Esophageal pH-MII Duration: 12 or 24 Hours?

Study Overview
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Brief Summary
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To check whether the first 12 hours of MII-pH recording are sufficient to diagnose gastroesophageal reflux disease (GERD) among newborns/infants, with a diagnostic accuracy similar to 24 hours of recording as currently advised.

Detailed Description
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The results of the 24 hour MII-pH recording will be compared to those from the first 12 hour of the same study. To this end the study investigators will select the first 12 hour of the recording using the manufacturer's software (Diversatek Zvu Advanced GI Diagnostic Software). Published normal reference values will be used to confirm gastroesophageal reflux (GER). Appropriate statistical methods will be used to perform calculations. Subgroup analyses based on preterm birth, presence of bronchopulmonary dysplasia and type of prevalent GER symptom (respiratory or gastrointestinal) will be performed.

Official Title
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Duration of Esophageal pH-impedance Measurement in Newborns and Infants With Suspected Gastroesophageal Reflux: 12 or 24 Hours?

Conditions
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Gastro Esophageal Reflux

Intervention / Treatment
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* Diagnostic Test: multichannel intraluminal impedance and pH monitoring (MII/pH)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 24 hours MII-pH performed for suspected GER Exclusion Criteria: major malformations previous thoraco-abdominal surgery, gastrostomy, anti-GERD therapy (thickeners, alginates, H2 blockers, proton pump inhibitor - PPIs, etc.) in the 7 days preceding the MII-pH, ventilatory support (invasive or non-invasive) at the time of the MII-pH

Ages Eligible for Study
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Minimum Age: 1 Day
Maximum Age: 12 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: multichannel intraluminal impedance and pH monitoring (MII/pH)|A pH-MII probe is inserted nasally into the esophagus, and the position verified by chest radiograph. pH-MII data are evaluated using manufacturer's software, and each tracing is manually reviewed and validated.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of GER episodes | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| number of GER episodes reaching the proximal esophagus | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| time with pH<4 | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| bolus exposure index | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| bolus clearance time | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| symptom index | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| symptom association probability | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of GER episodes: subgroup analysis based on gestational age at birth, diagnosis of bronchopulmonary dysplasia (BPD), prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| number of GER episodes reaching the proximal esophagus: subgroup analysis based on gestational age at birth, diagnosis of BPD, prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| time with pH<4: subgroup analysis based on gestational age at birth, diagnosis of BPD, prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| bolus exposure index: subgroup analysis based on gestational age at birth, diagnosis of BPD, prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| bolus clearance time: subgroup analysis based on gestational age at birth, diagnosis of BPD, prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| symptom index: subgroup analysis based on gestational age at birth, diagnosis of BPD, prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software. Range 0-100% (values ≥ 50% are significant). | comparison between the first 12 hours of the test and the whole duration (24 hours) | 
| symptom association probability: subgroup analysis based on gestational age at birth, diagnosis of BPD, prevalent symptoms (respiratory or gastrointestinal) | As detected by manufacturer's software. Range 0-100% (values ≥ 95% are significant). | comparison between the first 12 hours of the test and the whole duration (24 hours) |