Predictors of dehydration requiring outpatient intervention following bariatric surgery

Background: Dehydration is a common cause of emergency department visits and readmissions following bariatric surgery. Despite the increasing use of outpatient rehydration therapy (ORT) to manage this complication, predictors of ORT utilization remain poorly understood. Objectives: To identify independent predictors of ORT utilization following bariatric surgery and examine its relationship with same-day discharge (SDS) protocols. Setting: Analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database across accredited bariatric surgical centers. Methods: We analyzed Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data from 2020–2023 for adult patients who underwent primary laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB). Multivariable logistic regression identified independent predictors of ORT utilization. Results: Of 692,525 patients, 26,215 (3.8%) required ORT. These patients were younger (41.5 ± 11.3 versus 43.2 ± 11.8 years, P < .001), had higher body mass index (45.3 ± 7.4 versus 45.1 ± 7.7 kg/m², P < .001), and were more likely to be female (90.0% versus 81.8%, P < .001). ORT rates were higher among RYGB versus sleeve gastrectomy patients (4.3% versus 3.6%, P < .001). SDS patients comprised 7.5% of the cohort but 12.6% of those requiring ORT. Independent predictors of ORT included younger age (odds ratio [OR]: .86 per 10 years), female sex (OR: 1.94), SDS (OR: 2.04), Black race (OR: 1.25), and RYGB (OR: 1.19) (all P < .001). Conclusions: Identifying predictors of ORT use supports effective implementation of SDS protocols through strategic resource allocation. ORT represents a cost-effective approach that enables the benefits of accelerated discharge pathways while preventing costly readmissions. These findings can help bariatric programs optimize outpatient hydration services for high-risk patients, enhancing the overall efficiency and value of care delivery.