Risk factors for deep surgical site infections after spinal fusion

Abstract

Surgical site infections (SSI) are undesired and troublesome complications after spinal surgery. The reported infection rates range from 0.7 to 11.9%, depending on the diagnosis and the complexity of the procedure. Besides operative factors, patient characteristics could also account for increased infection rates. Because the medical, economic and social costs of SSI are enormous, any significant reduction in risks will pay dividends. The purpose of this study is to compare patients who developed deep SSI following lumbar or thoracolumbar spinal fusion with a randomly selected group of patients who did not develop this complication in order to identify changeable risk factors. With a case-control analysis nested in a historical cohort of patients who had had a spinal fusion between January 1999 and December 2008, we identified 36 cases with deep SSI (CDC criteria). Information regarding patient-level and surgical-level risk factors was derived from standardized but routinely recorded data and compared with those acquired in a random selection of 135 uninfected patients. Univariate analyses and a multivariate logistic regression were performed. The overall rate of infection in 1,615 procedures (1,568 patients) was 2.2%. A positive history of spinal surgery was associated with an almost four times higher infection rate (OR = 3.7, 95% BI = 1.6-8.6). The risk of SSI increased with the number of levels fused, patients with diabetes had an almost six times higher risk and smokers had more than a two times higher risk for deep SSI. The most common organism cultured was Staphylococcus aureus. All infected patients underwent at least one reoperation, including an open débridement and received appropriate antibiotics to treat the organism. Patients who had had a previous spinal surgery are a high-risk group for infection compared with those that never had surgery. Total costs associated with preventive measures are substantial and should be compensated by health care insurance companies by means of separate clinical pathways. High-risk patients should be informed about the increased risk of complications.

Does Minimally Invasive Surgery Have a Lower Risk of Surgical Site Infections Compared With Open Spinal Surgery?

“…This finding was similar to that found in the literature where S aureus was noted to occur in more than 50% of postoperative spine infection [2,4,15]. In our series, all patients were managed conservatively with intravenous antibiotics and only 13 patients required additional surgical intervention.…”

Body mass index and risk of surgical site infection following spine surgery: a meta-analysis

“…Of the 34 articles that underwent full-text review, 12 [22][23][24][25][26][27][28][29][30][31][32][33] met eligibility criteria for inclusion in the meta-analysis and 22 were excluded. The most common reasons for exclusion of the 22 studies were: criteria for the diagnosis of SSI not reported and/or CDC/NNIS criteria not applied [34][35][36][37][38][39][40][41][42][43][44][45][46][47], non-scalar definitions of obesity used [47][48][49], risk estimates of the association between obesity/BMI and SSI not reported or raw data not provided to calculate risks [44,47,[50][51][52][53], and analyses restricted to deep wound infections [54,55].…”

Lumbar instrumented posterolateral fusion in spondylolisthetic and failed back patients: a long-term follow-up study spanning 11–13 years

“…In spite of the few primary complications seen in this study, as fusion operations do carry risks, the patients' responses to conservative treatment should be observed for a sufficient time before evaluating the need for operation. The risk of complications is higher for reoperations [25]. Degenerative changes may continue unabated, affecting adjacent segment alterations and leading to ASD in the long run.…”