Abstract
BACKGROUND
High-dose antibiotic cement spacers are commonly used to treat prosthetic joint infections following knee arthroplasties. Several clinical studies have shown a high success rate with antibiotic cement spacers, however there is little data on the systemic complications of high-dose antibiotic spacers, particularly acute kidney injury (AKI). This study aims to determine the incidence of AKI and identify risk factors predisposing patients undergoing staged revision arthroplasty with antibiotic cement spacers.
METHODS
A single-institution, retrospective review was used to collect and analyze clinical and demographic data for patients who underwent staged revision total knee arthroplasty with placement of an antibiotic-impregnated cement spacer from 2006 to 2016. A search was made through specific procedure (DRG) and diagnostic (CD) codes. Baseline descriptive data were collected for all patients including age, sex, medical comorbidities, type and quantity of antibiotics used in the cement spacer, pre- and postoperative hemoglobin (Hg), BMI, smoking status, peak creatinine levels, and random vancomycin levels. Acute kidney injury was defined as a more than 50% rise in serum creatinine from a preoperative baseline within 90 days postoperatively.
RESULTS
A total of 54 staged revision TKA surgeries performed by 5 different surgeons between 2006 and 2016. The total incidence of AKI was 31% (n=17). There was a significant positive association between change in creatinine level and use of oral/intravenous antibiotics (p=0.03, Spearman's rho=0.33) and a significant positive association between AKI and the use of tobramycin cement (p=0.01, Spearman's rho=0.38). Factors that were not significantly associated with AKI include presence of preexisting hypertension (p = 0.26), hyperlipidemia (p = 0.83), coronary artery disease (p = 0.86), chronic kidney disease (p=0.56), and smoking status (p=.35). There was a trend towards increased risk of AKI in patients with diabetes mellitus (p= 0.12), however this was not significant.
CONCLUSION
In single staged revision knee arthroplasty there is a significant association between acute kidney injury and type of oral/intravenous antibiotic used in the treatment. Both the use of intravenous vancomycin and tobramycin cement are independently associated with higher rates of AKI. Preexisting medical comorbidities are not independent risk factors for development of AKI. Serum creatinine and measurement of serum aminoglycoside and vancomycin levels should be performed after placement of an aminoglycoside-containing antibiotic cement spacer in a staged revision arthroplasty.
