Exam II: CV drugs - ACEIs, CCBs, and vasodilators Flashcards
Concerns with Antihypertensives and Anesthesia
Interference with the sympathetic nervous system’s activity resulting in ___ ____, or exaggerated hypotension related to _____, position change, or decreased _____ ____ (pos. pressure ventilation)
orthostatic hypotension
hypovolemia
venous return
Concerns with Antihypertensives and Anesthesia
Possible depletion of _____ stores – minimal response to indirect sympathomimetics
norepinephrine
Concerns with Antihypertensives and Anesthesia
Exaggerated response to direct sympathomimetics – due to no counter-balancing ____ ____.
beta2 activity
Historical perspective
Prior to the mid-1970’s, antihypertensives were withheld prior to surgery due to their ___ ___ nature.
myocardial depressant
Historical perspective
The drugs of the day caused severe ___ ___.
perioperative lability
Historical perspective
Today, we know that beta-blockers may ____ the outcome of patients with hypertension.
improve
Historical perspective
Other than ____, antihypertensive medications* should be continued even on the morning of surgery-fewer alterations in BP and HR, fewer _____.
diuretics
arrhythmias
Beta-adrenergic blockers – negative ___, _____
chronotropic, inotropic
Combined alpha1- and beta-adrenergic blocker (Labetalol)-negative inotropic, chronotropic, vasodilation; _________ as beta-blockers or phentolamine
not as potent
Alpha1-adrenergic blocker (prazosin, phentolamine)-_____
vasodilation
Centrally acting alpha2-adrenergic agonist (clonidine, dexmedetomidine) – decrease _____ outflow
sympathetic
ACEIs MOA:
inhibit the ACE in both the plasma and in the vascular endothelium, thus block the conversion of ____ to ____, thus preventing the vasoconstriction from angiotensin II and the stimulation of the ____,
decreased aldosterone-decreased ____ & ____ retention (however, increased K)
angiotensin I to angiotensin II
SNS
Na and water
ACEIs advantage -
minimal ___ ___ compared to beta-blockers, diuretics
side effects
ACEIs indications -
hypertension (in ____), CHF, mitral ____ (F,F,V), development of CHF (regression of ____)
diabetes
regurgitation
LVH
ACEIs CIs:
patients with ___ ____ ____ (their renal perfusion is highly dependent on angiotensin II)
renal artery stenosis
slide 10 poses question about continuing ACEI therapy. The notes provide summary:
“despite the known hypotensive effect of both ACE inhibitors and ARBs, the 2014 ACC/AHA guidelines on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery recommend ______ this therapy in the _____ period.”
maintaining
perioperative
ACEI Recommendation: _____ ACE inhibitors on the day of surgery or _____ on day before surgery
withhold
discontinue
ACEIs: Hypotension was to be controlled to within __% of baseline with fluid and vasopressors.
30%
Continuation of ACEI to day of surgery:
More intraoperative _____
No difference in ____ consequences
hypotension
adverse
Meta-analysis – both ACEI and ARBs:
Withholding prior to surgery -
____ intraoperative hypotension
___ ____ in mortality or major adverse cardiac event
less
No change
Large cohort prospective study of noncardiac surgery patients:
Continuation of either ACEI and ARBs prior to surgery - Increase in ____ or ___ ____ events
mortality or major adverse
Despite the known hypotensive effect of both ACE inhibitors and ARBs, the 2014 ACC/AHA guidelines on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery state it ___ ___ ___ ___ these drugs until time of surgery.
“is reasonable” to continue
ACE Inhibitors – Side Effects
benefit is _____ SEs, most common are c____, upper resp c____, rhinorrhea, _____ ____ symptoms.
minimal
cough
congestion
allergic-like
(r/t Potentiation of kinins and Inhibition of breakdown of bradykinins)
ACE Inhibitors – Side Effects
______ – potentially life-threatening
Epi 0.3 to 0.5 mL of __:___ dilution*
Angioedema
1:1,000
ACE Inhibitors – Side Effects
Hyperkalemia – due to decreased production of _____ (esp. CHF w/ renal insuff)
aldosterone
ACE Inhibitors – Side Effects
Angioedema may occur _____ after prolonged drug use.
unexpectedly
ACE Inhibitors – Side Effects
Hereditary angioedema is due to __ ____ ____ deficiency
C1 esterase inhibitor
ACE Inhibitors – Side Effects
ACE inhibitor induced is due to increased availability of bradykinin because ____ ____ is blocked.
bradykinin catabolism
How is angioedema treated? (4)
(r/t ACEIs - MARVEL)
Epi (catecholamines, antihistamines, and antifibrinolytics may be ineffective in acute episodes)
Tranexamic acid or aprotinin – inhibits plasmin activation
Icatibant – a synthetic bradykinin receptor antagonist
FFP – 2-4 units – to replace the deficient enzyme
Angiotensin-Converting Enzyme Inhibitors - Captopril (Capoten)
PO dose:
12.5-25 mg PO (TC says not important to know)
Angiotensin-Converting Enzyme Inhibitors - Captopril (Capoten)
Decreased ____ – especially in renal
__, __ not effected
SVR
CO, HR
Angiotensin-Converting Enzyme Inhibitors - Captopril (Capoten)
Baroreceptor sensitivity ____
reduced (HR does not increase with decreased BP)
Angiotensin-Converting Enzyme Inhibitors - Captopril (Capoten)
May cause _____ (related to blocking of aldosterone release)
hyperkalemia
Angiotensin-Converting Enzyme Inhibitors - Captopril (Capoten)
Onset ___ min Duration ___ hours
Onset 15 min Duration 6-10 hours
Angiotensin-Converting Enzyme Inhibitors - Captopril (Capoten)
Cough, upper respiratory congestion, rhinorrhea, and allergic-like symptoms are most common. This is due to the ____ of ____ ____, which normally breaks down bradykinins.
inhibition of peptidyl-dipeptidase activity
Angiotensin-Converting Enzyme Inhibitors - Enalapril (Vasotec)
PO Dose:
20 mg
Angiotensin-Converting Enzyme Inhibitors - Enalapril (Vasotec)
Available in IV ___-___ mg
0.625-1.25 mg
Angiotensin-Converting Enzyme Inhibitors - Enalapril (Vasotec)
Onset approx __ hour; Duration ____ hours
1
18-30
Angiotensin-Converting Enzyme Inhibitors - Enalapril (Vasotec)
Lacks the rash and pruritus side effects of _____; rarely _____ of the face, lips, tongue and glottis; watch for hypotension
captopril
angioedema
Angiotensin-Converting Enzyme Inhibitors - Enalapril (Vasotec)
Not commonly given perioperatively. _____ onset and duration is _____ (compared to vasodilators like nipride and ntg).
Unpredictable
negative
Other ACEIs: (6)
Benazepril (Lotensin)
Fosinopril
Lisinopril (Prinivil, Zestril)
Moexipril
Perindopril
Quinapril (Accupril)
Angiotensin Receptor Blocker - Losartan (Cozaar)
MOA – blocks the binding of angiotensin II to the receptors (type AT1 – found in vascular smooth muscle) to prevent ____ and _____ release
vasoconstriction and aldosterone
Angiotensin Receptor Blocker - Losartan (Cozaar)
Similar effects as ___ ___
ACE inhibitors
Angiotensin Receptor Blocker - Losartan (Cozaar)
Risk of ____ reduction* - 25% (compared to atenolol)
Risk of stroke reduction* - 25% (compared to atenolol)
Angiotensin Receptor Blocker - Losartan (Cozaar)
Dose:
Dose 50 mg
Angiotensin Receptor Blocker - Losartan (Cozaar)
May be combined with ___ ___ or inhibitor of _____** (Entresto)
thiazide diuretic
neprilysin
Angiotensin Receptor Blocker - Losartan (Cozaar)
____ is losartan and hydrochlorothiazide—combined with diuretic.
Hyzaar
Angiotensin Receptor Blocker - Losartan (Cozaar)
Cough due to ____ ____ is significantly less than w ACE inhibitors
bradykinin accumulation
Angiotensin Receptor Blocker - Losartan (Cozaar)
*effectiveness is ___ ___ in black patients (with HTN and LVH) – LIFE study out of New Zealand
not seen
Calcium Channel Blockers - Classifications
_______ - occludes the channel (Verapamil)
_______ - arterial vascular smooth cells (Nifedipine, nicardipine, nimodipine)
_______ - AV node-?MOA (Diltiazem)
Phenylalkylamines
1,4-Dihydropyridines
Benzothiazepines
CCBs - Dihydropyridines
Treat HTN in the ____, ____ ____, and ___-____ patients
elderly, African Americans, and salt-sensitive
CCBs MOA:
Bind to the alpha1 subunit of the ____ ___-____ calcium ion channels
Block calcium entering the cardiac and vascular smooth muscle cells - _____ specific
Reduction of calcium - Fails to ____ ____ - which reduces contraction, ____ depolarization of SA and AV nodal tissue
slow L-type
Arterial
activate myosin
Slows
CCBs MOA:
Calcium ion influx is responsible for the ___ ___ of the cardiac action potential, which is important in the ____/____ ____ in cardiac and vascular smooth muscle and depolarization of the SA and AV nodal tissue
phase 2
excitation/contraction coupling
Calcium Channel Blockers - effects
Negative ____, _____ effects
inotropic, chronotropic
Calcium Channel Blockers - effects
Decreased ___ node activity
SA
Calcium Channel Blockers - effects
Conduction slowed through the ___ node
AV
Calcium Channel Blockers - effects
Vasodilation, decreased ___
BP
Calcium Channel Blockers - effects
Relaxes ___ ___ spasm
Complements ____ (different MOA)
coronary artery
nitrates
CCBs Uses
treatment of coronary artery spasm, unstable ____ ____, chronic stable _____, essential _____
angina pectoris
angina
hypertension
CCBs
Increased risk with dihydropyrimidine derivatives (______)
_____ complications (placebo)
Perioperative bleeding, GI hemorrhage
Development of _____ (compared to beta-blockers, ACE inhibitors)
nifedipine
Cardiovascular
cancer
Calcium Channel Blockers - Verapamil (Calan)
derivative of _____
papaverine
Calcium Channel Blockers - Verapamil (Calan)
_____ contractility
Decreases
Calcium Channel Blockers - Verapamil (Calan)
_____ HR
Decreased
Calcium Channel Blockers - Verapamil (Calan)
Decreased conduction through ___ node
AV
Calcium Channel Blockers - Verapamil (Calan)
Relaxation of vascular _____ ____, coronary arteries
smooth muscle
(Vascular smooth muscle relaxation is more arterial.)
Calcium Channel Blockers - Verapamil (Calan)
Uses-treatment of ___ (AV node), ___
SVT
HTN
Calcium Channel Blockers - Verapamil (Calan)
Dose ___-___ mcg/kg (__-__ mg) IV slowly
75-150
2.5-5
Calcium Channel Blockers - Verapamil (Calan)
Onset __-__ minutes
1-3
Calcium Channel Blockers - Verapamil (Calan)
Oral nearly complete ____ metabolism
hepatic
Calcium Channel Blockers - Verapamil (Calan)
IV ___% renal metabolism, ___% in bile
70%
15%
Calcium Channel Blockers - Verapamil (Calan)
Elimination ½ life __-__ hours
6-12
Calcium Channel Blockers - Verapamil (Calan)
Combination with ___ ___ - has additive myocardial depressant and vasodilation effects, even in normal LV function
volatile anes
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Vasodilation of ____ and ____ _____ (>verapamil)
coronary and peripheral arteries
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
_____ BP
Decreased
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Indirect ____-____ increased HR
baroreceptor-mediated
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
____ decreased contractility, decreased chronotropic, and dromotrophic effects
Directly
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
routes of admin
PO, IV or SL
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Uses – angina, especially coronary artery vasospasm, hypertension emergencies (____/____ -cerebrovascular ischemia, MI, severe hypotension)
CAUTION/STOP
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Dose __-__ mg PO or SL
10-20
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Onset __ min
20
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Metabolism ____ - Elim ½ life: __-__ hours
hepatic
2-5
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Negative effects are due to ___ ____ ____ of BP
too rapid lowering
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Side effects – f____, h____, v_____, hypotension; may cause ____ dysfunction.
Side effects – flushing, headache, vertigo, hypotension; may cause renal dysfunction.
Calcium Channel Blockers - Nifedipine (Adalat, Procardia)-dihydropyridine
Abrupt stop has caused ____ ____ ____
coronary artery vasospasm
Calcium Channel Blockers - Nicardipine (Cardene)
Selective ____ vasodilation - SVR
arterial
Calcium Channel Blockers - Nicardipine (Cardene)
Greatest _____ effects - especially _____ arteries
vasodilating
coronary
Calcium Channel Blockers - Nicardipine (Cardene)
Does not effect the __ ___ or ___ ___, minimal myocardial depressant effects
SA node or AV node
Calcium Channel Blockers - Nicardipine (Cardene)
25 mg in 240 ml solution (0.1 mg/ml)
Titrate – start at __ mg/hr (__ ml/hr), increase by ___ mg/hr every __-___* mins to a max of __ mg/hr
5 mg/hr
50 ml/hr
2.5 mg/hr
5-15 mins
15 mg/hr
Calcium Channel Blockers - Nicardipine (Cardene)
Not compatible with ____ ____
Lactated Ringer’s
Calcium Channel Blockers - Nicardipine (Cardene)
*every __ _____ titration for more rapid reduction; every __ _____ otherwise
5 mins
15 mins
Calcium Channel Blockers - Nicardipine (Cardene)
Contraindicated with advanced ___ ___
aortic stenosis
Calcium Channel Blockers - Clevidipine (Cleviprex)
3rd generation _____
dihydropyridine
Calcium Channel Blockers - Clevidipine (Cleviprex)
____ onset, _____
Rapid onset, titratable
Calcium Channel Blockers - Clevidipine (Cleviprex)
___ emulsion (similar to _____)
Lipid emulsion (similar to propofol)
Calcium Channel Blockers - Clevidipine (Cleviprex)
metabolism:
Metabolism: plasma and tissue esterases (organ independent)
Calcium Channel Blockers - Clevidipine (Cleviprex)
Related to increased _____: maximum administration rate should not exceed ___ ____
triglycerides
32 mg/h
Calcium Channel Blockers - Clevidipine (Cleviprex)
Researchers reached their target intraoperative mean arterial pressure (50-65 mm Hg) within 5 to 10 minutes in a group of adolescents using clevidipine infusion rate of 0.5 to 1 µg/kg/min, titrated by 0.5 to 1 mg/kg/min increments every 2 to 3 minutes. ____ of the patients experienced ____ _____ events that required intervention, and BP measurements returned to baseline within __ to __ _____ of stopping clevidipine infusion.
None
excessive hypotensive
5 to 10 minutes
Calcium Channel Blockers - Nimodipine (Nimotop)
Highly ___ ___ to cross ___ ___ barrier
lipid soluble
blood brain
Calcium Channel Blockers - Nimodipine (Nimotop)
Used to treat vasospasms related to ____ _____
subarachnoid hemorrhage
Calcium Channel Blockers - Nimodipine (Nimotop)
Dose 0.7 mg/kg PO then ___ mg/kg ___ hrs for ___ days
0.35
q4
21
Calcium Channel Blockers - Nimodipine (Nimotop)
If _____ compliance is a concern, an increase in ___ could occur
intracranial
ICP
Calcium Channel Blockers - Diltiazem (Cardizem, Dilacor, Tiazac)
Class
Benzothiazepine
Calcium Channel Blockers - Diltiazem (Cardizem, Dilacor, Tiazac)
Blocks channels in the __ ____
AV node
Calcium Channel Blockers - Diltiazem (Cardizem, Dilacor, Tiazac)
Uses:
Uses - treatment of SVT, angina pectoris
Calcium Channel Blockers - Diltiazem (Cardizem, Dilacor, Tiazac)
Dose ___ mg/kg IV over 2 minutes, may repeat in 15 min if needed
Infusion __ mg/hr
0.25
10
Calcium Channel Blockers - Diltiazem (Cardizem, Dilacor, Tiazac)
Elimination via ___ (60%) and ____ (35%)
bile
urine
Calcium Channel Blockers - Diltiazem (Cardizem, Dilacor, Tiazac)
Elimination ½ time __-__ hours
3-5
Calcium Channel Blockers - Drug interactions
Additive myocardial depression and vasodilation with ___ ____, especially with preexisting ____ ____
volatile anesthetics
LV dysfunction
Calcium Channel Blockers - Drug interactions
Potentiate ___ and ___ ___ ______-_____ drugs like ____ antibiotics (Ca ions are needed to release acetylcholine at the NM junction)
dep and non dep neuromuscular-blocking
mycin
Calcium Channel Blockers - Drug interactions
Increased risk of ___ ____ ____ (inhibition of Na ion movement via Na channels)
local anesthetic toxicity
Calcium Channel Blockers - Drug interactions
Hyperkalemia with K replacement due to ____ of ____ ____ ____ ___
inhibition of K moving into cell
Calcium Channel Blockers - Drug interactions
____ and _____ cause hyperkalemia
Verapamil and dantrolene
Calcium Channel Blockers - Drug interactions
Increase ____ ____ concentration – decreasing its clearance.
digoxin plasma
Vasodilators Indications: (3)
Treat hypertension
Induce controlled hypotension
Encourage LV stroke volume
Vasodilators Effects: (3)
Decrease BP
Decrease SVR (arterial)
Decrease venous return and CO (venodilator)
Nitric Oxide
_____ cause both pulmonary and systemic vasodilation by producing ___ ____ (__).
Nitrovasodilators
nitric oxide (NO)
Nitric Oxide
NO – increases intracellular ____ causing smooth muscle relaxation
Results ultimately from decreased ____ ____ (similar to the effect of cAMP from beta2 stimulation)
cGMP
intracellular calcium
Nitric Oxide
Can be inhaled in the gaseous state to cause ___ ___ specifically
pulmonary vasodilation
Nitric Oxide
Increased cGMP can potentially coexist with _____ due to stimulation of ___ receptors.
bronchoconstriction
M3
Nitric Oxide
____ ____ ____ ____ – previous name for NO
Endothelial derived relaxing factor (EDRF)
Nitric Oxide
Administration of NO affects ____ specifically – it doesn’t affect SVR due to rapid ____ by ____
PVR
uptake by hemoglobin
Nitric Oxide - endogenous CV effects
Release of NO from endothelial cells due to ___ ___ and ____ ____ ____
shear stress and pulsatile arterial flow
Nitric Oxide - endogenous CV effects
Regulates ____ and ____ – baseline
SVR and PVR
Nitric Oxide - endogenous CV effects
Impacts distribution of ____ ____
cardiac output
Nitric Oxide - endogenous CV effects
Autoregulation – increased ___ _____ with decreased ______
NO production
oxygenation
Nitric Oxide - endogenous CV effects
____ produce more NO than ____ (IMA remains patent longer than saphenous vein grafts)
Arteries
veins
Nitric Oxide - endogenous pulm effects
Broncho_____
Bronchodilation
Nitric Oxide - endogenous pulm effects
Selective dilation of vessels to ___ ____
ventilated alveoli
Nitric Oxide - endogenous platelet effect
Inhibits plt activation, aggregation, and adhesion (_____)
antithrombotic
Nitric Oxide - endogenous nervous system effects
Neurotransmitter in ____, ___ ____ and peripheral nervous system
brain, spinal cord,
Nitric Oxide - endogenous nervous system effects
May be involved in _____ and anesthetic effects
antinociception
Nitric Oxide - endogenous
Produce relaxation of ___ ___ and ___ tract
smooth muscle
GI
Nitric Oxide - endogenous immune response
Produced in response to activation of ______
macrophages
Nitric Oxide - endogenous immune response
Can damage b____, f____, and p_____
bacteria, fungi, and protozoa
Pathophysiologic effects related to NO
Essential hypertension - _____ NO release
Sepsis shock – _____ NO release
Atherosclerosis – _____ NO – platelet aggregation, vasoconstriction
Cirrhosis – _____ production of NO
decreased
excessive
decreased
excessive
Anesthetic Effects on NO
Involved in the _____ neurotransmission
excitatory
Anesthetic Effects on NO
Anesthetics cause _____ of formation of NO to _____ excitatory neurotransmission and ____ GABA inhibitory transmission
suppression
decrease
enhance
Anesthetic Effects on NO
Administration of NO synthase inhibitors have a ___-___ ____ in MAC
dose-dependent reduction
Uses of NO
Inhaled form to treat ______ ______ (use in any other than ______ is “off label” use
pulmonary hypertension
neonates
Uses of NO
In neonates, its use has decreased the use of _____
ECMO
Sodium Nitroprusside (SNP, Nipride)
___-___, arterial and venous vascular smooth muscle relaxant
Direct-acting
Sodium Nitroprusside (SNP, Nipride)
Vasodilation of ____ and ____
arterial and venous
Sodium Nitroprusside (SNP, Nipride)
Sodium Nitroprusside (SNP, Nipride)
onset
60-90 seconds
Sodium Nitroprusside (SNP, Nipride)
Duration short requiring ___, ____
infusion, titration
Sodium Nitroprusside (SNP, Nipride)
Careful monitoring, ___ ___
infusion device
Sodium Nitroprusside (SNP, Nipride)
Dose ___-___ mcg/kg/min – up to 5 mcg/kg/min (body can handle only __ ____ continuous)
0.25-1
2 mcg/kg/min
Sodium Nitroprusside (SNP, Nipride)
MOA – reacts with ____ to _____ _____ and releases cyanide and nitric oxide (NO). NO causes the _____.
hemoglobin to form methemoglobin
vasodilation
Sodium Nitroprusside (SNP, Nipride)
Nipride is 44% cyanide (CN-) and during metabolism ___ ____ ____ are released making cyanide toxicity possible-causing ____ ____, _____ metabolism, and ____ acidosis
five cyanide ions
tissue anoxia, anaerobic metabolism, and lactic acidosis.
Sodium Nitroprusside (SNP, Nipride) - who is susceptible to CN- toxicity
Receiving infusion of ______
Children or young adults – baroreceptor reflexes cause ____ of SNS –require ___ ___
Pregnancy - ____ cyanide toxicity
> 2 mcg/kg/min
stimulation
larger dose
fetal
Sodium Nitroprusside (SNP, Nipride) - CN- toxicity S&S:
Unresponsive to previously ____ ___ of SNP
Increased MvO2 – inability of tissues to ___ ___
Metabolic ____
CNS dysfunction, ____
therapeutic doses
use oxygen
acidosis
seizures
Sodium Nitroprusside (SNP, Nipride) - treatment of CN- toxicity: (4)
Stop infusion
100% oxygen
Sodium bicarbonate to correct met acidosis
Sodium thiosulfate to be a sulfur donor to convert cyanide to thiocyanate
Sodium Nitroprusside (SNP, Nipride)
Nipride must be protected from the light to prevent breakdown into ____. Light-protected solutions are safe for ___ ____.
cyanide
24 hours
Sodium Nitroprusside (SNP, Nipride)
CV effects - ____ arterial and venous vasodilation
direct
Sodium Nitroprusside (SNP, Nipride)
Decreased ___, ___, Indirect increase in HR and contractility, May have increased ___
BP, SVR
CO
Sodium Nitroprusside (SNP, Nipride)
Coronary artery vasodilation which creates ___ ___ from ischemic areas.
coronary steal
Sodium Nitroprusside (SNP, Nipride)
Decrease in ____ pressure
diastolic
Sodium Nitroprusside (SNP, Nipride) - CNS
Increased ____ blood flow
Increased ____ blood volume
cerebral
cerebral
Sodium Nitroprusside (SNP, Nipride) - CNS
ICP increases are ____ if MAP decreases less than 30%; if >30% decrease in MAP, the ICP ____ to ____ levels.
maximal
returns to awake
Sodium Nitroprusside (SNP, Nipride)
CPP = ____-____
CPP = MAP - ICP
Sodium Nitroprusside (SNP, Nipride) - CNS
To prevent the increase in ICP, infuse the SNP to slowly lower BP over ___ _____ along with ____ and _____
5 minutes
hyperoxia
hypocarbia
Sodium Nitroprusside (SNP, Nipride) - CNS
Once the dura is open, ICP problems are ___ ___ ____.
not a problem
Sodium Nitroprusside (SNP, Nipride) - CNS contraindications
Patients with increased ___ and inadequate cerebral ____ ___, and patients with ___ ___ stenosis
ICP
blood flow
carotid artery
Sodium Nitroprusside (SNP, Nipride) - pulm effects
decrease in the _____, alteration of ____ ____ ____
PaO2
hypoxic pulmonary vasoconstriction
Sodium Nitroprusside (SNP, Nipride) - pulm effects
Bigger problem with ____ lungs
healthy
Sodium Nitroprusside (SNP, Nipride) - pulm effects
___ ____ develop vascular changes that prevent this effect
COPD lungs
Sodium Nitroprusside (SNP, Nipride) - pulm effects
Treat: add ____
PEEP
Sodium Nitroprusside (SNP, Nipride) - pulm effects
Inhibits platelet aggregation (___mcg/kg/min)
No ____ ____-bleeding not increased
> 3
clinical significance
Sodium Nitroprusside (SNP, Nipride) - clinical uses
Deliberate _____
Most likely to maintain ____ perfusion
Initial rate – __ to ___ mcg/kg/min
Should not exceed ___ mcg/kg/min
Combined with other agents to min. risk of CN- tox
hypotension
cerebral
0.3 to 0.5
2
Sodium Nitroprusside (SNP, Nipride) - clinical uses
Hypertensive emergencies
_____ initial treatment – effective ___ ____ the cause – onset, titration, quick offset
Temporary
no matter
Sodium Nitroprusside (SNP, Nipride) - clinical uses
Cardiac disease – decreased ____
MR, AR, CHF, MI with LV failure (may also need ____)
afterload
inotrope
Sodium Nitroprusside (SNP, Nipride) - clinical uses
____ surgery
Treat HTN related to ___-___
? spinal cord ischemia – distal _____
Aortic
cross-clamp
hypotension
Sodium Nitroprusside (SNP, Nipride) - clinical uses
Cardiac surgery
_____ period to cause vasodilation to distribute warmth to periphery
Treat pulmonary hypertension after ___ ____ (pulmonary vasodilator)
Rewarming
valve replacement
Vasodilators - Nitroglycerin
____ nitrate
Organic
Vasodilators - Nitroglycerin
Dilates venous side except, at ____ doses, it will relax ___ ___ ___
elevated
arterial smooth muscle
Vasodilators - Nitroglycerin
MOA – produces ___ ___ (__) which causes peripheral vasodilation
nitric oxide (NO)
Vasodilators - Nitroglycerin
Sublingual – onset __ ____
4 minutes
Vasodilators - Nitroglycerin
Transdermal – sustained protection from ___
MI
Vasodilators - Nitroglycerin
Infusion requires special ___ and ___ ____ to prevent absorption into the plastic
tubing and glass bottles
Vasodilators - Nitroglycerin
Elimination ½ life – 1.5 minutes requires ____
infusion
Vasodilators - Nitroglycerin
May cause the production of _____ when the nitrite metabolite oxidizes the ____ ion in hemoglobin
methemoglobin
ferrous
Vasodilators - Nitroglycerin
Treatment: ___ ___ 1-2 mg/kg IV over 5 minutes to convert back to hemoglobin
methylene blue
Vasodilators - Nitroglycerin CV effects
Venous ____ (up to 2 mcg/kg/min)
Decreased venous return, ____, ____
CO ____ (in normal heart with no CHF; if patient in heart failure, the CO is improved, and pulmonary congestion is relieved)
dilation
LVEDP, RVEDP
decreased
Vasodilators - Nitroglycerin CV effects
Decreased ___ (related more to volume than SNP)
Decreased ___, coronary blood flow
BP
DBP
Vasodilators - Nitroglycerin CV effects
Dilates larger conductance vessels of the coronary circulation – provides better blood flow to ____ ___
Relaxes ____ vessels
ischemic areas
pulmonary
Vasodilators - Nitroglycerin CV effects
Baroreceptor-reflex ____, increased ____ effect (increased demand, decrease supply)
tachycardia
inotropic
Vasodilators - Nitroglycerin - smooth muscle effects
Relaxes ____ smooth muscle
Relaxes biliary tract smooth muscle (___ of ___)
Relaxes ____ muscles
Relaxes uterine and ureteral smooth muscles
bronchial
sphincter of Oddi
esophageal
Vasodilators - Nitroglycerin - CNS effects
_____ vasodilation
Inhibition of ___ ____
Cerebral
platelet aggregation
Vasodilators - Nitroglycerin - clinical uses
____ ____ - decrease myocardial oxygen demand and vasodilate coronaries to ischemic areas (decrease size of MI-not SNP)
Angina pectoris
Vasodilators - Nitroglycerin - clinical uses
Cardiac failure – decrease ____ and relieve pulmonary ____
preload
edema
Vasodilators - Nitroglycerin - clinical uses
Acute hypertension – maternal patient during C-section with __ ____ on fetus
no effects
Vasodilators - Nitroglycerin - clinical uses
Deliberate hypotension – less potent than SNP; decrease in diastolic is less than SNP; ____ ____ has a bigger effect
intravascular volume
Vasodilators - Isosorbide dinitrate
Oral nitrate – prophylaxis of ____ ____
angina pectoris
Vasodilators - Isosorbide dinitrate
Prolonged _____ effect, increased exercise tolerance up to __ ___
antianginal
6 hours
Vasodilators - Isosorbide dinitrate
Vasodilation of venous circulation and dilation of coronary arteries to ___ ___ ___ to ischemic areas
redirect blood flow
Vasodilators - Isosorbide dinitrate
Given preop to ____ patients
CABG
Vasodilators - Hydralazine (Apresoline)
___ ___ of arterial side, some venous
Direct dilation
Vasodilators - Hydralazine (Apresoline)
Vasodilates (5) things
coronary, cerebral, renal, and splanchnic, pulmonary vessels
Vasodilators - Hydralazine (Apresoline)
MOA – interference with ____ ion transport
calcium
Vasodilators - Hydralazine (Apresoline)
Decreases ____ more than ____ pressure
diastolic
systolic
Vasodilators - Hydralazine (Apresoline)
Increases in HR (baroreceptor and direct), SV, CO (can cause MI, prevented with ___-___)
beta-blocker
Vasodilators - Hydralazine (Apresoline)
Onset 10 to 20 minutes (_____)
Duration 2 to 4 hours (_____)
Dose 10 to 20 mg
prolonged
unpredictable
Vasodilators - Hydralazine (Apresoline)
Mostly ____ metabolism
hepatic
Vasodilators - Hydralazine (Apresoline)
Side effects – ___-___ ____, peripheral neuropathies, vertigo, diaphoresis, nausea, tachycardia – uncommon in ____ use
Lupus-like syndrome
intermittent
Vasodilators - Trimethaphan
Ganglionic blocker – blocks ____ nervous system reflexes
autonomic
Vasodilators - Trimethaphan
Vasodilation of ___ ___ vessels
Decreases CO, ___
venous capacitance
SVR
Vasodilators - Trimethaphan
Blocks receptors for ____
acetylcholine
Vasodilators - Trimethaphan
May have ____ that offsets the benefit of decreased BP
tachycardia
Vasodilators - Trimethaphan
Historical use in ____ ____
deliberate hypotension
Vasodilators - Adenosine
______ _____ in all cells – maintain the balance of oxygen supply and demand of the heart and other organs
Endogenous nucleoside
Vasodilators - Adenosine - Effects
Dilation of coronary arteries (___ possible)
Negative ____
steal
chronotropic
Vasodilators - Adenosine
MOA- stimulation of __ ____ in supraventricular cells to hyperpolarize atrial cells and slowing of SA node
Can also stimulate release of ___ from endothelial cells
K+ channels
NO
Vasodilators - Adenosine - Uses
SVT – paroxysmal SVT and narrow complex tachycardia (not atrial fib or v. tach)
Dose _________
Can repeat within ___ ____
Elimination ½ life ___-___ ____
Dose 6 mg IV, then 12 mg, then 18 mg*
Can repeat within 60 seconds
Elimination ½ life 0.6-1.5 seconds
Vasodilators - Adenosine
Deliberate _____
____ responsiveness, onset and recovery
Decreased SVR, increased HR*, coronary flow increased**, cardiac filling pressures unchanged
____ mcg/kg/min – no _____
hypotension
Rapid
220
tachyphylaxis
“Adenosine infusion evokes a receptor-specific sympatho-excitatory reflex in humans that overrides its ___ ___ ___ effect.”
direct negative chronotropic
Principle Adenosine effects - A1 (4)
Slowing of the rhythm Negative inotropic effects
Vasoconstriction
Bronchoconstriction
Sedation Anticonvulsive effectDecrease of neurotransmitter release
Principle Adenosine effects - A2 (5)
Vasodilation
Bronchodilation
Complex stimulant effects
Increase of neurotransmitter release
Platelet aggregation inhibition
A1 receptors – located in ______ (more in atrial membranes than ventricular) – produce negative chronotropic, dromotropic and inotropic effects. The activation of the A1 receptors inhibits ____ ____, decreases the concentration of intracellular cAMP and induces opening of potassium channels, which indirectly ____ ____ ____ into the cell.
cardiomyocytes
adenyl cyclase
reduces calcium penetration
A2 receptors – in endothelial and vascular smooth muscle – produce coronary artery vasodilation and vascular smooth muscle relaxation -The stimulation of the A2 receptors has an opposite effect, it activates ____ ____.
adenyl cyclase.
Adenosine - Adverse reactions (seen in ___ of ____):
Most common: ____ ____, ___ pain (awake patient), and dyspnea – duration averages 50 seconds
1/3 of patients
facial flushing
chest
Adenosine - If brady arrhythmias persist, can treat with _____ – antagonizes receptor. ______ will be ineffective
aminophylline
Anticholinergics