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12 International Taskforce on Anaesthesia
Safety. International standards for a
safe practice of anaesthesia. European
Journal of Anaesthesiology 1993;10
(Suppl. 7):12–15; updated: http://
www.anaesthesiologists.org/en/latest/
2008-international-standards-for-asafe-practice-of-anaesthesia.html
(accessed April 7 2009).
13 Pedersen T, Dyrlund Pedersen B,
Moller AM. Pulse oximetry for perioperative monitoring. The Cochrane
Database of Systematic Reviews 2003; 3:
CD002013.
14 Smith GC, Pell JP. Parachute use to
prevent death and major trauma
related to gravitational challenge:
systematic review of randomised
controlled trials. British Medical Journal
2003; 327: 1459–61.
15 Sackett DL, Rosenberg WM, Gray
JA, Haynes RB, Richardson WS.
Evidence based medicine: what it is
and what it isn’t. British Medical Journal
1996; 312: 71–2.
16 Moller JT, Pedersen T, Rasmussen
LS, et al. Randomized evaluation of
pulse oximetry in 20,802 patients: I.
Design, demography, pulse oximetry
failure rate, and overall complication
rate. Anesthesiology 1993; 78: 436–44.
17 Moller JT, Johannessen NW, Espersen
K, et al. Randomized evaluation of
pulse oximetry in 20,802 patients: II.
Perioperative events and postoperative
complications. Anesthesiology 1993; 78:
445–53.
18 Cooper JB, Newbower RS, Long
CD, McPeek B. Preventable anesthesia mishaps: a study of human
factors. Anesthesiology 1978; 49: 399–
406.
19 Cooper JB, Newbower RS, Kitz RJ.
An analysis of major errors and
equipment failures in anesthesia management: considerations for prevention and detection. Anesthesiology
1984; 60: 34–42.
20 Bierman MI, Stein KL, Snyder JV.
Pulse oximetry in the postoperative
care of cardiac surgical patients. A
randomized controlled trail. Chest
1992; 102: 1367–70.
21 Moller JT, Jensen PF, Johannessen
NW, Espersen K. Hypoxaemia is
reduced by pulse oximetry monitoring
in the operating theatre and in the
recovery room. British Journal of
Anaesthesia 1992; 68: 146–50.
22 Cote CJ, Goldstein EA, Cote MA,
Hoaglin DC, Ryan JF. A single-blind
study of pulse oximetry in children.
Anesthesiology 1988; 68: 184–8.
23 Cote CJ, Rolf N, Liu LM, et al. A
single-blind study of combined pulse
oximetry and capnography in children. Anesthesiology 1991; 74: 980–7.
24 Cullen DJ, Nemeskal AR, Cooper JB,
Zaslavsky A, Dwyer MJ. Effect of
pulse oximetry, age, and ASA physical
status on the frequency of patients
admitted unexpectedly to a postoperative intensive care unit and the
severity of their anesthesia-related
25
26
27
28
29
30
31
complications. Anesthesia & Analgesia
1992; 74: 181–8.
Runciman WB, Webb RK, Barker L,
Currie M. The pulse oximeter:
applications and limitations – an
analysis of 2000 incident reports.
Anaesthesia and Intensive Care 1993; 21:
543–50.
Runciman WB. Iatrogenic harm and
anaesthesia in Australia. Anaesthesia &
Intensive Care 2005; 33: 297–300.
Cheney FW, Posner KL, Lee LA,
Caplan RA, Domino KB. Trends in
anesthesia-related death and brain
damage: a closed claims analysis.
Anesthesiology 2006; 105: 1081–6.
Eichhorn JH. Prevention of intraoperative anesthesia accidents and
related severe injury through safety
monitoring. Anesthesiology 1989; 70:
572–7.
Holland R, Webb RK, Runciman
WB. The Australian Incident Monitoring Study. Oesophageal intubation:
an analysis of 2000 incident reports.
Anaesthesia & Intensive Care. 1993; 21:
608–10.
McGlynn E, Asch S, Adams J, et al.
The quality of health care delivered to
adults in the United States. New
England Journal of Medicine 2003; 348:
2635–45.
Walker IA, Merry AF, Wilson IH,
et al. Global oximetry: an international anaesthesia quality improvement project. Anaesthesia 2009; 64:
1051–1060.
Editorial
Pre-operative coronary
revascularisation before
non-cardiac surgery: think
long and hard before making
a pre-operative referral
Many of us use the ‘American College
of Cardiology ⁄ American Heart Association (ACC ⁄ AHA) 2007 Guidelines on
Perioperative Cardiovascular Evaluation
and Care for Noncardiac Surgery’, to
inform our practice [1]. These guide-
1048
lines are downloadable free from http://
circ.ahajournals.org and propose that
there are no clear cut indications for
coronary revascularisation before noncardiac surgery. Coronary revascularisation may be useful in patients in whom
it would be indicated in the absence of
surgery; for example those with stable
angina and left main stem disease, stable
angina and triple vessel disease (particularly if the left ventricular ejection
fraction is < 50%), unstable angina
and ⁄ or acute ST-elevation myocardial
infarction (MI). However, in most
cases, coincidental findings suggesting
asymptomatic coronary artery disease
are probably best left alone.
In this edition of Anaesthesia, Biccard
and colleague [2] have systematically
reviewed randomised controlled trials of
pre-operative coronary revascularisation
for vascular surgery and conclude that
there is no advantage with pre-emptive
revascularisation and there may be
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Journal compilation 2009 The Association of Anaesthetists of Great Britain and Ireland
Anaesthesia, 2009, 64, pages 1045–1050
Editorial
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considerable harm, as pre-operative
angioplasty was associated with
increased 30 day MI and composite
death and MI. Their methodology
identified 235 papers which filtered
down to just two that met their inclusion criteria. Only prospective randomised trials of pre-operative coronary
revascularisation that reported mortality
and non-fatal MI in patients undergoing
vascular surgery were included. The
two trials meta-analysed were the Coronary Artery Revascularisation Prophylaxis Study (CARP) and the more
recently published Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echo (DECREASE-V).
Between the two trials a total of 7739
high cardiac risk patients were screened,
from which 621 were randomised to
receive pre-operative revascularisation,
or not. So what does this systematic
review add to the existing literature?
Well, CARP and DECREASE-V considered ‘coronary revascularisation’ by
coronary artery bypass grafting (CABG)
or percutaneous coronary interventions
(angioplasty). The meta-analysis performed by Biccard and colleague analyses the effects of the two interventions
independently. The results support the
findings of other studies that suggest
that angioplasty in the lead up to
elective surgery may increase mortality
but also suggest that ‘CABG may
improve long term outcomes in vascular
surgical patients. The indications for
and timing of CABG in vascular surgical patients needs further research.’
Such a comment is a timely reminder
that one of the main purposes of
systematic reviews and meta-analyses is
to generate questions not answers.
To better understand the lack of an
obvious benefit from pre-operative
revascularisation it helps to review the
big picture. In the majority of patients
undergoing elective non-cardiac surgery cardiac ischaemia resulting in death
or prolongation of hospital stay is a
relatively uncommon post-operative
morbid event [3]. However, postoperative morbidity and mortality is
very commonly associated with preexisting cardiac failure manifest as exercise intolerance or poor functional
capacity. Studies have shown that
although there is some relationship
between the location of severe coronary
stenoses and the location of postoperative MIs, coronary thrombosis occurs
commonly at the site of milder stenoses
[4, 5]. Therefore, pre-emptive revascularisation may not fix the problem and
brings with it both delay and its own
risks including, in particular, the complexities of care surrounding anti-coagulant medication. Working from first
principles, it is not surprising that
angioplasty close to the time of surgery
is associated with a worse outcome than
CABG, as the anti-coagulant ‘tug of
war’ tends to favour the surgery and
therefore sets up the new stent for
‘elective thrombosis’. Many stents have
been deployed pre-operatively to open
up a lesion that was probably not going
to be the one to have caused a problem
which is, in itself, rare. So beware the
cardiology referral prompted by preoperative assessment that may expose
patients to the unnecessary risks associated with ‘stentomania’.
The increased use of Cardiopulmonary Exercise Testing (CPX) provides
an objective measure of fitness for
surgery. It has allowed many of us to
see clearly and understand better the
different risks to the patient undergoing
major non-cardiac surgery associated
with cardiac failure as a result of myocardial ischaemia, as distinct from myocardial ischaemia perse. As reported by
Older et al. [6] in one of his original
published series of patients undergoing
major intra-cavity surgery, a low Anaerobic Threshold with early ST segment
depression during a CPX test was
associated with a mortality rate of
42%, whereas patients without cardiac
failure and late ST segment changes in
exercise testing had no significant
increase in post-operative mortality
(4%) when compared to patients with
no ischaemic changes.
What can we take away from this
opportunity to reconsider the selection
of patients for referral for possible
coronary revascularisation prior to
non-cardiac, non-vascular surgery? If
you are currently guided by the ACC ⁄
AHA 2007 guidelines there is no need
to change your practice [1]. At my
institution, we have found that local
2009 The Authors
Journal compilation 2009 The Association of Anaesthetists of Great Britain and Ireland
guidelines agreed by surgeons, anaesthetists, intensivists and cardiologists can
further help to smooth the patient
pathway. Broadly, if pre-operative evaluation reveals possible coronary artery
disease then patients booked for elective.
Surgery should be referred to a
cardiologist as subsequent evaluation
and intervention may improve outcome
(if the criteria outlined in paragraph one
are met i.e. intervention would be
indicated in the absence of surgery). I
now warn patients that, if the cardiologist finds that they need extra treatments
to help their heart, their surgery may be
delayed by up to a year (i.e. the longer
interval suggested between placement
of a drug eluting stent and elective
surgery). The majority will be able to
have their elective surgery much earlier
than this and they are pleased. A tiny
minority that does end up with a
12-month postponement have hopefully had their expectations better
managed. Conversely, patients booked
for scheduled surgery for cancer, with a
very few exceptions (e.g. unstable
angina), are unlikely to benefit from
pre-operative revascularisation and, in
my opinion, surgery should not be
delayed. The discovery of possible coronary artery disease in these patients
should influence informed consent,
their peri-operative care pathway and
the members of the post-operative
multi-disciplinary team. Ideally, a cardiologist should agree pre-operatively to
be closely involved in the patient’s postoperative care.
M. Mythen
Smiths Medical Professor of
Anaesthesia and Critical Care,
Department of Health,
NIHR Comprehensive Biomedical
Research Centre, National Clinical
Lead, Enhanced Recovery Partnership
Programme, University College
London Hospitals,
London, UK
E-mail: m.mythen@ich.ucl.ac.uk
References
1 Fleisher LA, Beckman JA, Brown KA,
et al. ACC ⁄ AHA 2007 Guidelines on
Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery:
1049
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Anaesthesia, 2009, 64, pages 1045–1050
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Executive Summary: A Report of the
American College of Cardiology ⁄
American Heart Association Task
Force on Practice Guidelines (Writing
Committee to Revise the 2002
Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac
Surgery): Developed in Collaboration
With the American Society of Echocardiography, American Society of
Nuclear Cardiology, Heart Rhythm
Society, Society of Cardiovascular
Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine
and Biology, and Society for Vascular
Surgery. Circulation 2007; 116: 1971–
96.
1050
2 Biccard BM, Rodseth RN. A metaanalysis of the prospective randomised
trials of coronary revascularisation
before noncardiac vascular surgery
with attention to the type of coronary
revascularisation performed. Anaesthesia 2009; 161: 1105–1113.
3 Bennett-Guerrero E, Welsby I, Dunn
TJ, et al. The use of a postoperative
morbidity survey to evaluate patients
with prolonged hospitalization after
routine, moderate-risk, elective surgery. Anesthesia & Analgesia 1999; 89:
514–9.
4 Ellis GE, Hertzer NR, Young JR,
Brener S. Angiographic correlate
of cardiac death and myocardial
infarction complicating major
nonthoracic vascular surgery. The
American Journal of Cardiology 1996; 77:
1126–8.
5 Devereaux PJ, Goldman L, Cook DJ,
Gilbert K, Leslie K, Guyatt GH.
Perioperative cardiac events in patients
undergoing noncardiac surgery: a
review of the magnitude of the problem, the pathophysiology of the events
and methods to estimate and communicate risk. Canadian Medical
Association Journal 2005; 173: 627–
34.
6 Older P, Smith R, Courtney P, Hone
R. Preoperative evaluation of cardiac
failure and ischemia in elderly patients
by cardiopulmonary exercise testing.
Chest 1993; 104: 701–4.
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Journal compilation 2009 The Association of Anaesthetists of Great Britain and Ireland