Improvement of Parenteral Antibiotic use in a University Hospital in Colombia

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Improvement of Parenteral Antibiotic use in a
University Hospital in Colombia
Pérez A, Dennis RJ, Rodriguez B, Castro AY,
Delgado V, Lozano JM

• Clinical Epidemiology and Biostatistics Unit,
  Pontificia Universidad Javeriana, Bogotá, Colombia

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ABSTRACT

• Problem Statement In Colombia, there has been no
  incentive in the past for continuing quality
  assessment, by ongoing monitoring, of antibiotic
  prescription practices.
• Objectives To evaluate the effect of an
  intervention to improve antibiotic prescribing
  practices in a University- based hospital.
• Design Quasi-experimental before/after study
  with a planned intervention interrupted time
  series analysis.
• Setting Tertiary care hospital caring for
  private and institutional patients.
• Study Population Hospitalized patient
  prescription census from 10 clinical services,
  including Gynecology and Obstetrics, Surgery,
  Medicine, and Pediatrics. A total of 2716
  prescriptions were collected between June, 1997
  and April, 2000.
• Intervention A structured antibiotic order form
  implemented between two data collection phases
  between week 82 and week 102. All hospitalized
  and prescribed patients completed the form since
  week 82.Physicians in charge of grup prescription
  in each service completed the forms. The Hospital
  designed the form with the help of the research
  tem. We also implemented an educational campaign
  with conferences for physicians and posters for
  all the clinical services, and blood pressure
  cuffs for anaesthesiologists.
• Outcome Measures Hospital weekly rate of
  incorrect prescriptions of (A) aminoglycosides in
  dose interval less than 24 hours (gentamicin,
  amikacin, streptomycin and netilmicin) (B)
  cephradine and cephalothin in dose interval
  greater than 6 hours (C) ceftazidime and
  cefotaxime in dose interval greater than 8 hours
  and (D) any antibiotic prescribed one hour before
  or after incision in surgery.
• Results Interrupted time series intervention
  analysis was conducted for three antibiotic
  groups of the hospitals weekly rate of incorrect
  prescriptions. Pre-intervention Auto-Regressive
  Integrated Moving Average (ARIMA) models were
  identified, estimated and diagnosed for the four
  time series (A,B,C,D). Time series (A) was an
  ARIMA (0,1,2) with corresponding estimates and
  standard error (SE) as theta10.36 (SE0.102) and
  theta20.49 (SE0.101), respectively. Time series
  (B) was an ARIMA (0,1,1) with corresponding
  estimate 0.82 and SE0.07. Time series (C) was
  an ARIMA (0,0,1) with corresponding
  estimate-0.72 and SE0.08. Time series (D) was
  an ARIMA (0,1,1). These models were used in the
  post-intervention series to test for pre-post
  series level differences. An abrupt constant
  change was significant in A, C and D time series,
  indicating a 47, 7.3 and 20 reduction on
  incorrect prescriptions after intervention.
• Conclusions High rates of incorrect prescription
  were reduced after the intervention. This
  intervention, consisting of both an educational
  campaign and introduction of a structured
  prescription form with built-in deterrents of
  selection of inappropriate dosing intervals, can
  be implemented in a teaching hospital in Latin
  America. Such an intervention leads to measurable
  decreases in the proportion of incorrectly
  prescribed antibiotics.

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BACKGROUND

• Uncontrolled use of antibiotics abuse and
  potential unwarranted events and costs
• Need for
• Ongoing monitoring of antibiotic prescription
  practices
• Implementation of interventions to improve
  inappropriate behavior
• Pharmacy and Infection Control Committees
  identified a critical area as
• Use of expensive antibiotics

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BACKGROUND

• Pharmacy and Infection Control Committees
  identified critical areas
• Use of expensive IV antibiotics
• Implementation of an adverse drug reaction
  surveillance program
• Use of sedatives and hypnotics
• Drug modification as a function of renal
  condition
• Adequate pharmacological prevention of UGI
  bleeding and thromboembolism

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RESEARCH OBJECTIVES

• To assess the appropriateness of the observed
  antibiotic prescription patterns.
• To implement a hospital wide intervention aimed
  to improve inappropriate practices.
• To assess the potential cost/savings profile of
  the intervention from the payer point of view.

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RESEARCH DESIGN
METHODS

• Quasi-experimental pre-post time series design
• Reasons for not using an RCT
• Permanent rotation of residents, interns and
  nurses very high potential for contamination bias
  within and between wards, which would attenuate
  any perceived effects
• Selection of one other hospital as control
  unfeasible control of measurable confounders

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SETTING

• San Ignacios Hospital, Bogotá, Colombia. June,
  1997
• Hospitalized patients
• Obstetrics-Gynecology, Surgery, Medicine,
  Pediatrics, Intensive Care Unit, others wards.

EXPERT PANEL

• PI, infectologist, representatives from GO,
  Pediatrics, Internal Medicine, Surgery and
  Nursing
• Identifying tracer conditions
• Developing expected norms regarding the
  appropriate use of antibiotics in selected
  conditions
• Developing data collection forms
• Delineating intervention

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INTERVENTION

• 1. Implementation of a new antibiotic order form
• 80 in US hospitals, 79 in British hospitals
• 2. Join educational intervention by researchers
  and infectologist (lectures and posters)
• 3. Logo bandblood pressure cuffs Do not forget
  the prophylactic antibiotic one hour before
  surgical incision.
• Started in January/1999

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OUTCOMES
Hospital weekly proportion of incorrect
prescriptions

• Incorrect prescription
• Dose interval lt 24 h
• Dose interval gt 6 h
• Dose interval gt 8 h
• Prescription gt 1 hour before and/or after
  incision

• Condition
• Aminoglycosides
• Cephradine/Cephalothin
• Ceftazidime/Cefotaxime
• Prophylactic prescription in surgery

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SAMPLE SIZE

• ? 0.05, two sided test
• ? 0.10
• ARIMA (2,0,0)
• ?1 0.3
• ?2 0.2
• 20 months of observation before and after
  intervention 80 weeks pre-post

Gottman JM (1981) Time series analysis. Cambridge
Univ. Press, 335-67
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HYPOTHESIS

• Abrupt Constant Change

• Abrupt Temporary Change

Stationary series (discrete and equally spaced
intervals)
Auto-regression process
Moving average process
Estimated from time series
Random shocks
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ETHICAL ISSUE

• Informing staff about prescription pitfalls
  outside the intervention period may produce
  temporary changes in habits that may attenuate
  results
• Data collector will not make staff aware of
  minor prescription errors
• Data collector will make staff aware of major
  prescription errors

STATISTICAL ANALYSIS

• Identification of pre-intervention ARIMA model
• Diagnosis checks over residuals
• Akaike Information Criterion
• No seasonal component expected
• SAS 6.12 TSO 51, Unix

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RESULTS
Antibiotic Order Form
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RESULTS 1.Aminoglucosides



Pre-Intervention ARIMA (0,1,2)

• Abrupt Constant Change was statistically
  significant.

-0.477 SE0.064 plt0.001
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RESULTS 2.Cephradine/Cephalothin


Pre-Intervention ARIMA (0,1,1)
Neither abrupt constant nor temporary change
were statistically significant.
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RESULTS 3.Ceftazidime/Cefotaxime
Pre-Intervention ARIMA (0,0,1)
Abrupt Constant Change was statistically
significant.
-0.073 SE0.03 plt0.05
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RESULTS 4.Prophylactic P. in Surgery
Pre-Intervention ARIMA (0,1,1)
Abrupt Constant Change was statistically
significant.
-0.199 SE0.069 p0.004
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DISCUSSION

• This study confirms previous reports of
  reductions in the proportion of incorrect
  antibiotic prescriptions by use of an educational
  campaign and a structured antibiotic order form.
• We believe that our structured prescription form
  improved the quality of the prescriptions by
  increasing the awareness of physicians about
  correct dose intervals which is consistent with
  previous studies reported in the literature.

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DISCUSSION

• Reduction in incorrect
• Prescriptions
• 47 Aminoglycosides
• 7.3 Ceftazidime
• Cefotaxime
• 20 Prophylactic P. in
• surgery

• No enough reduction in Prophylactic Prescriptions
  in Surgery.
• RCT not feasible due to permanent rotation of
  residents/nurses, etc.
• Ethical Issue informing staff about prescription
  pitfalls.

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ACKNOWLEDGMENTS

• This work was supported by INCLEN, INC (grant
  1004-97-6501) and Pontificia Universidad
  Javeriana (grant 12-24-01-31).