Association of laboratory test result availability and rehospitalizations in an outpatient parenteral antimicrobial therapy programme.

Objectives: Laboratory tests are usually requested for monitoring during outpatient parenteral antimicrobial therapy (OPAT), but these recommendations are not always followed. The purpose of this study was to determine whether rehospitalization during the OPAT course is associated with the availability of these test results to the treating physician.

Methods: Electronic health records (EHRs) from all patients in the Cleveland Clinic OPAT registry with start dates from 1 January to 28 February 2011 were reviewed in a retrospective cohort study. Comprehensive data on patient and OPAT characteristics were obtained for the first OPAT course per patient. Availability of laboratory test results was defined as documentation of results of at least one recommended test in the health system's EHR. Proportions of patients rehospitalized were compared for OPAT courses with test results available and non-available. Adjustments were made for patient age, hospital length of stay, anticipated OPAT duration, OPAT site and Charlson comorbidity index score.

Results: Four hundred patients received OPAT during the study period; 60% at home, 36% in skilled nursing facilities or long-term acute care facilities and 4% in other settings. Recommended monitoring laboratory test results were available to infectious disease physicians in 291 (73%) OPAT episodes. There were 82 patient readmissions (21%) while on OPAT. In a multivariable logistic regression model, non-availability of recommended test results was independently associated with readmissions while on OPAT (adjusted OR 2.53; 95% CI 1.36-4.73).

Conclusions: Non-availability of recommended test results to treating physicians for patients on OPAT is associated with increased readmissions during OPAT.