The Impact of Dehydration on Short-Term Postoperative Complications in Total Knee Arthroplasty

Background: As healthcare economics shifts towards outcomes based bundled payment models, providers must understand the evolving dynamics of medical optimization and fluid resuscitation prior to elective surgery. Dehydration is an overlooked modifiable risk factor that should be optimized prior to elective total knee arthroplasty (TKA) to reduce postoperative complications and inpatient costs. Methods: All primary TKA from 2005-2019 were queried from the National Surgical Quality Improvement Project (NSQIP) database, and patients were compared based on dehydration status: BUN/Cr < 20 (non-dehydrated), 20 ≤ BUN/C ≤ 25 (moderately-dehydrated), 25 65 years and normalized gender-adjusted creatinine (Cr) values was also performed. Results: The analysis included 344,744 patients who underwent TKA. Adjusted multivariate logistic regression analysis showed that the severely dehydrated cohort had a greater risk and rate of overall complications, postoperative deep vein thrombosis (DVT), urinary tract infections (UTI), progressive renal insufficiency, postoperative anemia requiring transfusion, nonhome discharge, and increased length of stay (LOS) (all p<0.01). Among the elderly, dehydrated patients had a greater risk of postoperative transfusion, cardiac complications, and nonhome discharge (all p<0.01). Conclusions: BUN/Cr>20 is an important preoperative diagnostic tool to identify at-risk dehydrated patients. Providers should optimize dehydration to prevent complications, decrease costs, and improve discharge planning. Level of evidence Level III; Retrospective Case-Control Design; Prognosis Study