Impact of an Innovative Smartphone “App” on Intensive Care Unit (ICU) Antimicrobial Utilization Across a Large Metropolitan Health Region in Canada: an Interrupted Time Series Analysis

Background: SpectrumMD is a customizable stewardship smartphone app that offers algorithmic decision support based on clinical guidelines and local microbiology data. The app was introduced to all ICU prescribers across a large metropolitan health region followed by an interrupted time series analysis (ITSA) to evaluate the impact on ICU antimicrobial utilization (AMU).

Methods: SpectrumMD was launched 1/11/2013 to ICU prescribers with monthly educational sessions. Penetration of the app was tracked with Flurry Analytics™, a post-intervention survey, and via session attendance. An uncontrolled before-after intervention ITSA (SPSS v19.0) was performed to compare AMU in the 12 months pre- and post-intervention (allowing a 3 month wash-in period) using daily defined doses/100 patient days. Patient demographics, central line associated bloodstream infection (CLABSI) and influenza rates were analyzed for both time periods. Student’s t test was used for continuous variables and two-tailed χ² or Fishers exact as appropriate for categorical variables.

Results: Patient characteristics were similar between the pre- (n=2867) and post-intervention (n=2717) groups, including age (x 56.9 vs. 56.3 years), admission APACHE (19.7 vs. 19.6), and immunosuppression (15% vs. 16%), as were rates of CLABSI and influenza. Post wash-in there were 634 active SpectrumMD users within the health region, which increased to 1145 during the post-intervention period, and 76% (54/71; response rate 34%) of survey respondents reported using the app during their ICU rotation. There was no statistically significant change in overall AMU between the time periods. Agent-specific analysis revealed a trend toward decreased anti-pseudomonal utilization (slope change parameter -0.983; p=0.07). Of 64 respondents, 70% agreed this app changed their antimicrobial prescribing practices while 89% would recommend it to colleagues.

Conclusion: SpectrumMD was a widely accepted intervention that yielded positive user feedback. Though there was no significant reduction in overall AMU, a trend toward decreased anti-pseudomonal agent use may represent more appropriate antimicrobial prescribing. Further longitudinal analysis is required to assess the impact of this promising app.