Chapter 16-Cardiovascular Emergencies Flashcards
How does the heart control heart rate?
It has control over its own electrical impulses which allow the atria and ventricles to work together
Where do the electrical impulses of the heart start?
Sinoatrial (SA) node
After an electrical impulse starts at the SA node, where does it go?
Across the atria, causing them to contract
Where does the electrical impulse of the heart go after causing the atria to contract?
The atrioventricular (AV) node
What happens to the impulse at the AV node?
It gets slowed for 0.1-0.2 seconds to allow blood to pass from the atria to the ventricles
After passing through the AV node, where does the heart’s electrical impulse go?
It spreads across the ventricles via the bundle of His, the right and left bundle branches, and the purkinje fibers
How is the initial electrical impulse at the SA regulated?
By the brain via the autonomic nervous system
What is blood made up of?
Red blood cells (move oxygen), white blood cells (fight infection), platelets (help with clotting), and plasma (fluid)
What’s happening during diastole?
The aortic valve closes and blood flow between the left ventricle and aorta stops while the left ventricle refills with blood
Where can peripheral pulses be felt?
Brachial, radial, posterior tibialis, and dorsis pedis arteries
Where can central pulses be felt?
Carotid and femoral arteries
What are the three components require for good perfusion?
Well-functioning heart
Adequate volume of blood
Appropriately-sized vessels
What is atherosclerosis?
A condition in which calcium and cholesterol build up and form plaque inside a vessel
When plaque build up, what part of the vessel decreases in size?
The lumen, or diameter
What happens when an atherosclerotic plaque cracks?
It triggers a blood clotting response that can obstruct the vessel or cause the plaque to get dislodged and flow through the vessel
What is it called when an atherosclerotic clot gets dislodged and starts flowing through a vessel?
Thromboembolism
What is it called when a thromboembolism gets stuck in a coronary artery?
Acute myocardial infarction (AMI)
What does infarction mean?
Tissue death
What are controllable risk factors for AMI?
Cigarette smoking, high cholesterol, high blood pressure, high blood glucose, lack of exercise, obesity
What are uncontrollable risk factors for AMI?
Old age, family history, race, ethnicity, sex (male)
What is acute coronary syndrome?
a group of symptoms that are caused by myocardial ischemia?
What is myocardial ischemia?
reduced blood flow to the heart
What are the terms for the two types of myocardial ischemia?
Angina pectoris and acute myocardial infarction
What are two causes for angina pectoris?
spasm of an artery or atherosclerotic coronary artery disease
How is angina pectoris pain described?
A crushing/squeezing pain in chest that can radiate to jaw, left arm, center of back, or upper middle abdomen
How long does angina pain usually last?
3-8 minutes
What are two subcategories of angina
Unstable, occurs in absence of triggers and leads to AMI, and stable, occurs only in the presence of triggers and goes away when triggers are removed or nitroglycerin is administered
What are triggers for angina?
exertion (physical or emotional), large meal, sudden fear
What are three ways in which AMI pain differs from angina pain?
Lasts longer (30 min to several hours), Can’t always be relieved by nitroglycerin, and can occur in absence of trigger
What is the first thing you do for someone with chest pain?
Position: supine or Fowler’s (remove or loosen tight clothing)
After you have positioned a patient with chest pain, what other things do you have to do?
Administer oxygen and constantly reassess patient’s oxygen saturation and breathing and administer low dose aspirin or nitroglycerin
What does aspirin do for a patient with chest pain?
Reduces blood clots to prevent clots from getting bigger
What is the recommended dose of aspirin?
2-4 81 mg tablets
What do you have to make sure of before administering aspirin?
(1) patient isn’t allergic (2) no history of internal bleeding
What does nitroglycerin do for a patient with chest pain?
relaxes the muscles of vessel walls, dilates coronary arteries, increases blood flow and reduces the workload placed on the heart
In what forms does nitroglycerin come?
Pill, sublingual spray, patch
What are the side effects of nitroglycerin?
headache, low bp, changes in hr
What do you do between doses of nitroglycerin?
Check bp 5 minutes after administering each dose and if systolic is under 100, do not continue administering
What are some reasons to not give a patient nitroglycerin?
Head injury, they used erectile dysfunction drugs in the past 24 hours, or if you’ve already administered the maximum three doses
Step 1 of administering nitroglycerin:
Obtain permission from medical control
Step 2 of administering nitroglycerin:
Check bp to make sure it’s under 100
Step 3 of administering nitroglycerin:
Check expiration date, contamination, and prescription
Step 4 of administering nitroglycerin:
Ask patient how many doses they’ve already taken
Step 5 of administering nitroglycerin:
administer or help patient administer medicine, and warn them not to chew tablet
What should you be doing throughout the entire time you’re administering nitroglycerin?
Recording times of administration and checking bp 5 minutes after each dose
Most AEDs regulate the _____ based on the _____
voltage, impedance
What are shockable rhythms?
Ventricular fibrillation and ventricular tachycardia
What are not shockable rhythms?
asystole, pulseless electrical activity
What is the chain of survival for cardiac arrest?
Activation of EMS CPR AED Basic and Advanced EMS ALS and post arrest care
What are 6 common mistakes/challenges associated with using a defibrillator?
- Failure of machine to detect shockable rhythm
- Applying pads to a moving patient
- Turning off AED before shock/analysis is complete
- Not pushing the shock/analyze button when needed
- Failing to keep battery charged
- Using on a responsive patient with a pulse but whose hr is high enough to confuse the AED into thinking they’re in V-tach
What usually causes cardiac arrest in children?
respiratory failure
How should you modify defibrillation of children if possible?
Use pediatric pads
How should you modify defibrillation of infants if possible?
Use manual defibrillator if available, if not use AED with pediatric dose attenuator, if not use adult pads
