Mechanisms underlying the antireflux effect of Nissen fundoplication in children

Pre- and Postgastrostomy Evaluation of Gastroesophageal Reflux in Children Using 24-Hour pH Monitoring

Background: The aim of this study was to evaluate 24-hour pH monitoring results before and after gastrostomy in neurological impaired (NI) children who underwent gastrostomy or Nissen fundoplication (NF) concurrently with gastrostomy. Materials and Methods: Between March and December 2018, NI patients who had previously received pre- and postgastrostomy (Group 1) or gastrostomy + NF (Group 2) underwent pH monitoring pre- and postoperatively. Results: Twenty patients [12 males (60%) and the median age of 5.6 (14 months-14.7 years) years] with NI were followed up during the study period. When pre- and postgastrostomy weight and BMI z-scores were compared, the results were significantly higher in both groups after procedure (P = .043, P = .040, respectively). The clinical results of the patients after the operation showed improvement in both groups. The pH index of Group 1 (n = 11) was 2.32 (0-3.8) before gastrostomy and 3.18 (2.1-6.9) after gastrostomy (P = .061) and in Group 2 (n = 9) it was 5.85 (4.9-15.8) and 0.61 (0.3-1.3), before and after procedure (P < .001). There was a statistically significant difference in reflux index of each group. This difference was not statistically significant between the groups (P = .072). When the total bolus exposure index was compared, it was 4.01 (2.1-5.2) before gastrostomy and 5.67 (4.6-6.3) after gastrostomy in Group 1 (P = .041). In group 2, that index was found to be 9.8 (8.3-10.2) before and 1.28 (0.5-1.4) after (P < .001). There was a statistically significant difference in index after gastrostomy in Groups 1 and 2 (P = .023). Conclusions: Gastrostomy feeding is an effective and safe option to achieve enteral feeding in NI children. NF concurrent with gastrostomy should be decided according to the individual patient. Clinical trials protocol registration ID number was PRS NCT00445112.

Laparoscopic Nissen fundoplication mainly reduces the volume of acid reflux and potentially improves mucosal integrity up to the middle esophagus in neurologically impaired children detected by esophageal combined pH-multichannel intraluminal impedance measurements

BACKGROUND

The aim of this study was to evaluate detailed changes of gastroesophageal reflux disease (GERD) in children before and after laparoscopic Nissen fundoplication (LNF) utilizing esophageal combined pH-multichannel intraluminal impedance (pH/MII) measurements.

PATIENTS AND METHODS

Thirteen patients with neurological impairment, who received laparoscopic Nissen fundoplication (LNF) owing to refractory pathological GERD, were enrolled in this study. 24h pH/MII was conducted in all patients before and one year after LNF. Each parameter of the pH/MII was evaluated and compared each other.

RESULTS

Both the mean pH index and bolus exposure index after LNF were significantly lower than those before LNF. The mean numbers of total and nonacid reflux episodes after LNF were significantly lower than those before LNF. The mean numbers of total, acid and nonacid proximal reflux episodes after LNF were significantly lower than those before LNF. The mean baseline impedance values from Z3 to Z6 after LNF were significantly higher than those before LNF.

CONCLUSIONS

The present study provides new insights into the effects of LNF in pediatric patients, which prevents mainly acid reflux episodes from rising to the proximal esophagus, and is expected to improve the mucosal integrity up to the middle esophagus.

Gastroesophageal reflux, esophageal function, gastric emptying, and the relationship to dysphagia before and after antireflux surgery in children

OBJECTIVES

To assess gastroesophageal reflux (GER), esophageal motility, and gastric emptying in children before and after laparoscopic fundoplication and to identify functional measures associated with postoperative dysphagia.

STUDY DESIGN

Combined impedance-manometry, 24-hour pH-impedance, and gastric-emptying breath tests were performed before and after laparoscopic anterior partial fundoplication. Impedance-manometry studies were analyzed with the use of conventional analysis methods and a novel automated impedance manometry (AIM) analysis.

RESULTS

Children with therapy resistent GER disease (n = 25) were assessed before fundoplication, of whom 10 (median age 6.4 years; range, 1.1-17.1 years; 7 male; 4 with neurologic impairment) underwent fundoplication. GER episodes reduced from 97 (69-172) to 66 (18-87)/24 hours (P = .012). Peristaltic contractions were unaltered. Complete lower esophageal sphincter relaxations decreased after fundoplication (92% [76%-100%] vs 65% [29%-91%], P = .038). Four (40%) patients developed postoperative dysphagia, which was transient in 2. In those patients, preoperative gastric emptying was delayed compared with patients without postoperative dysphagia, 96 minutes (71-104 minutes) versus 48 minutes (26-68 minutes), P = .032, and AIM analysis derived dysphagia risk index was greater (56 [15-105] vs 2 [2-6] P = .016). Two patients underwent a repeat fundoplication.

DISCUSSION

Fundoplication in children reduced GER without altering esophageal motility. Four patients who developed dysphagia demonstrated slower gastric emptying and greater dysplasia risk index preoperatively. AIM analysis may allow detection of subtle esophageal abnormalities potentially leading to postoperative dysphagia.

The effects and efficacy of antireflux surgery in children with gastroesophageal reflux disease: a systematic review

BACKGROUND

Antireflux surgery (ARS) for gastroesophageal reflux disease (GERD) is one of the most frequently performed major operations in children. Many studies have described the results of ARS in children, however, with a wide difference in outcome. This study aims to systematically review the efficacy of pediatric ARS and its effects on gastroesophageal function, as measured by gastroesophageal function tests. This is the first systematic review comprising only prospective, longitudinal studies, minimizing the risk of bias.

METHODS

Three electronic databases (Medline, Embase, and the Cochrane Library) were searched for prospective studies reporting on ARS in children with GERD.

RESULTS

In total, 17 eligible studies were identified, reporting on a total of 1,280 children. The median success rate after ARS was 86% (57-100%). The success rate in neurologically impaired children was worse in one study, but similar in another study compared to normally developed children. Different surgical techniques (total versus partial fundoplication, or laparoscopic versus open approach) showed similar reflux recurrence rates. However, less postoperative dysphagia was observed after partial fundoplication and laparoscopic ARS was associated with less pain medication and a shorter hospital stay. Complications of ARS varied from minimal postoperative complications to severe dysphagia and gas bloating. The reflux index (RI), obtained by 24-h pH monitoring (n = 8) decreased after ARS. Manometry, as done in three studies, showed no increase in lower esophageal sphincter pressure after ARS. Gastric emptying (n = 3) was reported either unchanged or accelerated after ARS. No studies reported on barium swallow x-ray, endoscopy, or multichannel intraluminal impedance monitoring before and after ARS.

CONCLUSION

ARS in children shows a good overall success rate (median 86%) in terms of complete relief of symptoms. Efficacy of ARS in neurologically impaired children may be similar to normally developed children. The outcome of ARS does not seem to be influenced by different surgical techniques, although postoperative dysphagia may occur less after partial fundoplication. However, these conclusions are bound by the lack of high-quality prospective studies on pediatric ARS. Similar studies on the effects of pediatric ARS on gastroesophageal function are also very limited. We recommend consistent use of standardized assessment tests to clarify the effects of ARS on gastroesophageal function and to identify possible risk factors for failure of ARS in children.

The Case of the Wretched Retcher

Fundoplication is an effective treatment for severe gastroesophageal reflux disease (GERD) because it provides a mechanical solution to what is essentially a mechanical, not a medical, problem. However, manifestations of feeding intolerance postfundoplasty are well known and include dysphagia, gastric dysfunction, retching, gagging, intestinal dysfunction, and gas bloat syndrome. These difficulties are exacerbated by feeding plans that disregard the mechanical constraints imposed by the operation, particularly limited gastric volume, decreased gastric compliance, diminished ability to burp, sensitivity to osmolarity, and formula composition. These complications are preventable and treatable by informed construction of feeding plans that limit boluses (around 15 mL/kg/bolus), promote proper motility, manage intraluminal air, and limit polypharmacy. This case presentation describes a postfundoplasty infant with severe retching and intolerance treated according to these principles.

Pathogenesis of gastro-oesophageal reflux disease and novel options for its therapy

Better understanding of the mechanisms that lead to reflux disease is an important area for future research, given the very high prevalence of this problem. During the lifetime of this journal, much has been learnt about the pathophysiology of reflux disease. Abnormally, frequent acid reflux plays a key role in pathogenesis: this reflux occurs predominantly during transient lower oesophageal sphincter relaxations. Analysis of the literature suggests that the importance of transient relaxations as the major permissive event for occurrence of acid reflux is currently substantially underestimated. 'Transient relaxation' is an inexact descriptor, as this motor programme includes inhibition of the diaphragmatic hiatus and distal oesophageal body circular muscle and contraction of the oesophageal longitudinal muscle. Laxity of the diaphragmatic hiatus and hiatus hernia are probably important factors that increase the probability for acid reflux to occur during transient relaxations and in allowing strain-induced reflux episodes. The importance of straining and low basal tone of the lower oesophageal sphincter in causing abnormal reflux has probably been overestimated, but these need more investigation. High resolution manometry is the key method for acquisition of important new insights into the normal and disordered mechanics of the antireflux function of the gastro-oesophageal junction, but as yet, the potential of this technique has been tapped relatively little. In the future, improved understanding of the mechanics of the gastro-oesophageal junction should lead to improved physical antireflux procedures. Much progress has been made in defining the control of transient relaxations and this has been translated into several promising options for a new class of drug that treats reflux disease by inhibition of transient relaxations. Clinical trials on these agents appear imminent.

Estudo comparativo entre as técnicas de nissen e Boix-Ochoa em ratos

OBJETIVO: Comparar, em ratos, a eficiência das técnicas de Nissen e Boix-Ochoa no tratamento do refluxo gastroesofagiano (RGE) induzido pela operação de Heller. MÉTODO: Foram usados 30 ratos Wistar, com idades entre 40 e 60 dias de vida e peso corporal entre 210 g e 342 g. Os animais foram distribuídos em três Grupos (A, B, C) de 10 ratos. Em todos os animais realizou-se a operação de Heller. No Grupo B ela foi seguida de uma operação de Nissen e, no Grupo C, de uma operação de Boix-Ochoa. A pressão intra-gástrica necessária para produzir RGE foi medida em todos os animais: antes de qualquer procedimento; imediatamente após as operações de Heller, Nissen e Boix-Ochoa; e seis semanas depois, quando os animais foram mortos. RESULTADOS: Verificou-se que tanto a recuperação da perda de peso, que caracteriza o quadro de RGE, como a reconstituição mais fisiológica dos gradientes pressóricos gastroesofagianos são obtidos de forma mais eficiente pela técnica de Boix- Ochoa. CONCLUSÃO: As operações de Nissen e Boix- Ochoa são eficientes no tratamento do RGE induzido pela técnica de Heller, em ratos. A segunda, no entanto, restaurou, de forma mais adequada, os valores fisiológicos dos parâmetros estudados neste trabalho: o peso corporal e os gradientes pressóricos gastroesofagianos.

Lack of distal esophageal contractions is a key determinant of gastroesophageal reflux disease after repair of esophageal atresia

BACKGROUND/PURPOSE

The objective of this study is to investigate the characteristics of esophageal motor activity responsible for the development of gastroesophageal reflux (GER) in patients with esophageal atresia (EA).

METHODS

The subjects consisted of 29 patients with EA (1 month to 19 years). Computerized esophageal manometry was conducted to investigate esophageal contractions at swallow. A topographic esophageal manometric analysis was conducted in each subject, providing 3-dimensional displays to reveal the pressure continuum representing esophageal contractions.

RESULTS

Significant contractions in the middle esophagus just below the anastomosis were absent in all subjects. Contractions in the distal esophagus were conspicuously absent in 17 subjects. Of these 17, 6 had already undergone fundoplication, and 9 had symptomatic GER requiring fundoplication subsequent to this study. The remaining 12 patients had contractions in the distal esophagus and did not require medical/surgical intervention. A lack of distal esophageal contractions was significantly correlated with the development of GER (P < .001). There was a significant difference in esophageal acid exposure between the 2 groups (median, 38% vs 4%, P < .001).

CONCLUSION

Lack of distal esophageal contractions indicating an impaired clearing capacity is considered a potential key determinant of GER in patients with EA.

Effects of rikkunshito on the clinical symptoms and esophageal acid exposure in children with symptomatic gastroesophageal reflux

Rikkunshito (TJ-43), a herbal medicine consisting of eight herbs, is used to treat chronic dyspepsia. Studies have shown that TJ-43 improves human gastric emptying. This study investigated the effects of TJ-43 on the clinical symptoms and esophageal acid exposure in children with symptomatic gastroesophageal reflux (GER). Eight children, aged from 2 months to 15 years (median age 4 years), were studied. Six of them had neurological impairment. TJ-43 (0.3 g/kg/day) was given orally or via nasogastric tubes in three divided doses before meals for 7 days. Their symptoms were frequent emesis in four, nausea in two, and hematemesis and stridor in one each. Twenty-four-hour esophageal pH monitoring was conducted using multichannel pH electrodes located at the distal esophagus (P1) and 10 cm proximal to P1 (P2). The clinical symptoms and esophageal pH were compared before and after TJ-43 therapy for 1 week. The frequency of emesis decreased in three patients. Other symptoms, including nausea, hematemesis, and stridor, were relieved in the remaining patients. Measured at the distal pH electrode, the percentage time of esophageal pH < 4.0 and the mean duration of reflux decreased significantly (P < 0.05). However, the number of acid reflux per hour did not change significantly, and no pH parameters measured at the proximal electrode differed significantly. The short-term administration of TJ-43 relieved symptoms and reduced the distal esophageal acid exposure through improved esophageal acid clearance.

Pediatric surgeons and gastroesophageal reflux

BACKGROUND/AIMS

Better antacid medications and the introduction of laparoscopy destabilize the indications for fundoplication. This study aims at raising a discussion among pediatric surgeons on these indications, modalities, and the results of this operation.

MATERIALS AND METHODS

A total of 252 refluxing children operated between 1992 and 2006 were divided into groups according to predominant symptoms (93 digestive, 47 respiratory, and 68 neurologic) or to comorbidities (27 esophageal atresia, 10 diaphragmatic hernia, 5 abdominal wall defects, and 2 caustic stricture), and the indications, complications, mortality, and long-term results were reviewed. Features of open (n = 135) and laparoscopic (n = 117) approaches were compared, and long-term integrity of the wrap was analyzed using the Kaplan-Meier method.

RESULTS

Digestive, respiratory, and neurologic patients had more often laparoscopic plications, whereas all others rather had an open approach. The rate of complications was 22%, and they were more frequent in children operated by laparotomy (P < .05). Median follow up was 51.3 months (range, 6-160). Overall wrap integrity was maintained in 89% of the children, and the proportions for digestive, respiratory, and neurologic groups were 95%, 95%, and 87%, respectively. For esophageal atresia, congenital diaphragmatic hernia, abdominal wall defects, and caustic stricture, they were 72%, 77%, 100%, and 0%, respectively. The functional results were fully satisfactory in 83% of patients. There were 17 deaths (6.7%), but only 3 in the first postoperative month and only 1 related to the operation (0.4%).

CONCLUSIONS

Fundoplication is a powerful method of reflux control. It is indicated after failure of medical treatment in gastroesophageal reflux disease and in symptomatic refluxers with some particular comorbidities. Surgery should be offered only after diagnosis has been firmly established, and the indications must remain identical for open and laparoscopic procedures. High technical standards and rigorous report of the results are required for keeping a relevant place of pediatric surgery in the treatment of this disease.

The contribution of elevated gastric pressure to prevention of gastroesophageal reflux in several different antireflux procedures

Although there are many studies evaluating the effect of elevated gastric pressure in total wrap and partial anterior and posterior wrap fundoplications, there are no ex vivo manometric studies evaluating the contribution of elevated gastric pressure to prevention of gastroesophageal reflux (GER) in Collis and uncut Collis procedures without fundoplication. An experimental study has been designed to determine the contribution of elevated intragastric pressure in the absence of in vivo anatomic and functional factors to the prevention of GER in Collis and uncut Collis without fundoplication procedures. The study was conducted on adult male New Zealand rabbits' esophagus and stomachs. The stomachs were divided into four groups: total wrap fundoplication group, partial wrap anterior fundoplication group, Collis without fundoplication group, and uncut Collis without fundoplication group. The minimum intragastric pressure (MIP) causing GER of each stomach before and after the procedure were measured with a two-way catheter introduced through the pylorus. The MIP values causing GER of the total wrap and partial anterior wrap fundoplication groups were found to be significantly higher compared with the basal intragastric pressures (P < 0.01). The MIP values causing GER of the Collis and uncut Collis without fundoplication groups were not significantly different compared with basal intragastric pressures (P > 0.05). The elevated gastric pressure is found to be insufficient to prevent GER in Collis and uncut Collis without fundoplication procedures. The efficacy of these procedures in preventing GER seems to be related to the anatomic and functional factors affecting in vivo circumstances.

Gastrointestinal complications of fundoplication

In children with medically refractory gastroesophageal reflux disease (GERD), fundoplication is effective and safe. However, in a subset of patients, gastrointestinal dysfunction occurs postoperatively. Symptoms include chest pain, persistent dysphagia in 5%, gas bloat in 2% to 4%, diarrhea in up to 20%, and dumping syndrome in up to 30%. Symptoms are often nonspecific, arising from recurrent or persistent GERD, anatomic complications such as disrupted or herniated wrap, functional disturbances such as rapid gastric emptying or altered gastric accommodation, or alternative diagnoses such as cyclic vomiting syndrome or food allergy. Detailed investigation, including various combinations of pHmetry, videofluoroscopy, endoscopy, motility studies, and dumping provocation testing, may be required to clarify pathophysiology and guide management.

The usefulness of videomanometry for studying pediatric esophageal motor disease

PURPOSE

Abnormalities in esophageal motor function underlie various symptoms in the pediatric population. Manometry remains an important tool for studying esophageal motor function, whereas its analyses have been conducted with considerable subjective interpretation. The usefulness of videomanometry with topographic analysis was examined in the current study.

METHODS

Videomanometry was conducted in 5 patients with primary gastroesophageal reflux disease (GERD), 4 with postoperative esophageal atresia (EA), 1 with congenital esophageal stenosis (CES), and 1 with diffuse esophageal spasms (DES). Digitized videofluoroscopic images were recorded synchronously with manometric digital data in a personal computer. Manometric analysis was conducted with a view of concurrent esophageal contour and bolus transit.

RESULTS

Primary GERD patients showed esophageal flow proceeding into the stomach during peristaltic contractions recorded manometrically, whereas patients with EA/CES frequently showed impaired esophageal transit during defective esophageal peristaltic contractions. A characteristic corkscrew appearance and esophageal flow in a to-and-fro fashion were seen with high-amplitude synchronous esophageal contractions in a DES patient. The topographic analysis showed distinctive images characteristic of each pathological condition.

CONCLUSIONS

Videomanometry is helpful in interpreting manometric data by analyzing concurrent fluoroscopic images. Topographic analyses provide characteristic images reflecting motor abnormalities in pediatric esophageal disease.

Effect of baclofen on emesis and 24-hour esophageal pH in neurologically impaired children with gastroesophageal reflux disease

OBJECTIVES

Gastroesophageal reflux disease (GERD) is difficult to control with medical therapy in neurologically impaired children. The gamma-aminobutyric acid type B receptor agonist baclofen was recently reported to reduce reflux in adult patients with GERD by reducing the incidence of transient lower esophageal sphincter relaxations. The current study was undertaken to investigate the effects of baclofen on GERD in neurologically impaired children.

METHODS

Eight neurologically impaired children with GERD between 2 months and 16 years were studied. Baclofen (0.7 mg/kg/day) was administered orally or via nasogastric tube in three divided doses 30 minutes before meals for 7 days. The frequency of emesis on and off baclofen were recorded as a measure of clinical impact. Twenty-four-hour esophageal pH monitoring was conducted before and on the seventh day of the administration of baclofen.

RESULTS

The frequency of emesis was significantly decreased (P = 0.03). The total number of acid refluxes was significantly decreased both during the entire 24-hour period (P = 0.01) and during the postprandial period (P = 0.049). The number of acid refluxes longer than 5 minutes was significantly decreased during the 24-hour period (P = 0.02). The percentage total time of esophageal pH <4.0 and esophageal acid clearance time were not significantly different during the 24-hour period or during the postprandial period. No adverse effects were observed, except for a slight reduction in muscle tone in one subject.

CONCLUSIONS

In this 1-week trial, repetitive administration of baclofen reduced the frequency of emesis and the total number of acid refluxes in neurologically impaired children with GERD.

Esophageal motor function in congenital esophageal stenosis

BACKGROUND/PURPOSE

Congenital esophageal stenosis (CES) is a rare condition that is associated with various foregut symptoms. The aim of the current study was to investigate esophageal motor function in pediatric patients with isolated CES.

METHODS

Four boys with CES (age, 3 weeks to 4 years old) were studied before treatment. The initial symptoms were dysphagia or stridor. The CES was caused by fibromuscular stenosis (FMS) in 2, tracheobronchial remnants (TBR) in 1, and membranous diaphragm (MD) in 1. An esophagram, endoscopy, 24-hour esophageal pH monitoring, and manometry were conducted.

RESULTS

The esophagram showed the stasis of contrast medium proximally to the distal esophageal narrowing in FMS/TBR patients. Endoscopic esophagitis was not found in any patients. Three patients were documented with pathologic esophageal acid exposure by 24-hour esophageal pH monitoring. Manometry showed that esophageal contractions predominantly were synchronous in FMS/TBR patients but were peristaltic in an MD patient. Basal lower esophageal sphincter (LES) pressure was at least 20 mm Hg in all. Swallow-induced LES relaxations were incomplete in FMS/TBR patients.

CONCLUSIONS

The presence of gastroesophageal reflux and impaired esophageal motility are common in patients with CES.

The histological appearances of Nissen-type fundoplication in the ferret

Nissen fundoplication is of proven effectiveness in the surgical control of gastro-oesophageal reflux. However, our understanding of the effects of fundoplication upon foregut physiology is incomplete and post-operative symptoms are often poorly understood. This experimental study aimed systematically to characterize the tissue response to fundoplication in an animal model, to improve understanding of the effects of anti-reflux surgery upon foregut physiology. Nissen-type fundoplication was performed in the ferret, and the tissue response at 3 months examined histologically. Sham-operated animals that underwent laparotomy but no dissection or wrap, acted as controls. In fundoplicated animals, serosal fibrosis was observed in the gut wall, with patchy replacement of muscle by fibrous tissue. The ventral and dorsal vagal nerve trunks were identified intact within the wrap. In cases where the wrap had spontaneously disrupted, fibrosis was more extensive and there was evidence of nerve damage. This is the first systematic description of the histopathological response to Nissen fundoplication. In the intact wrap, the vagal trunks appear spared, but there is fibrosis in the serosa, extending into the muscularis of the distal oesophagus and region of the cardia. These findings are discussed in relation to the effects of Nissen fundoplication upon gastric physiology and postoperative symptoms.

Laparoscopic fundoplication and gastrostomy

Minimally invasive surgical approaches to various pediatric surgical disease processes are becoming the standard of care. Laparoscopic Nissen fundoplication is transitioning toward the preferred method for the surgical correction of gastroesophageal reflux (GER) disease in infants and children that do not respond to medical management or have complications from their GER. This approach offers a shorter hospitalization, reduced discomfort, and cosmetic advantages when compared with the open operation. This report discusses the pathophysiology of GER, its clinical manifestations, and the diagnostic evaluation for this disorder. Also, the laparoscopic Nissen fundoplication technique currently utilized at Children's Mercy Hospital is described.

Mechanisms of gastroesophageal reflux and gastroesophageal reflux disease

Gastroesophageal reflux is a physiological phenomenon, occurring with different severity and duration in different individuals. Reflux occurs when this normal event results in the occurrence of symptoms/signs or complications. The pathophysiology of gastroesophageal reflux is complex and diverse, since it is influenced by factors that are genetic, environmental (e.g., diet smoking), anatomic, hormonal, and neurogenic. However, many mechanisms remain incompletely understood. Future research should focus on a better understanding of the physiology of the upper and lower esophageal sphincters, and of gastric motility. The afferent and efferent neural pathways and neuropharmacologic mediators of transient lower esophageal sphincter relaxations and gastric dysmotility require further study. The role of anatomic malformations such as hiatal hernia in children has been underestimated. While therapeutic possibilities are greater in number and largely improved, the outcomes of some treatments are far from satisfactory in many cases. In addition to development of new forms of treatment, research should address better use of currently available medical and surgical treatments.

Postfundoplication Complications in Children

The optimal "treatment" of postfundoplication complications is preoperative prevention of them. Nonreflux causes of the symptom prompting surgery should be carefully eliminated preoperatively. Failure to respond to optimal powerful antireflux pharmacotherapy suggests that GERD was not the cause of symptoms. Neurologic or respiratory disease, delayed gastric emptying or retching, short esophagus, and esophageal dysmotility may predispose patients to complications, and may require careful tailoring of the fundoplication. The optimal antireflux surgery, with a wrap neither too loose nor too tight, may require a nadir lower esophageal sphincter pressure of more than 5 mm Hg to prevent reflux, but less than some value to prevent dysphagia. This latter value may be approximately 10 mm Hg, but depends on swallowing parameters such as peristaltic pressure, lower esophageal sphincter opening diameter, swallowed bolus diameter, and other considerations. Infants may require a gastrostomy tube for venting because of their lower gastric compliance to deal with swallowed air. Children with delayed gastric emptying may benefit from pyloroplasty, but this is debated. When complications occur, re-evaluate the diagnosis and the competence of the fundoplication with barium fluoroscopy, endoscopy with histology, pH probe, and other modalities as indicated. Initially try conservative management of the patient's complications, including dietary and feeding modifications. Give a trial of antireflux pharmacotherapy for recurrent reflux or pharmacotherapy directed at the specific side-effect of the fundoplication if one is present. Consider endoscopically dilating a persistently tight wrap or surgically revising the fundoplication if it is suggested by the evaluation.

Relationship between straining, transient lower esophageal sphincter relaxation, and gastroesophageal reflux in children

OBJECTIVE

Physical straining such as deep inspiration or coughing may induce gastroesophageal reflux (GER) by overcoming feeble lower esophageal sphincter (LES) pressure. The role of straining as a provocant of GER has not been analyzed systematically in children. It was our aim to examine the contribution of straining to the occurrence of GER with particular attention to its relationship to transient LES relaxations, which are a major mechanism of the occurrence of GER in pediatric patients.

METHODS

Concurrent esophageal manometry and pH monitoring was performed for 4 h postprandially in six children with esophagitis (age 9 months to 12 yr). Analysis was performed on isolated single strain episodes, defined as an increased intragastric pressure > 10 mm Hg. When a drop of esophageal pH < 4.0 was noted within 15 sec after any part of a strain, this strain was defined as related to the reflux episode.

RESULTS

The median value of basal LES pressure was 10 mm Hg (range 1-18). In all, 134 analyzable strains and 87 analyzable reflux episodes were recorded. Isolated strains were associated with 20 reflux episodes (23%). Reflux was observed more frequently with strains that occurred during transient LES relaxations (12/40) than straining when the LES was contracted (8/94) (p < 0.01). Sustained strain (35%) and inspiratory strain (25%) were the major patterns of straining related to reflux.

CONCLUSION

Straining provoked reflux infrequently and simultaneous occurrence of straining and transient LES relaxation was important in determining the occurrence of strain-related reflux in pediatric patients with reflux esophagitis.

Motor function of the esophagus and the lower esophageal sphincter in children who undergo laparoscopic nissen fundoplication

BACKGROUND/PURPOSE

To define the clinical role of laparoscopic Nissen fundoplication (LNF) in children with gastroesophageal reflux (GER), an appropriate understanding of its functional effects is required. The aim of this study was to investigate the motor function of the esophageal body and the lower esophageal sphincter (LES) with special reference to the effects of caloric nutrients in children undergoing LNF.

METHODS

Studies were performed in 12 children with GER (age, 6 months to 13 years) before and a month after LNF. Continuous manometric examination was performed with an infusion system using a sleeve sensor for an hour each before and after the administration of apple juice (AAJ; 10 mL/kg).

RESULTS

AAJ increased postoperative basal LES pressure from 15 +/- 7 to 20 +/- 6 mm Hg, whereas it decreased the preoperative values from 13 +/- 5 to 10 +/- 4 mm Hg (P < .05). Significant residual pressure was noted at the nadir of swallow-induced LES relaxation after LNF, which was increased by AAJ from 7 +/- 3 to 11 +/- 4 mm Hg. A child with a high nadir LES pressure showed postoperative dysphagia. Significant changes in the patterns of esophageal contractions were not noted after LNF.

CONCLUSIONS

Characteristics of the effect of LNF on the LES were a postprandial increase of basal LES pressure and significant residual LES pressure at the nadir of LES relaxation. The motor function of the esophageal body was not affected by LNF.

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.