Solid versus liquid pulmonary micro-aspiration of reflux disease. Does it make a difference in determining the need for intervention?

Background: Pulmonary micro-aspiration (PMA) is a feared complication of gastroesophageal reflux disease (GORD). A novel scintigraphic test for GORD has been developed and validated. It can demonstrate contamination of the upper and lower airways by refluxate. Current observations have led to the hypothesis that prolongation in solid gastric emptying (SGE) is crical in pulmonary micro-aspiration.

Methods: Standard LGE and SGE studies and the novel reflux test were evaluated in paired studies in patients with severe GORD to measure rates of PMA after each meal. Either water labeled with 99m Technetium Phytate for the LGE or a labeled egg sandwich for the solid meal was utilized. Major symptoms were noted and the cough and reflux severity index (CSI & RSI) was obtained in all patients.

Results: A total of 131 patients were enrolled (59M/72F) with age range of 21-83 years (mean: 52 years). Patients were in the overweight range for BMI (mean: 26.8). Major symptoms were bloating, nausea, belching, and dyspepsia (< 20% had heartburn). SGE was abnormal in 92% (mean 766 min) and LGE abnormal in 53% (mean 82 min). PMA was shown in 35% after the SGE and in 71% after the LGE. PMA+ patients were older. A significant correlation was found between SGE and PMA (P < 0.00) but not LGE. The only significant symptom in the PMA group was bloating. RSI was abnormal in 64% and CSI in 46%.

Conclusion: The majority of patients with PMA do not complain of heartburn. Bloating in patients with severe GORD should raise the possibility of gastroparesis and PMA.