2. Global Burden Of Hypertension
Ref: https://www.who.int/news-room/fact-
sheets/detail/hypertension#:~:text=An%20estimated%2046%25%20of%20adults,cause%20of%20premature%20death%20worldwide.
▪ An estimated 1.28 billion adults aged 30–79 years worldwide have hypertension,
most (two-thirds) living in low- and middle-income countries
▪ An estimated 46% of adults with hypertension are unaware that they have the
condition.
▪ Less than half of adults (42%) with hypertension are diagnosed and treated.
▪ Approximately 1 in 5 adults (21%) with hypertension have it under control.
▪ Hypertension is a major cause of premature death worldwide.
▪ One of the global targets for noncommunicable diseases is to reduce the
prevalence of hypertension by 33% between 2010 and 2030.
5. Average Percentage of Reduction
Stroke Incidence 35-40%
Myocardial Infraction 20-25%
Heart Failure 50%
Benefits of Lowering BP
6. Impact of Hypertension on CVD
▪ Risk of HF increases 2-3 fold in HTN.
▪ In-hospital mortality in HHF is 2.4-10%; 13-15% among Asians.
▪ HHF can be reversed by effective control of BP.
▪ HTN doubles CAD risk.
▪ Shear stress of HTN promotes atherosclerosis.
▪ Rupture of plaque by acute severe rise in BP precipitates MI.
7. Impact of Hypertension on CVD
▪ Hypertensive patient are prone to develop Atrial fibrillation, PVC,VT.
▪ The incidence of Sudden Cardiac Death also increases in LVH caused by
HTN.
▪ HTN is strongly. Independently, and linearly associated with the risk of
Stroke.
▪ Among stroke risk factors HTN(79.2%).
8. 50%
The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure
20
mmHg
SBP
increase
Mortality from
IHD & Stroke
Prospective Studies Collaboration. Lancet. 2002;360:1903-1913
SBP versus Mortality
9. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure
10%
2
mmHg
SBP
decrease
Mortality from
IHD & Stroke
Prospective Studies Collaboration. Lancet. 2002;360:1903-1913
Even a small decrease is
beneficial
10.
11. 2020 ISH Hypertension Practice
Guidelines
11
ISH 2020 guidelines were
developed
To be used Globally
To be fit for application low and
high resource setting
To be concise, simplified and
easy to use
14. Office Blood Pressure Measurement
● 2-3 office visits at 1-4-week
intervals.
● Whenever possible, the diagnosis should not
be made on a single visit (unless BP
≥180/110 mmHg and CVD).
● If possible and available the diagnosis of
hypertension should be confirmed by out-of-
office measurement.
Blood Pressure Measurementand Diagnosis ofHypertension
16. Home BP monitoring, before each visit to the
health professional
2 X 2 = 4
2 measurements on each occasion
2 occasions in a day (morning and evening)
4 days in a week
20. Peri-operative Hypertension Importance
▪ Increased risk of cardiovascular events.
▪ Increased post-operative morbidity and mortality.
▪ Association with end-organ damage.
21. Perioperative Hypertension occurs during
a) Induction of anesthesia
b) Intraoperative due to pain induced sympathetic stimulation
c) Hypothermia
d) Hypoxia
e) Intravascular volume overload
f) 24 to 48 hours post op as fluid is mobilized from extravascular space
25. How to diagnose perioperative HTN
▪ No clear guidelines exist on the optimal blood
pressure in the preoperative period.
▪ Ideally the clinician need to use target blood
pressure in the general population in the
ambulatory settings.
▪ Single reading of elevated BP in patient with
previous undiagnosed or untreated HTN is not
reliable. Subsequent readings in non-stressful
environment required to avoid the diagnosis of
white-coat HTN.
▪ For treating systolic or diastolic hypertension, a
20% increase over the baseline often defines a
treatment threshold.
26. Pathophysiology and etiologies of perioperative HTN
The etiology of uncontrolled hypertension in the perioperative period is multifactorial
▪ Early discontinuation of long-term antihypertensive regimen.
▪ Induction of anesthesia (especially if no opioid analgesia is used).
▪ Intraoperatively (associated with acute pain-induced sympathetic stimulation that
leads to vasoconstriction).
▪ In the early post anesthesia period (associated with pain-induced sympathetic
stimulation, hypothermia, hypoxia, or as a result of intravascular volume overload
from excessive intraoperative intravenous fluid therapy).
27. Pathophysiology and etiologies of perioperative HTN
Other causes of hypertension during anesthesia are related to the
▪ Hypoxemia and hypercapnia.
▪ Overdose of the drugs being used intraoperatively such as vasoconstrictors
and inotropes.
▪ Malignant hyperthermia.
28.
29. Blood pressure goal
There is paucity of recommendations for hypertension management specifically in the
perioperative setting-
▪ According to ACC/AHA perioperative guidelines, Stage 1 or Stage 2 hypertension is
not an independent risk factor for perioperative cardiovascular complications.
▪ However, uncontrolled stage 3 hypertension (systolic blood pressure ≥180 mmHg or
diastolic blood pressure ≥110 mmHg), constitutes a risk factor for perioperative
ischemic events.
30.
31.
32. Steps of Assessment
Step 1-Determine Type of
surgery(e.g., emergency)
Step 2-Any active cardiac
condition(e.g., CAD, HF)
Step 3-Determination of surgical
risk/severity
Step 4-Patient`s functional capacity
Step 5-Futher invasive test if
functional status is poor
33. Cardiovascular Risk stratification
Major Intermediate Minor
Unstable Coronary syndrome Mild Angina Pectoris Advanced Age
Decompensated Heart failure Previous myocardial infarction Rhythm other than sinus(AF)
Significant Ventricular Arrhythmias Compensated Prior Heart Failure Low functional capacity
Severe Valvular Disease Diabetes Mellitus on Insulin History of Stroke
Renal Insufficiency Uncontrolled Hypertension
35. Cardiac Risk Stratification based on surgical procedure
Ref Circulation 1996;93:1278
High(Cardiac Risk >5%) Intermediate(Cardiac Risk 1-5%) Low(Cardiac Risk <1%)
Emergency major operations,
particularly in the elderly
Carotid Endarterectomy Endoscopic procedure
Aortic and other major vascular open
surgeries
Head & Neck Surgery Superficial procedure
Peripheral Vascular Surgeries Intraperitoneal and intrathoracic
Surgery
Cataract surgery
Anticipated prolong surgeries
associated with large fluid shift
and/or Blood loss
Orthopedic Surgery Breast Surgery
Prostate Surgery
36. Preoperative Concerns
▪ All elective surgery patients with cardiovascular risk factors should undergo
preoperative optimization- control of BP, correction of electrolytes, cessation of
smoking, glucose control etc.
▪ Hypertension mild or moderate & no associated metabolic or cardiovascular
abnormalities- do not delay surgery.
▪ Surgery should be cancelled in patients with hypertensive end organ damage till
cardiovascular status is optimized.
▪ Anesthesia and surgery not to be cancelled only on grounds of elevated preoperative BP, defer if
end-organ damage present. (Howell et al. BJA 2004;92(4):570-583)
37. Preoperative Concerns
▪ Patients with chronic HTN with DBP <110 mm of Hg- don’t delay surgery.
▪ Urgent situations- rapidly acting parenteral agents to be used.
▪ Patients with newly diagnosed mild hypertension, treatment may be
delayed till after surgery.
38. Preoperative Concerns
▪ Hypertensive patients must continue their anti hypertensive drugs perioperatively.
▪ ACEi and AT 2 receptor antagonists associated with intraoperative hypotension-
discontinue at least 10 hours before surgery.
▪ Symptoms of clonidine withdrawal syndrome are typically encountered 18 to 24 hours
after sudden discontinuation of clonidine in patients taking more than 1.0 mg/day.
▪ Clonidine patch preoperatively or Dexmedetomidine, an IV rapid-acting a-2 adrenergic
agonist, may have utility in patients with clonidine-withdrawal syndrome.
39. Preoperative Concerns
Preoperative β blockers:
▪ Proven to be beneficial in cardiac surgeries.
▪ For non-cardiac surgeries good results in high-risk patients but not in low-risk
patients (NEJM 1996, 2005).
▪ Associated with lesser incidences of perioperative ischemia.
▪ Intraoperative hypotension, precipitation of asthmatic attack, major
disadvantage.
40. Intraoperative Concerns
Target range for intraoperative BP control:
▪ BP days to weeks before surgery
▪ Presence of associated comorbidity
▪ Type of surgery
Maintained within 20% of the preoperative level.
Acute elevations in blood pressure (>20%) in the intraoperative
period are typically considered hypertensive emergencies
(Goldberg and Larijani 1998)
41. Intraoperative Concerns
Stressful intraoperative events:
▪ Intubation
▪ Surgical incision
▪ Emergence from GA and extubating.
During induction – Normotensive: BP rises by 20- 30 mm of Hg, HR by 15 to 20 bpm
- Untreated HTN- SBP rises by up to 90 mm of Hg and HR by 40 bpm
Patients with preexisting HTN – more intraoperative labile BP leading to myocardial
ischemia.
42. Intraoperative Concerns
Other causes of intra-operative hypertension:
▪ Inadequate depth of anesthesia
▪ Pain
▪ Hypercarbia
▪ Hypoxemia
▪ Bladder distension
▪ Hypervolemia
Exaggerated response in hypertensive patients
▪ Increased sympathetic tone
▪ Decreased intravascular volume
43. Intraoperative Concerns
▪ Achieving hemodynamic stability more important than targeting an arbitrary
intraoperative BP.
▪ Reduction of DBP by 10- 15% or to approx. 110 mm of Hg over a period of 30 to 60
min.
▪ Concurrent gentle volume expansion to restore organ perfusion and to prevent
sudden decline in BP after initiation of Anti hypertensive.
▪ Chronic hypertensive – cerebral and renal autoregulation shifted to higher range –
more prone to hypoperfusion if BP lowered rapidly.
44. Postoperative concerns
▪ APH(Acute Post operative hypertension) has been defined as a significant elevation in
BP during the immediate postoperative period that may lead to serious neurological,
cardiovascular, or surgical-site complications and which requires urgent management.
▪ There is no standardized definition for this disorder.
▪ Postoperative hypertension (arbitrarily defined as systolic BP ≥190 mm Hg and/or
diastolic BP 100 mm Hg on 2 consecutive readings following surgery) (Plets
1989; Chobanian et al 2003b)
▪ Postoperative hypertension often begins ~10–20 minutes after surgery and may last up
to 4 hours (Towne and Bernhard 1980)
45. Postoperative concerns
▪ Pathophysiologic mechanisms :
- Activation of the sympathetic nervous and renin-angiotensin systems.
- Alterations in intravascular volume.
- Anxiety.
- Pain.
- Anaesthesia emergence,
- Shivering, drug side effects, underlying HTN, and vascular disease.
46. Postoperative concerns
▪ Activation of the sympathetic nervous system seems to be a fundamental
component of Acute Post operative hypertension, as evidenced by elevated plasma
catecholamine concentrations in these patients.
▪ The primary hemodynamic alteration observed in Acute Post operative hypertension
is an increase in afterload with an increase in SBP and DBP with or without
tachycardia.
47. Postoperative concerns
Implications:
▪ Risk of hemorrhage.
▪ Disruption of vascular or cardiac suture lines.
▪ Cerebral edema.
▪ ↑ myocardial wall stress and oxygen consumption→ myocardial ischemia.
48. Postoperative concerns
▪ Pain and anxiety are common contributors to BP elevations and should be
treated before administration of antihypertensive therapy.
▪ Intravascular volume depletion increases sympathetic activity, and a volume
challenge should be considered.
▪ Other potentially reversible causes of APH include hypothermia with
shivering, hypoxemia, hypercarbia, and bladder distension
49. Treatment
▪ The approach to the treatment of perioperative hypertension is considerably different
than the treatment of chronic hypertension (Levy 1993).
▪ The initial approach to treatment is prevention.
▪ Hypertension due to tracheal intubation, surgical incision, and emergence from
anaesthesia- treated with short-acting β-blockers, ACE inhibitors, CCB or vasodilators (
Weiss and Longnecker 1993).
▪ Because many patients that develop postoperative hypertension do so as a result of
withdrawal of their long-term antihypertensive regimen, this withdrawal should be
minimized in the postoperative period
▪ Postoperative - rebound hypertension after withdrawal of antihypertensive medications,
hypertension resulting in bleeding from vascular surgery suture lines, hypertension
associated with head trauma, and hypertension caused by acute catecholamine excess
(eg, pheochromocytoma). An initial approach is to reverse precipitating factors (pain,
hypervolemia, hypoxia, hypercarbia, and hypothermia).
50. Treatment
▪ The general perioperative strategy suggested is to maintain blood pressure within
20% of preoperative values with the purpose to prevent end organ hypoperfusion
One important issue should be considered when treating the blood pressure in
surgical patients
▪ Due to the shift in the autoregulatory system with chronic hypertension, these
patients are often able to tolerate a higher blood pressure level but unable to
tolerate significant degrees of hypotension compared with usually normotensive
individuals
51. Treatment - Uncontrolled HTN (>180/110mmHg)
For urgent or emergency operations
For urgent or emergency operations, the risks of uncontrolled hypertension during
general anesthesia and surgery must be weighed against the risk of end organ
hypoperfusion caused by the need to decrease blood pressure acutely allowing safe
performance of surgery
This situation mandates
▪ Careful and precise titration of a rapid acting antihypertensive agent
▪ Close monitoring of arterial pressure and end organ function to minimize the risk of
adverse cardiovascular events
52. Treatment
Delay or defer surgery?
There is a lack of data to support delay of surgery
▪ When BP is mildly elevated at the time of surgery (<180/110), rapid reduction in BP
is not necessary, and studies have been unable to demonstrate a benefit of delaying
surgery
▪ In patients with stage 3 hypertension, deferring surgery was recommended,
especially with other cardiovascular risk factors and target organ damage that may
further increase the perioperative risk
53. Pharmacological therapy
Beta blockers
▪ It is optimal to continue beta blockers in patients who are already taking
these medications including the morning of surgery with sips of water.
▪ If patients are at intermediate or high cardiovascular risk, consideration is
given to begin a beta blocker in the preoperative period.
▪ This medication should be started at least 1 day prior to surgery, and ideally 1
week prior to the surgical intervention.
▪ A low dose should be initiated and carefully up titrated. Beta blockers should
not be started on the morning of surgery. The dose might be Metoprolol 12.5
twice a day, or Bisoprolol 2.5 mg daily.
54. Pharmacological therapy
Alpha-2 agonists (Clonidine)
▪ It is optimal to continue clonidine in those patients who are already taking this
medication.
▪ This medication should not be initiated in the preoperative period with the intent of
providing cardiac protection.
55. Pharmacological therapy
Calcium channel blockers
▪ It is ideal to continue these medications in the perioperative period, including the
morning of surgery.
▪ These medications are usually well tolerated in the perioperative settings, and do not
result in an exaggerated hypotensive response after induction of anesthesia.
▪ Both Dihydropyridines and Non-Dihydropyridines can be continued with the caveat that
the latter can cause bradycardia.
▪ Patients receiving calcium channel blockers may have an increased incidence of
postoperative bleeding, probably due to inhibition of platelet aggregation.
▪ The multiple benefits of these drugs probably outweigh the small risk of continued
therapy.
56. Diuretics
▪ There is no supportive data to guide dosing this group of medications in the
perioperative period
▪ Due to potential for volume depletion and electrolyte disturbance, it is ideal
to hold these medications on the morning of surgery in most cases
57. ACE inhibitors (ACE-I) and Angiotensin receptor
blockers (ARBs)
▪ The use of these medications on the morning of surgery is controversial.
▪ ACE-I/ARBs should be held on the morning of surgery in most cases.
▪ ACE-I/ARBs increase the rate of hypotension requiring vasopressor agents, usually at
the time of anesthesia.
▪ It is imperative to resume these medications in the postoperative period within 2
weeks following surgery.
58. Pharmacological therapy
Additional antihypertensive medications such as
▪ Hydralazine
▪ Alpha blockers
▪ Methyldopa
Can be continued in the perioperative period and can be administered on the
morning of surgery.
Although not considered as a true antihypertensive medication, Nitrates can
be given on the morning of surgery with sips of water.
60. Intraoperative period
Patients with intraoperative hypertension should be managed with
intravenous medications with close titration of the blood pressure response
62. Postoperative period
▪ Acute postoperative hypertension usually develops within 2 hours of surgery and
can resolve within a few hours after treatment
▪ Until oral intake is resumed, antihypertensive medications used prior to surgery
can be resumed in intravenous or topical formulations
▪ It is important to resume beta blockers and alpha-2 agonists without prolonged
interruption to avoid rebound hypertension and tachycardia
63. Postoperative period
▪ Calcium channel blockers can be resumed as the blood pressure stabilizes
▪ Diuretics and ACE-I/ARBs can be resumed on postoperative days 1 to 3, as blood
pressure and fluid status dictate
▪ Hydralazine, nitrates, and alpha blockers should be resumed postoperatively as the
physiological status dictates
64. Device-Based Therapies
2017 ESH/ESC guidelines state that various device-based therapies are
available:-
▪ Carotid baroreceptor stimulation (pacemaker and stent).
▪ Renal denervation.
▪ Creation of an arteriovenous fistula (ie, ROX coupler)
65. Take home message
▪ Adequate blood pressure control must be maintained in all three perioperative
(pre, intra and postoperative) settings, as its instability is associated with multiple
adverse events
▪ Careful assessment of the adequacy of chronic blood pressure control and early
identification of target organ damage is paramount
▪ Patient with preoperative uncontrolled stage 3 hypertension pose the greatest
risk for perioperative cardiovascular complications
▪ The goal is to maintain mean arterial pressure within 20% of baseline values
when possible
66. Take home message
▪ Several therapeutic options are available to be used perioperatively, and when the
oral intake cannot be resumed postoperatively, options are available in
intravenous or patch form
▪ Antihypertensive medications should be continued until the day of surgery with
exception of renin-angiotensin-blocking agents and diuretics those are to be
resumed after the surgery.
▪ By implementing evidence-based practices and adopting a multidisciplinary
approach, we can make a significant impact on reducing perioperative
complications related to hypertension.
67. References
▪ Perioperative hypertension management- (Joseph Varon and Paul E Marik ) - Vasc
Health Risk Manag. 2008 June; 4(3): 615–627
▪ Perioperative Hypertensive Crisis:Newer Concepts (Manuel L. Fontes , Joseph
Varon)-International Anesthesiology Clinics Volume 50, Number 2, 40–58
▪ Management of Perioperative Hypertensive Urgencies With Parenteral Medications
(Kartikya Ahuja , Mitchell H. Charap)- Journal of Hospital Medicine
▪ Hypertensive Crisis- (Maria Alexandra Rodriguez, Siva K. Kumar, Matthew De Caro)-
Cardiology in Review 2010;18: 102–107
72. Case Scenario 1
▪ A 45 year old hypertensive lady, proposed for laparoscopic
cholecystectomy under G/A, has been referred to cardiologist with
the summary
BP 170/100 mmHg (At morning on the day of surgery)
Used to take 1. Olmesartan 20mg + Amlodipine 5mg-
(Combination pill) once daily at evening
2. Bisoprolol 5mg once daily at morning
ECG – LVH with strain
RFT reveals unremarkable
73. Case Scenario 2
▪ A 65 year old diabetic and hypertensive gentleman has been
proposed to have TURP. On the morning of surgery, while attending
the call, Cardiologist noticed that his BP was 190/115 mmHg
The patient used to take Losartan potassium 50 mg +
thiazide 12.5 single combination pill
His Serum creatinine - 1.7 mg/dl
74.
75.
76.
77.
78.
79.
80.
81. Conditions constituting evidence of EOD
▪ Hypertensive encephalopathy
▪ Intracerebral heamorrhage
▪ Stroke
▪ Head trauma
▪ Ischemic heart disease (most common)
▪ AMI
▪ Acute LVF with P/oedema
▪ Unstable angina
▪ Aortic dissection
▪ Eclampsia
▪ Life threatening arterial bleed
