Antimicrobial Stewardship in the Emergency Department: It's Growing…Who Are You Going to Call?

Dr Christi Jen from the Banner Boswell Medical Center in Sun City, Arizona, delivered a presentation on antimicrobial stewardship directed toward pharmacists and physicians to help identify opportunities for culture surveillance in an emergency department (ED) setting.

Dr Jen noted the importance of infection control in the ED, which is the usual place of healthcare for about 3% of patients. Of all ED visits, about 4.5% are due to infectious conditions such as urinary tract infections and cellulitis, which provide an opportunity to improve care.

Dr Jen described some of the steps involved in determining the appropriateness of antibiotics for patients in the ED. These steps include receipt of test results carried out on blood and cerebrospinal fluid and formulation of an immediate action plan for positive gram stain results that indicate the presence of bacteria. After dealing with critical matters, a review of culture susceptibility, drug allergies, concomitant medications, kidney function, and liver function may help the pharmacist make a determination of the most appropriate therapy. Other considerations such as pregnancy, age, prior hospitalizations, prior surgeries, and the presence of implanted medical devices are also taken into account. Assessment of drug interactions, the susceptibility of pathogens to therapy, and the need for dose adjustments based on organ function is also made. Finally, patient counseling, including a discussion with the patient about adherence, completes this process.

The importance of knowing the individual care center’s susceptibility pattern, or antibiogram, as well as the importance of judicious antimicrobial use, was also described. For instance, in treating an enteric gram-negative pathogen, one might empirically use a first-generation injectable cephalosporin such as cefazolin. With results that indicate poor bacterial susceptibility to cefazolin, a pharmacist might recommend a third- or fourth-generation antibiotic such as ceftriaxone or cefepime with an improved spectrum of gram-negative activity over first-generation agents. Suppressing use of extended-spectrum agents based on a patient’s individual susceptibility patterns improves antimicrobial use and helps prevent the development of resistance.

Another part of finding the right regimen for the patient includes adjusting antibiotic dosing depending on liver function or kidney function. Using techniques such as the Child-Pugh score to measure liver function and the Cockroft-Gault equation to assess kidney function allows for a more appropriate dosing recommendation. Knowing these parameters becomes important when antibiotics cannot be used safely below a certain kidney- or liver-function threshold, especially in specific patient populations such as the elderly. Even for patients with no kidney or liver dysfunction, knowing and enforcing maximum doses of medications protects patient health.

Use of other medication may affect the elimination of a drug from the body. In the context of antimicrobial use, assessing the use of concomitant medications, with an emphasis on amiodarine, warfarin, oral contraceptives, and methotrexate, may also prevent overexposure or underexposure to an antimicrobial regimen. Dr Jen often advises patients of drug interactions and follows up with a physician or specialist to discuss drug interaction management.

According to Dr Jen, a pharmacist-managed culture review process showed a significant reduction in the incidence of unplanned patient readmissions due to treatment failure, medication nonadherence, or drug allergy versus a physician-managed culture review process. The institution of this pharmacist-managed program also reduced the overall physician workload by 50 hours every week. An institution with a similar program in Rochester, New York, also experienced a significant benefit in terms of quantifiable outcomes such as time to culture review and time to primary care provider notification.

In closing, Dr Jen reviewed case studies that demonstrate some of the day-to-day decisions made in the clinical practice setting. She also highlighted some of the benefits of pharmacist-administered programs including culture surveillance, reduced readmission rates, and reduced workload of other providers in the ED setting. Dr Jen ended the discussion with a positive outlook on the future of antimicrobial stewardship with pharmacist-directed programs and an emphasis on collaborative practice and more comprehensive treatment programs.