CV Pharmacology Final Exam Flashcards
Describe pericardial restraint.
A change in volume or pressure on one side of the heart can influence pressure and volume on the other side.
Name 3 symptoms of acute pericarditis.
- chest pain
- pericardial friction rub
- ECG changes
- deep insp. worsens pain
- sitting forward relives pain
An acute influx of as little as _____ of fluid into the pericardium can produce symptomatic cardiac tamponade.
100 ml
Name 2 signs that occur during the respiratory cycle consistent with cardiac tamponade that signals ventricular dysynchrony.
- Kussmauls sign(distention of jugular veins)
2. Pulsus paradoxus( decrease in SBP > 10 mmHg during insp.)
In contrast to skeletal muscle, cardiac muscle requires _____ to contract.
calcium
Describe the Frank-Starling Law of the heart.
The ability of the heart to change its force of contraction and therefore stroke volume in response to changes in venous return(^venous return -> ^ventricular filling -> ^preload)
Name the contractile unit of the cardiac myocyte, consisting of I and A bands.
Sarcomere
Which protein troponin produces the conformational change exposing the specific myosin binding site on actin?
Calcium -> troponin C
Which semilunar valve is often damaged by high pressure _____? Which AV valve is subject to abuse d/t high pressure?
- Aortic
- Mitral
Which main coronary artery supplies the AV node in 90% of the population, and the SA node in 60% of the population?
Right main coronary artery
What defines the time available for coronary vascular perfusion?
Diastole
What is the equations for coronary perfusion pressure(CPP)?
CPP=DBP - PCWP
What is the most potent endogenous vasodilator?
Adenosine
Does Nitric Oxide case (vasodilation or vasoconstriction), and does it (inhibit or promote) platelet aggregation and adhesion?
- vasodilation
- inhibits
Pressure volume loops are 2D plots on continuous pressure vs. volume in the RV or LV?
LV
What is the “normal” CVP?
2 - 8 mmHg
What medications should be used for a Tamponade induction?
- ketamine(increases HR, contractility and SVR)
- BZD
- fentanyl
- careful titration of agent
REMEBER: THE COMBO OF VASODILATION AND MYOCARDIAL DEPRESSION FROM THE ANESTHETIC, IN ADDITOIN TO DECREASED VENOUS RETURN FROM PPV CAN PRODUCE LIFE-THREATENING HYPOTENSION.
What two structures secrete lubricating fluid into the parricidal space?
- Parietal pericardium
2. Visceral pericardium
If perfusion pressure falls by ____% or below the physiological pressure limits, the auto regulatory mechanisms begin to fail and blood flow fails
> 30%
When damage to the endothelium occurs, it produces no ______ and less _____.
- nitric oxide
- prostacyclin
What is the most ominous sign of CAD?
USA that occurs during rest is the most ominous sign of CAD. USA is poorly controlled by medications at this point and carries a significant risk of MI(Valley note)
“Critical stenosis” is a ____% decrease in diameter of a large distributing artery.
75%
What identifies ischemia intraoperatively?(Valley questions)
ST segment depression of > than 1 mm provides evidence of ischemia
The most important factor and primary determinant of myocardial O2 consumption is?
HR
What is the most important interventions to prevent or minimize ischemia?
avoid tachycardia
Cardiac pump function is affected by the SNS and the PNS in what 3 ways?
- changing the strength of contraction
- changing the heart rate
- modulation of coronary blood flow
What part of the SNS increases chronotropy and isotropy(cardiac accelerator fibers)?
T1-T4
What are the cardiovascular reflexes of a Valsalva maneuver?
decreased HR, contractility, vasodilation
What are the cardiovascular reflexes of a Baroreceptor reflex?
decreased HR, contractility, vasodilation
What are the cardiovascular reflexes of a Oculocardiac reflex?
bradycardia, systole, dysrhythmias, hypotension
What are the cardiovascular reflexes of a Celiac reflex?
bradycardia, hypotension, apnea
What are the cardiovascular reflexes of a Bainbridge reflex?
increased HR, decreased BP, decreased SVR, diuresis
What are the cardiovascular reflexes of a Cushing reflex?
SNS resulting in hypertension
What are the cardiovascular reflexes of a Chemoreceptor reflex?
increased respiratory drive, increased BP
The only organ innervated by sympathetic preganglionic neurons is the ___ ___.
Adrenal Medulla
Postganglionic nerves release ___ as a NT and are ___.
- norepinephrine
- adrenergic
Preganglionic nerves release ___ as a NT and are ___.
- acetylcholine
- cholinergic
Stimulation of the AV node is from:
a. sympathetic
b. parasympathetic
c. both a and b
d. only sympathetic
c. both a and b
Stimulation of the SA node is from:
a. sympathetic
b. parasympathetic
c. both a and b
d. only sympathetic
c. both a and b
Ephedrine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
d. Indirect acting sympathomimetics
Labetolol:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
b. Beta-adrenergic antagonists
Epinephrine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
c. Direct acting sympathomimetics
Cocaine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
a. Catecholamine uptake inhibitors
Phenylephrine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
c. Direct acting sympathomimetics
Esmolol:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
b. Beta-adrenergic antagonists
Dopamine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
c. Direct acting sympathomimetics
Phentolamine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
e. Alpha-adrenergic antagonist
Norepinephrine:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
c. Direct acting sympathomimetics
Tricyclic Antidepressants:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
a. Catecholamine uptake inhibitors
Metoprolol:
a. Catecholamine uptake inhibitors
b. Beta-adrenergic antagonists
c. Direct acting sympathomimetics
d. Indirect acting sympathomimetics
e. Alpha-adrenergic antagonist
b. Beta-adrenergic antagonists
___ is the NT employed at all preganglionic sites in the SNS and PNS junctions.
Acetylcholine
Epinephrine and Norepinephrine are released when SNS stimulation of the ___ ___ occurs.
Adrenal Medulla
Respond to acetylcholine:
a. Adrenergic
b. Cholinergic
b. cholinergic
Dopaminergic receptors:
a. Adrenergic
b. Cholinergic
a. adrenergic
Beta receptors:
a. Adrenergic
b. Cholinergic
a. adrenergic
Nicotinic receptors:
a. Adrenergic
b. Cholinergic
b. cholinergic
Respond to NE and E:
a. Adrenergic
b. Cholinergic
a. adrenergic
Alpha receptors:
a. Adrenergic
b. Cholinergic
a. adrenergic
Muscarinic receptors:
a. Adrenergic
b. Cholinergic
b. cholinergic
Increased HR:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
c. Beta 1 receptors
Decreased HR:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
b. muscarinic receptors
Cardiac arteriole dilation:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
a. Beta 2 receptors
Constriction of veins:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
d. Alpha 1 receptors
Constriction of arterioles:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
d. Alpha 1 receptors
Increased cardiac conduction:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
c. Beta 1 receptors
Constriction of bronchi:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
b. muscarinic receptors
Release of Epinephrine from adrenal medulla:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
e. nicotinic receptors
Inhibition of NT release:
a. Beta 2 receptors
b. Muscarinic receptors
c. Beta 1 receptors
d. Alpha 1 receptors
e. Nicotinic receptors
f. Alpha 2 receptors
f. Alpha 2 receptors
Duration of action of Milrinone:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
b. 1/2 life 2 hours
Duration of action of Phenylephrine:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
g. 5-10 minutes
Duration of action of Calcium:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
a. 15 minutes
Duration of action of Dobutamine:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
c. 2-5 minutes
Duration of Ephedrine:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
f. up to 1 hour
Duration of Norepinephrine:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
d. 1-2 minutes
Duration of Vasopressin:
a. 15 minutes
b. 1/2 L 2 hours
c. 2-5 minutes
d. 1-2 minutes
e. 2-8 hours
f. up to 1 hour
g. 5-10 minutes
e. 2-8 hours
Name one drug used as a first line agent in PEA and cardiac arrest/a-systole.
Epinephrine
Name any two sympathomimetic amines.
- Phenylephrine
- Ephedrine
Describe why Phenylephrine is considered useful in patients with ischemic heart disease.
- does not increase HR
- has no inotropic or chronotropic effects
In your own words, describe any effect on the heart when a patient is effectively beta blocked, and you use Phenylephrine to assist in BP control.
- increases after load thereby increasing work load on the heart
- coronary artery constriction
- bradycardia
- decreased stroke volume
- increased PVR
Why is there a high risk of malignant hypertension when Ephedrine is used with MAOI’s?
MAOI’s prevent the breakdown of norepinephrine in the synaptic cleft.
Dopamine:
INDICATIONS FOR USE
a. hypotension with low HR and low CO
b. alternative to Epi in VF
c. good 1st line inotrope, for low CO or low SVR
d. may impose ischemic burden prior to revascularization
e. used in vasoplegia syndrome
f. prophylactic use with massive blood transfusion
c. good 1st line inotrope, for low CO or low SVR
Ephedrine:
INDICATIONS FOR USE
a. hypotension with low HR and low CO
b. alternative to Epi in VF
c. good 1st line inotrope, for low CO or low SVR
d. may impose ischemic burden prior to revascularization
e. used in vasoplegia syndrome
f. prophylactic use with massive blood transfusion
a. hypotension with low HR and low CO
Calcium Chloride:
INDICATIONS FOR USE
a. hypotension with low HR and low CO
b. alternative to Epi in VF
c. good 1st line inotrope, for low CO or low SVR
d. may impose ischemic burden prior to revascularization
e. used in vasoplegia syndrome
f. prophylactic use with massive blood transfusion
f. prophylactic use with massive blood transfusion
Methylene Blue:
INDICATIONS FOR USE
a. hypotension with low HR and low CO
b. alternative to Epi in VF
c. good 1st line inotrope, for low CO or low SVR
d. may impose ischemic burden prior to revascularization
e. used in vasoplegia syndrome
f. prophylactic use with massive blood transfusion
e. used in vasoplegia syndrome
Vasopressin:
INDICATIONS FOR USE
a. hypotension with low HR and low CO
b. alternative to Epi in VF
c. good 1st line inotrope, for low CO or low SVR
d. may impose ischemic burden prior to revascularization
e. used in vasoplegia syndrome
f. prophylactic use with massive blood transfusion
b. alternative to epinephrine in VF
Norepinephrine:
INDICATIONS FOR USE
a. hypotension with low HR and low CO
b. alternative to Epi in VF
c. good 1st line inotrope, for low CO or low SVR
d. may impose ischemic burden prior to revascularization
e. used in vasoplegia syndrome
f. prophylactic use with massive blood transfusion
d. may impose ischemic burden prior revascularization
Your healthy ASA I patient is experiencing hypotension around the time of indication. You are aware that the CO is normal, but the HR is consistently in the 40’s and 50’s. What drug would you use to increase the BP? Why?
- ephedrine
- use for hypotension due to low SVR or low CO….especially is HR is low.
Calculate the CO for a patient whose SV - 79 mL and HR = 71 mL. What is the formula for CO?
- 5609 mL/min
- CO= SVxHR
How many mcg/mL of neosynephrine are in a 1:250,000 solution?
4 mcg/mL
List 3 beneficial effects of Nitroglycerine in the patients with CAD.
- enters smooth muscles and is converted to NO(nitric oxide)
- smooth muscle relaxation results in vasodilation
- enhances myocardial oxygen delivery and reduces demand
- low doses—>venodilation; high doses—>arterial smooth muscle dilation
Discuss how nitroglycerin may be better suited for pulmonary hypertension than other more potent arterial vasodilators.
- vasodilation of pulmonary arteries and veins(more than systemic)
- inhibits HPV
- decreases pulmonary artery and right atrial pressures
- decreases PCWP and PVR
List 4 beneficial effects and 4 adverse effects of beta blockade in patients with ischemic heart disease.
BENEFICIAL EFFECTS: -reduction in myocardial oxygen consumption -improved coronary blood flow -prolonged diastole -increased flow to ischemic area ADVERSE EFFECTS: -CHF--->potentiated by anesthetics -bronchospasm -hypoglycemia -withdrawal associated with enhanced adrenergic activity(increased HR, HTN, myocardial ischemia)
Discuss perioperative recommendations for perioperative beta blockade in patients with CAD.
- continue BB throughout perioperative period
- BB should have been initiated within 24 hours of operation
- goal of perioperative beta blockade is HR 65-80
Compare Diltiazem and Verapamil to Nicardipine and Nifedipine in regard to clinical effects.
- Diltiazem and Verapamil have local anesthetic action which may potentiate meds(NEGATIVE INOTROPIC EFFECT)
- Nicardipine and Nifedipine primary action on arterioles is VASODILATION
- Diltiazem, Verapamil and Nicardipine have coronary vasodilation and suppression of SA node
- Nifedipine may cause reflex tachycardia
- Verapamil is less potent but significant myocardial depression, negative chronotropic effect on SA node, negative inotropic effect on the heart muscle, and severely depresses AV node
- Diltiazem is less potent vasodilator, less myocardial depression, slows AV conduction
- Nicardipine has the greatest degree of vasodilation, docent decrease myocardial contractility
List 3 potential adverse effects associated with CCB’s during general anesthesia.
- systemic hypotension
- heart failure
- asystole
- AV block
- peripheral edema
Discuss conventional thought on serum potassium and general anesthesia in patients on diuretics AND describe how fast you would infuse a KCL 20 meq IV bolus.
K
List 2 hemodynamic concerns associated with ACEI and ARB’s during general anesthesia.
- normal response to surgical stimulation may be attenuated
- concomitant use of diuretic, worsens the hypotension
- renin response to hemorrhage or hypotension will be impaired
List 4 classes of drugs used to treat heart failure that may interact with anesthesia agents.
- ACEI
- ARBs
- CCB
- Beta blockers
You obtain a vial of phenylephrine 1mg/ml. If you mix that 1 ml in a 50ml bag of saline, what is the concentration of the Phenylephrine in the bag?
(1mg/ml)/50mg=0.02 mg/ml—>20mcg/ml
What is the “triple therapy” that is the mainstay of pharmacologic treatment of heart failure?
- ACEI
- BB
- diuretics
How do circulating catecholamine levels correlate with the severity of heart failure?
- response is diminished secondary to down regulation
- circulating catecholamine levels increase in direct proportion to the severity of LV dysfunction
Are norepinephrine levels increased or decreased in patients with heart failure?
increased
If a patient is sensitive or allergic to sulfonamides, which diuretic is given initially?
Edecrin
What electrolyte abnormalities(considering Na, K, Mag) are often present in patients with heart failure?
decreased Na, K, and Mag
What are 3 compensatory mechanisms in heart failure?
- increased preload and sympathetic tone
- activation of the renin-angiotensin system
- ventricular dilation(enlargement)
- increased HR
Calculate the EF for a patient with an EDV of 144 and an ESV of 67.
EF=EDV-ESV/EDV(100)
EF=144-67/144(100)
EF=77/144(100)
EF=53%
Calculate the SV when a patient has EDV=142 and ESV=63.
SV=EDV-ESV
SV=142-63
SV=79
Calculate the SVR for a patient in whom the MAP=75 mmHg, CVP=9 mmHg and CO=4.6 L/min.
SVR=80(MAP-CVP)/CO
SVR=80(75-9)/4.6 L/min
SVR=1148
Describe any 3 treatments for a patient in ADHF.
- diuretics
- anxiolytics
- nitrates
- vasodilation/load reduction of LA pressure
- subsequent sympathomimetic interpose and inotropic dilators
- oxygen
- improve symptoms
When using an IABP, what does blood in the balloon line usually indicate?
- sign of rupture somewhere and requires immediate attention
- your balloon isn’t working
- helium can’t expand balloon
- you have lost your augmentation
As a rule, augmented diastolic pressure should be higher or lower than assisted systolic pressure?
higher
Name a vasopressor that increases MvO2?
dobutamine, epinephrine, norepinephrine
Explain 1:1 counts pulsation.
assist every beat
What is the safest trigger to use when transporting a patient post-op to the ICU who is 100% AV paced?
The safest trigger to use is the systolic pressure because the pacer isn’t reliable because the patient could be in PEA. Always have a SpO2 monitor.
During separation from CPB with an orthotropic heart transplant, name 2 benefits of Isuprel.
helps keep HR 100-120 and helps with pulmonary vasodilation
Name 3 signs and symptoms of RV failure after orthotropic heart transplant.
- CO and PCWP low
- CVP>15
- PAP>40
Why are two P waves often present during orthotropic heart transplant?
original atrial tissue produces nonconducting P waves and graft atrium produces normally conducted P waves.
A patient who has had a heart transplant
Resting HR of denervated heart is about 90-100 bp due to absence of parasympathetic tone at SA node.
During anesthesia care for a patient who had a heart transplant
- Any changes in HR depends on systemic catecholamine’s traveling in circulatory system from adrenal gland. Can take up to 10 minutes for systemic catecholamine’s to circulate to SA node, and up to 1 hour to return to normal. Expect a delayed response to DL, ETT, Exercise and stress.
- Baroreceptor response to exogenous catecholamine’s is also absent.
Which is considered to be “denervated” heart? Donor heart or native heart?
donor heart
Drugs that act through the ANS are effective or ineffective in altering contractility and HR in a donor heart?
ineffective
Name 5 direct acting drugs that are effective in altering HR and contractility in a donor heart.
- Verapamil
- Digoxin
- Isuprel
- Norepinephrine
- Phenylephrine
Name 3 indirect acting drugs that are ineffective in altering HR and contractility in a donor heart.
- atropine
- fentanyl
- pancuronium
Neostigmine + patient s/p heart transplant = ?
asystole
Name a potent beta agonist that you should have averrable as a rescue agent.
isuprel
In patients who are post cardiac transplant, there are often issue with cross-matching blood products for subsequent surgical procedures. Name 3 interventions that a CRNA could perform to assist in preventing these issues.
- notify blood bank early of procedure and patient
- use irradiated
- Leukocyte-depleted
- CMV negative blood
- Use WBC filters in blood tubing line
What drug is given prior to cross-clamp release when giving anesthesia for cardiac transplant?
Methylprednisolone
Hyper-acute rejection may occur in the first ___ after heart transplant?
24 hours
Name 4 characteristics of transplant rejection.
- myocardial dysfunction
- dysrhythmias
- atherosclerosis of coronaries
- decreased exercise tolerance
Compare cardiac action potentials for fast and slow potentials.
FAST: occur in the His-Perkinje system and atrial and ventricle muscle
- conduct impulse and cause contraction
- cardiac action potential -90mV
SLOW: occur in cells of SA node and AV node, 3 features of importance
- depolarization is slow and mediated by calcium influx
- conduction is slow(i.e. AV node)
- spontaneous phase 4 depolarization in SA node determines HR(cardiac AP -60 mV)
List 3 anesthetic agents/adjuvants associated with QT interval prolongation.
- local anesthetics
- ondansetron
- neostigmine
- droperidol
Identify the inotrope least associated with heart rhythm disturbances.
Milrinone(increases isotropy without affecting rhythm)
Identify the dose of epinephrine and dobutamine associated with significant tachycardias.
Epinephrine > 2 mcg/min
Dobutamine > 5 mcg/kg/min
Describe toxic effects associated with amiodarone.
Class III toxicity:
- QT prolongation
- Torsade de Pointe
- Pulmonary toxicity and ARDS
- Bradycardia due to beta blockade
- liver failure
- hypotension(bretyllium)
Identify which class of drugs is considered most effective against supra ventricular dysrhythmias.
Class IV (CCB)
- diltiazem
- verapamil
List doses for lidocaine, procainamide, amiodarone, diltiazem and adenosine.
- lidocaine 1mg/kg(bolus) 2-4mg/min(infusion)
- amiodarone 150mg(bolus) 1mg/kg(infusion)
- diltiazem 2-20mg(bolus) 5-15mg/hr
- adenosine 6mg then 12mg(bolus)
Compare dysrhythmic potential of succinylcholine, vecuronium and rocuronium.
Succs: Active muscarinic and nicotinic receptors cause tachycardia, bradycardia, PVCs, heart block and systole
Vec: decreased automatic causes bradycardia(nodal rhythm) when used with high-dose opioids and maintenance beta blockers
Roc: activate muscarinic receptors causing increases HR/tachycardia especially with concomitant use of anticholinergics
Compare dysrhythmic potential with propofol, volatile agents, dexmedetomidine and ketamine.
PROPOFOL: -few dysrhythmic potential and SE
Volatile agents:
-NITROUS AND SEVO: few dysrhythmic potential and SE
-ISO: causes dysrhythmias in 2.5% of all patients
-DES: increases HR in some circumstances
DEXMEDETOMIDINE: causes bradycardia and may predispose to heart block when used concomitantly with other drugs
KETAMINE: causes nodal rhythms and tachycardia, along with dysrhythmias associated with SNS activation
Describe potential rhythm disturbances with commonly used local anesthetics.
LA block calcium channels which can cause a wide QRS and QT prolongation.
What is the WHO definition of anemia of men and women?
Men: hgb 13-14.2 g/dl
Women: hgb 11.6-12.3 g/dl
Describe the “10/30” rule.
if hgb 10 or less —> transfuse
if hct 30 or less —> transfuse
Define restrictive and liberal transfusion therapies.
- Restrictive transfusion strategy recommends transfusion of allogeneic RBC one the hemoglobin concentration falls below 7 g/dl, and maintaining the hemoglobin concentration at 7-9 g/dl
- Liberal transfusion strategy recommends transfusion of enough allogeneic RBC to maintain the hemoglobin concentration at 10-12 g/dl
What is the definition for transfusion trigger?
- A specific critical hemoglobin concentration that does not allow for adequate oxygen transport has not been established in humans, and therefore, a widely accepted “transfusion trigger” does not exist.
- Authors define a transfusion trigger as, “A critical hemoglobin concentration, or the point at which compensatory mechanisms for anemia have been maximized and further reduction in hemoglobin concentration would result in compromised cellular metabolism”
Hemoglobin concentrations > 16 g/dl can cause(name 3 things)?
- high blood viscosity
- increased thrombus formation
- RBC aggregation
- platelet activation, adhesion and aggregation
Which clotting pathway does Hemophilia A affect? Hemophilia B?
Hemophilia A—>intrinsic
Hemophilia B—>intrinsic
Other names for Hemophilia A and B are?
Hemophilia A—>Factor VII deficiency
Hemophilia B—>Christmas Disease(deficiency of factor IX)
Which proteins are malformed in patients with Sickle Cell Disease?
-BETA-Globin protein
Congenital presence of abnormal Hgb S, allows RBCs to undergo sickle transformation, occlude the vasculature of lyse
Mutation on the 11th chromosome that causes a valine molecule to be substituted for glutamic acid in the BETA-GLOBIN protein.
Methods to reduce complications of sickle cell include(name 4):
- adequate oxygenation
- prevention of vascular stasis
- normothermia
- adequate hydration
- prevention of increased oxygen consumption
How much does 1 unit of platelets increase the platelet count?
Each unit of platelets can be expected to increase the count by 5000-10,000(unless aphorisms then 30-60K)
Who is at risk for developing HIT?
Any patient treated with heparin is at risk for developing HIT(inpatient/outpatient therapy)
Which coagulation factors are present in FFP?
ALL coagulation factors are present in FFP
THE REVERSAL DOSE OF FFP FOR COUMADIN THERAPY IS 5-8 ML/KG
Can cryoprecipitate cause non hemolytic blood reactions?
Yes, it contains anti-A and anti-B antibodies so MUST BE TYPED
What is the most commonly used replacement fluid?
Lactated Ringers
Due to the high sodium and chloride content, normal saline can cause ___ ___ ___.
dilutional hypercholemic acidosis
Name 2 colloids:
- Albumin
- Hespan
The storage of blood is associated with a ___ in ATP and 2.3 DPG, causing a ___ shift in the oxyhemoglobin curve.
- decrease
- leftward
Which coagulation test measures heparinization?
ACT
Which coagulation test measures the extrinsic pathway?
INR
Which coagulation test measures the intrinsic pathway?
PTT
What drug rapidly neutralizes heparin?
protamine sulfate
Giving Hespan in the same line as blood my result in ___.
anaphylaxis