Dehydration risk factors and impact after bariatric surgery: an analysis using a national database

Dehydration is a common complication after bariatric surgery and often quoted as the reason for emergency department (ED) visits and readmission.

We sought to investigate risk factors for dehydration after bariatric surgery and evaluate its impact on ED visits and readmission.

The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database.

We used the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database to identify patients who underwent laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass (LRYGB) from 2016 through 2017. The primary outcome was need for outpatient treatment of dehydration within 30 days postsurgery. Secondary outcomes were association between need for outpatient dehydration therapy and 30-day readmission or ED evaluation not resulting in admission.

Of 256,817 patients, 73% underwent laparoscopic sleeve gastrectomy and 27% LRYGB. Of 9592 patients who required dehydration treatment, they were more often younger than age 40, female, black, had a ≥3-day length of stay during their index admission, and experienced a postoperative complication. More patients receiving LRYGB than laparoscopic sleeve gastrectomy required treatment for dehydration. On multivariable analysis, independent-risk factors for postoperative dehydration treatment included LRYGB, length of stay ≥3 days, gastroesophageal reflux disease, hypertension, previous deep vein thrombosis, chronic steroid/immunosuppression, and a postoperative complication. Patients who developed dehydration requiring treatment compared with those that did not had adjusted odds ratio of 3.7 (95% confidence interval: 3.44-3.96; P < .001) and 22 (95% confidence interval: 21.05-23.06; P < .001) of readmission and ED visit.

Dehydration is a strong risk factor for postoperative ED visits and readmission. Closer surveillance and proactive measures for those at higher risk may prevent the development of postoperative dehydration.