EMT230 Flashcards
A medic notes deep and symmetrically inverted T waves—what does this indicate?
Cardiac ischemia
10 leads—4 on the limbs and 6 on the chest—is called what?
12-lead
50 year-old patient who has diabetes, is overweight, and smokes—asks you about his risk of cardiovascular disease. What do you tell him?
He can modify his risk for cardiovascular disease by losing weight and not smoking.
Pt has regular bradycardia rhythm with a rate of 40, no P waves, and a QRS greater than 0.12. Medic should diagnose what rhythm?
Ventricular escape rhythm
Pt with SVT begins to develop chest pain, and bp drops to 100/60. What treatment is next?
Synchronous cardioversion
Right axis shift of the ECG is noted when the QRS deflection has what characteristic?
Negative in lead I, negative or positive in lead II, and positive in lead III
After an initial defibrillation, what should the second and subsequent defibrillations for pediatric patients be set at?
4 j/kg
After medics administer nitro 0.4 mg SL to a pt with chest pain who has ST elevation in leads II, III and AVF, pt’s bp drops to 78/50. Where is the most likely location of cardiac muscle damage?
Inferior wall and right ventricle, which increases the dependence on preload
ECG strip shows a regular rhythm with a QRS complex of .08, rate 145, PR interval of .12 and one upright P-wave before each QRS complex. What rhythm should the medic suspect?
Sinus tachycardia
ECG strip shows a rhythm with a rate of 45, QRS of .08, and P wave that appears after the QRS. What rhythm should the medic suspect?
Junctional
Inferior-wall MI is usually caused by occlusion of the ___ artery.
Right coronary
During assessment, medic discovers a carotid bruit. What underlying condition should the medic suspect?
Atherosclerosis
Each small square of graph paper represents ___ mV.
0.1 mV
Each square on ECG paper is __ mm in height and width.
1
ECG analysis reveals that each P wave has different shape. Heart rate is 80 bpm. What rhythm should the medic suspect?
Wandering pacemaker
How can you help reduce impedance of the electrical current?
Ensure that excessive chest hair is shaven before patch placement
How is an aortic dissection usually described?
Ripping or tearing sensation
How does ACh affect the heart?
Decreases heart rate
How does atropine affect the ventricular rate of 3rd degree heart block?
Has no effect on the rate
How is preload defined?
Ventricular end-diastolic volume
How should a second degree type II heart block be considered?
Serious arrhythmia regardless of s&s
How will parasympathetic stimulation affect the heart?
A decreased rate
If a pt is in cardiogenic shock, when should signs of cardiogenic shock develop?
After hypovolemia and dysrhythmias have been corrected
If a pt with cardiac tamponade becomes hypotensive in the field, what should we do?
Administer a fluid bolus
If a-fib has been present for 48 hours+, conversion of the rhythm may lead to what?
Release of emboli
If a ventricle loses 25% of its muscle mass because of MI, what effect will it have?
The heart can still pump effectively
In a 12-lead ECG, what cardiac position are the leads V1 and V2?
Septal
In lead II placement, where is the positive lead located?
Left leg
In order to determine ST segment elevation, what is the amount that the ST segment must be elevated?
My more than 0.1 mV in at least 2 leads (more than 1 small box)
In the event of a coronary artery blockage, how could the muscle of the heart still receive blood?
Anastomoses
In what pt position should jugular vein distension in cardiac pt’s be evaluated?
With head elevated 45 degrees
Lead I looks at the heart from what view?
Lateral
Of what branch is the circumflex artery?
Left coronary artery
On an ECG, how will pulseless electrical activity present?
Any electrical activity other than the ventricular fibrillation or ventricular tachycardia
Pacemakers are usually set to a rate of ___ bpm beginning with ___ milliamps?
70-80 bpm, 50 mA
Medics are evaluating a 40 y/o woman in an airport who began to experience pain in her left lower leg after a 12 hour flight. Leg is warm, swollen, painful. What should you suspect?
Deep vein thrombosis
ECG tracing: wide QRS complexes that were produced with supraventricular activity. On MCL1 you see a QS pattern, what should you suspect?
Left bundle branch block
Which lead is placed on the 4th intercostal space just to the right of the sternum?
V1
An ECG exam of a 65 year-old man: ventricular heart rate is 56, more P waves than QRS complexes. PR interval is constant when a QRS follows a P wave. QRS complexes are widened. What type of heart block should you suspect?
Second degree type II
Medics are evaluating a pt who is complaining that his heart is “skipping beats.” On ECG evaluation, paramedics see frequent PVCs that are occurring in groups. BP is 100 systolic. What should treatment include?
Withhold treatment until serious signs and symptoms develop
Medics are treating a pt who is in PEA following home dialysis. What drug might be indicated?
Sodium bicarb
Medics discover a pt in asystole. In regards to electrical therapy, how should the medic proceed?
Electrical therapy is not recommended
Medics have determined that a pt is in a-fib, unstable, and requires electrical therapy. They should perform ___ countershock with ___ joules.
synchronized
120-200
Patients with pulseless v-tach should be treated in the same way as what other dysrhythmia?
V-fib
Phase 1 of the action potential represents which period?
Early rapid repolarization
Second degree type II heart block occurs when the impulse is not conducted through what portion of the cardiac electrical system?
Bundle branches
How much time does each small block on the ECG represent?
0.04 second
Stroke volume depends on preload, afterload, and what other factor?
Myocardial contractility
The AV junction is formed by the AV node and what other part of the cardiovascular electrical system?
Bundle of His
The left circumflex mainly supplies blood to what part of the cardiac muscle?
Left atrium
The duration of the QRS complex should be ___ second.
0.08 - 0.10
The intrinsic rate for the ventricular pacemaker is ___ beats per minute.
20 to 40
The left anterior descending coronary artery mainly supplies blood to what part of the cardiac muscle?
Septum
The majority of acute myocardial infarctions involve what section of the heart?
Left ventricle
The patient’s ST segment elevation is seen in leads II, III, and aVF. What should the paramedic suspect?
Inferior-wall MI
The PR interval represents the time that it takes an electrical impulse to do which action?
Be conducted through the atria and the AV node
The resting membrane potential is determined primarily by the difference between the intracellular potassium and what ion level?
Extracellular potassium
The right atrium receives blood from the systemic circulation and the ___.
Coronary veins
The right coronary artery and the left anterior descending artery supply most of the blood to what part of the cardiac muscle?
Right atrium and ventricle
The ST segment is elevated because the damaged muscle is ___.
Constantly depolarized
The three characteristics of Wolff-Parkinson-White syndrome are a short PR interval, QRS widening, and a ___.
Delta wave
To increase cardiac output, which action must take place?
Increase both heart rate and stroke volume
Under normal conditions, what is the dominant pacemaker of the heart?
SA node
What are aneurysms most commonly the result of?
Atherosclerotic disease
What are most MI’s caused by?
Acute thrombotic occlusion
What can an ECG help determine?
Whether there is ischemic cardiac muscle
What does a depressed ST segment suggest?
Ischemia
What does an elevated ST segment suggest?
Injury
What does an increase in peripheral vascular resistance cause?
Decreased stroke volume
What does T wave inversion suggest?
Ischemia
What does the medication atropine inhibit?
Parasympathetic response
What does the ST segment reflect?
Early repolarization of the ventricles
What does the Starling law state?
Myocardial fibers contract more forcefully when they are stretched
What drug may improve the symptoms of cardiogenic shock patients in the field?
Dopamine
What is a blood pressure reading of 180/110 in an adult considered?
Stage 3 hypertension
What is a characteristic of a left bundle-branch block?
A Q wave is seen instead of an R wave in MCL1
What is a characteristic of chest pain associated with MI?
Is constant
What is a characteristic of ischemia caused by unstable angina?
Responds well to treatment with antiplatelet agents
What is a characteristic of junctional escape rhythm?
Occurs when the SA node fails to fire
What is a characteristic of normal sinus rhythm?
Electrical impulse originates from SA node
What is a characteristic of Prinzmetal angina?
Coronary arteries spasm
What is a characteristic of Wolff-Parkinson-White syndrome?
Preexcitation syndrome
What is a compensatory mechanism of the heart in the presence of chronic hypertension?
Enlarge the muscle mass of the heart
What is a hallmark trait of a-fib?
An irregularly irregular rhythm
What is a major effect of norepinephrine?
Vasoconstriction
What is a patient in left ventricular failure expected to have?
Activation of the renin-angiotensin-aldosterone system
What is a sign of a cardiac tamponade?
Muffled heart tones
What is a typical characteristic of third-degree heart block?
Regular but independent atrial and ventricular rhythms
What is an undesirable side effect of atropine?
Increased myocardial oxygen demand
What is characteristic of atherosclerosis?
Progressive narrowing of the lumen of medium and large arteries
What is emergency care for a bundle-branch block?
Aimed at the cause of the block if it is identifiable
What is parasympathetic control of the heart provided by?
Vagus nerve
What is right ventricular failure most often the result of?
Left ventricular failure
What is the activation of myocardial tissue more than one time by the same impulse called?
Reentry
What is the class I intervention for all symptomatic bradycardia?
There are no class I interventions
What is the definitive treatment for second degree type II?
Transvenous pacemaker insertion
What is the desired action of prehospital medications when treating a patient with left ventricular failure?
Reduce afterload
What is the first medication a paramedic should aminister to a patient with angina?
Oxygen
What is the first recommended treatment for SVT?
Valsalva maneuver
What is the first upward deflection on an ECG tracing?
P wave
What is the group of nerves that innervates the atria and ventricles known as?
Cardiac plexus
What is the initial pediatric defibrillation joule setting?
2 J/kg
What is the joule setting for the initial synchronous cardioversion of SVT?
100J
What is the major neurotransmitter for the parasympathetic system?
ACh
What is the meaning of sinus bradycardia?
The heart rate is less than 60 bpm
What is the most common arrhythmia in sudden cardiac arrest?
Ventricular fibrillation
What is the most common cause of death following MI?
Fatal dysrhythmia
What is the most important factor in determining stroke volume in a healthy heart?
Preload
What is the most likely cause of atrial flutter?
Rapid reentry
What is the most likely cause of second degree type II heart block?
Septal MI
What is the movement function of the sodium-potassium pump?
Potassium ions into the cell and sodium ions out of the cell
What is the position of comfort for a patient with left ventricular failure?
Sitting with legs dependent
What is the prehospital care for a patient in second degree type II heart block?
Transcutaneous pacing
What is the treatment of choice for a severe symptomatic ventricular escape rhythm?
Pacing
What is the valve between the right atrium and right ventricle?
Tricuspid valve
What is typically found on an ECG with a bundle-branch block?
A widened QRS complex
What kind of leads are II and III?
Inferior
What lead is routinely used for monitoring dysrhythmias?
Lead II
What may be a lethal treatment for a patient with a ventricular escape rhythm?
Lidocaine
What medical device should the paramedic suspect if an outline of a small box implanted under the skin in the left upper chest is observed?
Implantable cardioverter-defibrillator
What occurs during the period between action potentials?
There is excessive sodium in the cell
What organ(s) are at most risk in a hypertensive crisis?
Kidneys
What part of the ECG tracing is most important for detecting life-threatening arrhythmias?
QRS complex
What property of dopamine causes an increased heart rate?
Beta agonist
What sign is most indicative of a right ventricular infarct?
Peripheral edema
What sound is heard when the AV valves close during ventricular systole?
S1
What statement best describes the triplicate method of determining heart rate?
Accurate when the heart rhythm is regular and greater than 50 beats per minute
What statement is true about most new AEDs?
Use waveforms that are more effective at lower energy settings
What term describes relaxation of the heart?
Diastole
What will occur after an implantable cardioverter-defibrillator has delivered five shocks?
Not deliver more shocks until a slower rate is restored for 30 seconds
What will occur if the paddle positions are switched during defibrillation?
Defibrillation will occur as usual
When analyzing an ECG tracing, you notice that the rhythm is highly irregular. What is the best method to calculate the rate?
Six-second count method
When attempting to perform a vagal maneuver, what action is most appropriate?
Placing ice packs to the neck
When contacting medical control to terminate resuscitation efforts, what information is most important for the medic to relay?
Any treatment provided
When depolarization takes place, what action occurs?
Sodium ions rush into the cell
When does synchronous cardioversion deliver the energy?
10 ms after the peak of the R wave
When is fibrinolytic therapy contraindicated?
If patient has had recent laser eye surgery of less than 3 weeks
When is fibrinolytic therapy for an MI patient most effective?
When administered within 12 hours after the onset of symptoms
When is synchronized cardioversion most acceptable for patients with ventricular tacycardia?
If they have decreased cardiovascular function
When performing CPR on an adult, how many inches should the medic compress the chest?
At least 2
Where are dissections of the aorta typically found?
On the ascending aorta
Which cardiac pacemaker has an intrinsic rate of 40-60 beats per minute?
AV junction
Which class I (recommended) drug is used for the treatment of SVT?
Adenosine
Which home medications would indicate that your patient has a strong risk factor for heart disease?
Metformin
Which illness/complication may cause sinus bradycardia?
Intrinsic sinus node disease
Which is a bipolar lead?
Lead II
Which is a cause of PEA correctable in the field?
Tension pneumo
Which is true of abdominal aortic aneurysm (AAA)?
AAA may be asymptomatic as long as it is stable
Which of these nerve fibers mainly innervate the ventricles of the heart?
Sympathetic nerve fibers
Which rhythm is an absolute indication for unsynchronized cardioversion?
Ventricular fibrillation
Which statement best describes the firing characteristics of demand pacemakers?
When the patient’s rate drops below a preset number
Which statement is true in regards to the identification of bundle-branch blocks?
Can only be determined with a 12-lead ECG
Which statement is true of the coronary arteries?
The coronary arteries begin just above the aortic valve
Which statement is true regarding v-tach?
It may be triggered by a PVC
While analyzing an ECG, you cannot identify a Q wave. What does this most likely indicate?
The Q wave may not be visible in the lead you are viewing
While assessing a pt, medics note a pulatile mass in the abdomen. Suddenly this mass is no longer palpable and the patient’s blood pressure begins to drop. What is the most likely cause?
Patient’s aneurysm has ruptured
Wolff-Parkinson-White syndrome is of little clinical importance unless the patient is experiencing what condition?
Tachycardia
You are called to evaluate a 64 year-old woman who complains of palpitations, weakness and dizziness. HEr heart rate is 160 bpm, bp 118/80, resp rate is 28. The ECG tracing shows narrow QRS complexes and no identifiable P waves. Which rhythm should you suspect?
SVT
You are treating a 75 year-old woman who has a history of diabetes and atherosclerosis. Her chief complaint is persistent heartburn. What should the medic suspect?
This may be a cardiovascular problem
You are treating a pt who has a damaged SA node that is no longer pacing the heart. What cardiac finding should you expect to find?
Bradycardia
You see an irregular rhythm on the monitor with a rate of 66-80, a normal PR interval, and a P wave for every QRS. The rate speeds up and slows down with the patient’s respiratory rate. What rhythm should you suspect?
Sinus dysrhythmia
___ second is measured in each large box on ECG graph paper.
0.20 second
The circumflex branch of the left coronary artery mainly supplies blood to what part of the cardiac muscle?
Left atrium
Would a pt with acute CHF with pulmonary edema have stridor lung sounds?
No
What could different blood pressures per arm indicate?
AAA
Heart rate of 30, normal P wave, QRS less than 0.12—what rhythm?
Sinus bradycardia
What would a pacer spike not followed by a QRS wave indicate?
Pacemaker failure
Lasix is what type of drug?
Diuretic
What is not part of the autonomic nervous system?
Spinal cord
Inotrope definition?
Force of cardiac contraction
Analysis of ST segment is not part of what?
Initial ECG
ECG cannot read what?
CO
Second degree type II is from what area?
Septal MI
The circumflex is part of what coronary artery?
Left coronary artery
What drug helps hypertension but has no effect on the heart?
ACE inhibitor
What is one characteristic of an idioventricular rhythm?
QRS greater than 0.12
A second degree type II block occurs when what happens?
Electrical impulse is not conducted through the bundle branches
What lung sounds would you expect to hear in a pt with pulmonary edema?
Rales
Rhonchi
Wheezing
A-fib responds well to what type of drug?
Calcium channel blocker
Peaked T waves could indicate what condition?
Hyperkalemia
Why do we push so hard and fast during CPR?
To maintain a good bp
The apex of the heart is located where?
On the bottom (diaphragm) side of the heart
Torsades de pointes is what kind of rhythm?
Polymorphic ventricular tachycardia
Polymorphic ventricular tachycardia can degenerate into what rhythm?
Ventricular fibrillation
Medication that may help with torsades de pointes?
Mag sulfate
How do beta blockers work?
They work by decreasing cardiac output and inhibiting renin secretion from the kidneys, which results in lower bp
How do ACE inhibitors work?
Inhibits the conversion of the precursor angiotensin I to angiotensin II, the renin-angiotensin-aldosterone system is suppressed and blood pressure is lowered
What is a U wave?
Only sometimes visible
Thought to represent repolarization of the Purkinje fibers
When using the R-R method, how do you calculate heart rate using the distance in seconds?
Measure the distance in seconds between two R waves
Divide this number into 60
When using the R-R method, how do you calculate heart rate using large squares?
Count the large squares between the R waves
Divide this number into 300
When using the R-R method, how do you calculate heart rate using small boxes?
Count the small boxes between R waves
Divide this number into 1500
Name one characteristic of an idioventricular rhythm
Wide (>0.12) QRS complex
What will you see on an ECG to indicate potential ischemia?
ST depression
Name some causes of pulseless electrical activity (PEA)
Tamponade, cardiac Tension pneumothorax Pulmonary embolism MI Hypoxia Hypo-/hyperkalemia Overdoses Hypovolemia
What is one critical element of resuscitation in cardiac arrest situation with v-tach?
Defibrillation
What is a second degree type II av block? When does it occur? How will you recognize it?
Occurs when impulses are not conducted from atria to ventricles
Distinct ECG pattern: consecutive P-waves with a constant PR interval with intermittent dropped QRS complex
The right atrium receives blood from the systemic circulation and ___?
Coronary veins
What does it mean when the monitor will not pace?
You don’t have capture
What is the PR interval?
Indicates the time required for an electrical impulse to be conducted through the atria and AV node
What occurs after the action potential peaks?
Repolarization
How will hyperkalemia show on an ECG?
Peaked T waves
What lung sounds will you hear with CHF?
Crackles
Rhonchi
Rales
Wet lung sounds
What lab work will the hospital do to detect an MI?
Troponins
CK
CK-MB
Symptomatic bradycardia - most important intervention?
Transcutaneous pacing
Amiodarone doses for cardiac arrest? First/second?
First bolus = 300 mg
Second bolus = 150 mg
IV/IO
Arteriosclerosis vs atherosclerosis
Arteriosclerosis = thickening and hardening of the walls of the arteries Atherosclerosis = lipid/cholesterol buildup in the inner walls of the arteries, causing narrowing
What is Wolff-Parkinson-White syndrome?
What is a critical condition in it?
WPW is a genetic heart abnormality associated with early activation of the ventricles
In tachycardia, this preexcitation syndrome can be life-threatening
Dopamine - when used? (2) What dosage?
When: second-line drug for symptomatic brady (after atropine), also for hypotension (
How do we determine STEMI in 12-lead?
ST elev of 1mm+ in 2 contiguous leads
CPAP is indicated for what patients?
Used for pts with: Acute respiratory distress syndrome (ARDS) Asthma COPD CHF Pneumonia Pulmonary edema
DO NOT use for unconscious pts, under 14 y/o, hypotension/shock, chest trauma, pneumo, GI bleeding
Atropine given too slowly can do what?
Can cause a rebound bradycardia
What is the mechanism of action of dopamine?
Stimulation of beta 1 receptors is primary effect, which increases cardiac output and only has a modest increase in systemic vascular resistance
What kind of rhythm is a-fib?
Irregularly irregular
What is an indication of a paced rhythm?
Presence of pacer spikes
How do we listen for basic heart sounds S1 and S2?
S1 = ask pt to breathe normally and hold the breath in expiration S2 = ask pt to breathe normally and hold the breath in inspiration
Which valve is located between the right atrium and right ventricle?
Tricuspid
Which routes can atropine be administered?
IV, IO, ET tube
Define preload
End-diastolic volume in the ventricles
Define afterload
Pressure in the aorta before ventricular contraction; the total resistance against which blood must be pumped
What nerves innervate the atria and ventricles?
Cardiac plexus
What is the dosage for lidocaine in cardiac arrest from VF/VT? Initial and refractory dose?
Initial = 1 to 1.5 mg/kg IV/IO
Refractory = 0.5 to 0.75 mg/kg IV push
Repeat in 5-10 min, max 3 doses or 3 mg/kg
