Post-operative nausea and vomiting(PONV) is known to occur after bariatric surgery, with over two-thirds of patients affected. However, variability exists in how to objectively measure PONV. The goal of the present study was to use a validated scoring tool, the Rhodes Index of Nausea, Vomiting, and Retching(Rhodes) to measure PONV after bariatric surgery.


Washington University Weight Loss Surgery(WUWLS) surveyed patients from 11/01/2017 to 11/01/2018 at 6 different timepoints: post-operative day(POD)0, POD1, POD2, POD3-4, the first post-operative outpatient visit(~POD7), and the second post-operative visit(~POD40). A Rhodes score was calculated from the sum of 8 validated questions(Table 1) after laparoscopic sleeve gastrectomy(LSG) and laparoscopic Roux-en-Y gastric bypass(LRYGB).


A total of 309 patients completed 695 Rhodes questionnaires were completed. Rhodes questionnaires were completed 297 times by patients after LSG and 398 times by patients after LRYGB. On POD0 and POD1, patients had significantly worse Rhodes scores after LSG compared to LRYGB(Figure 1). Using linear regression assessing procedure, gender, age, and other factors, WUWLS found that LSG(ß=3.72, t-statistic=6.98, p<0.001), female gender(ß=2.33, t-statistic=3.28, p=0.001), and absence of gastroesophageal reflux disease(GERD, ß=1.39, t-statistic=2.46, p=0.01) were associated with higher Rhodes scores POD0 and POD1.


This is the largest study using a validated questionnaire to objectively measure PONV after bariatric surgery. The factors found to be most associated with PONV were LSG, female gender, and absence of GERD. These data may help bariatric surgery programs, including WUWLS, identify patients who may require more intensive treatment of PONV, particularly POD0 and POD1.