HTN and IHD Flashcards
HTN is defined as SBP above ______ and DBP above ______
140
90
classic medicine involves sub-dividing any interval into ________ ______
smaller increments
HTN affects ____ of the global population
25%
_____ of surgical patients in the US will have HTN
1/3
______ ______ more frequently affected than caucasian
african american
prevalence is higher in men except at extremes of _____ where women are higher
age
HTN is an independent risk factor for _______ and ______ when left untreated
morbidity and mortality
small percentages of patients present with HTN r/t another _____ _____
system pathology
most of the time, it is not a _______ issue but we should be watching for unanticipated HTN
secondary
90-95% of pts with HTN have “_______ ______” which is unknown origin
essential HTN
if you consider the worsening of a pathology, a gradual progression of essential HTN should be ________ prior to presentation at the _____ _____
intercepted
severe level
diagnosis might include several readings to obtain an ______ (______) hypertensive state
average (sustained)
we know that there are several causes of HTN and a high reading might not reflect ________
pathology
3 essential systems that impact BP
- ANS
- RAAS
- vascular endothelium substance production
ANS encompasses:
HR x SV x SVR
primarily manages ______ term and ______ change
short
rapid
input from _____-______ and cardiac and peripheral receptors that automate cardiac and vascular function
baro-receptors
correlates with _____ and ______ response
[ANS]
inflammatory and stress
innervation of the sympathetic chain and subsequent peripheral nerves controls vasculature ________ and ______ ________ through input of the vasomotor center of the CNS
constriction and cardiac accelerators
stimulation of the ______ ______ can result in sympathetic hormone release
adrenal medulla
_____ _______ directly to an organ may result in excitatory changes
SNS stimulation
release by the _______ of sympathetic hormones _______ & _______ do the same thing but last longer because of metabolism
adrenals
NE and Epi
renal control of pressure includes control/excretion of ________ _______ and the ______ ______ ______ system
extracellular fluid
renin angiotensin aldosterone system
RAAS increases ______ ______ (intermediate term) and retention of _______ (long term)
vascular tone
fluid
renin from kidney is stimulated by ____ ______ ______
low arterial pressure
allows conversion of ________ to ________
angiontensinogen to angiotensin I
angiotensin I is converted to angiotensin II by ______ in the lung. It is _______ acting but a potent _______
ACE
short acting
potent vasoconstrictor
AT II also decreases excretion of _______ resulting in increased fluid retention in the _______
fluid
vasculature
AT reduces blood flow through the kidneys by _______ and thus decreased _______ and increased ________ ______
vasoconstriction
filtration
fluid retention
you cant lose fluid if it isnt _______ out, risk for _______
filtered
AKI
AT stimulates the adrenal glands to secrete ________. this results in increased reabsorption of fluid in the kidneys. ______ & ______ retention and _______ excretion
aldosterone
sodium and water
potassium
renal path
afferent arterioles > glomerulus > efferent arterioles > proximal tubules > loop > distal tubule > collecting duct
ANP is from the
atria
BNP is from the
ventricles
a high ANP does NOT
stimulate renin
low ANP
stimulates renin
renin cascade end result is higher systemic ______ and increased systemic ______-______ ________
pressure
fluid-volume retention
vascular growth can be the result of
hyperplasia
hypertrophy
vasoconstriction can be the result of
direct
via increased noradrenaline release from sympathetic nerves
salt retention can be the result of
aldosterone secretion
tubular Na+ reabsorption
VESP
nitric oxide results in _______ - produced naturally to counteract unopposed _______ forces
dilation
vasoconstrictive
endothelin results in ________ - produced naturally in vascular walls
constriction
endothelin is released primarily during vascular insult to _______ ______
control hemorrhage
ANP and BNP - released in the _______ and cause _______
heart
vasodilation
(we see high BNP in volume overload)
inflammatory and stress response on the vasculature can inhibit ______ ______ and result in positive feedback loop with _______ - progressively higher pressures
natural response
endothelin
actions or drugs can stimulate or inhibit the natural response of ______ and ______ effecting blood pressure
nitric or endothelin
competing forces are the _____ and _____
nitric and endothelin
bc short term manipulation is controlled by the ______, our anesthetic pharmacology often addresses manipulation of these componenets
ANS
stressors of surgery and anesthesia are not the same as
day to day life
BP is like other anesthesia goals - balance the effect of _______ against ______
surgery
normality
bc stress of surgery often stimulates ANS responses, our mitigation addresses these components:
1. _______ and sympathetic ______-______ fxns are concurrently stimulated
2. inhibition of PNS ______ _______ to the heart
3. both ______ and ______ are constricted
vasoconstrictor and sympathetic cardio-accelerators
vagal stimulation
arteries and veins
the resulting constriction increases ____ while an increased ____ and force of contraction increase ______
BP
HR
SV
increased stretch in the baroreceptors stimulates a reduction in __________
pressure
impact is a manipulation of the ______ elements of the ______. increased/decreased vagal stimulation results in the ability to change _____ and thus ______
parasympathetic elements of the ANS
HR and thus CO
practical example is change of body position when superior aspects of the body lose pressure and the ______ and _________ allow for reperfusion of brain and torso
CO and vasoconstriction
HR increases by inhibiting the baseline ______ _____
vagal stimulation
bainbridge reflex manipulates CO but not for the benefit of _____ _____ ______
blood pressure control
in response to an increase in atrial pressure, _________ stimulation results in increased or decreased stimulation to the heart for ______ ______
parasympathetic
rate control
this reflex addresses increases in blood volume to “_____” the heart
unload
effect of HTN on the general population correlates with:
vasculopathy/PVD
end organ damage
ischemic heart disease
cerebrovascular disease
stroke
aortic disease; specifically aneurysm
neuopathy
meaning that HTN results in all of these changes due to changes in vessel _______ and ______ _______
compliance
decreased flow
essential HTN addresses one or more of the primary ________ of BP
generators
“fixing the problem at its source”
ANS - drugs are used to blunt the _____, _____, and ______
HR, SV, and SVR
Renin/AT system - drugs reduce volume or intercede in one of the conversion processes to _____ ______
dilate vessels
endothelium vasodilation drugs - improve or enhance the direct acting dilation effect of ______
NO
as a general rule, beta blockers are reserved for _____ ____ _____ patients and not as a first line therapy for ______ ______
coronary artery disease
essential hypertension
some gains have been made by re-perfusing the kidney if _____ ______ ______ is thought to be the cause of renin/AT activation
renal artery stenosis
for long term control, renal blood ______ is increased or reabsorption of salt and water is _______
[addressing the problem]
flow
decreased
increased blood flow is accomplished by any number of
vasodilators
drugs that decrease reabsorption block the movement of ______ in ______
sodium in tubules (diuretics)
one thing to consider when choosing medications is the specific “______” being fixed or the _____ of intervention needed
problem
speed
general expectations are that the patient will continue their normally scheduled ___________ meds
anti-hypertensive
some exceptions are made with ______ and ______ drugs due to the likelihood of significant ________ intraop. UNLESS:
ACEIs and ATIIRBs
hypotension
UNLESS part of cardiac risk reduction
_____ ______ already scheduled are always continued bc they are primarily being used for ______ effect
beta blockers
cardioprotective effect
beta blockers are not routinely administered ________ in the absence of a schedule for ______ ______
prophylactically
essential HTN
general consensus is that essential HTN wont be cured in periop period and patient specific pressure should be maintained with the exception of _______ _______ pressure (____)
extraordinarily high pressure (> 180 SBP)
_____ pressure monitoring may be warranted, continuous ______ management of volume and heart fxn can be useful
arterial
TEE
_______ is of greater value than the absolute number and _______ is BETTER than _______ pressure
stability
higher is BETTER than lower pressure
drugs affecting HR/SV:
CCBs: cardizem, cleviprex, cardene
BBs: labetolol, esmolol, metoprolol
direct acting vasodilators
nitroglycerin, nitroprusside, hydralazine
pulm HTN value
mean PAP > 25 mmHg
PHTN diagnosed by _______ and clinically useful assessment by _____
RHC
TEE
PHTN can occur in several ways:
vascular abnormality and vasoconstriction
left heart failure leading to right heart failure
combined increase PVR with chronic disease (shunt response through HPV)
some of the more common causes are:
COPD/lung dz
OSA (as much as 50% of pts with OSA/hypoventilation have PHTN)
LVF
drug induced PHTN
parenchymal lung dz such as sarcoid and fibrosis
pa pressures - inflating the balloon captures the data on the ____ side of the balloon without the _____ side
distal
proximal
distal pressures can result in effects ______ (high PA may result in high ____/____)
proximally
RA/CVP
prostanoids treat PHTN - produce _______ and decrease ______ ______/_______ response
vasodilation and decrease platelet effect/inflammatory response
endothelin receptor antagonist treats PHTN - allow natural effect of NO to function by inhibiting _______
endothelin
nitric oxide treats PHTN - directly dilates by stimulating _____ in smooth muscle
cGMP
NO is degraded by _______
PDE
thus _____ _______ can increase the effect of NO
PDE inhibitors
caution on cases to avoid natural _______ ______ ______ that might be stimulated by hypoxia, underventilation, high PEEP, or by surgical effects from one lung ventilation, etc
hypoxic pulmonary vasoconstriction
following induction, pressure may _____ and then it takes a LOT of medication to to ____ ____ _____
drop
bring it up
______ _______ may result as inhalation agent diminishes and heart rate acutely ______
emergence tachycardia
increases
ex: in a patient that has been on a neo gtt to this point, the _______ will quickly increase HR
ANS
______ dc’d and ______ given and within a minute heart rate will return to baseline
Neo
esmolol
38 YOF w/ significant HTN arrives to OR for left leg revascularization. Her arrival pressure is 196/112. She takes 7 different classes of anti-hypertensives which she took as scheduled today. You plan an IV induction with standard dosing of medication for general endotracheal anesthetic. After administering the medications, your blood pressure when you look up from intubation is 65/32. Should you….
treat hypotension aggressively?? by reversing…..
beta agonists for beta blockade
calcium for calcium channel blockade
vasoconstrictors (alpha agonists) for alpha blockers and RAS blockade
following an uneventful anesthetic for a total knee replacement, a patient is emerging from anesthesia and you notice a rapidly increasing pressure. you should know the patient has a history of essential HTN and is taking 3 meds. you should anticipate the blood pressure will continue to climb un-checked, particularly until extubation. note that HTN and intubation can coexist and extubation isnt always the best treatment for HTN you should address HTN with…..
short acting and titratable medications that manipulate the ANS (HR, SV, SVR) such as esmolol
ischemia definition
lack of blood flow somewhere
the heart muscle is the target organ via the _____ _____
coronary arteries
IHD is often a _____ pathology
chronic
_____ ______ is the leading cause of death globally. our patients are going to have it
CV disease
IHD is often described as atherosclerotic _______ disease of the heart, ______ ______ disease, and _______ disease
vascular
coronary artery
coronary
____ and _____ gender are the greatest risk factors
age and male gender
modifiable risk factors for IHD:
- high cholesterol
- smoking
- HTN
- smoking
- obesity
- type A personality (haha)
non-modifiable risk factors for IHD:
- DM
- family hx of IHD
disease occurs when vasculature becomes impaired by ______ _______ or due to _______ from hypertrophy of the muscle or lack of flow from aortic valve disease
plaque development
narrowing
______ vessels lie superficially and _________ vessels lie within the muscle
epicardial
subendocardial
the three major coronary arteries divide into ______ and ______ branches proceed deeper into the muscle
epicardial
subendocardial
generally, vessels are know to perfuse _____ _____ of the heart structure
specific portions
diagnostic testing, such as (3), can isolate the area fed by a specific vessel to determine its individual status
- EKG leads
- TEE regions
- LHC studies
these all look at specific areas
clinical manifestations of poor perfusion can suggest which vessel is compromised based on knowledge of its _____ _____ ______
end perfusion site
vessel that supplies anterior and septal walls of the LV, mitral valve, bundle branches
LAD
vessel that supplies lateral wall of CV
circumflex
vessel that predominately supplies the conduction system (SA, AV nodes), inferior wall of LV
RCA
blood flows through the coronaries predominately during _______
diastole
this picture describes what pathologic process
LVH
increased wall stress leads to left ventricular ______
hypertrophy
diagnostic testing (6)
- stress testing
- heart cath
- echocardiography
- CT scan
- EKG
- Clinical presentation
exercise stress testing - requires _______ but can be mimicked with ______ _______ to stress the heart
exercise
dobutamine challenge
exercise stress testing - looks for EKG changes so ideal candidate would have ______ ______ at the beginning
normal EKG
exercise stress testing - achieved _____ _____ is desirable
target HR
exercise stress testing - ______ ability is an obvious requirement
exercise
exercise stress testing - utilizes a predicted _____ ______
max HR
exercise stress testing - goal is to achieve predicted ____ without _____ changes
HR
EKG
exercise stress testing - negative test correlates with _____ ______ _____
low cardiac risk
exercise stress testing - long term predictions are more accurate with ________ stress than _______ stress tests
exercise
pharmacologic
exercise stress testing - a normal baseline _____ is preferred for accuracy
EKG
exercise stress testing - exercise stress can mimic ______/______ _______ stress and thus proves helpful in predictive values
surgical/anesthesia inductive
exercise stress testing - several components of this stress test are: (2)
- can the patient achieve the predicted HR without symptoms of cardiac incompetency? (SOB/angina/exhaustion)
- are there EKG changes that occur at or before predicted heart rate?
exercise stress testing - if ischemia occurs at HR < 100 =
HIGH risk and < 5 mets
exercise stress testing - if pt tolerates HR > 130 without EKG changes =
LOW risk and > 7 mets
exercise stress testing - the person unable to increase CO/HR in response to stress is at risk like the person who demonstrates ______ changes on the _____ in response to stress
ischemic
EKG
nuclear testing - involves injection of dye while heart is _______
resting/ at rest, imaging the heart for uptake
nuclear testing - after allowing clearance, the heart is ______ and injection of dye is again measured
stressed
nuclear testing - under stress, if coronary disease is present, _____ uptake will occur in the diseased portion due to ______ and coronary ______
less
narrowing
steal
nuclear testing - though sensitive, this test is _____ ______ as it can have _____ ______
not specific
false negatives
(not the most common screening tool)
_____ is GOLD STANDARD for diagnosing IHD, but its not used for screening r/t high cost, risk, and untoward effects
LHC
pts with high risk in anticipation of cardiac sx may receive a _____ or if they have previously failed a stress test
cath (LHC)
_____ is a sensitive tool that can be used to identify the presence of ischemia and can regionalize diseased muscle but lacks ability to quantify vascular compromise which is knowledge needed for grafting
Echo
echo would be helpful for ______/______ but less for _______
management/screening
intervention
_______ ______ testing can be used to identify ischemic events and compare with baseline
12-lead EKG
like echo, this test can be regionalized
12-lead EKG
______ is less expensive and readily available but disease can be masked by electrical abnormalities and is generally less sensitive to ischemic events than other testing materials
EKG
the underlying premise of treatment is to achieve ______ _____ > ______ ______
oxygen supply > oxygen demand
“____ _____” is a catch phrase being used for patients who have ischemia during stress that is not considered to be warranting an intervention
demand ischemia
in anesthesia, our short term goals revolve around decreasing ______ _____ and increasing ______
oxygen demand
supply
IMPORTANT
we work by increasing _____, ______ and _____ ______ pressure
FiO2, Hct, and coronary perfusion pressure
IMPORTANT
we also work by decreasing ______, ______, _______ wall stress, and ________.
HR, contractility, LV wall stress, and pre-load
in the overarching scenario, a patient with identified IHD would receive a therapy to increase supply significantly and in a sustained fashion by such things as: (3)
coronary stent, re-vascularization, CABG
for an acute event, prognosis correlates with ____ _____ of the LV such that poor pumping from acute coronary ischemia results in poorer prognosis
ejection fraction
when to do elective case following a stent placement -
bare metal stents
minimum 30 days
when to do elective case following a stent placement -
drug eluting stents
wait 1 whole year
when to do elective case following a stent placement -
post-CABG
at least 6 weeks
when drug stoppage is appropriate following a stent (ASA/plavix) - (ideally you dont ever come off)
bare metal stents
> 6 weeks
when drug stoppage is appropriate following a stent (ASA/plavix) - (ideally you dont ever come off)
drug eluting stents
> 1 year
3 elements that cause worsening of existing coronary atherosclerosis
- inflammation of surgery
- stress of surgery
- initiation of the clotting cascade
inflammatory response increases the ______ ______ ______
systemic oxygen consumption (greater demand)
increased oxygen demand is normally compensated for by an inherent increase in _____ _____
cardiac output (greater demand)
moderate disease under the effects of surgery can result in increased cardiac oxygen consumption with less supply and subsequent _____
ischemia (higher demand with acute decrease in cardiac blood flow)
goal of pre-op cardiac eval is to identify ______, ________, and ________ of IHD
presence, quantification, implications
clues to a high risk patient (2)
- dyspnea on exertion
- inability to climb 2 flights of stairs (4 mets)
what is a met
amount of oxygen consumed while at rest (3-5ml O2/kg/min)
remember that 1 met is basal oxygen consumption and surgical stress may result in higher O2 consumption than 1 met which is why ___ ______ tolerance is a good predictor for low complication risk
4 met
patient is high risk if surgical procedure is _______ following an MI
< 1 month
risk to patient is 6% if MI within
> 6 months
risk to patient is 15% if MI within
last 3-6 months
risk to patient is 30% if MI within
past three months
ejection fraction equation
EF = (EDV-ESV) / EDV x 100
normal EF is
60-70 (sometimes quoted 50-60)
EF < ____ is impaired
40
peri-op mngmnt of IHD - greatest recommendation is continuation of _____ ______ therapy
beta blocker
peri-op mngmnt of IHD - _____ therapy for lipid lowering effect and anti-inflammatory
statin
peri-op mngmnt of IHD - _____ management to maintain less than 180
glucose
peri-op mngmnt of IHD - support _____ ____
oxygen supply
peri-op mngmnt of IHD - minimizing unnecessary oxygen demand such as (3)
- tachycardia
- hyperdynamic fluctuation
- shivering
peri-op mngmnt of IHD - keeping BP within _____ of baseline for that specific patient
20%
peri-op mngmnt of IHD - blunt SNS response to ______
layngoscopy
peri-op mngmnt of IHD - monitor AT LEAST lead ____ and _____. or optimally lead _____, _____, and ______
II and V5
II, V4, and V5 (practically this is difficult with most machines)
peri-op mngmnt of IHD - maintain _____
Hct
peri-op mngmnt of IHD - overarching goal is optimizing oxygen ______ and ______ while decreasing oxygen ______
supply and delivery
demand
the MOST important factor for reducing myocardial oxygen consumption is ____
HR
HR increases demand for ______
oxygen
HR reduces time in _______ which reduces ______
diastole
supply
oxygen extraction is high in the _______
myocardium
in the presence of ischemia, the options are increase ______ or decrease ______
supply
demand
additional measures to reduce oxygen consumption (3)
- contractility reduction
- wall stress reduction
- volume reduction
normal coronary blood flow is about _____ of CO with ______ extraction
5%
70%
coronary perfusion pressure =
DBP - LVEDP
IMPORTANT
things that affect supply:
- coronary artery anatomy
- diastolic pressure
- diastolic time
- O2 extraction (Hct, SaO2)
IMPORTANT
things that affect demand:
- HR
- preload
- afterload
- contractility
_____ ______ has direct correlation to oxygen consumption
wall tension
wall tension and the duration of that tension can be ______ ______
directly manipulated
wall tension equation
T = LV pressure X LV radius (like a balloon)
to reduce oxygen consumption during ischemic events we can do several things:
- reduce LV pressure by reducing afterload
- reduce duration of contraction by beta blockers/Ca++ channel blockers
- reduce pre-load to have less stretch and thus more contractility
be aware that dilated ventricles will have ______ oxygen consumption (even with low systolic function)
increased
be aware that a hyperdynamic LV and LVH may have increased _____ _____
wall stress
risk reduction strategies: maintain normothermia by (2)
- active warming with forced air
- IV fluid/breathing circuit warming/room temp
risk reduction strategies: avoidance of extreme ______
anemia
risk reduction strategies: control of post-op _____ and _____
pain and shivering
risk reduction strategies: avoidance of _______ moreso than _______
hypotension
hypertension
risk reduction strategies: maintenance of _______
normovolemia
risk reduction strategies: post-op ______ management
glucose
risk reduction strategies: NO recommendation toward use of _____, continuous _____, or _______
PAC
TEE
IV NTG
risk reduction strategies: the use of PAC can be considered when the disease affects ________ and cannot be corrected before surgery
hemodynamics
risk reduction strategies: TEE is for _____ events or persistent ________ instability or known ______ disease
acute
hemodynamic
valve
risk reduction strategies: _______ ______ are acceptable
inhalation agents (no change vs TIVA)
risk reduction strategies: recommend against high dose _____ technique due to secondary post op ventilation issues
opioid
risk reduction strategies: regional anesthesia showed ____ ________ in cardiac risk and may _______ pulm outcomes
no difference
improve
risk reduction strategies: avoidance of _______ with AI
bradycardia
risk reduction strategies: for AI/MR, maintain the ______ and avoid increased ______
preload
SVR
risk reduction strategies: place pacers in _______ mode and interrogate
asynchronous
risk reduction strategies: keep ext defib available for AICD and disable if ______ _______
above umbilicus
risk reduction strategies: early utilization of ______ for control of ischemia
IABP
risk reduction strategies: monitoring of ______ if EKG changes are noted/cardiac symptoms present
troponin
IHD, like _____ is present
HTN
______ ______ can recognize IHD
screening tools
whether resolved or not, _____ _____ can result in coronary ischemia during anesthesia
surgical stress
a primary goal is to keep the oxygen supply and delivery ______
nominal
a second goal is to minimize the stimulation of oxygen demanding ____ and ______
events and processes
