Cardiac emergencies

Question 1

What is the primary function of the cardiac conduction system?

Answer 1

To generate electrical impulses that conduct rapidly to other cells of the heart (Known as conductivity)

This property is known as conductivity.

Question 2

What are the 3 groups of conductive cells?

Answer 2

in pacemaker sites with automaticity (the ability to conduct impulses automatically). the locations are as follows: SA node, AV node, and purkinje fibers.

The SA node is known as the primary pacemaker of the heart.

Question 3

What happens if the sinoatrial node fails?

Answer 3

The atrioventricular (AV) node generates an impulse and if this fails, the purkinje fibers generate an impulse but it will not maintain ventricular contraction as effectively.

The AV node is a secondary pacemaker site.

Question 4

What are Purkinje fibers responsible for?

Answer 4

Delivering the impulse to the working cells of the heart

They can initiate an impulse if both higher pacemaker sites fail.

Question 5

What are working cells?

Answer 5

also called contractile cells. Their
primary purpose is to contract in response to the electrical impulses provided by the conduction system.

Conductive cells generate impulses, while contractile cells respond to them.

Question 6

what is depolarization and repolarization?

Answer 6

Each heartbeat, or mechanical contraction of the
heart, has two distinct components of electrical activity: depolarization and repolarization. Depolarization is
the first, in which electrical charges of the heart muscle
change from negative to positive and cause heart muscle
contraction. Repolarization is the second component,
in which the electrical charges of the heart muscle return
to a resting negative charge and cause relaxation of the
heart muscle.

It can occur due to increased pressure in the pulmonary vessels.

Question 7

Describe the P wave

Answer 7

This is the first waveform of the ECG and
represents the depolarization (contraction) of the atria.

From there, it is pumped into the left ventricle.

Question 8

Describe the QRS complex

Answer 8

This is the second waveform and represents the depolarization (contraction) of the ventricles and the main contraction of the heart.

This is necessary due to the high pressure in the aorta.

Question 9

Describe the T wave

Answer 9

This is the third waveform and represents
the repolarization (relaxation) of the ventricles.

This is caused by pressure buildup in the left atrium and pulmonary veins.

Question 10

What is the PR interval?

Answer 10

It represents the time it takes the heart’s electrical impulse to travel from the atria to the ventricles.

It provides a graphic representation of depolarization and repolarization.

Question 11

The degeneration of the electrical conduction system.

Answer 11

the electrical conduction system
can be damaged or disturbed and cause the improper
functioning of the heart. Sometimes, these conditions produce an irritability of the heart that causes the
uncoordinated firing of electrical ventricular impulses
called premature ventricular complexes (PVC). When
PVCs occur in succession, they can produce ventricular tachycardia (V-Tach), which displays on an ECG as
steep peaks and valleys that are close together. If left
untreated, ventricular tachycardia can degenerate into
ventricular fibrillation (VF or V-Fib), which shows up as
smaller, uneven, disorganized peaks and valleys.

Each component represents different phases of electrical activity in the heart.

Question 12

Blood flow of the heart

Answer 12

1. inferior and superior vena cava
2. right atrium
3. tricuspid valve
4. right ventricle
5. pulmonary valve
6. pulmonary arteries
7. lungs dispose of CO2 & pick up O2
8. pulmonary veins
9. left atrium
10. mitral valve
11. Left ventricle
12. aortic valve
13. Aorta
14. Blood goes to the rest of the body

It is measured from the beginning of the P wave to the beginning of the QRS complex.

Question 13

Why does classic agina occur?

Answer 13

typically occurs upon an
increased workload placed on the heart. This can be
from an increase in the heart rate or contractile function.

Question 14

What does unstable agina usually indicate

Answer 14

angina discomfort that is prolonged and
worsening or that occurs without exertion and when the
patient is at rest.

Question 15

Patho of Agina Pectoris

Answer 15

Angina pectoris is a symptom
of inadequate oxygen supply to the heart muscle, or
myocardium. As noted earlier, it typically results from a decrease in oxygen delivered to the myo-
cardium, which is often caused by partial blockage of the
coronary arteries, which causes ischemia (reduced deliv-
ery of oxygenated blood) that results in tissue hypoxia
(oxygen deficiency in the tissues). Angina can also occur
from a dramatic increase in demand on the heart such as
from a cocaine-induced myocardial infarction. The lack
of oxygen causes the discomfort, sometimes described as “crushing,” or “squeezing,” or as a “tightness” by the
patient

Question 16

Where is the pain of Agina usually felt?

Answer 16

The pain is usually felt under the sternum and can radiate to the jaw, down either arm, to the
back, or to the epigastrium (upper-center region of the
abdomen). The pain usually lasts for approximately 2–15
minutes. Many patients can tell you that they have had
angina as part of their past medical history and have
nitroglycerin prescribed for this condition. Prompt relief
of the symptoms after rest and administered nitroglycerin
is typical of angina.

Question 17

What are common symptoms of angina pectoris?

Answer 17

• Steady discomfort, usually located in the center of the
chest but can be more diffuse throughout the front of
the chest
• Discomfort that is usually described as pressure, tight-
ness, aching, crushing, or heavy
• Discomfort that might radiate to the shoulders, arms,
neck, jaw, back, or epigastric region (upper center
abdomen)
• Cool, clammy skin
• Anxiety
• Dyspnea (shortness of breath)
• Diaphoresis (excessive sweating)
• Nausea and vomiting
• Complaint of indigestion pain

Symptoms can vary, especially in women, diabetics, and the elderly.

Question 18

What should be done if classic angina is not relieved after three nitroglycerin tablets and rest?

Answer 18

Recognize it as an acute coronary syndrome emergency and provide prompt treatment

This indicates a potentially serious condition.

Question 19

Characteristics of unstable angina

Answer 19

pain
or discomfort that occurs at rest, continues without relief,
or is prolonged. If the patient experiences angina that
occurs at rest and lasts for more than 20 minutes, angina
with a recent onset that progressively worsens, or angina
that wakes the patient at night (nocturnal angina), you
should view it as an acute coronary syndrome emer-
gency and provide prompt treatment and transport.

Question 20

Emergency medical care angina pectoris

Answer 20

You should establish an
open airway. If the patient’s respirations become inad-
equate, begin positive pressure ventilation. Apply the
pulse oximeter, if available, to monitor the oxygen level.
Administer supplemental oxygen if the patient is dys-
pneic, hypoxemic, has obvious signs of heart failure, has
an SpO2 of 694%, or the SpO2 is unknown. Initiate oxy-
gen therapy via a nasal cannula at 2 lpm and titrate the
concentration and liter flow to achieve and maintain an
SpO2 of 94% or greater.

Question 21

What should you do if a patient has prescribed nitroglycerin and a systolic blood pressure greater than 90 mmHg?

Answer 21

Place him in a sitting or lying position and administer nitroglycerin tablets or spray

Question 22

What is the recommended aspirin dosage for suspected coronary artery occlusion?

Answer 22

160–325 mg

Question 23

What is an acute myocardial infarction (AMI)?

Answer 23

When a portion of the heart muscle dies due to lack of oxygenated blood

Question 24

Patho of AMI

Answer 24

An acute myocardial infarction
typically is the result of coronary artery disease that
causes severe narrowing or complete blockage of the
coronary arteries. A plaque erosion or rupture within
the coronary artery can cause the narrowing and block-
age to occur. The result is a portion of heart muscle
that does not receive an adequate supply of oxygenated
blood. After approximately 20–30 minutes without ade-
quate perfusion, the heart muscle begins to die. When the blood flow is blocked, the heart muscle
becomes ischemic (hypoxic from inadequate oxygen-
ation). If the blood flow is not restored to that portion of
heart muscle, the cells begin to die.

Question 25

What are common dysrhythmias that can occur during a heart attack?

Answer 25

Ventricular fibrillation and ventricular tachycardia

Question 26

How can you re-establish blood flow in the coronary artery?

Answer 26

fibrinolytic agents, commonly referred to as “clot busters,” it might be possible to dissolve the clot, reopen the coro- nary artery, and restore perfusion to the ischemic heart muscle.

Question 27

How does chest discomfort from an AMI differ from angina?

Answer 27

AMI discomfort lasts longer and is usually not relieved by nitroglycerin

Question 28

List some signs and symptoms of an acute myocardial infarction.

Answer 28

• Chest discomfort radiating to jaw, arms, shoulders, or back • Anxiety • Dyspnea • Sense of impending doom • Diaphoresis • Nausea and vomiting • Light-headedness or dizziness • Weakness

Question 29

Which populations are more prone to atypical presentations of heart attack symptoms?

Answer 29

Diabetics, the elderly, and women

Question 30

What is an silent MI

Answer 30

no chest discomfort is experienced. They might complain only of shortness of breath, nausea, light-headedness, or weakness.

Question 31

Emergency medical care for a suspected AMI?

Answer 31

Ensure a patent airway and provide positive pres- sure ventilation with oxygen connected to the device if the breathing is inadequate. If the respiratory rate and tidal volume are both adequate, consider supplemental oxygen. Administer supplemental oxygen if the patient is dyspneic, is hypoxemic, has obvious signs of heart failure, has an SpO2 of 694%, or the SpO2 is unknown. Initiate oxygen therapy via nasal cannula and titrate the concentration and liter flow to achieve and maintain an SpO2 of 94% or greater. Place the patient in a position of comfort. If the patient has a prescription for nitroglycerin, adminis- ter one tablet every 3–5 minutes up to a total of three tablets. Follow your local protocol. Be sure the systolic blood pressure is above 90 mmHg and remains above 90 mmHg following each nitroglycerin administration. If local protocol allows, administer 160–325 mg of aspirin.

Question 32

Patho of Aortic Aneurysm

Answer 32

when a weakened section of the aortic wall, usually resulting from atherosclero- sis, begins to dilate or balloon outward from the pres- sure exerted by the blood flowing through the vessel. An aneurysm can exist for a long time with no symp- toms or signs that the patient is aware of and then sud- denly rupture, causing rapid and fatal internal bleeding (Figure 17-10 ■). Aortic aneurysms occur most often in the abdominal region. Pain can be felt, especially in the back, when the aneurysm gets large enough, perhaps shortly before rupture occurs. Usually, the aorta can- not be felt with a physical examination, but at this final stage it can be felt as a pulsating mass in the abdomen, although this can be difficult or impossible to detect in a heavy-set patient.

Question 33

Patho of aortic dissection

Answer 33

there is a tear in the inner lining of the aorta and blood enters the opening and causes separation of the layers of the aortic wall. Aortic dissections occur most often in the thorax. The pain is classically most severe when the dissection first occurs and is most often described as a “sharp” pain, or sometimes as a “tearing” or “ripping” pain, often felt in the back, flank, or arm. Syncope might be the only sign in some patients. Depending on the location of the dissection along the aorta, it can cause symptoms similar to a stroke or to a myocardial infarction and can lead to a myocardial infarction or other damage to the heart. A difference of 20 mmHg or greater in the systolic blood pressure reading between the upper arms or a severe decrease or difference in the upper and lower extremity pulse amplitude as compared to central pulses in a patient complaining of back or sharp chest pain should cause you to suspect a possible aortic dissection.

Question 34

What should be done if aortic aneurysm is suspected?

Answer 34

Administer oxygen and transport the patient immediately

Question 35

What is an aortic aneurysm?

Answer 35

A weakened section of the aortic wall that dilates or balloons outward

Question 36

What characterizes aortic dissection?

Answer 36

A tear in the inner lining of the aorta causing separation of the layers

Question 37

What type of pain is typically associated with aortic dissection?

Answer 37

Sharp, tearing, or ripping pain

Question 38

How to treat AA?

Answer 38

If a pulsating mass is felt and aortic aneurysm is suspected, administer oxygen and transport the patient immediately because only surgery can prevent or repair a rupture of the aneurysm. For a chest or back pain that can result from an aortic dissection or that can be a symptom of myocardial infarction, administer oxygen and assist the patient with prescribed nitroglycerin if the blood pressure is more than 90 mmHg and no signs of hypovolemia are present. If aortic dissection is sus- pected, do not administer aspirin.

Question 39

What causes heart failure?

Answer 39

Inadequate ejection of blood from the ventricle

Question 40

Patho of left heart failure

Answer 40

Left ventricular failure occurs when the left ventricle cannot pump blood out of the left ventricle effectively (Figure 17-12 ■). This reduces blood flow to the arteries and the perfusion of blood to the cells throughout the body. Furthermore, blood waiting to enter the left ventri- cle from the left atrium and blood waiting to enter the left atrium from the lungs backs up in a sort of “traffic jam.” When the left ventricle fails to eject the normal amount of blood with each contraction, the blood pressure begins to build up in the left atrium. The increase in pressure in the left atrium causes an increase in pressure in the pul- monary veins, which are responsible for delivering blood from the lungs to the heart. The increase in pressure in the pulmonary veins creates a higher pressure in the cap- illaries in the lungs. Remember that the capillaries in the lungs are the sites of gas exchange with the alveoli. When the pressure in the capillaries increases, fluid begins to leak out between the capillary and the alveoli. The fluid collects between the capillary and around the alveoli and distal bronchioles. This causes the space between the capillary and the alveoli to widen, making gas exchange more difficult. The poor gas exchange leads to hypoxia. This condition is referred to as pulmonary edema.

Question 41

Patho of right heart failure?

Answer 41

When the right side of the heart fails, the blood backs up into the venous system. The right side of the heart can fail due to failure of the left ventricle. It can also fail because of cardiac valve disease or an increase in pulmo- nary vessel pressure (pulmonary hypertension). Chronic obstructive pulmonary disease (COPD) can increase the pressure in the pulmonary vessels in the lungs and cause the right ventricle to work much harder. Over time, this can cause the right ventricle to fail. Signs include periph- eral edema, jugular vein distention, and liver enlargement.

Question 42

What are common findings in left ventricular failure?

Answer 42

When the left ventricle fails, the cardiac output drops and there is a diminishment in the perfusion pressure to the rest of the body’s organs. Common findings include a drop in systolic blood pressure (to include frank hypo- tension), diminished or absent peripheral pulse ampli- tude, altered mental status, changes in the heart rate, poor urinary output, respiratory distress, inspiratory rales, and possible pulmonary edema.

Question 43

Findings within right ventricular failure

Answer 43

Remember that the right ventricle pumps blood to the lungs for reoxygenation. If the right-sided cardiac output starts to drop, the lungs may be hypoperfused, which can lead to hypoxia and respiratory distress. Also, as the blood starts to accumulate in the ventricle from poor ejection, it eventually backs up into the atrium and subsequently into the vena cava. Findings of this can include jugular venous distension and peripheral edema. One other change in normal physiology is that if the right side is pumping inadequately, the left side of the heart receives an insuf- ficient amount of blood. Because the left ventricle can pump only as much blood as it receives, the patient might also display many of the previously mentioned findings of poor peripheral perfusion

Question 44

What is CHF? patho

Answer 44

refers to the condition in which there is a buildup of fluid (congestion) in the body resulting from the pump failure of the heart. It represents the condition in which the left, the right, or both ventricles are failing to meet the body’s needs. It may be a chronic condition that presents over a period, or it may be more acute,

Question 45

Treatment for heart failure

Answer 45

patent airway. Provide positive pressure ventilation with supplemental oxygen connected to the device if the breathing is inadequate.

Question 46

What is a common position heart failure patients assume to alleviate symptoms?

Answer 46

Upright position with legs, feet, arms, and hands dangling.

Question 47

What are some signs and symptoms of heart failure?

Answer 47

* Marked or severe dyspnea * Tachycardia * Orthopnea * Paroxysmal nocturnal dyspnea * Fatigue on exertion * Anxiety * Tachypnea * Diaphoresis * Cool, clammy, pale skin * Chest discomfort * Cyanosis * Agitation and restlessness * Edema * Crackles and wheezes * Decreased SpO2 reading * Blood pressure variations * Jugular venous distention * Distended abdomen

Question 48

What to do if a heart failure patient experiences chest discomfort

Answer 48

If the patient has a prescription for nitroglycerin, administer one tablet every 3–5 minutes to a total of three tablets. Follow your local protocol. Nitroglycerin can be beneficial to the patient by reducing the pressure in the arteries of the body, mak- ing it easier for the left ventricle to pump the blood out. Any venous dilation can cause less blood to return to the heart and reduce the workload of the ventricles. Ensure that the patient has a systolic blood pressure of greater than 90 mmHg prior to administration of nitroglycerin.

Question 49

What emergency care should be provided to a heart failure patient?

Answer 49

Ensure a patent airway and provide positive pressure ventilation with supplemental oxygen.

Question 50

What is the initial oxygen administration for a dyspneic heart failure patient?

Answer 50

Via a nasal cannula starting at 2 lpm, titrate to maintain SpO2 of 94% or greater.

Question 51

What is nitroglycerin used for in heart failure patients?

Answer 51

To reduce arterial pressure and decrease the workload on the heart.

Question 52

Indications you should use nitroglycerin

Answer 52

The patient exhibits signs and symptoms of chest pain or discomfort consistent with acute coronary syndrome. The patient has physician-prescribed nitroglycerin or it is carried on the EMS unit. The EMT has received approval from medical direc- tion, whether on-line or off-line, to administer the medication.

Question 53

What are contraindications for administering nitroglycerin?

Answer 53

The patient’s baseline systolic blood pressure is below 90 mmHg systolic or the systolic blood pressure has decreased greater than 30 mmHg from the baseline. The heart rate is less than 50 bpm or greater than 100 bpm. The patient has a suspected head injury. The patient is an infant or a child. Three doses have already been taken by the patient. The patient has taken tadalafil (Cialis) within the past 48 hours or vardenafil (Levitra) or sildenafil (Viagra) within the past 24 hours.

Question 54

What does nitroglycerin do?

Answer 54

Nitroglycerin dilates coronary arteries, peripheral arteries, and veins, causing an increase in coronary artery blood flow, a decrease in peripheral vascular resistance, and a decrease in the myocardial workload

Question 55

Side effects of nitroglycerin

Answer 55

The aim of administering nitroglycerin is to dilate blood vessels in the heart, but blood vessels in other parts of the body are dilated as well. This dilation can cause: Headache A drop in blood pressure Changes in pulse rate as the body compensates for the changes in blood vessel size

Question 56

What are the indications for administering aspirin?

Answer 56

Chest pain suggestive of acute coronary syndrome and approval from medical direction.

Question 57

Contraindications for aspirin?

Answer 57

Aspirin should not be given to a patient who is known to be allergic (hypersensitive) to the drug.

Question 58

Dosage of nitroglycerin?

Answer 58

The dosage of aspirin is 160–325 mg as soon as possible after the onset of the chest discomfort and symptoms of heart attack. It is recommended that 160–325 mg of a nonenteric aspirin be chewed and swallowed.

Question 59

Dosage of nitroglycerin

Answer 59

The dosage for EMT administration of nitroglycerin is either one tablet or one spray under the tongue. The most commonly prescribed dose is either 0.3 mg per tablet (or metered spray), or 0.4 mg per tablet (or metered spray). Regardless of the individual dose unit, the administered dose may be repeated in 3–5 minutes if (1) the patient experiences no relief; (2) the blood pressure remains greater than 90 mmHg systolic or does not fall more than 30 mmHg below the baseline systolic pressure; (3) the heart rate remains above 50 bpm and below 100 bpm; and (4) medical direction gives authorization. The total dose is three tablets or sprays, to include what the patient took prior to your arrival.

Question 60

What does Aspirin do?

Answer 60

Aspirin (acetylsalicylic acid [ASA]) is a medication that produces a rapid antiplatelet effect. This effect decreases the ability of platelets to clump together during the clot- ting cascade and reduces the formation of a clot in the coronary artery at the site of the blockage

Question 61

Side effects of aspirin

Answer 61

The patient may experience stomach irritation or heartburn, nausea, or vomiting