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The measurement of adult blood pressure and management of hypertension before elective surgery: Joint Guidelines from the Association of Anaesthetists of Great Britain and Ireland and the British Hypertension Society

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This guideline aims to ensure that patients admitted to hospital for elective surgery are known to have blood pressures below 160 mmHg systolic and 100 mmHg diastolic in primary care. The objective for primary care is to fulfil this criterion before referral to secondary care for elective surgery. The objective for secondary care is to avoid spurious hypertensive measurements. Secondary care should not attempt to diagnose hypertension in patients who are normotensive in primary care. Patients who present to pre-operative assessment clinics without documented primary care blood pressures should proceed to elective surgery if clinic blood pressures are below 180 mmHg systolic and 110 mmHg diastolic.
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Guidelines
The measurement of adult blood pressure and management of
hypertension before elective surgery
Joint Guidelines from the Association of Anaesthetists of Great Britain and Ireland and the
British Hypertension Society
A. Hartle,
1
T. McCormack,
2
J. Carlisle,
3
S. Anderson,
4
A. Pichel,
5
N. Beckett,
6
T. Woodcock
7
and
A. Heagerty
8
1 Consultant, Departments of Anaesthesia and Intensive Care, St Marys Hospital, London, UK, and co-Chair,
Working Party on behalf of the AAGBI
2 General Practitioner, Whitby Group Practice, Spring Vale Medical Centre, Whitby, UK, Honorary Reader, Hull York
Medical School, UK, and co-Chair, Working Party, on behalf of the British Hypertension Society
3 Consultant, Departments of Anaesthesia, Peri-operative Medicine and Intensive Care, Torbay Hospital, Torquay, UK
4 Clinical Lecturer, Institute of Cardiovascular Sciences, University of Manchester, Manchester, UK and British
Hypertension Society
5 Consultant, Department of Anaesthesia, Manchester Royal Inrmary, Manchester, UK
6 Consultant, Department of Ageing and Health, Guysand St ThomasHospital, London, UK and British
Hypertension Society
7 Independent Consultant Anaesthetist, Hampshire, UK
8 Professor, Department of Medicine, University of Manchester, Manchester, UK, and British Hypertension Society
Summary
This guideline aims to ensure that patients admitted to hospital for elective surgery are known to have blood pressures
below 160 mmHg systolic and 100 mmHg diastolic in primary care. The objective for primary care is to full this crite-
rion before referral to secondary care for elective surgery. The objective for secondary care is to avoid spurious hyperten-
sive measurements. Secondary care should not attempt to diagnose hypertension in patients who are normotensive in
primary care. Patients who present to pre-operative assessment clinics without documented primary care blood pres-
sures should proceed to elective surgery if clinic blood pressures are below 180 mmHg systolic and 110 mmHg diastolic.
.................................................................................................................................................................
This is a consensus document produced by members of a Working Party established by the Association of Anaesthetists
of Great Britain and Ireland (AAGBI) and the British Hypertension Society (BHS). It has been seen and approved by
the AAGBI Board of Directors and the BHS Executive. It is licensed under a Creative Commons Attribution-NonCom-
mercial-NoDerivatives 4.0 International License. Date of review: 2020.
Accepted: 16 November 2015
.................................................................................................................................................................
Re-use of this article is permitted in accordance with the Creative Commons Deed, Attribution 2.5, which does not
permit commercial exploitation.
326 ©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and
distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
Anaesthesia 2016, 71, 326–337 doi:10.1111/anae.13348
Recommendations
General practitioners should refer patients for elec-
tive surgery with mean blood pressures in primary
care in the past 12 months less than 160 mmHg
systolic and less than 100 mmHg diastolic.
Secondary care should accept referrals that docu-
ment blood pressures below 160 mmHg systolic and
below 100 mmHg diastolic in the past 12 months.
Pre-operative assessment clinics need not measure
the blood pressure of patients being prepared for
elective surgery whose systolic and diastolic blood
pressures are documented below 160/100 mmHg in
the referral letter from primary care.
General practitioners should refer hypertensive
patients for elective surgery after the blood pressure
readings are less than 160 mmHg systolic and less
than 100 mmHg diastolic. Patients may be referred
for elective surgery if they remain hypertensive
despite optimal antihypertensive treatment or if
they decline antihypertensive treatment.
Surgeons should ask general practitioners to supply
primary care blood pressure readings from the last
12 months if they are undocumented in the referral
letter.
Pre-operative assessment staff should measure the
blood pressure of patients who attend clinic with-
out evidence of blood pressures less than
160 mmHg systolic and 100 mmHg diastolic being
documented by primary care in the preceding
12 months. (We detail the recommended method
for measuring non-invasive blood pressure accu-
rately, although the diagnosis of hypertension is
made in primary care.)
Elective surgery should proceed for patients who
attend the pre-operative assessment clinic without
documentation of normotension in primary care if
their blood pressure is less than 180 mmHg systolic
and 110 mmHg diastolic when measured in clinic.
The disparity between the blood pressure thresh-
olds for primary care (160/100 mmHg) and secondary
care (180/110 mmHg) allows for a number of factors.
Blood pressure reduction in primary care is based on
good evidence that the rates of cardiovascular morbid-
ity, in particular stroke, are reduced over years and
decades. There is no evidence that peri-operative blood
pressure reduction affects rates of cardiovascular events
beyond that expected in a month in primary care.
Blood pressure measurements might be more accurate
in primary care than secondary care, due to a less
stressful environment and a more practised technique.
What other guideline statements are available on
this topic?
There is detailed evidence-based guidance on the diag-
nosis and treatment of hypertension in the community
from, for example, the National Institute for Health
and Care Excellence [1]. There is little guidance on a
safeblood pressure for planned anaesthesia and sur-
gery.
Why was this guideline developed?
There is no national guideline for the measurement,
diagnosis or management of raised blood pressure
before planned surgery. There is little evidence that
raised pre-operative blood pressure affects postopera-
tive outcomes. Local guidelines vary from area to area.
Hypertension is a common reason to cancel or post-
pone surgery. In our sprint audit, 13% of elective
patients had further investigations precipitated by
blood pressure measurement, of whom half had their
surgery postponed. Across the UK this would equate
to ~100 concerned and inconvenienced patients each
day, with associated costs to the NHS and the national
economy [2, 3].
This guideline is the rst collaboration between
the AAGBI and the British Hypertension Society; these
two organisations have very different perspectives.
Members of the British Hypertension Society are con-
cerned with the long-term reduction in rates of cardio-
vascular disease, particularly strokes. Anaesthetists are
more focused on immediate complications, in the peri-
operative period. This guideline aims to prevent the
diagnosis of hypertension being the reason that
planned surgery is cancelled or delayed. As such, it
should also be of interest to hospital managers and
commissioners of hospital care.
How does this statement differ from existing
guidelines?
This guideline serves, therefore, not to advise on treat-
ment of hypertension, but rather to produce a com-
©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland. 327
Management of hypertension before elective surgery guidelines Anaesthesia 2016, 71, 326–337
mon terminology in diagnosis and referral, explaining
the impact of anaesthesia on blood pressure and vice
versa to the wider, non-anaesthetic community. At the
same time, it will review current best practice on the
measurement, diagnosis and treatment of hyperten-
sion.
Why does this statement differ from existing
guidelines?
Pre-operative blood pressure management involves
many specialties and professions: primary care, general
medicine, cardiology, endocrinology, pre-operative
assessment clinics and, of course, both anaesthetists
and surgeons. This list is not exhaustive. This guideline
should be a useful summary for all those clinicians
and for patients. The guidance takes into account not
just the best clinical evidence, but the particular pat-
tern of referral for treatment within the NHS in all
four countries of the UK.
Introduction
The National Institute for Health and Care Excellence
(NICE) has described hypertension as one of the most
important preventable causes of premature morbidity
and mortality in the UK[1]. The Association of
Anaesthetists of Great Britain and Ireland (AAGBI),
together with the British Hypertension Society, felt
there was a need for a nationally agreed policy state-
ment on how to deal with raised blood pressure in the
pre-operative period. We have based this statement on
a consensus view with the backing of graded evidence,
where such evidence is available.
Hypertension is almost always asymptomatic and
it is diagnosed following screening in general practice.
Managing hypertension pre-operatively is a complex
matter of balancing the risks of anaesthesia, treatment
and delay for the individual patient. Most cases of
hypertension are primary, i.e. with no other medical
cause. For the remainder, the cause for hypertension
may be associated with the reason for the proposed
operation.
Cancellations and postponements of planned sur-
gical procedures have been a major and long-standing
problem for healthcare worldwide. The quantiable
loss of resource is pitted against unquantiable and
signicant psychological, social and nancial implica-
tions of postponement for patients and their families.
Although guidelines exist for the treatment of ele-
vated blood pressure, there remains a paucity of liter-
ature and accepted guidelines for the peri-operative
evaluation and care of the patient with hypertension
who undergoes non-cardiac surgery [4]. Of particular
importance is dening the patients most vulnerable
to complications and the indications for immediate
and rapid antihypertensive treatment and/or post-
ponement of surgery to reduce these risks pre-opera-
tively, intra-operatively and postoperatively. Peri-
operative hypertension often occurs in conjunction
with sympathetic nociceptive stimulation during the
induction of anaesthesia, during surgery and with
acute pain in the early postoperative period. Hyper-
tension may also accompany hypothermia, hypoxia or
intravascular volume overload from excessive intra-
operative uid therapy, particularly in the ensuing
2448 h as uid is mobilised from the extravascular
space [46].
There are no nationally agreed guidelines for the
diagnosis or management of raised blood pressure
before elective surgery. The evidence regarding the
effect of raised pre-operative blood pressure is very
limited. Local guidelines do exist but vary from area to
area. Both the AAGBI and the British Hypertension
Society recognised the need for a national guideline
and consensus statement to address the various issues
of concern. We have limited our deliberations to a
specic scope. Only the period before planned surgery
is covered. Blood pressures which may cause an imme-
diate risk to health are specied, rather than those that
may cause risk over the long-term. The best method of
taking accurate blood pressure measurements is exam-
ined. We considered how long blood pressure should
be controlled before surgery is undertaken. Communi-
cation between different hospital departments, primary
care and the patient are of importance. We hope that
by providing national guidance the chances of a
patient receiving conicting advice will be minimised.
Scope
This guideline is aimed at adults presenting for
planned surgery. The following groups of patients are
specically not studied, although many of the general
points covered in the guideline may apply.
328 ©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland.
Anaesthesia 2016, 71, 326–337 Management of hypertension before elective surgery guidelines
Emergency/urgent surgery
By denition, these patients have no or very limited
time for investigation, treatment or postponement.
Such surgery must almost always proceed, but all those
involved, including the patient, must be aware of any
associated increased risk.
Obstetrics
Most cases of hypertension in pregnancy will be
directly related to the pregnancy (although with an
ageing obstetric population with higher rates of obe-
sity, this may be less so). The monitoring and treat-
ment of blood pressure is a specic and integral part
of obstetric care, regardless of the need for surgery,
and even for electiveCaesarean section there may be
very limited opportunity for delay.
Paediatrics
Childhood hypertension is relatively uncommon, and
its epidemiology and natural history is relatively
unclear and there are no denitive trials on screening.
Thus, its diagnosis and management, including pre-
operatively, is a specialist area beyond the scope of the
general guidance in this publication.
Cardiac surgery
Peri-operative hypertension commonly complicates
surgery for congenital and acquired cardiac disease.
Management will be affected by many other factors
including the planned procedure, the use or not of car-
diopulmonary bypass and the other indications for
vaso- and cardio-active medication. We have thus con-
sidered it to be a specialist area beyond the scope of
the general guidance in this publication.
Surgery for blood pressure management
This includes surgery for phaeochromocytoma and
bariatric surgery; we have excluded this from our guid-
ance for similar reasons to that of cardiac surgery.
Methods
We formed a Working Party consisting of four mem-
bers from each society who were academics and clini-
cians with varied interests, including vascular
anaesthesia, cardiology, elderly care medicine and gen-
eral practice. We agreed on the scope of the guideline,
and then carried out a systematic review with the qual-
ity of evidence described using the Grading of Recom-
mendations Assessment, Development and Evaluation
(GRADE) approach [7, 8]. The GRADE approach con-
siders the quality of a body of evidence as high, mod-
erate, low or very low. To achieve a full consensus
document was important. Therefore, we consulted 20
general practitioners, including those with a specialist
interest in cardiovascular medicine, as well as senior
academics. A consultation guideline was then made
available to members of both societies for comment.
We specically asked for and received comments from
the patient group, Blood Pressure UK. The comments
and responses have been made available online. The
Council and Executive of the respective societies were
given the task of nal approval.
Blood pressure, hypertension and
anaesthesia
The anaesthetist has two broad considerations in the
hypertensive patient who presents for surgery. One is
to be cognisant of the effect of chronic hypertension
on the individuals peri-operative and long-term car-
diovascular risk. The other is to consider whether the
blood pressure measured in the primary care setting is
associated with adverse peri-operative events and to
decide whether this should be reduced before surgery.
The association between hypertension and peri-
operative harm was rst reported in the 1950s [9, 10].
Systolic blood pressures in excess of 170 mmHg and
diastolic blood pressures in excess of 110 mmHg were
associated with complications such as myocardial
ischaemia [11]. Hypertension was the second-most
common factor associated with postoperative morbid-
ity [12]. In 2003, Weksler et al. published a quasi-
randomised controlled study of 989 treated hyperten-
sive patients who had diastolic blood pressures
between 110 and 130 mmHg measured in the anaes-
thetic room [13]. In one group, surgery proceeded
after intranasal nifedipine, and in the other group, sur-
gery was delayed while further antihypertensive treat-
ment was pursued in hospital. During the rst three
postoperative days, the rates of neurological and car-
diovascular complications were similar. One might
conclude that there was no difference in an infrequent
outcome, or that the study had insufcient power to
©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland. 329
Management of hypertension before elective surgery guidelines Anaesthesia 2016, 71, 326–337
detect a small difference (see section below, treatment
for hypertension: extension of evidence from the com-
munity to the peri-operative period).
The association of hypertension with cardiovascu-
lar disease is established, but there is no clear evidence
that patients with stage 1 or 2 hypertension (Table 1)
without evidence of target organ damage have
increased peri-operative cardiovascular risk [14].
Patients with stage 3 or 4 hypertension, who are more
likely to have target organ damage, have not been sub-
jected to rigorous randomised controlled trials of peri-
operative interventions. There is evidence that hyper-
tension with target organ damage is associated with a
small increased incidence of peri-operative major
adverse cardiovascular events [4]. It is not known
whether or not reducing blood pressure in these
patients during a postponement of planned surgery
would reduce this rate of events; there is sparse evi-
dence to guide a decision. Any decision should take
into account factors other than blood pressure, namely:
age; comorbidity; functional capacity (i.e. functional
status and reserve); and the urgency and indication for
surgery (see section below, The treatment of cardio-
vascular risk, not hypertension). The latest guidelines
published by the National Institute for Health and
Care Excellence (NICE), in conjunction with the Bri-
tish Hypertension Society, recognise the importance of
target organ damage in the management of hyperten-
sion by targeting a lower threshold for further medical
intervention [1]. Whether or not these thresholds and
targets should be rigorously applied in the peri-opera-
tive setting is not clear.
Patients with hypertension (controlled or uncon-
trolled) demonstrate a more labile haemodynamic pro-
le than their non-hypertensive counterparts [5]. The
induction of anaesthesia and airway instrumentation
can lead to a pronounced increase in sympathetic acti-
vation, which may lead to a signicant increase in
blood pressure and heart rate. A reduction in systemic
vascular resistance soon after the induction of anaes-
thesia commonly leads to varying degrees of hypoten-
sion. Reduction in vascular resistance is multifactorial
and may be secondary to loss of the baroreceptor
reex control, central neuraxial blockade, and direct
effects of anaesthetic agents. The effect on vascular
tone will be exaggerated by deepor excessive anaes-
thesia and in patients who are uid-depleted. This,
and the often exaggerated haemodynamic response to
surgery, pain and emergence from anaesthesia, have
also been described as being more common in the
hypertensive population [6]. Some researchers have
demonstrated an association between pre-operative
hypertension and relatively minor physiological
derangements such as intra-operative hypotension,
hypertension and arrhythmia, but studies have not
conclusively demonstrated that uctuations in haemo-
dynamic variables cause clinically signicant harm
[15]. Larger studies to investigate differences between
untreated hypertensive patients and those treated (suc-
cessfully and unsuccessfully) have not demonstrated
increased rates of peri-operative cardiovascular events.
However, these ndings may not be applicable to cur-
rent practice, as many of these studies were conducted
in the late 1970s [16].
This appreciation of labile haemodynamics in
hypertensive patients has led to a number of anaes-
thetic techniques designed to achieve a more stable
haemodynamic prole during surgery. These tech-
niques include co-induction, invasive arterial monitor-
ing with titrated or prophylactic vasopressor therapy,
depth-of-anaesthesia monitoring, beta-blockers and the
optimisation of stroke volume with intravascular uid
therapy. The omission of antihypertensive drugs, such
as angiotensin-converting enzyme inhibitors and
receptor blockers, combined with the careful re-
introduction of these drugs after surgery, is common-
place and appears to be associated with fewer signi-
cant peri-operative haemodynamic uctuations [17].
The introduction of peri-operative beta-blockade for
high cardiac-risk patients increases postoperative mor-
tality, secondary to hypotension and stroke, albeit with
less cardiac injury, as demonstrated in the POISE-1
study [18]. The anaesthetist should be aware that sud-
den withdrawal of certain antihypertensive agents such
Table 1 Categorisation of the stages of hypertension.
Category
Systolic blood
pressure; mmHg
Diastolic blood
pressure; mmHg
Stage 1 140159 9099
Stage 2 160179 100109
Stage 3 180209 110119
Stage 4 210 120
330 ©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland.
Anaesthesia 2016, 71, 326–337 Management of hypertension before elective surgery guidelines
as clonidine, alpha-methyldopa and beta-blockers can
be associated with adverse events. Withdrawal of
beta-blockers may also be associated with myocardial
ischaemia that is often silent in the peri-operative per-
iod and easily missed without continuous ECG moni-
toring and serial serum troponin measurements.
Best practice: the measurement of
blood pressure
Blood pressure should be measured in primary care
before non-urgent surgical referral (Fig. 1). Surgical
outpatients should arrange for primary care to sup-
ply blood pressure readings if these have not been
documented in the referral letter. Blood pressure
should be measured by pre-operative assessment
clinics in patients who attend the clinic without doc-
umented blood pressure readings from the last
12 months. The measurement should follow the
principles mandated for primary care (see below)
[1]. Blood pressures less than 180 mmHg systolic
and 110 mmHg diastolic in secondary care should
not preclude elective surgery, although the patient
Elective surgical referral appropriate
Mean
SBP < 160 mmHg
AND
DBP < 100 mmHg
in past year?
Refer
No Yes
Measure blood pressure up to
three times
Lowest SBP < 140 mmHg
AND the lowest DBP <
90 mmH
g
?
Refer
Yes
No
Lowest SBP < 160 mmHg
AND the lowest DBP <
100 mmH
g
?
Refer*
Yes
No
ABPM or HBPM
Mean ‘out of office’
SBP < 150 mmHg AND
the mean DBP < 95
mmHg?
Refer*
Yes
No
Refer*
Treat until ‘clinic’ SBP < 160 mmHg
AND DBP < 100 mmHg
Figure 1 Primary care blood pressure assessment of patients before referral for elective surgery. *Investigations and
treatment should continue to achieve blood pressures <140/90 mmHg. ABPM and HBPM, ambulatory and home
blood pressure measurement; DBP and SBP, diastolic and systolic blood pressure.
©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland. 331
Management of hypertension before elective surgery guidelines Anaesthesia 2016, 71, 326–337
should be asked to attend their general practice for
the concurrent determination of whether primary
care hypertension is present.
The setting in which blood pressure is measured
should be relaxed and temperate in a standardised
environment with current calibrated equipment. The
seated patient should have their supported arm out-
stretched for at least one minute before the initial
reading. The pulse rate and rhythm should be
recorded before the blood pressure is measured by a
validated device. Automated sphygmomanometers
(www.bhsoc.org/bp-monitors) are inaccurate when the
pulse is irregular, when the blood pressure should be
measured by auscultation over the brachial artery dur-
ing manual deation of an arm cuff.
Blood pressure should be measured in both arms
in patients scheduled for vascular or renal surgery. If
the difference between arms in systolic pressure is
greater than 20 mmHg, repeat the measurements; sub-
sequently, measure from the arm with the higher
blood pressure.
The patient is normotensive if the blood pressure
measurement is less than 140/90 mmHg. If the rst
measurement is equal to or higher than 140/
90 mmHg, the blood pressure should be measured
twice more, with each reading at least one minute
apart. The lower of the last two readings is recorded as
the blood pressure; if it is less than 140/90 mmHg the
patient is normotensive.
If the reading is between 140/90 mmHg and 179/
109 mmHg, the patient may have stage 1 or 2 hyper-
tension. In primary care, the patient would be offered
ambulatory (ABPM) or home blood pressure monitor-
ing (HBPM) to establish their true blood pressure
(GRADE 1B). If the reading is equal to or higher than
180/110 mmHg in primary care, the patient may have
severe hypertension and would be considered for
immediate treatment.
Best practice: the diagnosis of
hypertension
General practitioners should establish whether blood
pressure has been measured and managed in all adults
before non-urgent surgical referrals. A blood pressure
measurement taken within the preceding 12 months
should be detailed in the referral letter.
The diagnosis of hypertension in patients
referred for investigation of surgical disease that are
not treated for hypertension and who have not had
a blood pressure measurement in the preceding
12 months follows the same process as any other
primary care patient. We recommend that the prac-
tice instigates ambulatory or home blood pressure
measurements before non-urgent referrals if the stan-
dard blood pressure is equal to or greater than 160/
100 mmHg. If the patients ABPM/HBPM blood
pressure is equal to or greater than 150/95 mmHg
(or equal to or greater than 135/85 mmHg with tar-
get organ damage), the patient is diagnosed as hav-
ing hypertension; treatment should be discussed and
commenced using the NICE/BHS CG127 algorithm
[19]. This process can take place at the same time
as urgent surgical referral, but a reduction in blood
pressure to less than 160/100 mmHg should precede
non-urgent surgical referral. The referral letter
should document that an informed discussion has
taken place with patients who decline treatment, or
detail that all appropriate attempts have been made
to reduce blood pressure for patients with persistent
hypertension, which might have included specialist
investigations.
Surgical outpatients should request that general
practitioners forward primary care blood pressure
measurements if these have not been documented in
the referral letter. Pre-operative assessment clinics
should measure the blood pressures of patients who
present without documentation of primary care blood
pressures. If the blood pressure is raised above
180 mmHg systolic or 110 mmHg diastolic, the patient
should return to their general practice for primary care
assessment and management of their blood pressure,
as detailed above (Fig. 2). If the blood pressure is
above 140 mmHg systolic or 90 mmHg diastolic, but
below 180 mmHg systolic and below 110 mmHg dias-
tolic, the GP should be informed, but elective surgery
should not be postponed.
Best practice: the treatment of
hypertension
This section summarises the recommendations for pri-
mary care following the diagnosis of hypertension.
There is good evidence (GRADE 1A) for the treatment
332 ©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland.
Anaesthesia 2016, 71, 326–337 Management of hypertension before elective surgery guidelines
of hypertension with one or more of the following:
diuretics (thiazide, chlorthalidone and indapamide);
beta-blockers; calcium channel-blockers (CCB); angio-
tensin converting enzyme (ACE) inhibitors, or an
angiotensin-2 receptor blocker (ARB) [1]. In the
future, the threshold for treating high blood pressure
might change to cardiovascular risk (see below, the
treatment of cardiovascular risk, not hypertension).
Step 1 treatment
Patients aged less than 55 years should be offered an
ACE inhibitor, or a low-cost ARB. If an ACE inhi-
bitor is prescribed but is not tolerated (for example,
because of cough), offer a low-cost ARB. Angioten-
sin-converting enzyme inhibitors and ARBs are not
recommended in women of childbearing potential.
An ACE inhibitor should not be combined with
an ARB.
Patients aged over 55 years and Black patients of
African or Caribbean family origin of any age should
be offered a CCB. If a CCB is not suitable, for example
because of oedema or intolerance, or if there is evi-
dence of heart failure or a high risk of heart failure, a
thiazide-like diuretic should be offered.
If diuretic treatment is to be initiated or changed,
offer a thiazide-like diuretic, such as chlorthalidone
(12.525.0 mg once daily), or indapamide (1.5 mg
modied-release once daily or 2.5 mg once daily), in
preference to a conventional thiazide diuretic such as
bendroumethiazide or hydrochlorothiazide.
For patients who are already having treatment
with bendroumethiazide or hydrochlorothiazide
Lowest SBP < 180 mmHg
AND the lowest DBP <
110 mmH
g
?
Surgeon receives referral
Lowest SBP < 160 mmHg
AND the lowest DBP <
100 mmH
g
?
Yes Proceed
No
Documented
SBP < 160 mmHg
AND
DBP < 100 mmHg
in past year?
Proceed
Yes
No
Request measurements from GP
Refer back to GP*
Yes Proceed*
No
Measure blood pressure up to
three times
Figure 2 Secondary care blood pressure assessment of patients after referral for elective surgery. *The GP should be
informed of blood pressure readings in excess of 140 mmHg systolic or 90 mmHg diastolic, so that the diagnosis of
hypertension can be refuted or conrmed and investigated and treated as necessary. DBP and SBP, diastolic and sys-
tolic blood pressure.
©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland. 333
Management of hypertension before elective surgery guidelines Anaesthesia 2016, 71, 326–337
and whose blood pressure is stable and well con-
trolled, treatment with the bendroumethiazide or
hydrochlorothiazide should be continued.
Beta-blockers are not a preferred initial therapy
for hypertension. However, beta-blockers may be
considered in younger patients, particularly those
with an intolerance or contraindication to ACE inhi-
bitors and ARBs, or women of childbearing potential
or patients with evidence of increased sympathetic
drive. If beta-blockers are started and a second drug
is required, add a CCB rather than a thiazide-like
diuretic to reduce the persons risk of developing
diabetes.
Step 2 treatment
If blood pressure is not controlled by Step 1 treatment,
use a CCB in combination with either an ACE inhibi-
tor or an ARB.
If a CCB is not suitable for Step 2 treatment, for
example because of oedema or intolerance, or if there
is evidence of heart failure or a high risk of heart fail-
ure, offer a thiazide-like diuretic.
For Black patients of African or Caribbean family
origin, consider an ARB in preference to an ACE inhi-
bitor, in combination with a CCB.
Step 3 treatment
Before considering Step 3 treatment, check that drugs
from Step 2 have been prescribed at optimal doses, or
at the maximum tolerated doses. If treatment with
three drugs is required, the combination of ACE inhi-
bitor or ARB, CCB and thiazide-like diuretic should be
used.
Step 4 treatment
If resistant blood pressure exceeds 140/90 mmHg in
clinic after treatment with the optimal or highest-toler-
ated doses of an ACE inhibitor, or an ARB plus a
CCB, with a diuretic; adding a fourth antihypertensive
drug and expert advice should be considered.
Further diuretic therapy with low-dose spironolac-
tone (25 mg once daily) should be considered if the
serum potassium concentration <4.6 mmol.l
1
. Cau-
tion is required in patients with reduced estimated
glomerular ltration rates because of an increased risk
of hyperkalaemia. Increasing the dose of thiazide-like
diuretics should be considered if the serum potassium
concentration >4.5 mmol.l
1
.
Serum sodium and potassium concentrations and
renal function should be checked within 1 month of
increasing diuretic dose, and repeated as required
thereafter. If further diuretic therapy for resistant
hypertension at Step 4 is not tolerated, or is con-
traindicated or ineffective, consider an alpha-blocker
or beta-blocker. If blood pressure remains uncontrolled
with the optimal or maximum tolerated doses of four
drugs, expert advice should be sought if it has not yet
been obtained.
As recently as 2008, the HYVET study demon-
strated the clinical benets of treating hypertension in
people aged 80 years, while health economic analysis
has conrmed the cost effectiveness of this strategy [1,
20]. As a result, NICE now recommends that patients
aged 80 years should be offered treatment only if
they have stage 2 hypertension. The 2011 Hyperten-
sion Guideline also recommends that the decision to
treat should be based on standing blood pressure, and
should take into account the presence of co-morbid-
ities such as dementia. The guideline also makes a dis-
tinction between initiating treatment in the over-80s
and continuing long-term and well-tolerated treatment
when patients reach this age. In other words, patients
who were started on treatment when younger should
not have their current therapy back-titrated when they
celebrate their 80th birthday.
The treatment of cardiovascular risk,
not hypertension
It is likely that treatment for hypertension will no
longer be based upon blood pressure [21]. This is a
surprising statement; the diagnosis of hypertension
that merits treatment has until recently been based
on patientsblood pressure, irrespective of other car-
diovascular risk factors, despite the NICE guidance
recognising their importance [1]. This practice con-
icts with the treatment of hypercholesterolaemia,
which is not based on the cholesterol concentration
alone, but instead on the composite 5- or 10-year risk
of: stroke; myocardial infarction; heart failure; cardio-
vascular morbidity; or death, ascribed to these diag-
noses. The magnitude by which cardiovascular disease
is reduced by treatment for both hypercholesterolaemia
334 ©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland.
Anaesthesia 2016, 71, 326–337 Management of hypertension before elective surgery guidelines
and hypertension is dependent on the composite car-
diovascular risk, not the concentration of cholesterol
or the blood pressure. Anaesthetists should gauge their
concern for a hypertensive patient by the calculated
ve-year rate of cardiovascular events, not by the
blood pressure measurement per se.
Hypertension is common; this is responsible for
the well-publicised reduction in population rates of
stroke by antihypertensive treatment. The absolute
effect of treatment for the individual, even over a ve-
year period, is smaller than many anaesthetists might
realise. Table 2 presents the effect of ve-year antihy-
pertensive treatment for cardiovascular risk in a popu-
lation quartered by the ve-year rate of any
cardiovascular event. Planned major surgery temporar-
ily increases mortality. For instance, planned open
repair of abdominal aortic aneurysm increases mortal-
ity in the rst postoperative month ten times, whereas
endovascular repair increases mortality four times. If
cardiovascular events are similarly increased by major
planned surgery, one would anticipate that the pre-
operative antihypertensive treatment of cardiovascular
risk would have a proportionately greater absolute
effect on the rates of events while their risk remains
elevated. Table 3 illustrates the absolute effect of estab-
lished antihypertensive treatment in the month follow-
ing a planned operation in patients from Table 2,
assuming two scenarios: that the operation does not
affect the rates of cardiovascular events; and that the
operation increases the rates of cardiovascular events
six times.
This guideline has outlined that blood pressure
before planned non-urgent surgery is measured in pri-
mary care, where the diagnosis of hypertension is
Table 2 The effect of antihypertensive treatment on the ve-year rates of events (per 1000) in a population quar-
tered on the basis of the untreated cardiovascular ve-year risk: lowest quartile (<11% risk); next quartile (1115%
risk); next quartile (1521% risk); highest quartile (>21% risk).
Quartile of risk
Any event Stroke CHD Heart failure
No
treatment Treatment No treatment Treatment No treatment Treatment No treatment Treatment
Highest quartile
Event rates 270/1000 232/1000 70/1000 58/1000 63/1000 53/1000 47/1000 34/1000
Event reduction 38/1000 12/1000 10/1000 13/1000
Second quartile
Event rates 180/1000 156/1000 49/1000 40/1000 42/1000 36/1000 27/1000 23/1000
Event reduction 24/1000 9/1000 6/1000 4/1000
Third quartile
Event rates 120/1000 100/1000 36/1000 29/1000 33/1000 28/1000 15/1000 13/1000
Event reduction 20/1000 7/1000 5/1000 2/1000
Lowest quartile
Event rates 60/1000 46/1000 17/1000 11/1000 17/1000 14/1000 6/1000 5/1000
Event reduction 14/1000 6/1000 3/1000 1/1000
CHD, coronary heart disease.
Table 3 The absolute reduction in event rates per 1000 patients per month by antihypertensive treatment, assuming
that the control rate is unaffected by surgery (same) or increased, in this example sixfold (96).
Quartile of risk
Any event Stroke CHD Heart failure
Same 36 Same 36 Same 36 Same 36
Highest quartile 0.6 3.8 0.2 1.2 0.2 1 0.2 1.3
Next quartile 0.4 2.4 0.2 0.9* 0.1 0.6 0.1 0.4
Next quartile 0.3 1.8 0.1 0.7 0.1 0.6 0.0 0.2
Lowest quartile 0.2 1.2 0.1 0.6 0.1 0.3 0.0 0.1
*The 0.2was rounded up from a value near 0.15, which is why this value 96 is 0.9, not 1.2.
CHD, coronary heart disease.
©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland. 335
Management of hypertension before elective surgery guidelines Anaesthesia 2016, 71, 326–337
made, and treatment is managed. The lifelong risk of
mortality and morbidity may be unaffected by post-
poning surgery for the assessment of cardiovascular
risk by primary care and possible antihypertensive
treatment [22]. For instance, clinicians might like to
consider the uncertainty in how long it takes for car-
diovascular risk to fall with antihypertensive medica-
tion (as opposed to how long it takes for blood
pressure to fall), and the 1% relative increase in car-
diovascular risk that accompanies each postponed
month, due to the patient ageing. Clinicians might also
consider that patients who smoke or who have hyperc-
holesterolaemia are not subjected to the summary can-
cellations justied by blood pressure readings. A
further consideration is the absence of a scale of
enthusiasm for postponing surgery that matches the
continuum of cardiovascular risk, which would result
in older smoking hypercholesterolaemic normotensive
men having surgery postponed more frequently than
younger hypertensive women who do not have any
other cardiovascular risk factors.
Communication
Pre-operative assessment clinics should inform general
practitioners when they measure raised blood pressures
in patients who have not had readings taken in pri-
mary care in the preceding 12 months. The letter
should request that the general practitioner determine
whether the patient has hypertension in primary care.
The letter should also state whether or not surgery will
proceed without a diagnosis of hypertension being
made or treatment commenced.
Appendix 1 is an example of a letter explaining
that surgery will not proceed until the diagnosis of
hypertension has been excluded or conrmed, and in
the latter case treated with the patients consent. It is
important that the patient has a copy and is instructed
to make an appointment at their surgery with a nurse
or a doctor and to take the letter with them. The lan-
guage used should seek cooperative management
rather than demand action. In the rst instance, the
GP will need to establish that the blood pressure is
high and this is not a white coat effect. It must be
clearly stated how to re-establish the procedural path-
way when the blood pressure has been shown to be
satisfactory, treated or not.
References
1. National Institute for Health and Care Excellence. Hyperten-
sion: Clinical management of primary hypertension in adults.
2011 NICE Clinical Guideline CG127. http://www.nice.org.uk/
guidance/cg127 (accessed 15/01/2015).
2. Cook TM, Woodall N, Frerk C. Fourth National Audit Project.
Major complications of airway management in the UK: results
of the Fourth National Audit Project of the Royal College of
Anaesthetists and the Difficult Airway Society. Part 1: anaes-
thesia. British Journal of Anaesthesia 2011; 106: 61731.
3. Cook TM, Andrade J, Bogod DG, et al. The 5th National Audit
Project (NAP5) on accidental awareness during general anaes-
thesia: patient experiences, human factors, sedation, consent
and medicolegal issues. Anaesthesia 2014; 69: 110216.
4. Howell SJ, Sear JW, Foex P. Hypertension, hypertensive heart
disease and perioperative cardiac risk. British Journal of
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5. Longnecker DE. Alpine anesthesia: can pretreatment with
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6. Prys-Roberts C, Greene LT, Meloche R, Foex P. Studies of
anaesthesia in relation to hypertension II. Haemodynamic
consequences of induction and endotracheal intubation.
British Journal of Anaesthesia 1971; 43: 53147.
7. Guyatt GH, Oxman AD, Kunz R, et al. Going from evidence to
recommendations. British Medical Journal 2008; 336: 1049
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8. Guyatt GH, Oxman AD, Vist G, et al. for the GRADE Working
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evidence and strength of recommendations. British Medical
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9. Smithwick RH, Thompson JE. Splanchnicectomy for essential
hypertension; results in 1,266 cases. Journal of the American
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10. Thompson JE, Smithwick RH. Surgical measures in hyperten-
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13. Weksler N, Klein M, Szendro G, et al. The dilemma of imme-
diate preoperative hypertension: to treat and operate, or to
postpone surgery? Journal of Clinical Anesthesia 2003; 15:
17983.
14. Hanada S, Kawakami H, Goto T, et al. Hypertension and anes-
thesia. Current Opinion in Anaesthesiology 2006; 19: 3159.
15. Chung F, Mezei G, Tong D. Pre-existing medical conditions as
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16. Goldman L, Caldera DL. Risks of general anesthesia and elec-
tive operation in the hypertensive patient. Anesthesiology
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17. Comfere T, Sprung J, Kumar MM, et al. Angiotensin system
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Anaesthesia 2016, 71, 326–337 Management of hypertension before elective surgery guidelines
19. Hypertension Pathyways. http://pathways.nice.org.uk/pathways/
hypertension#path=view%3A/pathways/hypertension/diagnosis-
and-assessment-of-hypertension.xml&content=view-index (ac-
cessed 16/01/2015).
20. Beckett NS, Peters R, Fletcher AE, et al. Treatment of hyper-
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Appendix 1
Example of letter to general practitioner from pre-assessment clinic following measurement of raised blood pres-
sure in patients who have not had readings taken in primary care in the preceding 12 months.
Dear Doctor
Unfortunately, the procedure for Mr/Ms ...................... has been postponed because their blood pressure was
found to be 182/114 in their pre-operative assessment. It was measured several times following the AAGBI/BHS guide-
lines. The guidelines suggest a blood pressure level higher than 180/110 is unsuitable for elective anaesthesia.
We have asked the patient to make an appointment at their surgery for further assessment of their blood pressure. We
would be grateful if you could verify that this is the true blood pressure level and not a white coat effect and treat appro-
priately if the patient has hypertension.
We will be pleased to accept the patient back for surgery if their clinical blood pressure is below 160/100. Please
ask the patient to contact ........................... and inform us of their current blood pressure and what medica-
tion, if any, was required to achieve this.
Many thanks in anticipation of your help with this matter
The following GPs were consulted about this letter:
Dr Chris Arden, Dr Ivan Benett, Dr Mark Davis, Dr Richard Falk, Prof David Fitzmaurice, Prof Ahmet Fuat, Dr
Napa Gopi, Dr Kathryn Grifth, Dr Rosie Heath, Prof Richard Hobbs, Dr Paul Johnson Prof Richard McManus, Dr
Jonathan Morrell, Dr Washik Parkar, Dr Neil Paul, Dr Jon Pittard, Dr Peter Savill, Dr Jonathan Shribman, Dr Harjit
Singh, Dr Heather Wetherell.
Management of hypertension before elective surgery guidelines Anaesthesia 2016, 71, 326–337
©2016 The Authors. Anaesthesia published by John Wiley &Sons Ltd on behalf of Association of Anaesthetists of Great Britain and Ireland. 337
... Managing hypertension pre-operatively is a matter of balancing the risks of anesthesia, treatment and delay for the individual patient [2]. Cancellations and postponements of elective surgical procedures on the ground of high arterial blood pressure (particularly on arrival in the operating theater) have been a major and long-standing problem for every healthcare workers and the patients around in low-income countries [6e8]. ...
... The first is recognizing the effect of chronic hypertension on the individual's peri-operative and long-term cardiovascular risk. The second is consider the blood pressure measured in the pre-operative period is associated with adverse peri-operative events and to decide whether this should be reduced before surgery [2]. ...
... The relationship between hypertension and perioperative complications was first reported in the 1950s and myocardial ischemia was associated with a raised systolic blood pressures above 180 mmHg and diastolic blood pressures in excess of 110 mmHg [2]. On the other hand, well treated and controlled preoperative hypertension not seem to be an important risk factor of intraoperative and/or postoperative myocardial ischemia [9,10]. ...
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High blood pressure Perioperative management of hypertension Anesthesia or surgery and hypertension a b s t r a c t Hypertension is a major clinical challenge and public health problem. The number of surgical cases with pre-existing hypertension is dramatically increased and the most common medical reason for deferring surgery. Although there is little evidence, chronic or newly diagnosed elevated blood pressure is a risk factor for perioperative cardiovascular and cerebrovascular events. Evidences on perioperative optimization , which patients should be postponed and for how long, and management strategies for reducing cancellation are limited, particularly in low-income countries such as Ethiopia. These guidelines provide a strategy to manage and reduce cancelation of surgery in patients with chronic or newly diagnosed hypertension. Senior anaesthetist', with input from department of internal medicine and surgery, were responsible to develop this clinical guideline to promote best evidence-based, effective, affordable, and safer perioperative management of adult patients with pre-existing or newly diagnosed hypertension scheduled for elective surgical procedures. As part of the guideline development process, a systematic review of studies published in peer-review journals was employed on varies aspects related to treatment, assessment and risk stratification, and reduction strategies for postponing surgery in patients with elevated blood pressure. After a comprehensive searching of electronic sources and a review of the evidence, the authors (working as senior anaesthetist and researcher) formulated recommendations that addressed various aspects of perioperative optimization of hypertensive patients, considering setups with limited recourse. We found that defer surgery on the ground of elevated blood pressure in patients with stage 1 or 2 hypertension is not necessary. Although we identified numerous gaps between studies, we recommend that delay surgery in patients with stage 3 hypertension, who do not have high car-diovascular risk, is not necessary.
... Whilst there is little evidence supporting the delay of elective surgery for class I or II hypertension patients 47,52 , the extremes of blood pressure are predictive of poorer postsurgical outcomes 47 . In a multi-disciplinary setting, patients being considered for bariatric surgery can be assessed by a bariatric physician who can initiate or optimise treatment as well as assess for cardiovascular risk factors. ...
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Modifiable risk factors such as diabetes, hyperlipidaemia, hypertension, obstructive sleep apnoea (OSA), chronic kidney disease (CKD), chronic steroid use and smoking, have been shown in observational studies to negatively affect surgical outcomes. The purpose of this study is to identify and determine the effect of modifiable risk factors on post‐operative bariatric surgery leak, as pre‐operative risk modification has been shown to reduce the impact on complications. Electronic literature searches of MEDLINE, PUBMED, OVID and Cochrane Library databases were performed, including a manual reference check, over the period of 2010 and 2020. 620 articles were screened according to the PRISMA protocol. Twenty articles were included in the meta‐analysis of risk factors. Significant risk factors and the associated effect sizes include: 1. smoking with an overall OR of 1.31 [1.06, 1.61] and an OR of 1.72 [1.44, 2.05] in sleeve gastrectomy patient cohorts; 2. diabetes with an overall OR of 1.23 [1.08, 1.39] and an OR of 1.33 [1.02, 1.73] in Roux‐en‐Y patient cohorts; 3. CKD with an overall OR of 2.41 [1.62, 3.59] and 4. steroid use with an overall OR of 1.57 [1.22, 2.02].Non‐significant risk factors include hypertension with an OR of 0.85, 1.83, OSA with an OR of 1.08 [0.83, 1.39] and hyperlipidaemia with an OR of 0.80 [0.61, 1.04]. Combined sleeve gastrectomy and Roux‐en‐Y patient cohorts with hyperlipidaemia have shown a protective effect of 0.78 [0.65, 0.94]. Significant risk factors for leak post bariatric surgery are smoking in all patients and particularly sleeve gastrectomy patients, diabetes for all patients and particularly Roux‐en‐Y patients, and CKD and chronic steroid for all patients. Hyperlipidaemia in two combined patient cohorts (sleeve gastrectomy and Roux‐en‐Y) appears to have a weak protective effect. This article is protected by copyright. All rights reserved.
... Even though there are several international reference guidelines that account for the importance of management of perioperative BP [6][7][8], at present there are no universally accepted preoperative BP thresholds, as BP targets need to consider patient baseline BP, surgery type, and risk of short-term complications [9]. Furthermore, there is a clear gap in the knowledge of short-and long-term implications of acute hypo-and hypertensive perioperative episodes. ...
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Study objective Our goal is to review the outcomes of acute hypertensive/hypotensive episodes from articles published in the past 10 years that assessed the short- and long-term impact of acute hypertensive/hypotensive episodes in the perioperative setting. Methods We conducted a systematic peer review based upon PROSPERO and Cochrane Handbook protocols. The following study characteristics were collected: study type, author, year, population, sample size, their definition of acute hypertension, hypotension or other measures, and outcomes (probabilities, odds ratio, hazard ratio, and relative risk) and the p-values; and they were classified according to the type of surgery (cardiac and non-cardiac). Results A total of 3,680 articles were identified, and 66 articles fulfilled the criteria for data extraction. For the perioperative setting, the number of articles varies by outcome: 20 mortality, 16 renal outcomes, 6 stroke, 7 delirium and 34 other outcomes. Hypotension was reported to be associated with mortality (OR 1.02–20.826) as well as changes from the patient’s baseline blood pressure (BP) (OR 1.02–1.36); hypotension also had a role in the development of acute kidney injury (AKI) (OR 1.03–14.11). Postsurgical delirium was found in relation with BP lability (OR 1.018–1.038) and intra- and postsurgical hypotension (OR 1.05–1.22), and hypertension (OR 1.44–2.34). Increased OR (37.67) of intracranial hemorrhage was associated to postsurgical systolic BP >130 mmHg. There was a wide range of additional diverse outcomes related to hypo-, hypertension and BP lability. Conclusions The perioperative management of BP influences short- and long-term effects of surgical procedures in cardiac and non-cardiac interventions; these findings support the burden of BP fluctuations in this setting.
... Why is an optimal pre-anesthesia blood pressure important? Preoperative hypertension can cause perioperative hemodynamic changes associated with perioperative morbidity and mortality, such as intraoperative hypotension and tachycardia [24,25]. It has been claimed that hypertensive patients may have greater cardiovascular lability and exaggerated hemodynamic stress response, particularly at the induction of anesthesia, due to increased catecholamine levels and increased sensitivity of peripheral vessels to catecholamines [26]. ...
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Background: Blood pressure fluctuations appear more significant in patients with poorly controlled hypertension and are known to be associated with adverse perioperative morbidity. In the present study, we aimed to determine the effects of antihypertensive drug treatment strategies on preanesthetic operating room blood pressure measurements. Methods: A total of 717 patients participated in our study; 383 patients who were normotensive based on baseline measurements and not under antihypertensive therapy were excluded from the analysis. The remaining 334 patients were divided into six groups according to the antihypertensive drug treatment. These six groups were examined in terms of preoperative baseline and pre-anesthesia blood pressure measurements. Results: As a result of the study, it was observed that 24% of patients had high blood pressure precluding surgery, and patients using renin-angiotensin-aldosterone system inhibitors (RAASI) had higher pre-anesthesia systolic blood pressure than patients using other antihypertensive drugs. Patients who received beta-blockers were also observed to have the lowest pre-anesthesia systolic blood pressure, diastolic blood pressure, and mean blood pressure, compared to others. Conclusions: Recently, whether RAASI should be continued preoperatively remains controversial. Our study shows that RAASI cannot provide optimal pre-anesthesia blood pressure and lead to an increase in the number of postponed surgeries, probably due to withdrawal of medication before the operation. Therefore, the preoperative discontinuation of RAASI should be reevaluated in future studies.
Chapter
The decision to withhold or continue perioperative angiotensin-converting enzyme inhibitors (ACE-Is)/angiotensin receptor blockers (ARBs) before noncardiac surgery remains an ongoing clinical dilemma. Current guidelines are conflicting and based on small meta-analyses, small randomized controlled trials, and observational data only. The current body of evidence demonstrates a clear signal that ACE-I/ARB treatment continuation on the morning of surgery is associated with increased risk for intraoperative hypotension. Additionally, the accumulated time spent below a threshold mean arterial pressure (MAP) of 65 mm Hg intraoperatively is associated with increasing cardiac and renal morbidity. Nevertheless, the association between ACE-I/ARB–induced hypotension and adverse outcomes has not been made. Withholding versus continuing therapy on the day before surgery is associated with similar preoperative blood pressures, thus alleviating fears of preoperative hypertension associated with therapy omission. Increased mortality outcomes in the postoperative period have been linked to treatment nonresumption after noncardiac surgery, and therapy should be restarted as soon as clinically feasible. An individualized approach dependent on patient comorbidities, reason for therapy initiation, concomitant antihypertensive therapy, and specific anesthesia type (neuraxial versus general, versus combined) is recommended. Further evidence based on large randomized controlled trials are required.
Effective preoperative evaluation of patients prior to major vascular surgery remains a significant multidisciplinary challenge. Focused preoperative evaluation targeted to organ systems can mitigate the combined effects of inherently high-risk surgical procedures undertaken in a patient population with well-recognized comorbidity. Careful history and examination, supported by appropriate investigations and specialist input, remains the cornerstone of this process, with risk increasingly quantified by dedicated scoring systems. In addition, the objective assessment of functional capacity is now common in UK units with CPET testing widely employed and considered a ‘gold standard’ by many. When employed in a timely manner, complete preoperative assessment allows more informed perioperative decision-making, frank discussion of risk with the patient and effective utilization of critical care resources if required.
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Diabetic and hypertensive patients are at increased risk of vascular complications. Carotid Doppler ultrasonography serves as a non-invasive gold standard technique/tool to access and monitor carotids hemodynamics and morphology. There is a need to predict difference in carotid artery hemodynamics among hypertensive and diabetic patients.Aim: Aim of this study is to find out the hemodynamics of carotid artery in diabetic and hypertensive patients. Method: Cross sectional study conducted at University Ultrasound Clinic Green Town. All patients were investigated with Toshiba Xario XG with 5-7.5MHz linear probe. Study included diabetic and hypertensive individuals, whereas patients with history of carotid endarterectomy, carotid stenting and co-morbidity were excluded. Total 200 participants were recruited, 41 were diabetic and hypertensive, while 159 were normal subjects. Statistical analysis was performed using SPSS version 21. Results: From 200 participants were recruited, out of them 41 patients with 20.5% were positive with diabetes and hypertension and 159 patients with 79.5% were negative with diabetes and hypertension. Right common carotid artery intima media thickness (IMT) mean ± S.D was 0.659±0.114mm with p-value (0.022). Left common carotid end diastolic velocity mean ± S.D was 16.719±6.303cm/s with p-value (0.002). Conclusion: The study highlighted that common carotid artery intima media thickness (IMT) and common carotid artery end diastolic velocity were significantly correlated with hypertension and diabetes. Our findings revealed that common carotid artery IMT and EDV were significant in hypertensive and diabetic patients. Indeed, hypertension and diabetes are mainly associated with vascular complications.
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The 5th National Audit Project of the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland into accidental awareness during general anaesthesia yielded data related to psychological aspects from the patient, and the anaesthetist, perspectives; patients' experiences ranged from isolated auditory or tactile sensations to complete awareness. A striking finding was that 75% of experiences were for < 5 min, yet 51% of patients (95% CI 43-60%) experienced distress and 41% (95% CI 33-50%) suffered longer-term adverse effect. Distress and longer-term harm occurred across the full range of experiences but were particularly likely when the patient experienced paralysis (with or without pain). The patient's interpretation of what is happening at the time of the awareness seemed central to later impact; explanation and reassurance during suspected accidental awareness during general anaesthesia or at the time of report seemed beneficial. Quality of care before the event was judged good in 26%, poor in 39% and mixed in 31%. Three quarters of cases of accidental awareness during general anaesthesia (75%) were judged preventable. In 12% of cases of accidental awareness during general anaesthesia, care was judged good and the episode not preventable. The contributory and human factors in the genesis of the majority of cases of accidental awareness during general anaesthesia included medication, patient and education/training. The findings have implications for national guidance, institutional organisation and individual practice. The incidence of 'accidental awareness' during sedation (~1:15 000) was similar to that during general anaesthesia (~1:19 000). The project raises significant issues about information giving and consent for both sedation and anaesthesia. We propose a novel approach to describing sedation from the patient's perspective which could be used in communication and consent. Eight (6%) of the patients had resorted to legal action (12, 11%, to formal complaint) at the time of reporting. The 5th National Audit Project methodology provides a standardised template that might usefully inform the investigation of claims or serious incidents related to accidental awareness during general anaesthesia.
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Background: We aimed to investigate whether the benefits of blood pressure-lowering drugs are proportional to baseline cardiovascular risk, to establish whether absolute risk could be used to inform treatment decisions for blood pressure-lowering therapy, as is recommended for lipid-lowering therapy. Methods: This meta-analysis included individual participant data from trials that randomly assigned patients to either blood pressure-lowering drugs or placebo, or to more intensive or less intensive blood pressure-lowering regimens. The primary outcome was total major cardiovascular events, consisting of stroke, heart attack, heart failure, or cardiovascular death. Participants were separated into four categories of baseline 5-year major cardiovascular risk using a risk prediction equation developed from the placebo groups of the included trials (<11%, 11-15%, 15-21%, >21%). Findings: 11 trials and 26 randomised groups met the inclusion criteria, and included 67,475 individuals, of whom 51,917 had available data for the calculation of the risk equations. 4167 (8%) had a cardiovascular event during a median of 4·0 years (IQR 3·4-4·4) of follow-up. The mean estimated baseline levels of 5-year cardiovascular risk for each of the four risk groups were 6·0% (SD 2·0), 12·1% (1·5), 17·7% (1·7), and 26·8% (5·4). In each consecutive higher risk group, blood pressure-lowering treatment reduced the risk of cardiovascular events relatively by 18% (95% CI 7-27), 15% (4-25), 13% (2-22), and 15% (5-24), respectively (p=0·30 for trend). However, in absolute terms, treating 1000 patients in each group with blood pressure-lowering treatment for 5 years would prevent 14 (95% CI 8-21), 20 (8-31), 24 (8-40), and 38 (16-61) cardiovascular events, respectively (p=0·04 for trend). Interpretation: Lowering blood pressure provides similar relative protection at all levels of baseline cardiovascular risk, but progressively greater absolute risk reductions as baseline risk increases. These results support the use of predicted baseline cardiovascular disease risk equations to inform blood pressure-lowering treatment decisions. Funding: None.
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Hypertensive cardiovascular disease remains one of the foremost problems facing medicine today. It has been estimated that one-fourth of the adult population of this country has high blood pressure1 and that the complications of this condition account for more deaths annually than does cancer. Hypertension is of particular importance because it is responsible for many deaths and much premature disability in young and middle-aged persons. It is highly desirable, therefore, to lower the mortality for such a disease. Many forms of therapy have been used in an effort to control hypertension. The principal ones may be classified under three headings: (1) diets low in sodium and fat, (2) drugs with a hypotensive or sedative effect, and (3) surgery. The form of surgical therapy that has been used most extensively is intervention on the sympathetic nervous system. There are many data in the literature concerning the short-term effects of various
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