Reproducibility of 24 hour oesophageal pH studies in infants

Cisapride treatment for gastro-oesophageal reflux in children

BACKGROUND

Gastro-oesophageal reflux (GOR) is common and usually self-limiting in infants. Cisapride, a pro-kinetic agent, was commonly prescribed until reports of possible serious adverse events were associated with its use.

OBJECTIVES

To determine the effectiveness of cisapride versus placebo or non-surgical treatments for symptoms of GOR.

SEARCH STRATEGY

We searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Specialised Register and Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE, reference lists of relevant review articles and searched in the Science Citation Index for all the trials identified. All searches were updated in February 2009.

SELECTION CRITERIA

Randomised controlled trials comparing oral cisapride therapy with placebo or other non-surgical treatments for children diagnosed with GOR were included. We excluded trials with a majority of participants less than 28 days of age.

DATA COLLECTION AND ANALYSIS

Primary outcomes were a change in symptoms at the end of treatment, presence of adverse events, occurrence of clinical complications and weight gain. Secondary outcomes included physiological measures of GOR or histological evidence of oesophagitis. We dichotomised symptoms into 'same or worse' versus 'improved' and calculated summary odds ratios (OR). Continuous measures of GOR (for example reflux index) were summarised as a weighted mean difference. All outcomes were analysed using a random-effects method.

MAIN RESULTS

Ten trials in total met the inclusion criteria. Nine trials compared cisapride with placebo or no treatment, of which eight (262 participants) reported data on symptoms of gastro-oesophageal reflux. There was no statistically significant difference between the two interventions (OR 0.34; 95% CI 0.10 to 1.19) for 'same or worse' versus 'improved symptoms' at the end of treatment. There was significant heterogeneity between the studies, suggesting publication bias. Four studies reported adverse events (mainly diarrhoea); this difference was not statistically significant (OR 1.80; 95% CI 0.87 to 3.70). Another trial found no difference in the electrocardiographic QTc interval after three to eight weeks of treatment. Cisapride significantly reduced the reflux index (weighted mean difference -6.49; 95% CI -10.13 to -2.85; P = 0.0005). Other measures of oesophageal pH monitoring did not reach significance. One included study compared cisapride with Gaviscon (with no statistically significant difference). One small study found no evidence of benefit on frequency of regurgitation or weight gain after treatment with cisapride versus no treatment, carob bean or corn syrup thickeners.

AUTHORS' CONCLUSIONS

We found no clear evidence that cisapride reduces symptoms of GOR. Due to reports of fatal cardiac arrhythmias or sudden death, from July 2000 in the USA and Europe cisapride was restricted to a limited access programme supervised by a paediatric gastrologist.

Laryngopharyngeal Reflux: Trends in Diagnostic Interpretation Criteria

Laryngopharyngeal reflux (LPR) is becoming recognized as a clinical entity with a variety of presentations distinct from those of gastroesophreflux disease (GERD). However, much uncertainty remains as to what is considered pathologic versus physiologic reflux. The aim of the study was to determine the normal range of pharyngeal reflux (PR) occurring in healthy adults based on pH-monitoring parameters utilized in the DeMeester scoring system for GERD. We have reviewed the current pool of prospective literature examining ambulatory dual-channel pH-monitoring study data derived from hypopharyngeal proximal probes in normal adults. From our review we have identified trends in several monitoring parameters based on the DeMeester scoring system for GERD. Our discussion recognizes and accepts the limitations imposed by small sample sizes and the number of healthy individuals that would be required to determine the general adult physiologic range of PR. We also explore the possible need for separate normal PR reference intervals based on age or gender disparities. Additional discussion and the summary address future directions for LPR research notably, (1) identification of the most appropriate research paradigm for LPR (i.e., pH 4 vs. 5), (2) establishing reproducibility for the appropriate LPR research paradigm, and (3) complementary modalities to ambulatory dual-channel pH monitoring for the study of acid and nonacid bolus movement within the esophagus

Low reproducibility of 2 x 24-hour continuous esophageal pH monitoring in infants and children: a limiting factor for interventional studies

The aim of this study was to investigate the day-to-day reproducibility of 24-hr esophageal pH monitoring. The procedure was performed continuously for 48 hr in order to enable future studies on dietary challenges, using consecutive 2 x 24 hr pH recording. Furthermore, one objective was to relate the degree of reproducibility to endoscopic evidence of mucosal injury. Upper endoscopy and 2 x 24-hr consecutive pH monitoring were performed in 30 infants and children referred for gastroesophageal reflux disease. The monitoring was performed without dietary or activity restrictions in order to assess reflux parameters in a near-normal physiologic setting. The NASPGHAN criteria for pathological reflux index (RI, % fraction of time with pH < 4.0) were employed. Based upon the NASPGHAN criteria for the RI, 9/30 subjects (30%) had discordant (normal vs pathologic) results at the two recording days, yielding an overall reproducibility of 70%. The limits of agreement for RI at day 2 were 0.2-3.3 times the initially obtained value at day 1. No difference was found in terms of reproducibility between groups with and without esophageal mucosal changes (erythema and esophagitis). No significant difference was noted in the association between pH monitoring and macroscopic esophageal mucosal changes between the two recordings days. In conclusion, a considerable intraindividual variability in reflux parameters was observed between the measurements from day 1 to day 2. This physiologic variability should be taken into consideration when evaluating gastroesophageal reflux disease in infants and children by means of pH monitoring. The day-to-day variability limits the use of simultaneous pH monitoring and dietary challenges as a procedure to identify a possible causative relation between GERD and dietary allergy/intolerance.

Cisapride treatment for gastro-oesophageal reflux in children

BACKGROUND

Gastro-oesophageal reflux (GOR) is an extremely common and usually self-limiting condition in infants. When treatment is required, Cisapride, a pro-kinetic agent, has been commonly prescribed for the symptomatic management of GOR. There have been recent reports of possibly serious adverse events, e.g. an increased QTc interval, cardiac arrhythmias, and death, associated with the use of Cisapride.

OBJECTIVES

To determine the effectiveness of Cisapride for symptoms of GOR compared with placebo or any other non-surgical treatments.

SEARCH STRATEGY

Searches were conducted of the Cochrane Central Trials Register and the specialised Trials register of the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group, MEDLINE and Embase up till April 2002. Reference lists of relevant review articles and identified trials were scrutinised and forward citation searches were performed in the Science Citation Index on all trials identified. The search was re-run in August 2003 and no new trials were found.

SELECTION CRITERIA

Randomised controlled trials that compared oral Cisapride therapy with placebo or with other non-surgical treatments for children with a diagnosis of GOR were included. Only studies in which Cisapride was administered orally for a minimum of one week and which documented at least one of the primary outcomes were included. We excluded trials in which the majority of participants were aged less than 28 days.

DATA COLLECTION AND ANALYSIS

The primary outcomes were defined as a change in symptoms at the end of treatment, presence of adverse events, occurrence of clinical complications, and weight gain. The secondary outcomes included physiological measures of GOR or histological evidence of oesophagitis. We dichotomised symptoms into 'same or worse' vs 'improved' and calculated summary odds ratios. Continuous measures of GOR (e.g. reflux index) were summarised as a weighted mean difference. All outcomes were analysed using a random effects method.

MAIN RESULTS

Searches identified nine trials which met the inclusion criteria. Eight trials compared Cisapride with placebo, of which seven (236 participants) reported data on symptoms of gastro-oesophageal reflux, and one reported data on the QTc interval (49 patients). The odds ratio for 'same or worse' vs 'improved symptoms' at the end of treatment of 0.34 (95%CI 0.10, 1.19) did not show a statistically significant difference between the two interventions. There was significant heterogeneity between the studies and the funnel plot suggested publication bias. In a sensitivity analysis, the definition of outcomes was changed to 'any symptoms' vs 'no symptoms'. This resulted in the exclusion of three trials (one of them the largest, best quality trial). The resulting pooled odds ratio showed a significant effect of Cisapride (OR 0.19, 95%CI 0.08, 0.44). Five studies reported adverse events. Four reported adverse events (mainly diarrhoea) but the difference was not statistically significant (OR 1.80, 95%CI 0.87, 3.70). One trial found no difference in the QTc after 3 to 8 weeks of treatment. Cisapride was associated with a statistically significant reduction in the reflux index (weighted mean difference -6.49, 95%CI -10.13, -2.85), but as reflux index and clinical symptoms are poorly correlated, the clinical importance of this finding is uncertain. Other measures of oesophageal pH monitoring did not reach significance. One included study compared Cisapride with Gaviscon (or Gaviscon and Carobel). The odds ratio for 'same or worse' vs 'improvement' in the Cisapride group compared with Gaviscon was 3.26 (95%CI 0.93-11.38).

REVIEWER'S CONCLUSIONS

We found no clear evidence that Cisapride reduces symptoms of GOR. The results suggested substantial publication bias favouring studies showing a positive effect of Cisapride. This finding is supported by the report of one unpublished multi-centre study of 134 patients, which was reported to show no evidence of a significant effect of Cisapride. Due to reports of fatal cardiac arrhythmias or sudden death, from July Due to reports of fatal cardiac arrhythmias or sudden death, from July 2000, cisapride was restricted to a limited access programme supervised by a paediatric gastrologist in the USA and in Europe, to patients treated within a clinical trial or safety study or registry programme.

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.

The role of gastro-oesophageal reflux in the aetiology of SIDS

Gastro-oesophageal reflux (GOR) has been identified as a possible cause of SIDS. Several features of GOR unique to infants presenting with apparent life-threatening events (ALTEs) have led to its 'pathogenic' definition. One is that the life-threatening apnoea itself is initiated by GOR, another is that the ALTE relates to prolonged reflux during sleep, in a vulnerable sleep-state, and finally that the ALTE relates to excessive quantities of GOR. The presumption of GOR 'pathology' as a cause of SIDS however, is questionable in these susceptible infants for three reasons: firstly, GOR is physiological and occurs in most infants; secondly, there is no general consensus on what constitutes normal physiological reflux, and thirdly, variation in the recording technique and methods of data analysis and interpretation may account for the differences between study groups. It seems likely therefore if GOR is implicated in SIDS, additional factors are involved. Under certain circumstances, physiological GOR may trigger life-threatening apnoea in apparently healthy infants, that leads to SIDS. One mechanism that could explain such a death is reflex apnoea by stimulation of laryngeal chemoreceptors (LCR) during sleep. The conditions under which this could be fatal are the occurrence of gastric contents refluxed to the level of the pharynx during sleep, in the young infant who has depressed swallowing and arousal. That is, the occurrence of GOR to the level of the pharynx during sleep, an infrequent event that is usually innocuous, could be converted to a fatal event if swallowing is impaired and arousal depressed, by a variety of mediating factors such as prone sleeping, prematurity, sedatives, seizures or upper respiratory tract infections. The identification of LCR responses, particularly in prone sleeping and premature infants provide further evidence that this mechanism may be implicated in the aetiology of SIDS in apparently healthy infants.

Enteral feeding in the preterm infant

In planning enteral feeding in the preterm infant, decisions need to be made regarding the feeding schedule, choice of milk, and the route of administration. Feeds should be commenced within a week after birth beginning with subnutritional quantities. Preterm human milk from the infant's own mother is the milk of choice. When full enteral feeding is established, supplementation with human milk fortifier is recommended. Donor human milk and preterm formula are alternatives. Early establishment of enteral nutrition and maintenance of optimal nutrition during infancy are important as dietary manipulations in preterm infants have potential long-term influences on their health, growth and neurodevelopment.

Histological esophagitis: clinical and histological response to omeprazole in children

Many children with esophagitis demonstrate histological changes without gross evidence of esophagitis by esophagoscopy. The effect of omeprazole on the histological healing of esophagitis in children is unknown. Therefore, the aim of this study was to determine the effect of omeprazole on refractory histological esophagitis in pediatric patients. Eighteen patients with histological evidence of esophagitis and recurrent symptoms despite therapy with H2-receptor antagonists and prokinetic agents were prospectively treated with omeprazole. Dosing was adjusted by monitoring intragastric pH, and esophagoscopy was repeated after 8-12 weeks of omeprazole treatment. Two patients did not complete the study due to either worsening symptoms or hypergastrinemia. Of the remaining patients, 76% were asymptomatic with omeprazole treatment and 24% reported improvement in their symptoms. Approximately 40% demonstrated complete histological healing of their esophagitis. Three patients (17%) had persistent elevations in serum gastrin levels while on omeprazole treatment, which was associated with both younger patient age and higher omeprazole dosing; however, all elevated gastrin levels returned to normal after discontinuation of the medication. All patients had recurrence of their symptoms after completing a course of omeprazole, even patients with complete histological healing. Omeprazole is efficacious in treating children with esophagitis refractory to H2-receptor antagonist and prokinetic agents. However, none of the patients were able to discontinue acid suppressive therapy even after documented healing of their esophagitis.

Late follow-up in patients with gastroschisis : Gastroesophageal reflux is common

During a 16-year period, 60 neonates with gastroschisis were treated at the Department of Pediatric Surgery in Graz; 6 died and 54 (90%) survived. A questionnaire was sent to 45 patients, who were called for a medical examination; 31 patients (69%) came to follow-up, 26 of whom reported minor abdominal problems that could be related to gastroesophageal reflux (GER). Fifteen agreed to 24-h esophageal pH monitoring and/or upper gastrointestinal series; in 7 pathological GER could be demonstrated. Manometric studies in 6 patients revealed a motility disorder of the esophagus. Only 4 children were concerned by a disfiguring scar or the absence of a navel. Heigtt and weight were within normal limits and the children had developed normally.

Reproducibility of ambulatory esophageal pH monitoring in the aperistaltic esophagus

The reproducibility of ambulatory 24-h esophageal pH monitoring was evaluated in 16 consecutive patients by comparing the difference in two consecutive 24-h periods. The study group included 8 patients with scleroderma esophagus and 8 treated achalasia patients. The amount of reflux was expressed as the percentage of time the pH was < 4.0. Both groups demonstrated excellent intrapatient reproducibility overall: 96% in scleroderma patients and 95% in those patients with achalasia. The least concordance was found in the lengths of the longest reflux events-70% when supine in scleroderma patients and 59% when upright in patients with achalasia. There was no significant difference (p > 0.05) between day 1 and day 2 for either group of patients for any of the elements studied. These results indicate that intrapatient variability of gastroesophageal reflux in patients with scleroderma esophagus and treated patients with achalasia is very low and following therapeutic intervention, a high level of confidence can be placed in subsequent pH monitoring as an indicator of treatment effect.

Effect of general anaesthesia on prolonged intraoesophageal pH monitoring

Investigation of gastro-oesophageal reflux often includes endoscopy, usually under general anaesthesia, and pH monitoring. In most cases, the pH probe is passed when the child is awake and is poorly tolerated. The effect of general anaesthesia on pH monitoring is unknown. The aim of the study was to determine if placing the probe in the anaesthetised child gives a representative pH study. Twenty children aged 4 months to 13 years underwent oesophago-gastroduodenoscopy under general anaesthesia. A pH electrode was placed under direct vision in the distal oesophagus. pH monitoring was begun after completion of anaesthesia and continued for 18-24 hours. The study was repeated within 14 days without anaesthetic. The reproducibility of values of percent pH < 4, number of reflux episodes/hour, reflux episodes lasting > 5 min, and longest reflux episode was 85%, 90%, 75%, and 75% respectively. These results are comparable with those in adults and children in whom pH studies were performed on consecutive days (without anaesthetic) keeping all variables constant. Therefore pH data collected in a child within 24 hours of endoscopy under general anaesthesia are representative.

Risks and benefits of antireflux operations in neurologically impaired children

Gastro-oesophageal reflux (GER) in neurologically impaired children often causes feeding problems and complications of oesophagitis and is frequently resistant to medical treatment. Fifty neurologically impaired children underwent anterior gastropexy as anti-reflux operation, combined with gastrostomy in 23, between 1976 and 1992. There was no operative mortality. There were 25 early complications in 14 patients and 9 late complications in 9 patients. Twelve patients needed 17 re-operations for delayed gastric emptying [4], intestinal obstruction [3], para-oesophageal hernia [3], oesophageal stenosis [4], and recurrent GER, revision of gastrostomy, subphrenic abscess (one each). Nine patients died during the follow up period. Death in two children was related to the operation (incarcerated para-oesophageal hernia and blow-out of the stomach). Out of 41 survivors, the operation was judged successful in 35. It is concluded that antireflux operations in neurologically impaired children carry a high risk of complications. Preoperative identification of risk factors is not possible. The improvements in the quality of life achieved in the majority of patients outweigh the risks.

Gaviscon and Carobel compared with cisapride in gastro-oesophageal reflux

We compared the efficacy of the prokinetic agent cisapride with that of Gaviscon (an alginate/alkaline compound) plus Carobel (carob seed flour) in the treatment of gastrooesophageal reflux (GOR). Fifty infants with confirmed GOR received either oral cisapride (0.8 mg/kg/day) or Gaviscon plus Carobel for one month in a randomised, parallel group study. Parental evaluations, diary scores, and 24 hour lower oesophageal pH recordings before and at the end of each treatment were compared. In the cisapride group 14/26 (53%) were considered better by their parents compared with 19/24 (79%) of those who received Gaviscon plus Carobel. Diary scores, range (0.00-1.00), improved in both groups with the median change being greater in the Gaviscon plus Carobel group (-0.21) than the cisapride group (-0.15). Five of 17 pH variables had significantly improved from baseline in infants who had received cisapride compared with 11/17 in those receiving Gaviscon plus Carobel. However, unpaired analysis of diary and pH data showed no significant differences between the two groups. We conclude that first line treatment of GOR with cisapride is no more effective than conventional treatment with Gaviscon plus Carobel.

Variations in results of simultaneous ambulatory esophageal pH monitoring

Twenty-four-hour esophageal pH monitoring is regarded as the gold standard investigation for gastroesophageal reflux (GER) (1) and the possibility of an "incorrect" answer, false positive or false negative, is only rarely considered (2). However, when a group of infants in this hospital had such pH studies performed on two consecutive days, considerable differences in the results were found (3). This also had been reported from other centers (4-6). It seems likely that most of the differences were due to true "biological" variability in the amount of GER from day to day, but it remains possible that variation in the accuracy of the equipment in detecting acid reflux was also involved.

Lack of temporal relation between acid reflux in the proximal oesophagus and cardiorespiratory events in sleeping infants

We studied sleeping infants in order to investigate whether a temporal relation exists between acid reflux extending to the proximal portion of the oesophagus and cardiorespiratory events. One hundred infants with occasional regurgitations were studied: 50 infants admitted after an apparently life-threatening event (ALTE) that occurred during sleep and that remained unexplained despite medical investigation, and 50 asymptomatic infants (non-ALTE). The infants had a median age of 8 weeks (range 4-26 weeks); 54 were boys. In each child a pH probe was placed in the proximal portion of the thoracic oesophagus, under radiological control. Polygraphic monitoring of state of alertness, cardiorespiratory activity, and proximal oesophageal pH changes was conducted continuously during 1 night. The data were analysed blind. In 80 infants a total of 186 decreases in oesophageal pH below 4 units were seen; 37% occurred during wakefulness, and 40% during rapid eye movement (REM) sleep. A total of 7029 central and 61 obstructive apnoeas were monitored, mainly during REM sleep. Within 5 min before, and 5 min after the drops in pH, there was no difference in the number, or the duration of bradycardia, central, mixed, or obstructive apnoea. The infants with an ALTE could not be differentiated from the non-ALTE infants for any of the variables studied. It is concluded that spontaneous acid refluxes extending to the proximal portion of the oesophagus during sleep are usually not temporally related with the development of apnoeas or bradycardias.

Impact of sleep and movement on gastro-oesophageal reflux in healthy, newborn infants

Seventy four normal, healthy newborn babies were studied to examine the relationship between gastro-oesophageal reflux, sleep state, and movement. Multichannel pen recordings were made to determine sleep state, movement, breathing, and reflux. The mean number of reflux episodes per hour was highest in wakefulness, followed by active and indeterminate sleep. In quiet sleep reflux rarely occurred. The mean duration of reflux episodes per hour was longest in active sleep followed by wakefulness, indeterminate and quiet sleep. There was a strong positive correlation between duration of reflux and movement time for wakefulness, active and indeterminate sleep. Movement preceded 88% of all reflux episodes. Physiological reflux occurs in most newborn infants but is clinically inapparent. The results suggest that state and movement are related to the incidence and duration of reflux. Sleep state is therefore an important variable in determining normal values for reflux in infancy since developmentally the amount of sleep time lessens but quiet sleep proportionally increases.

Gastro-oesophageal reflux in mechanically ventilated preterm infants

Long duration oesophageal pH recordings were performed on 42 mechanically ventilated and parenterally fed preterm infants for a mean (SD) of 94 (28) hours. Their mean (SD) gestational age was 31.5 (2.6) weeks and birth weight 1514 (448) g. Their mean postnatal age was 19 (10) hours at the onset of pH recording, which was performed with the babies supine. The mean hourly values for the total number of episodes of gastro-oesophageal reflux (GOR) was 2.3 (2.7), for acid GOR 1.2 (1.4), and for acid GOR longer than 5 minutes 0.08 (0.09). The time the pH was greater than 4 (the reflux index) was 3.5 (3.3)% and the mean airway pressure was 6.6 (5.1) cm H2O. Fifteen infants had a reflux index above 5%. GOR patterns were not significantly correlated to birth weight, gestational age, postconceptional age, ventilatory patterns, and duration of mechanical ventilation. We concluded that the reproducibility of the reflux index was low because the median of the absolute differences was 1% when two consecutive 12 hour periods were compared and reached 2.5% when the two periods were separated by 96 hours. A second 24 hour pH recording was performed in 30 of the 42 patients after weaning from the ventilator and at a time when patients were asymptomatic and enterally fed. Compared with the late postprandial period of the second pH recording, the first recording showed an increase in the number of episodes of GOR and a decrease in reflux index, without any difference in the number of episodes of acid GOR.