Significance of Gastroesophageal Refluxate in Relation to Physical Chemical and Spatio-temporal Characteristics in Symptomatic ICU Neonates

摘要

GERD (gastroesophageal reflux disease) is a frequent consideration in ICU neonates. We tested the hypothesis that symptoms in GERD are dependent on the spatio-temporal and physico-chemical characteristics of reflux events by evaluating the symptom sensitivity index (SSI) and symptom index (SI) in relation to the refluxate characteristics. Thirty symptomatic neonates (30.7±0.8 wk gestation) were evaluated using manometry and pH-Impedance methods. During 704.3 hr of recordings, 2,063 GER (gastroesophageal reflux) were observed; 54% of the GER were associated with symptoms. Defined by physical characteristics, there were 51.3% liquid, 29.1% gas, and 19.6% mixed GER. Defined by chemical characteristics, there were 48.5% acid- and 51.5% non-acid GER. Defined by most proximal extent, 79.2% were supra-UES (upper esophageal sphincter), 20.8% were infra-UES. Higher SSI was noted with pH-only events (P<0.0001 vs. pH-Impedance events). Higher SI was noted with movement symptoms (vs. sensory, P=0.04). In a subset analysis, the frequencies of GER events, acid clearance time, and SSI were all greater in chronic lung disease vs. none (P<0.001). In conclusion, clinical significance of symptoms as measured by SSI and SI and characterization of spatial-temporal-physical-chemical nature of GER events as defined by pH-impedance methods clarifies the definition of GERD.