Shaun Johnson is a Medical Student at Case Western Reserve University School of Medicine in Cleveland, Ohio. Steven Waisbren is a Surgeon and Assistant Service Chief at the Minneapolis Veterans Affairs Health Care System in Minnesota and an Assistant Professor of Surgery at the University of Minnesota. Correspondence: Steven Waisbren (steven.waisbren@va.gov)
Author disclosures
The authors report no actual or potential conflicts of interest with regard to this article.
Disclaimer
The opinions expressed herein are those of the authors and do not necessarily reflect those of Federal Practitioner, Frontline Medical Communications Inc., the US Government, or any of its agencies. This article may discuss unlabeled or investigational use of certain drugs. Please review the complete prescribing information for specific drugs or drug combinations—including indications, contraindications, warnings, and adverse effects—before administering pharmacologic therapy to patients.
Background: Patients presenting with suspected infections are typically placed on empiric broad-spectrum antibiotics. With mounting evidence supporting the efficacy of using the narrowest spectrum of antimicrobial therapy to cover the suspected pathogen, current guidelines recommend decreasing the breadth of coverage in response to culture results both in relation to microbe identification and antibiotic sensitivity.
Methods: A retrospective chart review of electronic health records at the Minneapolis Veterans Affairs Medical Center (VAMC) in Minnesota was performed for 208 positive blood cultures with antibiotic spectrum analysis from July 1, 2015 to June 30, 2016. The time of reporting for pathogen identification and subsequent pathogen susceptibilities were compared to the time at which any alterations to antibiotic coverage were made. The breadth of antibiotic coverage was recorded using a nonlinear spectrum score. The use of this score allowed for the reliable classification of antibiotic adjustments as either deescalation, escalation, or no change.
Results: The percentage of cases deescalated was higher in response to physician (house staff or attending physician) notification of pathogen susceptibility information when compared with a response to pathogen identification alone (33.2% vs 22.6%). Empiric antibiotics were not altered within 24 hours in response to pathogen identification in 70.7% of cases and were not altered within 24 hours in response to pathogen sensitivity determination in 58.6% of cases. However, when considering the time frame from when empiric antibiotics were started to 24 hours after notification of susceptibility information, 49.5% of cases were deescalated and 41.5% of cases had no net change in the antibiotic spectrum score. The magnitude of deescalations were notably larger than escalations. The mean (SD) time to deescalation of antibiotic coverage was shorter ( P =.049) in response to pathogen identification at 8 (7.4) hours compared with sensitivity information at 10.4 (7) hours, but may not be clinically relevant.
Conclusion: Health care providers at the Minneapolis VAMC appear to be using positive blood culture results in a timely fashion consistent with best practices. Because empirically initiated antibiotics typically are broad in spectrum, the magnitude of deescalations were notably larger than escalations. Adherence to these standards may be a reflection of the infectious disease staff oversight of antibiotic administration. Furthermore, the systems outlined in this quality improvement study may be replicated at other VAMCs across the country by either in-house infectious disease staff or through remote monitoring of the electronic health record by other infectious disease experts at a more centralized VAMC. Widespread adoption throughout the Veterans Health Administration may result in improved antibiotic resistance profiles and better clinical outcomes for our nation’s veterans
The US Department of Veterans Affairs (VA) is the largest health care organization in the US, staffing more than 1,200 facilities and servicing about 9 million veterans.1 Identifying VA practices that promote effective health care delivery has the potential to impact thousands of patients every day. The Surgical service at the Minneapolis VA Medical Center (MVAMC) in Minnesota often questioned colleagues whether many of the ordered tests, including blood cultures for patients with suspected infections, were clinically necessary. Despite recommendations for utilizing culture-driven results in choosing appropriate antimicrobials, it was debated whether these additional tests were simply drawn and ignored resulting only in increased costs and venipuncture discomfort for the patient. Thus, the purpose of this quality improvement study was to determine whether positive blood culture results actually influence clinical management at MVAMC.
Background
Accepted best practice when responding to positive blood culture results entails empiric treatment with broad-spectrum antibiotics that subsequently narrows in breadth of coverage once the pathogen has been identified.2-4 This strategy has been labeled deescalation. Despite the acceptance of these standards, surveys of clinician attitudes towards antibiotics showed that 90% of physicians and residents stated they wanted more education on antimicrobials and 80% desired better schooling on antibiotic choices.5,6 Additionally, in an online survey 18% of 402 inpatient and emergency department providers, including residents, fellows, intensive care unit (ICU) and emergency department attending physicians, hospitalists, physician assistants, and nurse practitioners, described a lack of confidence when deescalating antibiotic therapy and 45% reported that they had received training on antimicrobial prescribing that was not fully adequate.7
These surveys hint at a potential gap in provider education or confidence, which may serve as a barrier to ideal care, further confounding other individualized considerations taken into account when deescalating care. These considerations include patient renal toxicity profiles, the potential for missed pathogens not identified in culture results, unknown sources of infection, and the mindset of many providers to remain on broad therapy if the patient’s condition is improving.8-10 A specific barrier to deescalation within the VA is the variance in antimicrobial stewardship practices between facilities. In a recent widespread survey of VA practices, Chou and colleagues identified that only 29 of 130 (22.3%) responding facilities had a formal policy to establish an antimicrobial stewardship program.11
Overcoming these barriers to deescalation through effective stewardship practices can help to promote improved clinical outcomes. Most studies have demonstrated that outcomes of deescalation strategies have equivalent or improved mortalityand equivalent or even decreased length of ICU stay.12-26 Although a 2014 study by Leone and colleagues reported longer overall ICU stay in deescalation treatment groups with equivalent mortality outcomes, newer data do not support these findings.16,20,22
Furthermore, antibiotics can be expensive. Deescalation, particularly in response to positive blood culture results, has been associated with reduced antibiotic cost due to both a decrease in overall antibiotic usage and the utilization of less expensive choices.22,24,26,27 The findings of these individual studies were corroborated in 2013 by a meta-analysis, including 89 additional studies.28 Besides the direct costs of the drugs, the development of regional antibiotic resistance has been labeled as one of the most pressing concerns in public health, and major initiatives have been undertaken to stem its spread.29,30 The majority of clinicians believe that deescalation of antibiotics would reduce antibiotic resistance. Thus, deescalation is widely cited as one of the primary goals in the management of resistance development.5,24,26,28,31,32
Due to the proposed benefits and challenges of implementation, MVAMC instituted a program where the electronic health records (EHR) for all patients with positive blood culture results were reviewed by the on-call infectious disease attending physician to advise the primary care team on antibiotic administration. The MVAMC system for notification of positive blood culture results has 2 components. The first is phone notification to the on-call resident when the positive result of the pathogen identification is noted by the microbiology laboratory staff. Notably, this protocol of phone notification is only performed when identifying the pathogen and not for the subsequent sensitivity profile. The second component occurs each morning when the on-call infectious disease attending physician reviews all positive blood culture results and the current therapy. If the infectious disease attending physician feels some alterations in management are warranted, the physician calls the primary service. Additionally, the primary service may always request a formal consult with the infectious disease team. This quality improvement study was initiated to examine the success of this deescalation/stewardship program to determine whether positive blood culture results influenced clinical management.
Methods
From July 1, 2015 to June 30, 2016, 212 positive blood cultures at the MVAMC were analyzed. Four cases that did not have an antibiotic spectrum score were excluded, leaving 208 cases reviewed. Duplicate blood cultures were excluded from analysis. The microbiology laboratory used the BD Bactec automated blood culture system using the Plus aerobic and Lytic anaerobic media (Becton, Dickinson and Company).
