title: Omitted doses as an unintended consequence of a hospital restricted antibacterial system: a retrospective observational study.
abstract: OBJECTIVE
  The objective of this study was to determine the frequency of omitted doses of antibacterial agents and explore a number of risk factors, including the effect of a restricted antibacterial system.
  
  
  METHODS
  Antibacterial data were extracted from a hospital electronic prescribing and medication administration system for the period 1 January to 30 April 2014. Percentage dose omission rates were calculated. Omission rates for the first dose of antibacterial courses were analysed using logistic regression to identify any correlation between first dose omission rates and potential risk factors, including the antibacterials' restriction status and whether or not they were ward stock.
  
  
  RESULTS
  The study included 90 761 antibacterial doses. Of these, 6535 (7.2%) were documented as having been omitted; omission of 847 (0.9% of 90 761) was due to medication being unavailable. Non-restricted, ward stock antibacterials had the lowest frequency of omission, with 6.2% (271 of 4391) first doses omitted. The prevalence was 10.4% (27 of 260) for restricted, ward-stock antibacterials (OR = 1.6, 95% CI = 1.0-2.4, P = 0.027) and 15.5% (53 of 341) for non-restricted, non-ward stock antibacterials (OR = 2.7, 95% CI = 2.0-3.7, P < 0.001). Restricted, non-ward stock antibacterials had the highest frequency (30.7%, 71 of 231; OR = 6.2, 95% CI = 4.5-8.4, P < 0.001).
  
  
  CONCLUSIONS
  Antibacterials not stocked in clinical areas were significantly more likely to be omitted. The prevalence of omitted doses increased further if the antibiotic was also restricted. To achieve safe, effective antimicrobial use, a balance is needed between promoting antimicrobial stewardship and preventing unintended omitted doses.
authors: Pharmacy Department, Royal Cornwall Hospital NHS Trust, Truro, Cornwall TR5 0TJ, UK neil.powell@rcht.cornwall.nhs.uk.
authors: Neil
authors: N
authors: Powell
authors: Pharmacy Department, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London W6 9RG, UK UCL School of Pharmacy, London WC1N 1AX, UK.
authors: Bryony Dean
authors: BD
authors: Franklin
authors: Centre for Infection Prevention and Management, Imperial College, London, UK Centre for Medication Safety and Service Quality, Imperial College Healthcare NHS Trust, London W12 0HS, UK.
authors: Ann
authors: A
authors: Jacklin
authors: Pharmacy Department, Royal Cornwall Hospital NHS Trust, Truro, Cornwall TR5 0TJ, UK.
authors: Mike
authors: M
authors: Wilcock
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001424:Bacterial Infections / Q000188:drug therapy*; D004356:Drug Storage / Q000379:methods; D004363:Drug Utilization / Q000592:standards*; D055695:Electronic Prescribing / Q000592:standards*; D006761:Hospitals; D006801:Humans; D008508:Medication Errors; D012189:Retrospective Studies; D018570:Risk Assessment
chemical_list: D000900:Anti-Bacterial Agents