140. One-Time Dose of Gentamicin (GENT) for Surgical Prophylaxis (SP) Does Not Increase Risk for Postoperative (POSTOP) Acute Kidney Injury (AKI)
Session: Poster Abstract Session: Antimicrobial Stewardship: Adverse Drug Events
Thursday, October 8, 2015
Room: Poster Hall
  • Gent Surg ppx AKI ID Week Poster.png (162.7 kB)
  • Background: Antibiotic selection for SP is based on the drugs’ ability to achieve adequate tissue concentrations, cover organisms at the operative site, patients’ allergy profile and local resistance patterns. Radical cystectomy (RC) patients at our institution received cefoxitin or a fluoroquinolone (FQ). Due to increasing FQ resistance and POSTOP infections in RC patients, GENT (4mg/kg) was instituted for SP in May 2013 to offer broader spectrum coverage against FQ resistant Enterobacteriaceae. Since nephrotoxicity is a concern with aminoglycosides, we evaluated the safety of GENT for SP by comparing incidence of POSTOP AKI in RC patients who received GENT vs historical controls. 

    Methods: Adult patients who underwent RC between 3/1/2012-5/22/2013 and 5/23/2013-5/30/2014 were included. Patients with end stage renal disease were excluded. Renal function was evaluated for 5 days POSTOP. AKI was defined per RIFLE criteria and risk factors were assessed via regression analysis. 

    Results: A random sample of 109 patients were reviewed (No GENT: 49; GENT: 60). Demographics and operating room (OR) time were similar between the 2 groups. All except 6 patients received a one-time dose of GENT (2 doses: 2, 3 doses: 4). Mean GENT dose was 4.3 ± 1.1mg/kg.  Incidence of POSTOP AKI did not change with the addition of GENT (65% vs 57%, p = 0.36). Degree of AKI was distributed as follows: risk (24% vs 28%, p = 0.65), injury (35% vs 41%, p = 0.19), failure (6% vs 5%, p = 0.80). Risk factors and their association with POSTOP AKI are shown in table 1. DM, BMI ≥ 30, age ≥ 65 and OR time met a priori p < 0.2 for inclusion in multivariate (MV) analysis. Age ≥ 65 was the only significant risk factor in MV analysis [OR 3.3 (95% CI 1.3-8.8), p = 0.02].

    Table 1. Univariate Analysis of Risk Factors Associated with POSTOP AKI


    OR (95% CI)



    3.5 (1.2-10.3)


    Chronic Kidney Disease

    2.4 (0.5-12.3)


    BMI ≥ 30

    1.8 (0.8-4.1)


    Other Nephrotoxic Medications

    1.5 (0.7-3.2)


    POSTOP Hypotension

    1.5 (0.6-3.2)


    Age ≥ 65

    2.4 (1.1-5.6)



    0.7 (0.3-1.5)


    Vancomycin (VAN) + GENT

    1.7 (0.5-6.0)


    OR Time

    1.0 (0.99-1.01)


    Conclusion: POSTOP AKI is multifactorial and elderly patients are at increased risk. GENT or VAN + GENT are not associated with increased risk of POSTOP AKI and are safe options for SP.

    Zhe Han, PharmD1, Natasha Pettit, PharmD1, Amanda Dugal, PharmD1, Joseph Pariser, MD2, Blake Anderson, MD2, Shane Pearce, MD2, Gary Steinberg, MD2, Norm Smith, MD2 and Jennifer Pisano, MD3, (1)Pharmacy Services, The University of Chicago Medicine, Chicago, IL, (2)Section of Urology, Department of Surgery, The University of Chicago Medicine, Chicago, IL, (3)Infectious Diseases and Global Health, The University of Chicago Medicine, Chicago, IL


    Z. Han, None

    N. Pettit, None

    A. Dugal, None

    J. Pariser, None

    B. Anderson, None

    S. Pearce, None

    G. Steinberg, None

    N. Smith, None

    J. Pisano, None

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