.001) improved after treatment. No patient required additional investigation (i.e. upper Gastrointestinal endoscopy) or medication (i.e. antisecretory drugs).

CONCLUSION

The results of this pilot study suggest that esophageal mucosal protection is a promising therapeutic avenue for GERD also in children. Provided, these data be confirmed by a large, randomized clinical trial, this medical device can enter our therapeutic armamentarium against this challenging disease.

Reflux Symptoms in Gastroparesis: Correlation With Gastroparesis Symptoms, Gastric Emptying, and Esophageal Function Testing

GOAL

The goal of this study was to determine the relationship of reflux with gastroparesis (Gp), looking both at symptoms and objective testing.

BACKGROUND

Gp patients often experience gastroesophageal reflux symptoms. How the severity of reflux correlates with the severity of Gp is not known.

STUDY

Patients referred to our academic center with symptoms of Gp completed the Patient Assessment of Upper Gastrointestinal Symptoms, Hospital Anxiety and Depression Scale, and Patient Health Questionnaire (PHQ)-15. They underwent 4-hour gastric emptying scintigraphy; and, if indicated, high-resolution esophageal manometry and esophageal pH impedance (EpHI).

RESULTS

Of 755 patients from July 2013 to May 2018, 432 had Gp with Gastroparesis Cardinal Symptom Index (GCSI) total score of 3.2±0.1 (mean±SEM) and heartburn/regurgitation subscore of 2.0±0.1. A fourth (27.1%) of all Gp patients had moderate to very severe heartburn/regurgitation symptoms. Heartburn/regurgitation subscore had strong correlation with GSCI total score (r=0.56, P<0.01), and weak correlation with 4-hour gastric retention (r=0.11, P=0.02). In total, 103 Gp patients underwent EpHI monitoring; time esophageal pH<4 had no correlation with heartburn/regurgitation subscore. Less than half (41.7%) of the patients undergoing EpHI had gastroesophageal reflux disease by EpHI. Gp patients with gastroesophageal reflux disease had more severe 4-hour gastric retention, and more frequently had decreased lower esophageal sphincter resting pressure and esophageal motility disorders. Heartburn/regurgitation subscore had moderate correlation with somatic symptoms, and weak correlations with anxiety and depression.

CONCLUSIONS

The severity of reflux symptoms in Gp has strong correlation with GCSI total score, weak correlation with gastric retention, and no correlation with esophageal pH monitoring.

Gastric emptying of milk in infants and children up to 5 years of age: normative data and influencing factors

BACKGROUND

Gastric emptying scintigraphy is widely used in infants and children, but there is a lack of age-specific normative data.

OBJECTIVE

The objectives of this retrospective study were: 1) to establish a range of gastric emptying of milk or formula as a surrogate for normal gastric emptying in infants and young children ≤5 years of age, and 2) to investigate the effects of patient age, feeding volume, feeding route and gastroesophageal reflux on gastric emptying.

MATERIALS AND METHODS

The reports of 5,136 gastric emptying studies of children ≤5 years of age performed at Children's National Medical Center from January 1990 to August 2012 were reviewed. Demographic data, 1-h and 3-h gastric emptying values and gastroesophageal reflux status of all patients were stored in a database. Using stringent inclusion and exclusion criteria, the studies of patients as similar to healthy children as possible were selected for this study.

RESULTS

The study group included 2,273 children (57% male) ages 0-59 months (median: 4.6 months). The median 1-h gastric emptying was 43% (interquartile range [IQR] 34-54%). The median 3-h gastric emptying was 91% (IQR 79-98%). Sixty-one percent of patients with 1-h gastric emptying value of <50% had 3-h gastric emptying ≥80%. Gastric emptying was significantly faster in children ≤6 months as compared with all older age groups. In each age group, the median gastric emptying decreased with increasing feeding volume. Gastric emptying was significantly faster in patients fed via combined nasogastric tube and oral routes as compared with those fed exclusively orally. There was no significant difference in gastric emptying of children with and without gastroesophageal reflux.

CONCLUSION

Although there are statistically significant differences in gastric emptying based on age, volume and route of feeding, the data suggest that overall normal liquid gastric emptying in infants and children ≤5 years of age is ≥80% at 3 h. One-hour emptying measurements are not reliable for detecting delayed gastric emptying.

Update on pediatric gastroparesis: A review of the published literature and recommendations for future research

BACKGROUND

Due to scarcity of scientific literature on pediatric gastroparesis, there is a need to summarize current evidence and identify areas requiring further research. The aim of this study was to provide an evidence-based review of the available literature on the prevalence, pathogenesis, clinical presentation, diagnosis, treatment, and outcomes of pediatric gastroparesis.

METHODS

A search of the literature was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines with the following databases: PubMed, EMBASE, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, and Web of Science. Two independent reviewers screened abstracts for eligibility.

KEY RESULTS

Our search yielded 1085 original publications, 135 of which met inclusion criteria. Most articles were of retrospective study design. Only 12 randomized controlled trials were identified, all of which were in infants. The prevalence of pediatric gastroparesis is unknown. Gastroparesis may be suspected based on clinical symptoms although these are often non-specific. The 4-hour nuclear scintigraphy scan remains gold standard for diagnosis despite lack of pediatric normative comparison data. Therapeutic approaches include dietary modifications, prokinetic drugs, and postpyloric enteral tube feeds. For refractory cases, intrapyloric botulinum toxin and surgical interventions such as gastric electrical stimulation may be warranted. Most interventions still lack rigorous supportive data.

CONCLUSIONS

Diagnosis and treatment of pediatric gastroparesis are challenging due to paucity of published evidence. Larger and more rigorous clinical trials are necessary to improve outcomes.

Stomach frame-count-based attenuation correction of dynamic posterior view gastric emptying scintigraphy with continuous acquisition in children

BACKGROUND

When performing dynamic gastric emptying scintigraphy with continuous acquisition in children, a single posterior view acquisition is preferred because it allows the young patient to more easily interact with a parent or technologist even though this method tends toward overestimating gastric emptying.

OBJECTIVES

The objective of our study was to develop a new attenuation correction (AC) method to improve the accuracy of the time activity curve and the measurement of residual gastric emptying from 1-h posterior images of gastric emptying scintigraphy with continuous acquisition.

MATERIALS AND METHODS

We developed a frame-count-based AC for gastric emptying scintigraphy from the posterior view (posterior AC method). We retrospectively reviewed 122 gastric emptying studies performed in children using conjugated posterior and anterior views, and evaluated the statistical differences between posterior only (without AC) and posterior AC using the geometric mean method as a reference standard.

RESULTS

The residual values obtained using posterior AC were not significantly different (P=0.813) compared to those using the geometric mean while the values using the posterior only were significantly different (P<0.001) from the geometric mean.

CONCLUSION

The proposed method can replace the geometric mean method to estimate gastric emptying residual fraction using patient-friendly posterior view without a significant difference in 1-h gastric emptying scintigraphy with continuous acquisition.

Patterns of reflux in gastroesophageal reflux disease in pediatric population of New South Wales

This study is to determine the association of ambulatory pH monitoring (24hr pH) with symptoms of gastroesophageal reflux and its other investigations. The clinical and epidemiological profiles of subjects referred for reflux disorders are also studied. Symptoms or group of symptoms, profiles and prior investigations of 1259 consecutive pediatric subjects (with 1332 24hr pH studies performed) referred for evaluation of reflux disorders between 1988 and 2012 were retrospectively studied. Chi-square or fisher exact test was used for hypothesis testing, student t-test for the comparison of means and the Wilcoxon rank-sum test for comparing medians of continuous variables. Gastroesophageal reflux disease (GERD), defined as reflux causing major symptoms and complications, was diagnosed in 57.5% subjects of the total sample. Forty-three percent were girls and 56.7% were boys. The most common age group was between 4 months and 2 years (51.2%). Vomiting (64.4%) and irritability (74%) were the most common symptoms with the neurological conditions (23.2%) being the most frequent underlying condition. The parameters used in 24hr pH were significantly higher in those diagnosed with GERD (P < 0.0001). The prevalence of GERD was found to be significantly higher when both gastrointestinal and respiratory symptoms were present (P = 0.008) at 66.4% than when compared with gastrointestinal (56.5%) and respiratory (52.2%) symptoms in isolation. Symptoms alone were not reliable in diagnosing GERD. Only 57.5% had GERD among patients referred for reflux disorders. 24hr pH is reliable and should be considered routine in reflux disorders, as it identifies patients with pathologic reflux and avoids a needless surgery.

Assessment of gastric emptying in children: Establishment of control values utilizing a standardized vegetarian meal

BACKGROUND AND AIM

Disorders of gastric emptying constitute an important group of conditions in children. The diagnostic gold standard is scintigraphy, and recommendations for standardization have been published with adult normative data. Pediatric literature lacks standardized age specific normative values. Our aim was to establish normal values of solid phase gastric emptying utilizing scintigraphy in children (5-18 years) using the recommended imaging protocol and standardized meal.

METHODS

Gastric emptying was assessed by scintigraphy of a (99m) Tc-labeled vegetarian meal. Image acquisition was dynamic for first hour and static at 2, 3, and 4 h. Results were reported as percent intragastric retention; lag phase defined as time to 5% emptying.

RESULTS

Thirty (17 boys) healthy children, mean ages of 9.5 ± 3.1 (range 5 to 16) years, were enrolled. Median values (5th and 95th percentiles) for percent gastric retention at 30 min, 1, 2, 3 and 4 h were 90% (76 and 100%), 77% (56 and 96%), 33% (10 and 71%), 16% (3 and 44%), and 7% (0.5 and 22%). The median (5th and 95th percentiles) lag phase was 18 min (6 and 60 min). Lag phase had no correlation with gastric retention at 4 h.

CONCLUSIONS

This study provides valuable normative ranges for solid phase gastric emptying in children. Using adult normative data in children may be inappropriate.

Causal relationship between delayed gastric emptying and gastroesophageal reflux in patients with neurological impairment

PURPOSE

To investigate the causal relationship between delayed gastric emptying (DGE) and gastroesophageal reflux (GER) in patients with neurological impairment (NI).

METHODS

Subjects included 30 NI patients (age, 1-34 years; median, 6 years). Combined multichannel intraluminal impedance-pH (MII-pH) monitoring and (13)C-breath test evaluated acid/non-acid reflux episodes (RE) and gastric emptying rates, respectively. Values are shown with medians and ranges.

RESULTS

Percentage time for esophageal pH < 4.0 (reflux index: RI) and numbers for total RE and RE > 5 min were 8.3 (0-35.7), 44 (0-129), and 5 (0-22), respectively. Total percentage time and bolus RE numbers were 1.4 (0.0-6.9) and 49 (2-159), respectively. Median bolus clearance time was 16 s (9-45). T 1/2, T lag, and GEC were 103 s (75-204), 54 s (18-97), and 3.4 (2.3-4.3), respectively. Gastric emptying rates and acid/non-acid reflux parameters were not significantly correlated, except T 1/2 correlated significantly with the numbers of RE > 5 min (p = 0.04). T 1/2 inversely correlated with bolus clearance time (p = 0.01). Reflux parameters between DGE and non-DGE patients were not significantly different, except median bolus clearance time was significantly shorter in DGE patients (p = 0.01).

CONCLUSIONS

NI patients showed a wide range of gastric emptying rates without any significant causal relationship between DGE and GER.

Tube feeding increases the gastric-emptying rate determined by gastroesophageal scintigraphy

OBJECTIVE

The aim of this study was to determine whether tube feeding affects the rate of gastric emptying determined by gastroesophageal reflux scintigraphy in pediatric patients.

METHODS

Gastroesophageal reflux scintigraphy studies of 700 pediatric patients aged 1 week to 16 years were retrospectively analyzed. From these, 350 subjects received their study meal via a feeding tube, and 350 subjects received their meal as oral feeding. Gastric-emptying rate at 60 minutes was calculated, and the results compared. Stratification analysis for age, sex, and type and volume of administered meal was also performed.

RESULTS

The average rate of the gastric emptying was higher in the tube feeding compared with oral feeding group (52.9% ± 17.9% vs 44.2% ± 15.1% gastric emptying at 1 hour, P < 0.01). The prevalence of fast gastric emptying, defined as greater than 50% emptying at 60 minutes, was also higher in the tube feeding group, being registered in 59.7% (209/350 cases) versus only 31.4% (110/350 cases) in the oral feeding group, P < 0.01. The difference persisted following stratification analysis for sex, age, and type and volume of ingested meal.

CONCLUSIONS

Our findings show that tube feeding increases the rate of gastric emptying determined by gastroesophageal reflux scintigraphy in pediatric patients. The effect proved independent on such factors as sex, age, and type or volume of ingested meal.

Gastric emptying in children with gastroesophageal reflux and in healthy children

PURPOSE

The aim of this report is to examine whether children with gastroesophageal reflux (GER) have delayed gastric emptying compared to healthy children.

METHODS

All patients had GER verified by 24-hour pH monitoring. Gastric emptying of cow's milk was examined by radionuclide scintigraphy in 51 patients with GER and in 24 controls. Gastric emptying rate was expressed as exponential half time (T1/2).

RESULTS

Median age was 4.4 years [range 0.1-15.4] in patients and 6.1 years [range 2.5-10.0] in controls (p=.10). A wide range of gastric emptying rates was observed both in GER patients [range 16-121] and controls [range 29-94]. One GER patient (2%) had slower gastric emptying (T1/2=121 min) than the healthy child with the longest T1/2 (94 min). Mean T1/2 was 49 minutes (SD 20.1) and 46 minutes (SD 14.2) in GER patients and controls, respectively (p=.51).

CONCLUSIONS

Gastric emptying rate of milk was not significantly different between children with GER and healthy children. A wide range of gastric emptying rates was observed in both groups.

Gastric emptying in children: what is the best acquisition method?

OBJECTIVES

The geometric mean is the recommended method for calculating gastric emptying in adults to correct for variable attenuation during the study. In children, it has been reported that a single posterior acquisition is sufficient. Our objective was to evaluate the relation between the values of gastric emptying in children obtained by posterior view only and by the geometric mean of conjugate anterior and posterior views.

METHODS

The gastric residual of a standard meal was calculated in 81 children of different ages. The calculation of the gastric residual was performed with different methods, posterior only and geometric mean of anterior and posterior acquisitions. The variation between these 2 methods was evaluated in different age groups and different body weights.

RESULTS

There was a high correlation (r = 0.942) between the values using posterior as compared with geometric mean for all of the patients. For children younger than 8 years and weighing <30 kg, there was no significant difference between the 2 methods for either liquid or solid meals (P = 0.89 and P = 0.11 for age; P = 0.95 and P = 0.80 for weight). For children older than 8 years and weighing >30 kg, there was no significant difference between the 2 methods for liquids (P = 0.57 for age; P = 0.69 for weight), but there was a significant difference with solids (P < 0.0001 for both age and weight).

CONCLUSIONS

In children younger than 8 years and weighing <30 kg, acquisition of a single posterior image is sufficient for calculating gastric emptying at 1 hour postingestion for either liquid or solid meals. In children older than 8 years and weighing >30 kg, acquisition of both anterior and posterior images with geometric mean calculation is recommended when a solid meal is used. If a liquid meal is used in patients older than 8 years, the posterior only may be adequate.

Ontogeny of oral drug absorption processes in children

INTRODUCTION

A large proportion of prescribed drugs to children are administered orally. Age-related change in factors affecting oral absorption can have consequences for drug dosing.

AREAS COVERED

For each process affecting oral drug absorption, a systematic search has been performed using Medline to identify relevant articles (from inception till February 2012) in humans. This review presents the findings on age-related changes of the following processes affecting oral drug absorption: gastric pH, gastrointestinal motility, bile salts, pancreatic function, intestinal pH, intestinal drug-metabolizing enzymes and transporter proteins.

EXPERT OPINION

Clinicians should bear in mind the ontogeny of oral drug absorption processes when prescribing oral drugs to children. The authors' review shows large information gaps on almost all drug absorption processes. It is important that more knowledge is acquired on intestinal transit time, intestinal pH and the ontogeny of intestinal drug-metabolizing enzymes and drug transporter proteins. Furthermore, the ultimate goal in this field should be to predict more precisely the oral disposition of drugs in children across the entire pediatric age range.

US in the diagnosis of gastroesophageal reflux in children

Several techniques have been used to diagnose gastroesophageal reflux (GER) in children, but no single test is sufficiently accurate to completely investigate the problem. Gastroesophageal US has been described as a widely available, noninvasive and sensitive method. It provides morphological and functional information, but its role in the diagnosis of GER in children is still debated. In this paper we review diagnostic approaches to GER in children. We focus on current use of US in the management of children with suspected GER. Reports suggest that US allows exclusion of several non-GER causes of symptoms and that it provides morphological and functional data with high sensitivity and positive predictive value for the diagnosis of GER. Sonographic assessment of findings such as abdominal esophageal length, esophageal diameter, esophageal wall thickness and gastroesophageal angle provide important diagnostic indicators of reflux and related to the degree of GER. There is a need for standardization of the procedure and for defining diagnostic criteria.

Cow's Milk Allergy among Children with Gastroesophageal Reflux Disease

Background/Aims

Gastroesophageal reflux disease (GERD) and cow's milk allergy (CMA) are two common conditions that occur in infancy. This study was performed to investigate the frequency of CMA in a group of patients with GERD.

Methods

Eighty-one children with signs and symptoms of GERD were enrolled in this study. All subjects received omeprazole for 4 weeks after the initial evaluation. Empirical elimination of cow's milk from the diet was started for the patients who did not respond to the omeprazole treatment.

Results

Seventy-two cases presented with gastrointestinal signs and symptoms, whereas the remaining nine cases presented with respiratory complaints. After the initial treatment with omeprazole, two thirds of the cases (54 patients, 66.7%) responded well, and all of their symptoms were resolved. Cow's milk was eliminated from the diets of the remaining 27 patients. All signs and symptoms of GERD were resolved in this group after a 4 week elimination of cow's milk from the diet.

Conclusions

A diagnosis of CMA was considered in one third of the pediatric cases with signs and symptoms of GERD. This finding shows that CMA can mimic or aggravate all signs and symptoms of severe GERD during infancy.

Gastric emptying scans: unnecessary preoperative testing for fundoplications?

PURPOSE

Delayed gastric emptying (DGE) as indicated by preoperative gastric emptying scan (GES) is one rationale for performing a gastric emptying procedure (GEP) at time of fundoplication for gastroesophageal reflux disease (GERD). However, the role of GES and GEP in the surgical management of GERD remains unclear. We examined the use of preoperative GES in fundoplication patients.

METHODS

Retrospective chart review of patients undergoing fundoplication from 2000 to 2005 in a single institution including patient demographics, operative procedure, and postoperative outcomes at 1-year follow-up was analyzed using chi(2) test.

RESULTS

Of 76 fundoplication patients, 39 (51%) had preoperative GES with 11 patients (28%) having DGE and 16 GEP performed. Developmentally delayed children were more likely to have GES. There were no significant differences in postoperative complications, length of hospital stay, or use of anti-GERD medications at 1 year between patients who had preoperative GES and those who did not. In the developmentally delayed group, there were no differences in outcomes between those with preoperative GES and those who did not.

CONCLUSIONS

There were no differences in outcomes for GERD patients with or without preoperative GES or GEP postfundoplication. The use of GES in the management of GERD requires further evaluation.

Pediatric gastroesophageal reflux clinical practice guidelines: joint recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN)

OBJECTIVE

To develop a North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) international consensus on the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

METHODS

An international panel of 9 pediatric gastroenterologists and 2 epidemiologists were selected by both societies, which developed these guidelines based on the Delphi principle. Statements were based on systematic literature searches using the best-available evidence from PubMed, Cumulative Index to Nursing and Allied Health Literature, and bibliographies. The committee convened in face-to-face meetings 3 times. Consensus was achieved for all recommendations through nominal group technique, a structured, quantitative method. Articles were evaluated using the Oxford Centre for Evidence-based Medicine Levels of Evidence. Using the Oxford Grades of Recommendation, the quality of evidence of each of the recommendations made by the committee was determined and is summarized in appendices.

RESULTS

More than 600 articles were reviewed for this work. The document provides evidence-based guidelines for the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

CONCLUSIONS

This document is intended to be used in daily practice for the development of future clinical practice guidelines and as a basis for clinical trials.

Ontogeny of gastric emptying patterns in the human fetus

OBJECTIVE

Fetal swallowing and gastric emptying contribute importantly to amniotic fluid (AF) homeostasis and fetal gastrointestinal development. We speculated that fetal gastric emptying must be functional early in gestation to prevent rapid increases in AF. We sought to determine the human fetal ontogenic pattern of gastric emptying.

STUDY DESIGN

Gastric emptying of eighty normal fetuses at 12-39 weeks was studied. Real-time ultrasound of the fetal stomach was continuously recorded for 1 hour. The gastric area ratio (GAR) was defined as the gastric area divided by the abdominal transverse area. The delta GAR was defined as the change between the maximum and the minimum gastric area ratiox100 (expressed as percent). A change of the fetal gastric area more than the 10th percentile of the delta GAR at 36-39 weeks was used to define gastric emptying.

RESULTS

The 10th, 50th and 90th percentile of delta GAR at 36-39 weeks' was 5.2, 6.5 and 8.7%, respectively. Fetal gastric emptying was detected as early as 12 5/7 weeks of gestation. The proportion of fetuses demonstrating gastric emptying (>10th percentile delta GAR) increased with gestational age: 4/33 (12.1%) 12-23 weeks, 3/9 (33.3%) at 24-27 weeks, 8/11 (72.7%) at 28-31 weeks, 12/14 (85.7%) at 32-35 weeks, and 11/13 (84.6%) at 36-39 weeks.

CONCLUSIONS

Fetal gastric emptying occurs by the beginning of the second trimester, contributing to AF regulation. The increased frequency of gastric emptying in late gestation is likely secondary to increased swallowing, altered fetal behavioral state or endogenous production of gastrointestinal motility factors.

Dyspeptic symptoms in children: the result of a constipation-induced cologastric brake?

BACKGROUND & AIMS

Patients with constipation frequently complain of dyspeptic symptoms that may be explained by reflex inhibition of upper-gastrointestinal motor activity by colonic stimuli. We sought to evaluate the following: (1) the prevalence of functional constipation (FC) and gastric emptying characteristics in children with functional dyspepsia (FD), and (2) the efficacy of osmotic laxatives on constipation, dyspeptic symptoms, and gastric motility.

METHODS

We recruited 42 children (males/females, 22/20; mean age, 80.5 mo) affected by FD (Rome II criteria). All subjects underwent ultrasonographic measurement of the total gastric emptying time (TGEt) at baseline (T0) and after 3 months (T3). Children's bowel habits and the dyspeptic symptomatic score were evaluated at entry and after 1 (T1), 2 (T2), and 3(T3) months. Constipated patients were treated with osmotic laxatives for 3 months. Dyspeptic children without constipation represented the comparison group.

RESULTS

FC was present in 28 of 42 (66.6%) patients. Constipated dyspeptic children had significantly more prolonged TGEt than subjects without constipation (median value [interquartile range], 180 (50) vs 150 (28) min, respectively; P = .004). Patients on osmotic laxatives had a significant decrease in TGEt at 3 months (P < .001). The median dyspeptic symptomatic score as well as the number and consistency of evacuations per week significantly improved at T1 in comparison with T0 and even more at T2 and T3 (P < .001, for each).

CONCLUSIONS

In our study group, the majority of children with FD were affected by FC associated with delayed gastric emptying. Normalization of bowel habit may improve gastric emptying as well as dyspeptic symptoms.

Effect of cereal-thickened formula and upright positioning on regurgitation, gastric emptying, and weight gain in infants with regurgitation

OBJECTIVE

We compared the effect of cereal-thickened formula or postural therapy on regurgitation and gastroesophageal reflux, weight gain, and gastric emptying in infants.

METHODS

We performed a prospective trial in exclusively formula-fed infants 2 to 6 mo of age presenting with regurgitation or vomiting at least three times a day. Infants were randomized into two groups; group A received cereal-thickened formula versus group B who were placed in a postprandial upright position for 90 min and evaluated over an 8-wk period. A 90-min technetium 99m milk scintigraphy was performed before and at the end of the intervention period.

RESULTS

Thirty-one infants were included in group A and 32 in group B; at inclusion, there were no anthropometric differences between groups (P = 0.813-0.955). After 4 and 8 wk, the difference in regurgitation frequency per day between groups A and B had become significant (at 4 wk, 2.39 +/- 0.86 for group A versus 2.84 +/- 0.81 for group B, P = 0.039; at 8 wk, 1.61 +/- 0.76 for group A versus 2.38 +/- 0.83 for group B, P < 0.001). The volume ingested per meal was not different between groups after 4 wk, although this parameter showed a larger intake in group A after 8 wk (156.8 +/- 23.5 mL for group A versus 143.4 +/- 25.1 mL for group B, P = 0.035), resulting in a significant difference in mean caloric intake. Gastric emptying after 8 wk showed no significant difference between groups A and B. Group A infants had significantly greater weight gain than did group B infants after 4 wk (636.2 +/- 103.4 g for group A versus 577.4 +/- 102.7 g for group B, P = 0.03) and 8 wk (1261.3 +/- 131.4 g for group A versus 1121.4 +/- 137.2 g for group B, P < 0.001). After 8 wk of intervention, the increase in length was significantly greater in group A than in group B (5.2 +/- 0.6 cm for group A versus 4.7 +/- 0.6 cm for group B, P = 0.032).

CONCLUSION

Cereal-thickened formula is significantly more efficacious than postural therapy in decreasing the frequency of regurgitation in regurgitating infants. Treatment of regurgitation with cereal-thickened formula results in an increased caloric intake ( approximately 25%), related to increased gain in weight and length, in comparison with regular formula and positioning therapy.

Validity of 13C octanoic acid breath test for measurement of solid meal gastric emptying time in children

BACKGROUND/PURPOSE

It is important to establish a physiologic range of gastric emptying (GE) in children. Gastric emptying time measured with (99)Tc-labeled solid meal (GE(Tc)) is the gold standard. Large-scale studies with GE(Tc) are ideal but not feasible because of radiation exposure. The (13)C-labeled octanoic acid breath test (GE(13C)) does not involve radiation and is suitable for large studies. The aim of this study was to validate GE(13C) with GE(Tc) and to explore whether GE(13C) could be used to establish a physiologic range of GE in children.

METHOD

Twenty-five healthy children underwent simultaneous GE(Tc) and GE(13C) using a standardized solid test meal. The time taken for the stomach to empty half its content (T(1/2)(13C)) and solid lag phase (lag(13C)) for GE(13C) were computed from the fractional excretion of (13)C in expired air. T(1/2)(13C) and lag(13C) were compared with corresponding values obtained by GE(Tc).

RESULT

Correlation coefficient between T(1/2)(13C) and T(1/2)(Tc) was 0.69 (P < .01; r = 0.92 if 3 outliers were omitted). Correlation coefficient between lag(13C) and lag(Tc) was 0.39 (P < .05). There was good agreement between the methods by the Bland Altman method.

CONCLUSION

There is good agreement between GE(13C) and GE(Tc). GE(13C) can be safely used to establish the reference range of GE in healthy children.

Relationship between gastric emptying and gastroesophageal reflux in infants and children

PURPOSE

The aim of our study was to evaluate the relationship between gastric emptying and gastroesophageal reflux (GER) in infants and children.

METHODS AND MATERIALS

One hundred eight patients (pts) between 3 months and 5 years of age (77 boys, 31 girls) with clinical suspicion of GER disease were included in the study. Patients were divided into 2 groups according to the age range: group A, 0-2 years (57 pts), and group B, 2-5 (51 pts) years. Each group was divided into 2 subgroups according to the scintigraphic study as GER-positive and -negative. Cow's milk with Tc-99m sulfur colloid as radiotracer was used. Gastric emptying was expressed as the half emptying time (T1/2). The detection of activity in the esophagus at any time during scintigraphy was considered an indicator of GER episodes. Reflux episodes were graded as grade 1 if activity was detected on one or 2 frames and grade 2 if activity was detected on more than 2 frames.

RESULTS

Forty of the 108 patients (37%) had GER findings on scintigraphy. The comparison of gastric emptying time between positive GER scintigraphy and negative GER scintigraphy groups was not statistically significant in any age group. No association was found between age and rate of gastric emptying time. Although the comparison of T1/2 between grade 1 patients and the GER-negative group was not statistically significant, grade 2 patients showed significant differences and had prolonged gastric emptying times. Mild statistical correlation between the number of reflux episodes and gastric emptying half time was found.

CONCLUSIONS

As a conclusion, the relation between gastroesophageal reflux and delayed gastric emptying cannot be ignored. Our results support delayed gastric emptying to be a pathogenetic factor in gastroesophageal reflux in infants and children.

Gastroesophageal reflux in infancy and childhood

GER is a common reason for pediatric office visits and referrals to a pediatric gastroenterologist. This condition frequently is benign, and it is self-limited in most infants. Although a thorough history and complete physical examination usually are adequate to diagnose GER, a high index of suspicion must be maintained for other diagnoses associated with recurrent emesis, including metabolic disorders, as well as for other gastrointestinal conditions, such as pyloric stenosis and abnormalities of intestinal rotation. Behavioral or lifestyle modification usually can be implemented empirically to diagnose and manage a suspected case of uncomplicated GER. When this fails, medical therapy can be initiated, employing either a step-up or step-down approach with a PPI or H2RA. With the proven efficacy of PPIs and their availability to children, medical treatment has become the mainstay of therapy in severely affected patients; nevertheless, anti-reflux surgery is still widely performed in children with GER. Pediatricians and other primary care providers often manage infants and children who have gastrointestinal complaints, prior to referral to a pediatric gastroenterologist. Hence, they have the responsibility to educate children and families about GER, its natural history, complications, and therapeutic options. A careful history and physical examination, informed use of diagnostic studies, and a consistent approach to medical treatment are important principles that are required to guarantee the success of GER management in infants and children.

Gastric emptying of solids in normal children--a preliminary report

OBJECTIVE

The physiological range of gastric emptying in healthy children has not previously been documented. The aim of this study was to establish the range of normal gastric emptying in children aged between 5 and 10 years with a Tc 99m-labelled solid meal acceptable to most of the children.

METHODS

A list of 7 child-friendly foods was compiled. Thirty-one children aged 5 to 10 years completed a questionnaire, ranking their favourite food choices. A volume survey, to decide the weight of solid meal for the study, was carried out in 20 children. After ethical approval, gastric emptying was monitored in healthy children aged 5 to 10 years with a 99mTc-labelled solid meal selected by the methodology given hereinabove. Geometric mean counts were obtained from anterior and posterior gamma camera images, and data were used to produce normal emptying curves. In each case, a T1/2 gastric emptying time (time taken to empty half the stomach contents) was calculated.

RESULTS

The overall preference was a chocolate Technecrispy cake, and the volume survey suggested a 30-g weight for the study. Twenty-four subjects consumed the meal and completed the study. The mean T1/2 gastric emptying time was 107.2 minutes (2 SD; range, 54.6-159.8 minutes).

CONCLUSIONS

Chocolate Technecrispy cake was acceptable to most healthy children between 5 and 10 years of age and gave mean T1/2 gastric emptying time of 107.2 minutes. This meal can now be used for paediatric patients with transit problems.

Delayed gastric emptying in gastroesophageal reflux disease: the role of malrotation

The association between gastroesophageal reflux (GER) and intestinal malrotation (IM) has been well described. Delayed or impaired gastric emptying in IM is thought to be a contributing factor in the development of gastroesophageal reflux disease (GERD). The current study assessed the role of malrotation in delayed gastric emptying in children with GERD. We also evaluated the interactions between GERD, malrotation, gastric pH abnormalities, and gastric dysmotility. Sixty-seven patients between 1 and 5 years of age (mean 3.08+/-1.2) and with symptoms of GER, such as emesis, reactive or recurrent lung disease, and/or growth retardation, were studied in 2001-2005. Upper and lower gastrointestinal contrast studies were performed for the diagnosis of malrotation. Gastric motility was evaluated with a liquid gastric emptying protocol. GER was documented by upper gastrointestinal studies, scintigraphy, and/or 24-h pH monitoring. In our series of 44 children with GERD, there was an unexpectedly high incidence of IM: 54.5% (24/44). IM has previously been known to occur in 25% of patients with GERD. GERD was found in 24 (82.7%) of 29 patients with IM. Mean nuclear gastric emptying (MNGE) was 51.6+/-8.04 min in patients with isolated GERD and 96.6+/-20.5 min in children with IM and GERD. There was a statistically significant difference in MNGE time (p<0.05) between children with primary GERD and in those with GERD and IM. Esophageal pH monitoring showed that mean fraction time below pH 4 was 7.06+/-1.1% in patients with isolated GERD and 14.7+/-4.1% in patients with IM and GERD. GERD is common in children between 1 and 5 years old. Using gastric emptying studies and esophageal pH monitoring, we have shown that gastric dysmotility and esophageal pH abnormalities are highly prevalent, especially in children with malrotation compared with children with isolated GERD. These findings suggest that malrotation is an important factor responsible for delayed gastric emptying in GERD. Hence, we recommend that all infants and children with GERD and delayed gastric emptying undergo careful evaluation for malrotation.

Gastric emptying of solids in children with H. pylori-positive and H. pylori-negative non-ulcer dyspepsia

OBJECTIVE

There is currently no data available in children on possible relationships among Helicobacter pylori, gastric motility and gastric inflammation. This is a prospective study of gastric emptying (GE) in symptomatic children with and without H. pylori who met symptom-based criteria for non-ulcer dyspepsia (NUD).

METHODS

47 consecutive dyspeptic patients (23 males; age range, 7 to 18 years) were enrolled. All patients had extensive negative diagnostic investigations. Scintigraphic solid-phase gastric emptying was assessed.

RESULTS

21 H. pylori-positive and 26 H. pylori-negative patients were identified with non-ulcer dyspepsia. The groups were not different in clinical symptoms except that pain related to feeding was more frequent in infected children (P < 0.03). Nodular antral gastritis was found more frequently in the H. pylori positive group (P < 0.0001). The gastritis score was more severe in H. pylori infected than H. pylori negative patients in both fundic and body mucosa (P < 0.001). Within the H. pylori-positive NUD group, the mean half-time GE of a solid meal was significantly accelerated compared to the non-infected group (P < 0.05). There was no difference in the intragastric food distribution and curves of gastric emptying of both groups. A significant relationship was found between the degree of gastric body inflammation gastric emptying, but not antral inflammation. Gastric emptying rate did not differ by sex or age of the subjects in either group.

CONCLUSIONS

In dyspeptic children with H. pylori, gastric emptying of a solid was significantly accelerated compared with symptomatic H. pylori uninfected patients. This suggests that H. pylori is able to induce gastric emptying acceleration. Our findings add more information on H. pylori infection and gastroduodenal disease.

Discerning differences: gastroesophageal reflux and gastroesophageal reflux disease in infants

Gastroesophageal reflux (GER) is a frequently encountered problem in infancy; it commonly resolves spontaneously by 12 months of age. Caregivers are challenged to discriminate between physiologic GER and the much less common and more serious condition of pathologic gastroesophageal reflux disease (GERD). Pathologic GERD may require more extensive clinical evaluation and necessitate treatment. GERD may be primary or secondary; secondary GERD is associated with a number of genetic syndromes, chromosomal abnormalities, birth defects, or a host of neurologic conditions frequently seen in the newborn intensive care unit. This article reviews the unique anatomic, physiologic, developmental, and nutritional vulnerabilities of infants that make them susceptible to GER and GERD. The North American Society of Pediatric Gastroenterology and Nutrition have recently developed a comprehensive evidence-based clinical practice guideline that structures the diagnostic approach and treatment option in infants with suspected and confirmed GERD. These guidelines provide clear definitions of GER and GERD to aid the clinician in distinguishing between the 2 conditions. They emphasize the use of history and physical examination and discuss the indications for the use of other diagnostic procedures, such as upper gastrointestinal studies, nuclear medicine scintiscan, esophagogastroduodenoscopy with biopsy, and esophageal pH probe monitoring. Management of GERD begins with a nonpharmacologic approach; the emphasis is on positioning, a trial of a hypoallergenic formula, and thickening of feedings. When these measures fail to control symptoms, a trial of either histamine(2) antagonists or a proton pump inhibitor may be indicated. Finally, surgical treatment may be needed if all other management measures fail. New sleep recommendations for infants with GERD are now consistent with the American Academy of Pediatrics' standard recommendations. Prone sleep positioning is only considered in unusual cases, where the risk of death and complications from GERD outweighs the potential increased risk of sudden infant death syndrome (SIDS). The nursing care of infants with GER and GERD, as well as relevant issues for parent education and support, are reviewed and are essential elements in managing this common condition.

Impaired gastric motility in the gastroesophageal reflux rat model: an in vitro study

PURPOSE

The present study investigated the effects of acid and mixed reflux on the responsiveness of gastric smooth muscle in the gastroesophageal reflux (GER) rat model.

MATERIAL AND METHODS

Three groups of rat were studied encompassing acid reflux, mixed reflux and sham operation. Acid reflux was induced by pyloric ligation (AR group) and mixed reflux was induced by jejunal ligation 1 cm distal to Treitz ligament (MR group). Similar surgical manipulations were carried out in the sham operated rats (SO group). Carbachol-, serotonin-, KCl-induced contractile response and nicotine-, sodium nitroprusside-, papaverine-induced relaxant response in isolated gastric fundus smooth muscle strips were determined using in vitro muscle technique 24 h after surgery.

RESULTS

Isolated gastric fundus smooth muscle contractility to serotonin, carbachol or KCl was significantly reduced in the AR and MR groups with decreased Emax and pD(2) values compared with the SO group. Relaxant responses to nicotine was significantly increased in the AR and MR groups with increased Emax and pD(2) values compared with the SO group. Sodium nitroprusside and papaverine-induced-relaxant responses were similar in all of the groups and there was no change in agonist potency.

CONCLUSION

The present study indicates that decreased contractile and increased nicotine-induced relaxant response of the gastric smooth muscle in the surgically created GER model. These findings suggest that impaired gastric smooth muscle reactivity at least in part may play a role in gastric dysmotility in GER.

Functional dyspepsia, upper gastrointestinal symptoms, and transit in children

OBJECTIVE

To assess the prevalence of abnormal gastric emptying and small bowel transit in children with functional dyspepsia at a tertiary care center, and the relationship between abnormal gastric and small bowel transit and symptoms in pediatric patients with functional gastrointestinal disorders.

STUDY DESIGN

Patients were selected by a cross-sectional chart review based on the following inclusion criteria: (1) completion of scintigraphic study of the gastric emptying of solids at 2 hours (GE2), 4 hours (GE4), and small bowel transit at 6 hours (SBT) using a standardized egg meal labeled with 99mTechnetium sulfur colloid, and (2) gastrointestinal (GI) complaints without mucosal or organic disease. Logistic regression analysis was used to assess the association between the presence of upper GI symptoms, and each parameter of gastric and small bowel transit.

RESULTS

Children with upper GI symptoms (n=96) were identified. Among 57 children with functional dyspepsia, 40% had slow SBT. Fast GE at 4 hours, and slow SBT were independently associated with bloating. Children with fast SBT were less likely to report abdominal pain.

CONCLUSION

Incorporating assessments of gastric and small bowel transit may be useful in the evaluation of pediatric patients with upper GI symptoms and functional dyspepsia.

Pathophysiological mechanisms of gastroesophageal reflux disease in children

Gastroesophageal reflux (GER) is an extremely common pediatric problem, but only in the past few years have we developed a better understanding of its pathophysiology. This is related to the wider use of investigative tools such as flexible endoscopy, 24-hour pH monitoring, and more recently, micromanometric methods and noninvasive breath tests, which have been particularly useful in infants. This paper reviews our current understanding of the esophageal and gastric mechanisms contributing to the pathophysiology of GER. In this context, we also highlight areas where new therapeutic approaches may be beneficial.

Gastroesophageal reflux in the neonate

Physiologic GER may be a maturational phenomenon, because infants outgrow this over time. Many aspects of GERD in neonates and young infants remain incompletely understood, however, particularly the pathophysiology and long-term problems in high-risk neonates. Diagnostic and therapeutic availability is vital in infants with GER and airway compromise, apnea events, or chronic lung disease. Although most infants improve with conservative therapy, there is a dire lack of ideal pharmacologic agents that work on all the mechanisms of GER with the least consequences. Studies that permit diagnosis not only of the disease but also of the causal mechanism, better feeding strategies, and prevention of morbidity from GERD will be beneficial.

Motility disorders. Diagnosis and treatment for the pediatric patient

Motility disorders are common in children and may affect any area of the GI tract. The past decade has brought significant advances in the understanding of motility disorders in pediatrics. More sophisticated testing techniques have helped to differentiate normal from abnormal motility in children of different ages. Manometry now may be used to clarify the pathophysiologic defect underlying chest pain, dysphagia, rumination, gastroparesis, chronic intestinal pseudo-obstruction, and colonic neuromuscular disorders. Motility testing also may be used to identify the motor defect responsible for persistence of symptoms after surgery for GER or HD. New investigational techniques and prokinetic agents likely to be available in the future also were discussed.

Guidelines for evaluation and treatment of gastroesophageal reflux in infants and children: recommendations of the North American Society for Pediatric Gastroenterology and Nutrition

Gastroesophageal reflux (GER), defined as passage of gastric contents into the esophagus, and GER disease (GERD), defined as symptoms or complications of GER, are common pediatric problems encountered by both primary and specialty medical providers. Clinical manifestations of GERD in children include vomiting, poor weight gain, dysphagia, abdominal or substernal pain, esophagitis and respiratory disorders. The GER Guideline Committee of the North American Society for Pediatric Gastroenterology and Nutrition has formulated a clinical practice guideline for the management of pediatric GER. The GER Guideline Committee, consisting of a primary care pediatrician, two clinical epidemiologists (who also practice primary care pediatrics) and five pediatric gastroenterologists, based its recommendations on an integration of a comprehensive and systematic review of the medical literature combined with expert opinion. Consensus was achieved through Nominal Group Technique, a structured quantitative method. The Committee examined the value of diagnostic tests and treatment modalities commonly used for the management of GERD, and how those interventions can be applied to clinical situations in the infant and older child. The guideline provides recommendations for management by the primary care provider, including evaluation, initial treatment, follow-up management and indications for consultation by a specialist. The guideline also provides recommendations for management by the pediatric gastroenterologist. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology and Nutrition on the evaluation and treatment of gastroesophageal reflux in infants and children. The American Academy of Pediatrics has also endorsed these recommendations. The recommendations are summarized in a synopsis within the article. This review and recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the management of all patients with this problem.

Effect of intragastric volume and osmolality on mechanisms of gastroesophageal reflux in children with gastroesophageal reflux disease

OBJECTIVE

Both transient lower esophageal sphincter (LES) relaxations (TLESRs) and periods of low/absent LES pressure (LESP) are the main mechanisms of gastroesophageal reflux. These events are believed to be triggered by stimuli from different areas of the upper GI tract. We aimed at investigating the relationship between LESP profile and gastric emptying and distension after meals of different composition in 30 children with gastroesophageal reflux disease (median age 7.0 yr, range 12 months-12 yr).

METHODS

Recordings of LESP and intraesophageal pH for 1 h fasting and for 2 postprandial h were performed with a perfused sleeve catheter and flexible electrode, respectively; gastric emptying and distension of antral area were simultaneously recorded with real-time ultrasonography. Ten patients had a standard meal (group A), 10 had a high-volume meal (group B), and 10 had a high-volume and osmolality meal (group C).

RESULTS

Postprandial esophageal acid exposure was significantly higher in patients of groups B and C than in patients of group A (p < 0.01); it was also more prolonged in patients of group C than in subjects of group B (p < 0.05). A higher postfeeding rate of reflux episodes caused by TLESRs was detected in patients of groups B and C as compared with patients of group A (p < 0.01). This increase did not statistically differ in patients of groups B and C. Patients of group C exhibited a higher postprandial rate of reflux episodes associated with low/absent tone of the LES as well as a more prolonged gastric emptying time and a higher postfeeding gastric distension as compared with patients of groups A and B (p < 0.01). Finally, a significant correlation was only found between the postprandial rate of reflux events resulting from low/absent LESP and the degree of antral distension in patients of group C (p < 0.01).

CONCLUSION

Gastroesophageal reflux is worsened by increasing the volume and osmolality of meals through significant changes of LESP. Meals of high volume and meals with high volume and osmolality cause a comparable increase of reflux episodes as a result of TLESRs. However, meals with high volume and osmolality cause the higher degrees of esophageal acid exposure than meals with high volume resulting from a higher rate of reflux episodes associated with low/absent LESP. This finding correlates with a high postfeeding antral distension.

Clinical correlations in infants in the neonatal intensive care unit with varying severity of gastroesophageal reflux

BACKGROUND

Gastroesophageal reflux (GER) is frequently a benign condition in infancy with spontaneous resolution. In the neonatal intensive care unit (NICU), however, it can add to neonatal morbidity if not adequately diagnosed and treated. The objective of the current study was to analyze factors associated with GER in infants in the NICU and correlate them with the severity of the disease.

METHODS

All infants in the NICU (n = 150; born November 1994 through April 1999) who were evaluated by a five-channel pH study to rule out GER were included in the study. Infants were grouped as normal, with a reflux index (RI) of less than 6 (n = 66); mild, with RI of 6 to 14 (n = 42); and severe, with RI of more than 14 (n = 42). Maternal and neonatal data were obtained. Clinical GER was defined as the presence of feeding problems (significant gastric residue or emesis) and medical improvement with antireflux measures and medications.

RESULTS

There was no difference in birth weight, gestational age; incidence of patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis, or chronic lung disease; and treatment with aminophylline or caffeine among the groups. Infants with mild and severe GER (RI 6-14 and >14) had significantly more clinical GER than the normal group (P = 0.0001). Additionally, infants with RI more than 14 had significantly more respiratory distress syndrome, lower hematocrits at the time of study and longer length of stay than those with no or mild GER (P = 0.02).

CONCLUSION

Infants with severe GER had lower hematocrits despite receiving more blood transfusions and iron therapy. Infants with severe GER also had prolonged hospital stays. Early diagnosis and aggressive management of GER may decrease neonatal morbidity and result in earlier discharge from the NICU.

Vomiting and gastric motility in infants with cow's milk allergy

BACKGROUND

Regurgitation and vomiting are common manifestations of cow's milk protein allergy (CMPA) in infants and are usually ascribed to gastroesophageal reflux (GER). Gastric anaphylaxis can induce antral dysmotility in the rat, and therefore the hypothesis for the current study was that cow's milk in sensitized infants may impair antral motility, thereby promoting GER and reflex vomiting.

METHODS

Seven vomiting infants with CMPA and nine with primary GER underwent a challenge with cow's milk formula. Electrogastrography (EGG) was used to measure the spectral frequency (bradygastria = 1.5-2.4 cycles per minute [cpm], normogastria = 2.5-3.9 cpm, tachygastria = 4.0-9.0 cpm) and the postprandial-to-fasting power ratio of gastric electrical activity, whereas gastric half-emptying time (T1/2) was measured by electrical impedance tomography (EIT).

RESULTS

In CMPA and GER, respectively, during fasting, the frequency distribution (mean +/- SD) of the EGG was as follows: normogastria 47.9%+/-12.5% versus 52.2%+/-9.8%, bradygastria 24.1%+/-5.7% versus 22.8%+/-8.3%, and tachygastria 28.0% 8.5% versus 25.0% 8.3%. In contrast, after the cow's milk challenge, the difference between the two groups was statistically significant: normogastria 33.1%+/-8.8% versus 70.6%+/-8.6% (P < 0.0001). bradygastria 38.0%+/-15.5% versus 15.7%+/-5.2% (P = 0.002), and tachygastria 28.9%+/-10.6% versus 13.4%+/-4.6% (P = 0.001. The postprandial/ fasting power ratio (mean +/- SD) was 3.2+/-1.9 in CMPA and 8.1+/-2.1 in GER (P < 0.0001). Gastric T1/2 (mean +/- SD) of the cow's milk meal was 89.0+/-26.3 minutes versus 54.0+/-12.6 minutes (P = 0.003). In infants with GER all EGG parameters and gastric T1/2 were similar to that in 10 healthy control infants.

CONCLUSIONS

In sensitized infants, cow's milk induces severe gastric dysrhythmia and delayed gastric emptying, which in turn may exacerbate GER and induce reflex vomiting. Electrogastrography and EIT can be useful in the assessment of vomiting, GER, and CMPA in infants.

Reflux in children

Gastro-oesophageal reflux (GOR) is an extremely common paediatric problem that often runs a harmless and self-limited course. Physiological GOR however can lead to marked parental anxiety, many unnecessary investigations and often unwarranted and potentially harmful therapeutic interventions. Our ability to better define GOR and gastro-oesophageal reflux disease (GORD) has improved in the past 15 years with a better understanding of the pathophysiology in infants and children due to the development and wider use of flexible endoscopy, 24-hour oesophageal pH monitoring and, more recently, the use of micromanometric methods for studying oesophageal motility. This will be further enhanced in the future with the development of non-invasive breath testing to study gastrointestinal motility and the use of electrical impedance to study fluid movement. Our therapeutic interventions have also improved particularly in the areas of acid suppression, improved surgical techniques and most recently laparoscopic fundoplication. This chapter reviews these advances in the paediatric area especially with regard to pathophysiology, diagnostic testing and therapeutic intervention.

Dual pH probe monitoring versus single pH probe monitoring in infants on milk feeds: the impact on diagnosis

OBJECTIVES

Oesophageal pH monitoring is the gold standard technique for the detection of gastro-oesophageal reflux in adults and children. A standard parameter used to define "abnormal" reflux is the percentage of recording time for which the gastric pH is < 4. This study investigated the relevance of this measure in infants on regular milk feeds whose gastric contents and refluxate will be neutral for most of the recording time.

METHODS

Simultaneous oesophageal and gastric pH monitoring was carried out on all infants who were milk fed exclusively and admitted to hospital for suspected gastro-oesophageal reflux. In vitro studies were performed to establish the buffering capacities of the fruit juice, Dioralyte (a glucose electrolyte solution), breast milk, and milk formula feeds available on the paediatric wards.

RESULTS

Complete sets of data were obtained from 30 babies with a mean age of 4 months. Gastric pH was </= 4 for a mean (SEM) of 42.4 (4.9)% of the recording time. The mean (SEM) percentage time that oesophageal pH was < 4 for the total recording period was 6.89 (0.92)%. Recalculation of the percentage of time that the gastric pH was > 4 increased this value to 17.81 (2. 46)%. Using a cut off point of 10%, 11 of the 30 babies would have been diagnosed positive for reflux using the conventional method; however, recalculation by ignoring the time for which gastric pH was high doubled this to 22 positive for reflux.

CONCLUSION

Combined oesophageal and gastric pH monitoring greatly increases the number of positive results from tests in infants on regular milk feeds.

Reproducibility of the 13C-octanoic acid breath test for assessment of gastric emptying in healthy preterm infants

BACKGROUND

The 13C-octanoic acid breath test has been used to measure gastric emptying in preterm infants, but the reproducibility of the test has not been evaluated in this population.

METHODS

Fifty-six paired breath test analyses were performed on 28 healthy preterm infants 1 to 5 days apart using the same food type, volume, and energy content for each paired sample. Breath samples were taken before the feeding, at 5-minute intervals after feeding for 30 minutes, then each 15 minutes for 4 hours. Samples were analyzed using an isotope-ratio mass spectrometer, and 3C recovery was used to calculate values for gastric-emptying coefficient and gastric half-emptying time.

RESULTS

There was no significant difference between test results on different days in the paired samples studied. gastric-emptying coefficients for the first and subsequent samples were 2.6+/-0.1 (mean+/-SEM) and 2.7+/-0.1, respectively, and half-emptying times were 44.5+/-3.7 minutes and 41.4+/-3.2 minutes.

CONCLUSION

The 13C-octanoic acid breath test is a reliable, noninvasive, and reproducible measure of gastric emptying in preterm infants that should have wide application for use in this population.

Gastric emptying in formula-fed and breast-fed infants measured with the 13C-octanoic acid breath test

BACKGROUND

The 13C-octanoic acid breath test, a noninvasive method for measuring gastric emptying, was used to compare the gastric-emptying rate of formula-fed and breast-fed infants. Octanoic acid, a medium-chain fatty acid marked with the stable isotope 13C is immediately absorbed in the duodenum. Because gastric emptying is the rate-limiting step for the absorption of medium-chain fatty acids, the fraction of 13C expired in the breath indicates the rate of gastric emptying.

METHODS

Twenty-nine newborn infants (16 boys, 13 girls) were investigated, with parental consent. The infants had a mean gestational age at birth of 34.5 weeks (range, 27-41 weeks) and a birth weight of 2148 g (range, 960-4100 g). Their mean weight on the day of the test was 2496 g (range, 1998-4140 g), and their mean age was 23 days (range, 7-74 days). Each infant received a test meal after a maximum fasting period of 3 hours. Fourteen infants were fed formula milk (Nutrilon Premium, NV Nutricia, Zoetermeer, The Netherlands) with 13C-octanoic acid and 15 infants received expressed mother's milk mixed with 13C-octanoic acid. After obtaining two basal breath samples and the feeding, breath samples were collected using a nasal prong, every 5 minutes during the first half hour and every 15 minutes during the next 3.5 hours. Analysis of the expired 13C fraction in the breath samples was performed using isotope-ratio mass spectrometry, and the gastric emptying curve and gastric emptying parameters were determined.

RESULTS

The mean half-emptying time determined by the 13C-octanoic acid breath test was 65 minutes (range, 27-98 minutes) for the formula fed infants and 47 minutes (range, 16-86 minutes) for the breast-fed infants. The difference between the half-emptying times is significant (t-test, p < 0.05).

CONCLUSIONS

The results of the 13C-octanoic acid breath test indicated faster gastric emptying of human milk than formula. Our findings are in accordance with those in earlier studies, using the invasive-dilution technique; noninvasive and detailed ultrasonography, which is not easily used because it is operator dependent and the observation time is short; or cineesophago-gastroscintigraphy, which is less suitable for infants (because of the radiation involved). The 13C-octanoic acid breath test is a safe and noninvasive method for measuring gastric emptying in small infants and allows comparison of various feeding methods.

Effects of promethazine on porcine gastroduodenal function: a sonographic study

This sonographic study was aimed at examining the effect of sedation with promethazine (1.5 mg x kg(-1)), on gastroduodenal function in neonatal piglets. On 3 consecutive days, observations of gastroduodenal motility during the first 3 postprandial h were made in 13 animals (3 to 5 days old; 7 sleeping naturally and 6 sedated 2 h prior to feeding). Promethazine significantly reduced both the closures per min of the terminal part of the pyloric antrum and pyloric canal and the percentage of gastric contractions that were followed by closure of the terminal pyloric antrum and canal. Such actions of promethazine on motility of the gastroduodenal junction could lead to a delay in gastric emptying of ingesta with a consequent increased risk of reflux of gastric contents into the esophagus. Because gastroesophageal reflux has been associated with the pathogenesis of sudden infant death syndrome (SIDS), care should be taken if promethazine is to be used as a sedative in neonates.

Gastro-oesophageal reflux in infancy

Gastro-oesophageal reflux (GOR) is a common phenomenon in infants, which may occur with or without accompanying symptoms. Although most infants presenting with regurgitation have a normal physical examination, it is now recognized that infants may also present with a wide variety of symptoms. Oesophagitis is associated with increased oesophageal acid exposure. The determination of cause and effect is difficult, as there are many aspects of reflux disease where cause and effect relationships are cyclic. Reflux disease is present when there is an imbalance between a number of factors that can contribute to a decrease, as well as an increase, of GOR. Oesophageal pH monitoring with a semi-disposable monocrysant antimony pH catheter with three sensors is very good at documenting oesophageal acidification and gastric buffering and, therefore, quantifies acid reflux frequency and duration. However, the interpretation of the data is complex as they are influenced by numerous factors, such as position, activity (sleep, crying), feeding (frequency and composition) or medication. The duration of buffering of gastric acidity during pH monitoring might, in the future, appear to be a relevant factor in the interpretation of oesophageal pH data.

Sonographic observations of the gastroduodenal junction in neonatal piglets

Knowledge of the function of the gastroduodenal junction is important, as changes in its motility are associated with gastrointestinal disorders. Sonographic observations were made of the stomach and duodenum of 19 neonatal piglets, 2-6 d of age. Contractions of the stomach and duodenum were identified clearly; the overall rate of gastric contractions was about 4 min-1. The percentage of contractions in which there was a closure of the terminal pyloric antrum and pyloric canal varied, being 57.2% +/- 4.6% in the first postprandial hour and 43.1% +/- 3.0% in the third. Antegrade flow of digesta principally occurred preceding a closure of the pyloric antrum and canal. During contractions of the pyloric antrum, the torus pyloricus moved caudally to fill the lumen of the pyloric canal. Our sonographic method provided a noninvasive technique for studying the form and function of gastroduodenal motility in the neonate, suitable for investigating factors that alter gastric emptying.