Evaluation of the Rhodes Index of Nausea and Vomiting for ambulatory surgery patients

Background. The Index of Nausea and Vomiting (INV), developed by Rhodes and others in 1984, measures three dimensions of upper gastrointestinal distress: nausea, vomiting and retching (NVR). While the revised version has been tested with a variety of high‐risk populations, there are no data suggesting that it can be used to assess upper gastrointestinal distress among the growing numbers of ambulatory or day surgery patients. Aim. The aim of this study was to evaluate a modified version of the INV for use with ambulatory surgery patients. Methods. A secondary analysis was conducted using data obtained from a descriptive study designed to identify risk factors for postdischarge nausea and vomiting (PDNV) among adult ambulatory surgery patients. Patients who reported PDNV (n = 190) participated via phone interview 24 hours after discharge by completing a modified Rhodes INV. Findings. Reliability analysis (α = 0·897) indicated that the modified Rhodes INV measured upper gastrointestinal distress as a single concept in the postdischarge ambulatory surgical sample. One item of the 8‐item scale was dropped. Principal component analysis extracted one factor that accounted for 67% of the variance with all items loading. Conclusions. Upper gastrointestinal distress following ambulatory surgery discharge comprises a different symptom mix than during other high‐risk events such as pregnancy or chemotherapy. Further research on the differences in assessing NVR among different populations is indicated.