title: Evaluation of medication safety in the discharge medication of 509 surgical inpatients using electronic prescription support software and an extended operational interaction classification.
abstract: OBJECTIVE
  Our aim was to study drug interactions and dose adjustments in patients with renal impairment in the discharge medication of surgical inpatients and to evaluate the strengths and limitations of clinical decision support software (CDSS) for this task.
  
  
  METHODS
  This was a cross-sectional study involving 509 surgical patients of a primary care hospital. We developed a customized interface for the CDSS MediQ, which we used for automated retrospective identification of drug interactions in the patients' discharge medication. The clinical relevance of the interactions was evaluated based on the Zurich Interaction System (ZHIAS) that incorporates the operational classification of drug interactions (ORCA). Prescriptions were further analyzed for recommended dose adjustments in patients with a glomerular filtration rate <60 ml/min.
  
  
  RESULTS
  For the total of 2,729 prescriptions written for the 509 patients enrolled in the study, MediQ generated 2,558 interaction alerts and 1,849 comments. Among these were ten "high danger" and 551 "average danger" alerts that we reclassified according to ORCA criteria. This reclassification resulted in ten contraindicated combinations, 77 provisionally contraindicated combinations, and 310 with a conditional and 164 with a minimal risk of adverse outcomes. The ZHIAS classification also provides categorical information on expected adverse outcomes and management recommendations, which are presented in detail. We identified 56 prescriptions without a recommended dose adjustment for impaired renal function.
  
  
  CONCLUSIONS
  CDSS identified a large number of drug interactions in surgical discharge medication, but according to ZHIAS criteria only a minor fraction of these appeared to involve a substantial risk to the patient. CDSS should therefore aim at reducing over-alerting and improve usability in order to become more efficacious in terms of the prevention of adverse drug events in clinical practice.
authors.affiliation: Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Frölich
authors.forename: Olesya
authors.initials: O
authors.lastname: Zorina
authors.forename: Andrea O
authors.initials: AO
authors.lastname: Fontana
authors.forename: Gerd A
authors.initials: GA
authors.lastname: Kullak-Ublick
authors.forename: Andreas
authors.initials: A
authors.lastname: Vollenweider
authors.forename: Stefan
authors.initials: S
authors.lastname: Russmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D020000:Decision Support Systems, Clinical; D004347:Drug Interactions; D055695:Electronic Prescribing; D005260:Female; D005919:Glomerular Filtration Rate; D006769:Hospitals, General; D006801:Humans; D007297:Inpatients; D007674:Kidney Diseases / Q000188:drug therapy / Q000503:physiopathology; D008297:Male; D059065:Medication Reconciliation; D008875:Middle Aged; D010351:Patient Discharge / Q000706:statistics & numerical data*; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*; D013503:Surgery Department, Hospital / Q000706:statistics & numerical data*; D013557:Switzerland; D055815:Young Adult
chemical_list: D004364:Pharmaceutical Preparations