La
b
or
t
a
or
ults
s
e
yR
National
Services
Scotland
Risk
Fac
to
rs
ty
Clinical Data
Demographics
ici
i
vi
M
ed
ne
s Us
e
Hea
ar
c
h
lt
e
t
c
A
Infection
intelligence
platform.
Investigating Orthopaedic
Surgical Prophylaxis Changes
and Post-operative Acute
Kidney Injury in NHS Grampian
using NHS Scotland’s Infection
Intelligence Platform.
Background
Results
To support reduction of Clostridium difficile infection (CDI) in 2008 the Scottish
Antimicrobial Prescribing Group recommended that all NHS boards in Scotland
restrict the use of antibiotics associated with a high risk of CDI. In NHS Grampian
the policy for antibiotic prophylaxis in orthopaedic surgery was changed in June
2010 (table 1). Previous studies have found similar policy changes resulted in an
increase in post-operative acute kidney injury (AKI).
Change in AKI rate - Interrupted time series analysis
Aim
To use individual level linked data to examine rates of post-operative AKI before
and after antibiotic prophylaxis policy change in NHS Grampian and to assess any
subsequent changes in post-operative CDI rates.
3,870 trauma cases and 5,475 elective cases were examined. There was a
significant increase in AKI rate following the policy change (ß=0.28; 95% CI 0.03
to 0.53; p=0.028) in trauma patients, equating to an increase of 0.28 cases of AKI
per 100 procedures per month and a relative intervention effect at 24 months of
150% (95% CI 25% to 250%).There was no significant change in AKI rate amongst
elective patients.
Figure 1:
25%
% AKI
Methods
NHS Grampian Orthopaedic antibiotic prophylaxis policy June 2010
Recommended
antibiotic
Trauma – internal fixation
Elective - arthroplasty
or arthroplasty
Pre-policy
Post-policy
Pre-policy
Post-policy
change
change
change
change
flucloxacillin (2g) flucloxacillin (1g) flucloxacillin (2g)
cefuroxime
OR
AND
OR
(1.5g)
co-amoxiclav
gentamicin
co-amoxiclav
(1.2g)
(1.5mg/kg)
(1.2g)
OR
cefuroxime
(1.5g)
Policy change
15%
10%
5%
-0
De 8
c08
Fe
b09
Ap
r-0
Ju 9
n09
Au
g09
O
ct
-0
De 9
c09
Fe
b10
Ap
r-1
Ju 0
n10
Au
g10
O
ct
-1
De 0
c10
Fe
b11
Ap
r-1
Ju 1
n11
Au
gO 11
ct
-1
1
De
c11
Fe
b1
Ap 2
r-1
2
ct
08
O
g-
Au
08
0%
Ju
n-
Segmented regression analyses of interrupted time series were used to evaluate
changes in level and trend associated with the intervention and estimate effect
sizes. Incident rate ratios were used to examine any changes in post-operative CDI
rates.
Modelled % AKI
20%
% AKI
Hospital activity data (SMR01) were used to identify NHS Grampian patients who
underwent an orthopaedic surgical procedure during the period 01 June 2008
to 31 May 2012 and cases were stratified into trauma and elective. Cases were
linked to local NHS Grampian creatinine data to detect post-operative AKI and
were further linked to patient-level national data: (i) hospital activity data (SMR01)
to create the Charlson score for comorbidity, (ii) community prescribing data
from the Prescribing Information System(PIS) to identify previous exposure to
any medicines which predispose to renal impairment, (iii) infection data from the
Electronic Communication of Surveillance in Scotland (ECOSS) to identify any
post-operative CDI, (iv) mortality data from the National Records for Scotland (NRS)
and (v) Scottish Renal Registry data for case exclusion purposes. All data were
linked using the CHI as the unique patient identifier.
Table 1:
Post-operative acute kidney injury in orthopaedic trauma patients in NHS
Grampian
Month/Year
Post-operative CDI
Reductions in post-operative CDI were seen in both elective and trauma cases but
were only statistically significant in the trauma group, from 14.70 to 5.29 cases of
post-operative CDI per 1,000 procedures (incident rate ratio = 0.36 (95% CI 0.180.74)).
Conclusion
We found that a change in orthopaedic antibiotic prophylaxis policy in NHS
Grampian to flucloxacillin plus gentamcin was associated with an increase in postoperative AKI in trauma patients. This is consistent with observations in other
boards and supports the new recommendation away from this policy made by
SAPG in 2012. This large, population based study - an exemplar study for NHS
Scotland’s Infection Intelligence Platform - has also demonstrated novel data
linkage been an individual NHS board biochemistry data and national datasets.
Authors
Charis Marwick
Eilidh Fletcher Jacqueline Sneddon Gwen Bayne Andrea Patton |
|
|
|
|
IIP Clinical Lead, NHS National Services Scotland
Senior Information Analyst, Information Services Division
Project Lead for SAPG, Scottish Medicine Consortium
Principal Information Analyst, Information Services Division
Advanced Information Analyst, Scottish Medicine Consortium