Download Practical Antibiotic Prescribing

Practical Antibiotic Prescribing &
Antibiotic Awareness
Berny Baretto (Antibiotic Pharmacist)
5th February 2015
Contents
•
•
•
•
•
•
•
•
•
Antibiotic Awareness
Why is it important?- Background
How to prescribe an antibiotic
New Antibiotic Policy 2015
Audit
What must be included in an antibiotic prescription
Practical examples
Gentamicin Prescribing
Summary
European Antibiotic Awareness Day- campaign
to promote prudent antibiotic use(18th
November 2014, supported by DOH)
Key Messages
• It is a public health initiative aimed at encouraging
responsible use of antibiotics
• Lack of new antibiotics being developed especially to
cover gram negative bacteria.
• Number of infections due to antibiotic–resistant bacteria
is growing
• Important to preserve the use of the antibiotics currently
available eg carbapenems
Background contd-Use selects
Resistance
• Acquired resistance absent from bacteria collected pre1940
• Resistance repeatedly followed introduction of new
antibiotics
• Resistance greatest where use heaviest
• Resistant mutants selected in therapy
Β-Lactam use & resistance in
S.pneumoniae
→
Low rates of antibiotic use = low
resistance
Bronzwaer et al Emerg Infect Dis. 2002; 8:278-82
How to prescribe an antibiotic –why is it
important
• Department of Health Guidelines-(Advisory Committee on
antimicrobial resistance and healthcare associated Infection)-Nov
2011
• Antimicrobial stewardship- “start smart-then focus”• Want :
• Right Drug
• Right Dose
• Right Time
• Right Duration
• For Every Patient
Start Smart Is :
• Don’t start antibiotics in the absence of clinical evidence
of bacterial infection
• If there is evidence or suspicion of bacterial infectionuse local antibiotic guidelines to start treatment
• Document on drug chart Indication, duration/review
date, route & dose
• Obtain cultures first
• Prescribe single dose antibiotics for surgical
prophylaxis-where proven efficacy
Then Focus is:
• Review clinical diagnosis and the continuing need for antibiotics by
48 hours and make a clear plan of action- “the antimicrobial
prescribing decision”
• 5 options
• 1. STOP
• 2. Switch i/v to oral
• 3. Change –ideally to narrower spectrum or broad if needed
• 4. Continue (review again at 72 hours)
• 5. Outpatient Parenteral antibiotics therapy (OPAT)
• Make sure review and decision is clearly documented in medical
notes.
Prompt I/V to oral switch
• All I/V antibiotics should be reviewed at 48 hours and
changed to oral where clinically appropriate.
• Advantages
• It reduces the likelihood of I/V related infections
• It reduces potential discomfort for patients on I/V therapy.
• It allows more timely administration of antibiotics for the patient.
• It helps to facilitate a prompt discharge for patients
• It is quicker for administration, saving nursing time and therefore
there is a potential cost saving too.
• It potentially reduces overall treatment costs
Department of Health Guidance-Antibiotic
Stewardship
Good Prescribing Practice
• Promotes Good Prescribing Practice- no missed doses,
ensures continuity in care
• Adherence to Trust Antibiotic Policy
• Helps to Reduce Incidence of Clostridium difficile
Infection
• Audit
New Antibiotic Policy 2015
• 1. New allergy section eg abdominal infections: cholangitis
Standard
Penicillin
Penicillin
treatment
anaphylaxis
allergy
Pip/taz 4.5g tds Meropenem 1g
i/v
tds i/v
Cipro 500mg bd
po+ met 500mg
tds i/v
• 2. Oral switch/stepdown
• Eg SBP in cirrhosis
• Piperacillin/tazobactam 4.5g tds i/v →co-amoxiclav 625mg tds po
Other Guidelines
• 1. Neurosurgical guidelines
• 2. Use of gentamicin
• 3. Use of teicoplanin
• 4. Use of vancomycin
• (linked to main policy)
• 5. Clostridium difficile
• 6. Prophylaxis Policy
• (separate Policies)
Clostridium difficile guideline
• 1. Information on diagnosis and laboratory
findings(interpretation of test results)
• 2. General considerations
• Stop antibiotics, review PPIs, fluid balance etc
• 3. Treatment options
• Metronidazole use -1st line
• High dose vanc (orally)
Prophylaxis Policy
• Antibiotic prophylaxis at an appropriate dose and time reduces
the frequency of surgical site infections.
• For optimum efficacy, intravenous antibiotics should be
administered within 60 minutes of the skin being incised and as
close to time of surgical incision as practically possible.
• Single doses of antibiotics must be prescribed for surgical
prophylaxis where antibiotics have been shown to be effective.
• A repeat dose of antibiotic is required in prolonged procedures
and where there is significant blood loss.
Quarterly Audit-(overall Trust Data)
General
Antibiotic
Data
Dec-13
Mar-14
Jun-14
Sep-14
% Patients
on
antibiotics
36%
30%
31%
29%
% IV
Antibiotics
57%
58%
57%
62%
% Oral
Antibiotics
43%
42%
43%
38%
Specific Antibiotic Monitoring
Dec-13
Mar-14
Jun-14
Sep-14
%i/v >48hrs
56%
57%
51%
50%
%>5days but ≤ 7
days
10%
10%
8%
10%
% > 7 day course
14%
15%
12%
15%
% > 7 day course
appropriate
100%
95%
100%
98%
% Patients with
allergy status
documented
90%
78%
85%
86%
% Indication
stated
70%
73%
76%
84%
% antibiotics
prescribed
appropriately when
indication stated
99%
98%
98%
93%
% course length
or review stated
48%
53%
58%
63%
• PRACTICAL EXAMPLES
What must be included in an antibiotic
prescription-Documentation of allergy status
UTI Recommendation
Uncomplicated Cystitis
Crossing off an Antibiotic
Re-prescribing after antibiotic
sensitivities appear on CRRS
Chest Infection Recommendation
Query Non-severe CAP
Gentamicin Prescribing
• 5 steps for safe gentamicin
prescribing
• Usually gentamicin is only required for 24-48hrs.
• Course lengths for gentamicin should not exceed 5
days unless Microbiology have approved its use for
extended durations (this may be indicated in some
infections eg Endocarditis).
1. Weigh Patient:
• Weigh patient. If weighing is not possible, estimate
weight using ideal body weight formulae (based on
height and gender).
• For obese patients ≥BMI 30 use formula for dosing
weight.-see below.
Equations for Ideal Body weight and Obese
dosing
•
•
•
•
•
•
Imperial
Ideal Body weight (Male) = 50 + (2.3 x inches over 5 feet)
Ideal Body weight (Female) = 45.5 + (2.3 x inches over 5 feet)
Or
Metric
Ideal Body weight (Male) = 50kg + 0.9kg for each cm above 150cm in
height
• Ideal Body weight (Female) = 45.5Kg + 0.9kg for each cm above 150cm
in height
• For Obese Patients (≥BMI 30) use obese dosing weight calculation5 :
• Obese Dosing Weight (in Kg) = ideal body weight + 0.4 (actual Body
weight – ideal body weight)
2. Calculate gentamicin Dose :
• Calculate the gentamicin dose using 5mg/Kg
(maximum 400mg od)
• a)If normal body weight - use actual body weight
value
• b)If Obese (≥BMI 30)- use obese dosing weight
• c) if weight unobtainable – calculate ideal body weight
3. Calculate creatinine clearance (CrCl) :
• Calculate the creatinine clearance using Cockcroft and Gault equation
• Creatinine =
• clearance
(140-age in years) x weight in Kg(from step 1) x F
Serum Creatinine (in micromole/Litre)
• F=1.04 (female) or F=1.23 (male)
4. Check dosing Interval and when levels
need to be done :
Work out the dosing interval and when levels should be checked
Creatinine
Clearance
Dose Interval
Pre-dose level
check
> 60ml/min
24 hourly
Before 2nd/3rd dose
41-60ml/min
36 hourly
Before 2nd/3rd dose
21-40ml/min
48 hourly
Before 2nd dose
< 21ml/min
> 48 hourly
Check level after
48 hours
5. Check gentamicin serum level
• If pre-dose gentamicin level is 1mg/L or less continue
the original dosing regime
• If pre-dose gentamicin level is greater than 1mg/L,
check guideline for further information regarding
interpretation or consult Microbiology/ Pharmacy for
advice.
Documentation on Medicine Chart
SUMMARY
• 1. Antibiotic Awareness
• 2. What to include when prescribing an antibioticpractical examples
• 3. Why do we document this- The background
• 4. New Antibiotic Policy 2015
• 5. Antibiotic Audit
• 6. Gentamicin prescribing