Transcript How to Avoid prescribing Errors

Safe prescribing:
How to avoid prescribing errors
Maggie Allen
UHCW/CWFS
Aims
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To provide an awareness of:
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Common medication errors
How to minimise these
National and local resources available
to you to aid in safer prescribing
To give you some prescribing
pointers to look out for in posts
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By the end of the session you
should be able to:
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Define a medication error
List the ‘Five Rights’
Identify common types of medication
errors
Begin to think about how to minimise
errors by using your knowledge, skills
and available resources
During your placements
Think about:
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What do I need to prescribe in a safe
way?
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Patient information
 Co-morbid conditions
Drug information
 Pharmacology
Pharmacokinetics and pharmacodynamics
 Therapeutics
Systems
 Policies, guidelines, prescribing aids etc
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What is an error?
What is an error ?
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Doses omitted
Wrong dose
Unprescribed drug
given
Wrong dosage form
given
Wrong route of
administration
Wrong rate of
administration
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Wrong time of
administration
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time of day
in relation to food
etc....
Using
unstable/expired drug
Wrong administration
technique
Incorrect
reconstitution
Extra dose given
Where do errors occur in the process of
giving a drug?
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Prescribing
Dispensing
Administration
Counselling/communication
Adverse events in hospitals
What is the size of the problem?
Adverse events per
admission (%)
10%
AE number / year in UK
850,000
Cost in additional hospital
stay (£)
£2 billion
Cost of clinical negligence
schemes/yr
£400 million
Medication errors = % of
incidents
25%
An organisation with a memory. Dept of Health 2001
Reported incidences
Difficult to estimate due to varying
definitions - US/UK
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Prescribing errors
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Medication errors
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3-20 per 1000 prescriptions
1 per patient per day
Been estimated that drug errors account
for 1/5 of all deaths due to adverse drug
events
Outcomes
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Data collated by US
National Co-ordinating
council for Medication
Error Reporting and
Prevention 1993-98
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Performance deficit
29.8%
Communication
problem 15.8%
Knowledge deficit
14.2%
Dose miscalculation
13%
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5366 reports
68.2%- Serious
patient outcomes
9.8% - fatal
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Phillips, J etal. Am J Health Syst Pharm 2001;58: 1835-41
Improper dose
Wrong drug
Wrong route of
administration
Prescribing errors
Process
Error Rate
Prescribing errors
(Primary Care)
Computer generated
7.9%
Prescribing errors
(Primary Care)
Hand written
10.2%
Prescribing errors
(Hospital)
1.5%
Serious
Errors
0.4%
Dean B, Schachter M, Vincent C, Barber N. Quality and Safety in Healthcare 2002; 11:340-344
Shah SNH, Aslam M and Avery AJ. Pharm J. 2002; 267: 860-862
Handwriting
Errors in medication history taking
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Literature review
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22 studies, 3755 patients
Errors in medication histories
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In up to 67% of cases
10-61% had at least 1 omission error
54% of patients had at least 1
medication history error
Clinically important errors in 11-59%
Tam et at Canadian Medical Association Journal 2005;173(5):510-15
Dispensing and adminn errors
Stage of process
Error Rate
Serious
Errors
Dispensing errors
(P)
1%
0.18%
Dispensing errors
Undetected (H)
0.0002
Administration
Oral Medicines (H)
3 – 8%
Preparation and
admin of
parenteral
medicines
13%- 49%
UK references 1 – 12 from Building a safer NHS, Medication Safety
1%
Similar packaging
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Same drug – different manufacturers
Similar packaging
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Same drug – several strengths
May be colour-coded but DO NOT rely on
colour
Similar packaging
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Similar sounding names / similar spelling /
same strength
Ceftazidime – Cefotxime
Similar packaging
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If in a hurry – These look similar
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Water for injection, Sodium Chloride injection
So does Potassium 15% injection = Why there
are NPSA/Trust policy on restricting this
Summary:
Common error types
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Wrong patient
Contra-indicated medicine
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Allergy, medical condition, drug-drug
interaction
Wrong
Wrong
Wrong
Wrong
Wrong
drug / ingredient
dose / frequency
formulation
route of administration
quantity
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Poor handwriting on Rx
Incorrect IV administration
calculations or pump rates
Poor record keeping/checking
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double doses
wrong patient
Paediatric doses
Poor administration technique
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Complicated prescriptions
Calculations
Verbal orders
Lack of knowledge about drugs
Mistakes in identifying drugs
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names
packaging
misreading
National & local examples
Discharged on
warfarin loading
dose 10mg od
Not referred for dose
adjustment to clinic
14days of 10mg od
INR 12.3
Admitted with frank
haemorrhage
Weight-related dose Patient was 51kg,
for tinzaparin – 80kg risk of haemorrhage
estd
Rx: Ranitidine 50mg Given via epidural
line rather than
central line
Discharged on
Not referred for dose
warfarin loading dose adjustment to clinic
10mg od
14days of 10mg od
INR 12.3
Admitted with frank
haemorrhage
Weight-related dose
for tinzaparin – 80kg
estd
Rx: Ranitidine 50mg
Patient was 51kg,
risk of haemorrhage
Given via epidural
line rather than
central line
CABG patient,
standard therapy
Thyroxine missed on
admission,
discovered day 10
Galantamine restarted after a gap,
Rx; 8ml qds
Should have been
12mg (2ml) bd
Rx: Co-amoxiclav
Did not realise this is
a penicillin
Penicillin-alllergic
prescriber confused
over liquid strength
anaphylaxis
Anaesthetist adjusted New pump.
rate of fentanyl
Increased rate x
syringe pump in
1000
Theatre
Respiratory arrest death
Rx: morphine 0.4ml
4ml given
30% sodium chloride Severe pain
used instead of 0.9%
to dilute an epidural
In Theatre: Sodium
chloride flush for a
central line switched
with fentanyl
Respiratory arrest.
Syringes made up in
advance and not
labelled
IV line flushed with
sodium chloride
0.9%
Was in fact
Potassium 15%
→ death
Ampoules look similar in
design
Case study 1 – "Cambridge"
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Rx Methotrexate 17.5mg once a
week
New Rx 10mg once a day
10mg daily dispensed by locum
pharmacist
Rx error noticed by 2nd GP, but the
computer record was not altered
+5/7 patient admitted to ENT ward
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Drug chart written for 100mg daily
+1/7 Nurse d/w patient – back to
10mg od
+1/7 Pharmacist queries and asks
nurse to ask Dr to check dose
GP records confirm 10mg od
+2/7 blood tests re-checked } Haem
+5/7 patient dies
Case study 2 – “Nottingham”
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Rx Intrathecal methotrexate under
GA in theatre by Oncology Reg &
intravenous vincristine on ward by
specialist nurse
"Outlied" on non-specialist ward
Both drugs delivered to theatre from
ward
Given food pre-op – op postponed
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Orignal SpR off-duty now
Cover SpR unable to leave ward,
anaesthetist to admin intrathecal drug
Anaesthetist had given I/Thecal drugs
before but had never given
chemotherapy
Methotrexate given intravenously
Vincristine given intrathecally
Patient died
Improving medication safety
Department of Health. Jan 2004
Improving medication safety:
Main areas of medication error
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Anaesthetic practice
Anticoagulants
Cytotoxic drugs
Intravenous infusions
Methotrexate
Opiate analgesics
Potassium chloride
Causes → Solutions
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Lack of knowledge of
the drug – 31%
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“rule” violations – 10%
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Wrong dose, choice,
drug.
Interaction
Allergy checking
Incl. communication
problems
“Slip” or memory loss –
9%
Leape et al. JAMA 1995;274:35-43
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Drug information
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Eg: Interactions
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Resources available
Patient condition
Renal / liver function
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Guidelines, formulary
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Avoiding errors
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Patient knowledge
Have a therapeutic goal
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Is prescribing the right answer?
Have you included the patient in this decision?
Knowledge about the drug
Monitor for effects and adverse effects
Use your resources
Good communication
Taking a good medication history
How reliable is your source – does it have
enough detail?
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Drug details
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Patient, patient’s repeat prescription, own drugs,
GP admission letter, on-call service
dose, frequency, formulation (eg modified
release), start date, indication
Include: Prescribed drugs, ‘OTC’ drugs,
complementary medicines, vitamins,
? ‘Recreational drugs’
Allergies including severity
Compliance
Therapeutic failures
Factors affecting a drugs pharmacodynamics
or pharmacokinetics
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Children
The elderly
Renal impairment
Hepatic impairment
Prescribing in pregnancy or breast feeding
Drug interactions
More later…..
Further references:
Clinical Pharmacology textbook – use course recommendation
Basic Clinical Pharmacokinetics. 4th edn. ME Winter. Covers Drug-specific
kinetics eg Digoxin, gentamicin
Drug dosing in renal impairment
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Based on estimation of renal
function using creatinine clearance
Cockcroft-Gault equation
Crcl = F x (140-age)x wt in kg
S.Cr in micromol/L
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Where F = 1.23 for males, 1.04 for females
Or use an on-line calculator such as
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http://www.kidney.org/professionals/kdoqi/gfr_c
alculator.cfm
Drug-drug interactions
drug-food interactions
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Resources
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BNF Appendix 1
Pharmacy Medicines Information
Departments
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Have specialists texts and other
resources to help
Resources available to you
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Summary of Product Characteristics
for each medicine - eMC
Pharmacy Medicines Information
On-line
National
Electronic prescribing
Other medical and non-medical
prescribers
Pharmacy
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Avaliable for help and advice
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Ward Pharmacist
Local Medicines Information
department
Regional medicines Information
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Mainly Community sector enquiries
Out-of-hours: On-call or resident
pharmacist
Electronic Medicines Compendium (eMC)
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The eMC provides up-to-date information
on licensed UK medicines
http://emc.medicines.org.uk/
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Summary of Product Characteristics (SPCs)
Patient Information Leaflets (PILs).
SPCs are legal & technical documents
with information to help guide on the best
way to use a medicine.
In summary
Prescribing responsibilities
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Drug
Dose
Route
Rate of administration
Duration of treatment
Checking patient allergies &
sensitivities
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Providing a prescription that is:
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Legible
Legal
Signed
Giving all information to allow safe
administration
Hints
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Clear and
unambiguous
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Care with units
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Legal
Approved name
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No abbreviations
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Care with IVs
Is it weight/BSArelated dosing. Is
weight accurate?
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Clear decimal
points
0.5ml not .5ml
Rewrite charts
regularly
Take time, eg
to read labels
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Avoid
abbreviations
od / bd / tds /
qds
Not 250mg3
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Take particular care if:
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Impaired renal function
Hepatic dysfunction
Children
The elderly
Drug is unknown to you
Very new drug 
Remember the “Five Rights”
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•
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the
the
the
the
the
right
right
right
right
right
patient
drug
time
dose
route
If in doubt ……..
Ask
Further reading & resources
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Naylor, R. Medication Errors.
Radcliffe Press. ISBN 1857759567
Department of Health. (2004).
Building a safer NHS. Improving
medication safety.
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http://www.dh.gov.uk/PublicationsAndStatist
ics/Publications/PublicationsPolicyAndGuidan
ce/PublicationsPolicyAndGuidanceArticle/fs/e
n?CONTENT_ID=4071443&chk=PH2sST
National Patient Safety Agency
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Website:
http://www.npsa.nhs.uk/
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National Prescribing Centre
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Website:
http://www.ismp.org/
National Electronic Library for Medicines
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http://www.npc.co.uk/
Institute for Safe Medication Practices
(ISMP) (American)
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Website:
Website:http://www.druginfozone.nhs.uk/hom
e/default.aspx
Aronson & Richards. Oxford Handbook of
Practical Drug Therapy. ISBN 0198530072