Appendix Figure B. Flow Diagram of Electronic Algorithm for Candidate.

Appendix Figure B is a flow diagram demonstrating the electronic algorithm’s protocol for processing information from multiple electronic databases. Boxes shaded in light grey indicate electronic databases accessed by the algorithm. White boxes and arrows describe sequential steps processed by the algorithm. Dark grey boxes indicate stopping points in the algorithm (e.g., when a potential CAUTI is “screened out” and discarded or is deemed to be a candidate CAUTI).As in traditional surveillance, the eligible patient pool of catheterized patients is identified via the electronic nursing care record. The MRNs and indwelling urinary catheter documentation dates for the eligible patient pool then form the basis of an automated query of the hospital’s Clinical Data Repository (CDR), a real-time data warehouse of clinical and microbiological data collected by multiple hospital systems. Based on the 2012 NHSN surveillance definition for CAUTI, we defined a patient’s duration of CAUTI development eligibility from the first urinary catheter presence documentation date during an admission through 48 hours beyond the last documentation date. Catheterization time windows separated by more than 2 calendar days were treated as unique catheterization events. If more than one urine culture existed during the time frame for each report generated by the electronic algorithm, the query returned the first positive culture that met the NHSN microbiological and laboratory data requirements.

The electronic algorithm determined hospital unit of assignment by selecting the inpatient location of the patient 48 hours prior to the urine culture collection date. If a patient was classified as a non-inpatient at this time, the candidate CAUTI was assigned to the patient’s first inpatient location per NHSN guidelines, and the case was flagged for an additional review for possible UTI presence on admission. In addition, the electronic algorithm also generated a note of the number and dates of positive cultures occurring between 14 days prior to admission and 2 days after admission to aid in chart review determination of whether or not a UTI was preexisting. Supplementary elements of the algorithm-generated report included patient demographics, the start and end dates of a patient’s indwelling urinary catheter placement time period, patient location at the time of urine specimen collection, urine culture and urinalysis results, and an indication of whether or not a blood culture was performed within 48 hours of the positive urine culture.