Impact of a newly established expert clinical pharmacological advice program based on TDM results in tailoring antimicrobial therapies hospital-wide in a tertiary university hospital: findings after the first-year of implementation

Therapeutic drug monitoring (TDM) may be helpful in tailoring treatment with antimicrobials, and expert interpretation of the results may make it more clinically useful. The study aim was to assess retrospectively the first-year impact (July 2021-June 2022) of a newly established expert clinical pharmacological advice program (ECPA) based on TDM results in tailoring therapy with 18 antimicrobials hospital-wide in a tertiary university hospital. All patients having ≥1 ECPA were grouped in five cohorts [hematology, intensive care unit (ICU), pediatrics, medical- and surgical- wards]. Four indicators of performance were identified [total ECPAs; total ECPA recommending dosing adjustments/total ECPAs both at first and at subsequent assessments; turnaround time (TAT) of ECPAs, defined as optimal (<12h), quasi-optimal (12–24h), acceptable (24–48h), suboptimal (>48h)]. A total of 8484 ECPAs were provided for tailoring treatment in 2961 patients, mostly admitted in the ICU (33.8%) and in the medical wards (29.4%). The proportions of ECPAs recommending dosing adjustments were >40% at first assessment (40.9% in hematology; 62.8% in ICU; 53.9% in pediatrics; 59.1% in medical wards; 59.7% in surgical wards), and decreased consistently at subsequent TDM assessments (20.7% in hematology; 40.6% in ICU; 37.4% in pediatrics; 32.9% in medical wards; 29.2% in surgical wards). The overall median TAT of the ECPAs was optimal (8.11h). The TDM-guided ECPA program was successful in tailoring treatment with a wide panel of antimicrobials hospital-wide. Expert interpretation by MD clinical pharmacologists, short TATs and strict interaction with ID consultants and clinicians were crucial in attaining this.