Transcript presentation

High dose methadone prescribing and medical review: a
completed audit cycle in Midlothian 2012-14.
Dr Rachel XA Petrie, Consultant Psychiatrist in Addictions, MBChB BSc(Hons) MRCPsych PhD
Midlothian Substance Misuse Service, 1/5 Duke Street, Dalkeith, Midlothian EH22 1BG
Results
Background
QTc prolongation on the ECG is associated with
arrhythmias and sudden cardiac death. Methadone is a
risk factor for QTc prolongation on the ECG, with a
possible dose-dependent action, but the overall risk is
low 1. However, patients on high dose methadone often
have other QTc risk factors. These include co-morbid
diagnoses and other commonly prescribed
psychotropic medications. This is one reason why
regular medical review of patients on high dose
methadone is important within Addiction services. No
robust system was in place within our service to
ensure this.
Aims
• To establish a baseline of current practice of medical
reviews in high dose methadone patients (2012).
• To feedback data on current practice to keyworkers,
and to make recommendations for improvement
• To re-audit the same parameters in the same service
(2014) in order to establish whether this had led to any
quality improvement.
Method
The case notes of patients on high dose methadone
(defined as methadone ≥ 100mg/day), were reviewed to
collect the following data at baseline (2012):
• Number of patients on high dose methadone; age
• dose
• whether medical review within last 6 months
• co-morbid conditions
• other prescribed drugs (including GP prescriptions)
• whether ECG requested
• whether patient attended for ECG
• whether ECG QTc was prolonged
• whether prescription altered as a result of ECG (or other
reason)
These results (along with QTc education) were presented
to keyworkers. It was recommended that all high dose
patients were offered and ECG and 6 monthly medical
reviews.
The same data was collected for re-audit in 2014.
Prolonged QTc?
Nov 2014
Discussion/Conclusions
The results are summarised in the table below. The total
number of high dose prescriptions is around 10% of the
total number of patients in our service. Compared to 2012,
the re-audit in 2014 shows a reduction in the number of
high dose methadone prescriptions and a reduced mean
daily dose. A slightly higher percentage were medically
reviewed within 6 months, and there was better recording of
co-morbid conditions and other prescriptions. There were a
few more ECG requests but attendance for ECG remained
poor. Few patients had QTc prolongation in either baseline
or repeat audit. Prescriptions changes were more often
made for other clinical reasons rather than as a direct result
of ECG.
2012
Number of high dose 28
prescriptions
Mean age
32 years
Mean dose
129mg daily
Medical review in last Yes
18/28 = 64%
6 months?
No
10/28
Co-morbid physical Yes
12/28 = 43%
diagnoses clear?
No
15/28
Unclear 1/28
Co-morbid nonYes
5/28 = 18%
addiction psychiatric No
6/28
diagnoses clear?
Unclear 17/28
All prescriptions
Yes
14/28 = 50%
clear (including from No
14/28
GP)?
ECG request last six Yes
9/28 = 32%
months?
No
19/28
ECG attended last six Yes
5/9 = 56%
months?
No
4/9
[email protected]
2014
20
35.5 years
120mg daily
Yes
14/20 = 70%
No
6/20
Yes
15/20 = 75%
No
5/20
Unclear 0/20
Yes
8/20 = 40%
No
9/20
Unclear 3/20
Yes
10/20 = 50%
No
10/20
Yes
7/20 = 35%
No
13/20
Yes
2/7 = 29%
No
3/7
Unclear 2/7
No
1/2
Result awaited 1/2
None
Yes
2/28
No
3/28
Prescription altered 1 of 2 who had
as result of prolonged prolonged QTc
QTc ECG?
Prescription altered 2 others who attended None
for other clinical
for ECG
reason?
This completed audit cycle has led to several
improvements in quality of care.
Both patients and keyworkers are more informed of the
potential cardiac risks of a high dose methadone
prescription. The importance of regular medical
review/discussion within the Addictions service is more
recognised. Consequently, the opportunity for medication
review to ensure safest prescribing is now more routine
for these patients.
At re-audit, there were fewer high dose prescriptions, a
reduced mean daily dose. Recording of co-morbid
conditions and other prescriptions also improved. It is
recognised that updated GP prescription information is
important and it is likely that improving IT systems will
help this. All these factors are highly relevant in relation to
safe prescribing.
Medical review and discussion appropriately leads to ECG
requests. As expected, the data shows that attendance for
ECG is poor in this population. ECG monitoring of all high
dose methadone patients is therefore impractical, and is
probably of dubious benefit1.
These data confirm that prescription changes are more
often made for other clinical reasons rather than as a
direct result of ECG. This is in line with the Maudsley
Prescribing Guidelines 1 which state that “prescribing
should be such that the need for ECG monitoring is
minimised”. Cardiac and other risks can be reduced
through other clinical strategies at medical review.
It is intended that this audit will be repeated over time and
in other geographical areas in the Substance Misuse
Directorate within NHS Lothian.
Bibliography
1. Maudsley Prescribing Guidelines (9th ed). Taylor D., Paton
C., Kerwin R. (2007) Informa healthcare: 116-119.