Acute oxygen desaturation characterizes pulmonary aspiration in patients with gastroesophageal reflux disease and laryngopharyngeal reflux.

The aim of this study was to characterise pulmonary aspiration of refluxate in patients with gastroesophageal reflux disease (GORD) and laryngopharyngeal reflux (LPR) by continuous pulse oximetry (SpO2) during the supine phase of a scintigraphic reflux study. Variables assessed for significance included age, hiatus hernia, frequency, amplitude of reflux and clearance of reflux from the oesophagus/pharynx. The patients included in this study had established GORD and LPR by clinical history. All patients underwent fused three- dimensional scintigraphic/ X-ray computed tomography (CT) and simultaneous continuous pulse oximetry when supine for 30 minutes. A total of 265 patients (40.4% M, 59.6% F) were studied. Mean age of aspirators was 57.0 years and non-aspirators was 53.5 years. Seven patients had baseline oxygen saturation <95%, with 6/7 showing aspiration by scintigraphy. The remainder had mean baseline saturation of 97.7%. Continuous SpO2 monitoring showed a significant fall in pulmonary aspirators after 20 min of supine acquisition with significant variability. Analysis revealed a cyclic event every 1.5 min in aspirators only. Panel regression analysis showed a significant effect of age, hiatus hernia, pulse rate and reflux frequency on the fall in SpO2. Pulmonary aspiration in patients with LPR and GORD is characterised by acute oxygen desaturation. Variables affecting oxygen desaturation were age, hiatus hernia, pulse rate and reflux frequency. A cyclic event was observed every 1.5 min in aspirators and may be due to reflex homeostatic mechanism attempting to correct perceived hypoxia.