This study, over a 6-year period and in a real-life setting, analyzed the impact of antimicrobial use on microbial outcomes, along with a comprehensive ASP focusing on aCDSS, feedback & monitoring, weekly review of antimicrobials and multidisciplinary team discussion of antimicrobial regimens and education on antimicrobial use. Measuring the impact of an ASP is crucial to maintain administrative support and we provided real-world experience from established ASPs in critical care settings. The aCDSS consists of several components including intervention in microbiological specimen sampling practice, hierarchical stewardship, education resources, and antimicrobial prescription recommendations. The design of this practice-based study was not to specifically measure the impact of any individual initiative but rather an integrated program in critical care.
We used data from academic hospital ICUs covering 6 years. As one of the wards with highest antimicrobial consumption, ICU is a gathering place for immunocompromised patients, and the nosocomial infection prevalence is much higher due to wide-spread use of broad-spectrum antimicrobials, glucocorticoids, immunosuppressive agents, and various invasive procedures than that of the ordinary wards. An international PPS indicates that 51% of the 1,265 ICUs in 75 countries around the world have infections identified and 71% are prescribed antimicrobials. On one hand, a prompt institution of effective antimicrobial regimens for proper coverage of causative pathogens is vital in critically ill patients and involves physicians with infectious disease expertise considering the complexity of decision-making process; On the other hand, an indiscriminate use of broad-spectrum antimicrobials is closely contributed to mortality[36, 37], with higher AMR burden. In this regard, timely and accurate retention of microbiological specimens to obtain appropriate cultures before antimicrobial administration is the basis for targeted therapy, obtaining more reliable local antimicrobial susceptibility patterns to increase the likelihood of prescribing appropriate initial antimicrobials, especially for patients with a higher risk of death in patients in the ICU. Our study has demonstrated that the introduction of an antimicrobial decision support tool into the ICU, ensuring the pre-conditions of microbiological specimens sampling before therapeutic antimicrobials use, was associated with measurable improvements in both initial antimicrobial use and overall use. Given that it has long been recognized that the inability to easily get access on data on local antimicrobial use patterns can be a gap[39–41], standardized metrics to individual facilities across a healthcare system has been a major advance. CDSS linked to EMRS and other clinical systems to this computerized platform has been proved to have the potential to facilitate the dissemination of information to intensivists for optimal use in therapeutic decision-making[42–46]. We consider all antimicrobial prescribing important and have shown that it is feasible to make full use of web-based application to help work with intensivists to improve antimicrobial prescribing practice by considering all patients’ accompanying microbiology diagnostic testing issues helping the interpretation of some of our results and encouraging evidence-based decisions regarding choice of therapy. Our study achieved significantly reduced use of carbapenems, glycopeptides, third/fourth-generation cephalosporins and anti-fungi agents in all.
Our study has a number of limitations. Firstly, it is an observational study in a single center without randomization and thus is subject to known biases. Secondly, many confounding factors interfere with the judgment of AMS performance. For example, rapid diagnostic test plays a collaborative role for ASPs. At last, this study occurred in academic ICUs, most of the patients admitted to our ICUs were not “first-hand” patients who had been prescribed antimicrobials in community medical institutions or outpatient clinics before, thus, the microbiological data obtained through aCDSS was already partially biased, Furthermore, academic ICUs differ from community-based ICUs or long-term nursing care institutions in terms of staffing models and admitting more complex patients receiving broader spectrum antimicrobials. This study only represents the efforts of an established ASP with appropriate resourcing for wed-based interventions and may not be generalizable to other centers. In summary, while we were able to show temporal improvements in antimicrobial utilization structure concerning our interventions, larger, appropriately conducted randomized controlled trials or at least a controlled quasi-experimental design with longitudinal time series analysis are needed to further evaluate the effects of ASP including CDSS in critical care settings[48, 49].