This document discusses hypertension, including its definition, prevalence, classification, etiology, consequences, pathophysiology, and perioperative and long-term management. Some key points include: - Hypertension is defined as blood pressure ≥140/90 mmHg. About 970 million people worldwide have high blood pressure. - Perioperatively, hypertension can occur during induction of anesthesia or post-operatively due to discontinuation of antihypertensive medications. It increases the risk of postoperative complications. - Long-term treatment involves lifestyle modifications like reducing sodium intake and exercise, as well as pharmacological therapy using medications like thiazide diuretics, calcium channel blockers, ACE inhibitors, and ARBs to

1. A DISCUSSION
Kristel R. Quintas-Quitaleg, MD
Pangasinan Provincial Hospital
August 22, 2017
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2. INTRODUCTIO
N
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Hypertension: elevated
BP, (≥140/90 mmHg)
Important:
• Must be based on the average of
≥2 stable readings of arterial
pressure, taken at ≥2 visits after
initial screening
• Not on a single isolated recording
About 970M people
worldwide have high BP.
• Estimated cases in 2025:
1.56B adults.
• Prevalence of undiagnosed
HTN: 1 in 15
BP values increase with age:
• <45 y/o: males > females
• ≥65 y/o: females > males
• 90% lifetime risk for those
≥55 y/o with normal BP

3. PERIOPERATIV
E
HYPERTENSIO
N
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HTN is the 2nd most
common risk factor
associated with surgical
morbidity (1st is
smoking).
Perioperatively, may occur
during induction of anesthesia.
• Intra-op, it is associated with
PAIN-induced sympathetic
stimulation, HYPOTHERMIA,
and/or HYPOXIA.
• Or excessive IVF therapy –
persists 24-48hrs post-op
Post-operatively:
• Due to discontinuation
of antihypertensives
• Incidence: 4-30%
following surgery

4. Classification
of
BP
in
Adults
(≥18y/o)
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CLASSIFICATION
SYSTOLIC
BP (mmHg)
DIASTOLIC
BP (mmHg)
Normal <120 AND <80
Prehypertension 120-139 OR 80-89
Stage I HTN 140-159 OR 90-99
Stage 2 HTN ≥160 OR ≥100

5. ETIOLOGY
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• Cannot be cured but can be controlled
• Genetic factors play an important role
• Develop gradually over many years
>90% UNKNOWN: classified as
PRIMARY or ESSENTIAL HTN
• MCC: HTN associated with kidney
impairment like CKD and renovascular HTN
• Appear suddenly, and causes higher BP
values
<10% have SPECIFIC CAUSES:
classified as SECONDARY HTN

6. Causes
of
Secondary
Hypertension
(JNC
VIII:
2015)
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DISEASE STATES DRUGS AND OTHER PRODUCTS
• Kidney disease
• Adrenal gland
tumors
• Thyroid disease
• Congenital blood
vessel disorders
• Alcohol abuse or
chronic alcohol
abuse
• Obstructive sleep
apnea
• NSAIDs: e.g., ibuprofen, naproxen
• Birth control pills
• Decongestants: pseudoephedrine,
phenylephrine
• Cocaine
• Amphetamines: e.g.,
amphetamine, methylphenidate,
lisdexamfetamine
• Corticosteroids: e.g., prednisolone,
methylprednisolone,
dexamethasone, hydrocortisone
• Food: foods high in sodium such as
canned or processed foods, salad
dressings, cheese, chips, sweets
• Alcohol

7. CONSEQUENCE
S
Important cause of
premature death: 7.5M
deaths annually
HTN damages blood
vessels and organ
function: ending up with
heart attack, stroke,
CHF and kidney disease
If it causes
atherosclerosis in the
HEART: angina, CHF or
MI
In the brain: may
weaken blood vessels
forming aneurysms, or
atherosclerosis causing
stroke
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8. PATHOPHYSIOLOGY
Complex
pathophysiology
Endothelial
dysfunction
Increased
vascular
resistance &
vasoreactivity
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Baroreflex
is reset to
higher BP
levels
•Hypertensive patients tolerate
HTN crisis quite well with noted
maintenance of blood flow to
organs
•But are less protected to drops
in BP: occurrence of
hypotension, even if not in
dramatic levels, may cause end-
organ damage

9. PATHOPHYSIOLOGY
9
Endocardium ischemia (even
without coronary disease)
tachycardia
LV
hypertrophy
hypotension

10. PREOPERATIV
E
HYPERTENSIO
N
At least 25% of
patients undergoing
noncardiac surgery
Usually doesn’t
involve end-organ
damage, with enough
time to reduce BP
DBP ≥110 mmHg:
marker of
perioperative cardiac
complications in px
with chronic HTN
Associated with:
• Perioperative bradycardia,
tachycardia, hypertension
• 3.8x increase in post-op
death (compared with
normotensive patients)
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11. PREOPERATIV
E
HYPERTENSIO
N
Work-up for secondary
causes:
• Pheochromocytoma – rare, but
may produce vasoconstriction and
hypovolemia, complicating
management
Clonidine withdrawal
syndrome – present 18-24
hrs after sudden
discontinuations of
clonidine
• Treated with IM clonidine or
labetalol and methyldopa
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12. INTRAOPERATIV
E
HYPERTENSION
Considered HYPERTENSIVE
EMERGENCY if there is >20%
acute increase in BP during
surgery
Occur more commonly in
patients undergoing surgery of:
• Carotids
• Abdominal aorta
• Peripheral vascular procedures
• Intraperitoneal surgery
• Intrathoracic surgery
May precipitate MI or CHF in a
patient with preexisting LV
dysfunction
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13. Consequences
of Anesthesia on
Hemodynamics
of a
Hypertensive
Patient
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14. Interactions
Between
Anesthetics and
Antihypertensiv
e Drugs
Main concern: effect of anesthetics on the
sympathetic NS
• Especially during fast or extended sympathetic
blockade
• Propofol: reduces vascular response to
norepinephrine, angiotensin II & vasopressin (effect
amplified in hypertensive patients)
• Hence, catecholamine-resistant hypotension (or
refractory hypotension).
But, no evidence justifies withdrawal of
antihypertensives prior to surgery
• Chronic tx should be given till the day of surgery if
rebound HTN can occur (e.g., on beta-blockers or
clonidine)
• Or stopped the day before for most treatments
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15. ACUTE
POSTOPERATIVE
HYPERTENSION
Definition:
• SBP >190 mmHg and/or
• DBP >100 mmHg
• On 2 consecutive readings
after surgery
Usually occur in the
first 20 minutes of the
post-op period
• Resolution can require up
to 3 hours
If untreated,
increases risk of:
• MI
• CVA
• Bleeding
Characterized by:
• Peripheral
vasoconstriction
• Catecholamine release
• Reduced baroreceptor
sensitivity
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16. ACUTE
POSTOPERATIVE
HYPERTENSION
Presents in patients
with intra-op HTN,
excessive pain &
inadequate
ventilation
MYOCARDIAL
ISCHEMIA:
•Most commonly occurs
post-op, may present hours
to days after surgery
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17. Management
of
Hypertensive
Patients
Other causes of HTN should be
addressed:
• Pain
• Hypoxia
• Hypercarbia
• Agitation
• Bladder distention
• Hypervolemia
Distinguish between
Hypertensive Urgency and
Emergency:
• Emergency: with coexistent end organ
damage, requires IV antihypertensive
Goal BP:
• 25% decrease in systolic BP
• Reduce DBP by 10-15% or to 110 mmHg
in 30-60 minutes
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18. Management
of
Hypertensive
Patients
Pre-op
Know the HTN classification
Determine the kind/number
of anti-HTN drugs being used
Identify end-organ damage
Ideally, 2D-echo must be
done to assess LV
hypertrophy
Intra-op
Anesthesia induction should
be titrated
BP monitoring: thru an
automated cuff
(intermittent), or an arterial
line (continuous)
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19. Management
of
Hypertensive
Patients
For Hypotension
IV fluids
Sympathetic agonists:
ephedrine, phenylephrine
Terlipressin: vasopressin
agonist, as effective as
norepinephrine, but
increases serum lactate
For Hypertension
Adequate pain control
Prevent shivering
Titratable IV treatment:
• Nicardipine
• Urapidil
• Esmolol
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22. Management
of
Hypertensive
Patients • Beta-blockers
• Statins
• ACE-inhibitors/ARBs
Chronic anti-HTN
treatment should be
resumed ASAP.
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23. LONG-
TERM
TREATMEN
T
Lifestyle
Modification
Limit sodium intake to
<1.5g per day.
DASH diet – high in fruits,
veggies, whole grains,
poultry & fish
Restrict alcohol intake:
•0-2 drinks/day for males
•0-1 drinks/day for females
40 minutes of moderate to
vigorous intensity aerobic
exercises 3-4x a week
Pharmacological
Therapy
Thiazide diuretics
Long-acting calcium-
channel blockers
ACE-inhibitors
Angiotensin II Receptor
Blockers (ARBs)
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24. LONG-
TERM
TREATMEN
T
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BLOOD PRESSURE GOALS
Population
BP Goal
(Systolic/Diastolic)
<60 years old <140/90
≥60 years old <150/90
Chronic Kidney Disease
(CKD)
<140/90
Diabetes <140/90

25. HAVE A GOOD DAY!

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