Hypoalbuminemia Increased the Length of Stay in the Treatment of Postoperative Acute Surgical Site Infection in Spinal Surgery.

STUDY DESIGN Multicenter retrospective study. OBJECTIVE To identify specific risk factors for increased length of stay (LOS) in the management of acute surgical site infection (SSI) following spinal surgery. SUMMARY OF BACKGROUND DATA Postoperative SSI is a serious complication of spinal surgery and is known to be associated with increased LOS and additional cost. Although many risk factors contribute to the development of SSI following spinal surgery, little is known about risk factors associated with the treatment of SSI that contribute to increased LOS. METHODS Patients at two institutions experiencing deep SSI following spinal surgery between January 2009 and December 2016 were identified. The patients were divided into two groups depending upon the median LOS attributable to SSI. The effects of patient characteristics, comorbidities, disease history, and invasiveness of the elective surgery on the risk of increased LOS were determined using univariate analyses and multivariate logistic regression. RESULTS Of the 1656 spinal surgery cases, 40 (2.4%) experienced deep SSI. The median LOS was 67 days. Multivariate logistic regression analysis revealed that hypoalbuminemia during hospitalization was associated with increased LOS (odds ratio 0.042, confidence interval 0.005-0.342; P = 0.003). We determined the appropriate diagnostic cutoff of hypoalbuminemia during hospitalization using receiver operating characteristic curves. A serum albumin level <3.1 g/dL (sensitivity, 86.4%; specificity, 75.0%; area under the curve, 0.84) was indicative of a longer hospital stay. CONCLUSIONS Low serum albumin level during hospitalization was an independent risk factor for increased LOS in the treatment of SSI following spinal surgery. When the serum albumin level is <3.1 g/dL in patients with SSI, we should consider interventions aimed at correcting this hypoalbuminemia. LEVEL OF EVIDENCE 4.