title: Temporal association of polysomnographic cardiorespiratory events with GER detected by MII-pH probe in the premature infant at term.
abstract: OBJECTIVE
  The aim of the study was to examine temporal association (TA) between polysomnographic cardiorespiratory (CR) events and gastroesophageal reflux (GER) in premature infants with persistent CR events at >39 weeks postmenstrual age and determine whether the use of multichannel intraluminal impedance (MII)-pH probe improves sensitivity of the TA compared with pH probe alone.
  
  
  METHODS
  Seven infants born between 24 and 29 weeks' gestational age with persistent CR events at 39 to 48 weeks' postmenstrual age underwent a polysomnography with MII-pH probe. Symptom index (SI) and symptom-associated probability were calculated for diverse types of reflux and CR events. SI and a Fisher exact test with variable association windows were calculated for obstructive apnea (OA). Odds ratios for an OA given a reflux event and for a reflux event given an OA were determined.
  
  
  RESULTS
  With a Fisher exact test, a subject-specific association between MII events and OA was found in the 3 patients who required a fundoplication or had the worse clinical GER. Some level of TA was found with SI and symptom-associated probability in 6 of 7 infants. Association was found for pH > 4 and pH ≤ 4 reflux events. pH-only events with no change of MII had only a limited role in generating CR events.
  
  
  CONCLUSIONS
  TA between CR events and GER was found in a single-subject-level analysis in some infants with persistent CR events at term. This TA suggests a causal relation between CR and reflux events that was further strengthened by the clinical outcomes of each infant.
authors.affiliation: Department of Pediatrics, Neonatology, Johns Hopkins Hospital and School of Medicine, Baltimore, MD 21224-2780, USA. jnunez4@jhmi.edu
authors.forename: Jeanne
authors.initials: J
authors.lastname: Nunez
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Cristofalo
authors.forename: Brian
authors.initials: B
authors.lastname: McGinley
authors.forename: Richard
authors.initials: R
authors.lastname: Katz
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Glen
authors.forename: Estelle
authors.initials: E
authors.lastname: Gauda
mesh_terms: D001049:Apnea / Q000150:complications* / Q000503:physiopathology; D017097:Electric Impedance; D050782:Esophageal pH Monitoring; D018662:Fundoplication; D005764:Gastroesophageal Reflux / Q000150:complications* / Q000503:physiopathology / Q000601:surgery; D005865:Gestational Age; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000503:physiopathology* / Q000601:surgery; D016017:Odds Ratio; D010992:Plethysmography, Impedance / Q000379:methods