Evaluating the effect of NPO status on mucosal coating during double contrast barium esophagrams

Current guidelines for double contrast barium esophagography studies (BAS) suggest that patients should be nil per os (NPO) prior to completing BAS for optimal esophageal coating, although the time required varies between practices and institutions. It is believed that consumption of food or water disrupts the ability for thick barium contrast to properly coat the esophageal mucosa. Exams that are rescheduled for this reason can lead to delays in care, without substantial evidence that NPO status truly affects esophageal mucosal coating for these exams with current barium mixtures.

The study aims to identify the necessity, or lack thereof, of standard NPO protocol in patients undergoing BAS, in effort to prevent unnecessary procedural delay.

This study is an IRB-approved HIPAA-compliant study of 370 consecutive adult patients (115 male/255 female, mean age 55) who underwent BAS at our institution from January to June of 2022. Patients were divided into two groups: < 4 h NPO (n = 334), and ≥ 4 h NPO (n = 36). Four abdominal radiologists blinded to NPO interval independently reviewed a random sample of approximately 92 patients (91-94) and graded esophageal coating on a 4-point-scale with 1 being insufficient coating and 4 being optimal coating.

No significant statistical difference in mean esophageal coating score was found between the ≥ 4 h NPO cohort (3.04 ± SD 0.78) and the < 4 h NPO cohort (2.97 ± SD 0.70; P = 0.54). Subset analysis of patients who were NPO for < 2 h (n = 9) also showed no significant difference in mean esophageal coating score (3.11 ± SD 0.6; P = 0.92), compared to the standard ≥ 4 NPO status.

Non-adherence to standard NPO protocol prior to BAS studies did not result in a significant difference in esophageal coating when compared to traditional preprocedural fasting of 4 or more hours.