Chapter 17- Cardiovascular Emergencies Flashcards
How does oxygenated blood reach the heart?
Coronary arteries
Where is the point of maximal impulse located?
Left anterior chest, fifth intercostal space
What is the most inner layer of the heart?
Endocardium
What is the structure that protects the heart and provides lubrication for the heart between itself and surrounding structures?
Pericardium
What does the left main coronary artery subdivide into?
Left anterior descending artery and circumflex coronary artery
What valves make up the atrioventricular valves?
Tricuspid valve separates the right atrium from the right ventricle and the mitral valve separates the left atrium from the left ventricle. Both valves prevent backflow during ventricular contraction
What is the function of the chordae tendinae?
Prevent valve leaflets from inverting (prolapsing) during ventricular contraction
What valve prevents backflow from the artery into the right ventricle and separates the right ventricle from the pulmonary artery?
Pulmonic valve
What does the aortic semilunar valve do?
Prevents blood that has already entered the aorta from flowing back into the left ventricle
What is atrial kick?
The contribution to ventricular filling made by the contraction of the atrium
What is preload?
Initial stretching of the myocytes prior to the contraction of the left side of the heart
What is Afterload?
The pressure which the heart must pump against
What is systemic circulation?
All blood vessels between left ventricle and right atrium
What is pulmonary circulation?
Consists of all blood vessels between the right ventricle and left atrium
What is the exception to arteries?
The usually carry oxygenated blood but the pulmonary arteries are the exception. They carry oxygen depleted blood from the right ventricle to the lungs
What is the exception for veins?
Veins normally carry deoxygenated blood to the heart. The only exception are pulmonary veins, which carry oxygenated blood to the left side of the heart
What is cardiac output and what is normal for an adult?
The amount of blood pumped out by either ventricle, normal is 5-6 L/min
What is ejection fraction and what range is normal for adults?
The percentage of blood that leaves the heart each time it contracts. Left ventricular ejection fraction has a normal range of 55-70%
What kind of medication would have an effect on frank starling?
Inotropic
What is excitability?
Cardiac cells responding to an electrical impulse
What is conductivity?
Cardiac cells can pass an electrical impulse from one cell to another
What is automaticity?
Heart muscle can generate its own electrical impulses without stimulation from nerves
What causes a delta wave?
Bundle of Kent and bundle of his de polarizing at the same damn time
What is a key characteristic of an idioventricular rhythm?
20-40 bpm
What is a valsalva maneuver?
Pressure on the carotid sinus, straining against a closed glottis
What effect do beta-1 have on the heart?
Increases rate, force, and automaticity
What do andrenergic sympathetic nerves connect to?
Ventricles, vessels
What do cholinergic sympathetic nerves connect to?
Sweat glands, vessels
What do dopaminergic sympathetic nerves connect to?
Renal glands, vessels
What does atropine do?
Parasympathetic blocker, opposing the vagus nerve. Used to speed the heart when excessive vagal firing has caused bradycardia
What does norepinephrine (levophed) do?
Sympathetic agent causing vasoconstriction. Used to increase blood pressure when hypotension is caused by vasodilation such as in neurogenic shock. Almost pure alpha.
What would a Dopeamine dose of 1-2 mcg/kg/min be used for?
Increased renal perfusion by targeting dopaminergic receptor sites
What would a dose of 2-10 mcg/kg/min of dopamine be used for?
Increased rate and force (chrontrope,inotrope) of heart by targeting beta 1 receptor sites
What would a dose of 10-20 mcg/kg/min of dopamine be used for?
Vasoconstriction by targeting alpha receptor sites
If you have a drop in cardiac output, what needs to happen in order to maintain adequate blood pressure?
Vasoconstriction
If a patient is found unresponsive in cardiac arrest scenario, what is your order of operations?
CAB, circulation, airway, breathing
What could a difference between central and peripheral pulses indicate?
Internal bleed
What are palpitations?
Sensation of an abnormally fast or irregular heartbeat, except after extreme exertion. May report feeling like their heart skipped a beat
What are beta blockers used for?
Relief for angina, lower blood pressure, prevent recurrence of MI. All end in -lol
What is digitalis used for?
CHF, rapid atrial arrhythmias. Acts by increasing the strength of cardiac contractions, improving CO
What 3 major classes of drugs are used to treat pain from angina?
Nitrates, beta blockers, calcium channel blockers. All of them diminish myocardial oxygen demand
How long does it take nitro to work?
3-5 min
What is another good use for nitro?
Causes significant vasodilation. Can be useful for treatment to pulmonary edema secondary to left side heart failure.
What is a common side effect of nitro?
Throbbing headache
When a patient tells you they take nitro, what are two important questions to ask?
Did they take it today, how much? & did it relieve the pain? (Could be expired)
What medication could you use for a dysrhythmia caused by the toxic effects of digitalis?
Dilantin - also used for seizures
What is orthostatic hypotension?
An experience a patient has when moving from a recumbent to a sitting or standing position where they feel giddy. Occurs because of their antihypertensive medication and you should check their blood pressure before you have them move so you don’t get a false reading
What are pradaxa and plavix used for?
Pradaxa is an anticoagulant medication and plavix is a anti platelet medication. Both are used in managing myocardial infarction
What is S1?
Beginning of ventricular contraction when the mitral and tricuspid valves close
What conditions can diminish s1?
Obesity, emphysema, cardiac Tamponade
What is s2?
Occurs near the end of ventricular contraction when the pulmonary and aortic valves close
What is s3?
Heard in children and young adults, in older adults it signifies heart failure
What does an opening snap indicate?
A noncompliant valve
What is ejection click?
High pitched sound occurring after s1. May indicate dilated pulmonary artery or septal defect
What is a pericardial friction rub?
To and fro sound that can be heard in systole and diastole. Heard in patients with pericarditis
What is a murmur?
Ambiguous sound associated with turbulent flow through the heart valves
What is pericardial knock?
High pitched sound during diastole that indicates a thickened pericardium that is limiting how far the ventricle can expand during diastole phase
What can an irregular pulse indicate?
A disturbance in cardiac rhythm
What does a weak thready pulse indicate?
Reduction in cardiac output
What is pulse deficit?
When the palpated radial pulse is less than the apical pulse rate; reported numerically as the difference between the two
What is pulsus alternans?
Pulse alternates between strong and weak beats and typically represents left ventricular systolic damage
How do you look at the right side of the heart?
Move V4 to the right
How do you look at the posterior of the heart?
Move v4,v5,v6 to the back
What is the j point?
Where the ST segment begins, ends at beginning of t wave
In sinus dysrhythmia, what is the reflex that increases the heart rate because of increased filling pressures during inspiration?
Bainbridge reflex
What is sinus arrest?
Occurs when the SA node fails to initiate an impulse, eliminating the p wave, QRS, and or t wave for one cardiac cycle
What can cause sinus arrest?
Ischemia of the SA node, increased vagal tone, carotid sinus massage, and use of drugs such as digitalis
What is sick sinus syndrome?
Encompasses a variety of rhythms that involve a poorly functioning SA node and is common in elderly patients, normally goes back and forth between bradycardia and tachycardia. Some patients experience syncopal or near syncopal episodes, dizziness, and palpitations. Other patients are asymptomatic.
How do you distinguish an idioventricular rhythm?
Under 20-40 beats, no p waves
How do you differentiate between an agonal rhythm and an idioventricular rhythm?
An idioventricular rhythm may have a palpable pulse, an agonal will not
What is Wolff-Parkinson-white syndrome?
A preexcitation disorder that is characterized by short PR interval, widened QRS, and presence of a delta wave
What is the process of dissolving blood clots called?
Fibrinolysis
What is pericarditis and how will it present with a patient?
Inflammation of the pericardial sac as a result of an infection (bacterial, viral, or fungal) or trauma. Patients will present with positional chest pain that is often alleviated by sitting forward, SOB, and recent HX of infection or fever. Characterized by slight ST elevation and a down sloping PR segment. Can lead to pericardial effusion which can develop into pericardial Tamponade. Tx is pericardialcentesis. Will hear a to and fro sound in systole and diastole which is defined as a pericardial friction rub.
What will j waves or Osborne waves on an ECG indicate?
Severe hypothermia
What do tall and sharply peaked T waves indicate?
Hyperkalemia
What does an ECG with a flat or absent t wave and a u wave indicate?
Hypokalemia
What is brugada syndrome?
Genetic disorder involving sodium channels of the heart common among Asian males in their 40’s or 50’s. Presents with sudden onset of syncope or cardiac arrest. Characterized by incomplete RBBB.
What is the contraindication for a carotid sinus massage?
Presence of Bruits in the carotid arteries
What is prehospital treatment for a thromboembolism?
Supportive care
What occurs in angina pectoris?
Occurs when the supply of oxygen to the myocardium is insufficient to meet the demand. As a result, the cardiac muscle becomes ischemic and switches to anaerobic metabolism
What is prinzmetal angina?
A coronary artery spasm that is common in women in their 50’s
How will a patient present in left sided heart failure?
Shortness of breath when lying down, cheyne stokes respirations, patient will be extremely restless and agitated, high BP, crackles, wheezes, pink frothy sputum. CPAP will be an effective tool
What are two good medications for left sided heart failure?
Lasix, nitro
How will right sided heart failure present?
Usually occurs because of left sided heart failure or as a result of PE or COPD. Patient will have JVD, peripheral edema. Make sure you assess jugular veins in the semi fowler position. Treatment is to make the patient comfortable.
How can the development of a cardiac Tamponade (gradual vs. trauma) affect what the patients chief complaint will be?
If onset is gradual like in pericarditis the patient may report of dyspnea and weakness. If the cause is traumatic the chief complaint will be chest pain
For cardiac Tamponade, what is becks triad?
- ) narrowing pulse pressure
- ) muffled heart tones
- ) JVD
What is the way you differentiate between cardiac Tamponade and a tension pneumothorax?
In cardiac Tamponade, breath sounds will all be equal and the trachea will be midline because the lungs are not affected
When will cardiogenic shock occur?
When 40% or more of the left ventricle has been infarcted.
What are the symptoms of cardiogenic shock?
Difficulty breathing, extreme fatigue, general malaise
What will a patient complain of if the underlying issue is a dissecting aneurysm?
The worst pain I have ever experienced, a ripping or tearing sensation, like a knife. Pain will come on suddenly and is located anterior chest or in the back between the shoulder blades.
How can you differentiate between the presentation of an AMI to that of a dissecting aneurysm?
AMI will be accompanied by nausea or weakness and tends to be a more gradual “crushing” pain related to pressure. Dissecting aneurysms will be more of a “stabbing” pain and will be sudden. Also the back is involved with aneurysms whereas it is not with AMI’s
What should you suspect in a patient who is male, 50-60’s with a sudden onset of abdominal or back pain?
Abdominal aortic aneurysm
How will a patient with a AAA present and complain of?
Believe they may have pulled a muscle in their back. Pain will radiate to their thigh or groin, will have an urge to defecate, pulsatile mass palpable in the abdomen.
What treatment should you consider for AAA?
Apply but do not inflate MAST, lactated ringers
What are common symptoms of a hypertensive emergency?
Throbbing headache, dizziness, epistaxis, tinnitus, blurred vision
How is a hypertensive crisis defined?
A sudden rise of BP greater than 200/130
When MAP exceeds 150 in a hypertensive crisis, what occurs?
Pressure breaches blood-brain barrier and fluid leaks out, increasing intracranial pressure
What is the goal of treatment in a hypertensive emergency?
Lower BP in a gradual and controlled manner during a 30 to 60 minute period so cerebral flow is restored to normal
How is endocarditis caused and who usually gets it?
Exclusively caused by staph or strep infection. Most likely to get it are patients who abuse intravenous drugs and patients who have prosthetic heart valves
What is rheumatic fever?
Inflammatory disease caused by streptococcal bacteria strains. Can cause stenosis of the mitral or aortic valve leading to heart complications.
What is scarlet fever?
Disease caused by the same bacteria for strep throat. Characterized by fever, rash, and “strawberry” tongue. Usually prevalent in patients younger than 1 year old.
What two conditions could electrical alternans be caused by?
Pericardial effusion or cardiac Tamponade
What 3 things could cause a wandering atrial pacemaker?
COPD, pneumonia, asthma
What is sick sinus syndrome?
Older heart where exercise causes HR to spike too high and when the heart tries to compensate, it drops it too low
What are ostea?
Openings to coronary arteries
What does a 2-5 dose of Dopeamine cause?
Renal response
What does a 5-10 dose of Dopeamine cause?
Exclusively sympathetic
What does a 10-20 dose of Dopeamine cause?
Positive inotrope
What is a vector?
Direction of electrical impulse
What is axis?
Way to measure the greatest amount of electrical activity
What is long QT syndrome?
A genetic condition that causes the heart to be bradycardic, pt. Will die at a young age
What is the number 1 cause of PVC’s?
Hypoxia
What are the three irregularly irregular rhythms?
- ) AFIB
- ) multi focal atrial tachycardia
- ) wandering atrial pacemaker
What causes Sinus arrhythmia?
Caused when the diaphragm touches the apex of the heart during inspiration causing the bambridge reflex
What can cause PR depression?
Pericarditis (tachycardia, ST elevation, pain is positional)
What type of block is it if the PRI changes beat to beat?
3rd degree
If a PVC is not premature than what is it?
Escape beat
What is the number one cause of left ventricular hypertrophy?
Hypertension, failure occurs with more and more pulmonary edema
What is the number one cause of right ventricular hypertrophy?
Cor pulmonale
What are your precordial leads?
V1-V6
What do biphasic t waves indicate?
Wellens syndrome, a pattern of deeply inverted biphasic t waves in v2-3 which indicates stenosis of the left anterior descending artery
Where does the heart receive its blood from?
Coronary sinus, it drains into the right atrium
What are your reciprocal changes?
II,III,aVF - 1,aVL
v1,v2 - v7,v8,v9
What does ST elevation indicate on an ECG?
Indicates where the issue is occurring
How do you identify bundle blocks?
Look in v1 for the waveform with the greatest vector. If it is on the left or right it is a LBBB or a RBBB.
Wide and up = RBBB
Wide and down = LBBB
What do tombstone T’s indicate?
Massive left side attack
Wide QRS?
Think issue with potassium
How do you determine axis deviation?
Look at 1 and aVF terminal waves, which one has the greatest height or depth? That is your axis deviation
Down in 1, down in F =?
Extreme right axis deviation
Down in 1, up in F =?
Right axis deviation
Up in 1, down in F =?
Left axis deviation
Up in 1, up in F =?
Normal, no axis deviation
What are the main causes of right axis deviation?
Right ventricular hypertrophy, dextrocardia, COPD
What are the main causes of left axis deviation?
Left ventricular hypertrophy, CHF, MI
What disorder causes the body to assume the temperature around it?
Hypothyroidism
What condition will cause there to be a yellow cast around everything in vision?
Digitalis toxicity
What should you do after ROSC?
12 lead, consider hypothermic treatment
If you convert a patient in a cardiac dysrhythmia with lidocaine, what else must you do?
Use a lidocaine drip because the half life is so short. 2g in 500 mL making 4 mg/mL yielding 1-4 mg/min
After the patient comes out of an unstable cardiac dysthymia where there is clinical death, what should you do?
Administer 1 liter of fluid, continue CPR for 2 min
What is the dose for Dopeamine when mixing it up? For algorithm use.
800 mg in 500 mL yielding 1600 mL
What does ST elevation in 1 and AVL indicate?
High lateral wall MI
What are the key characteristics of a PVC?
QRS will be wide and bigger than the rest
What are the key characteristics of a PAC?
Narrow, normal, but early
What are the key characteristics of a PJC?
QRS will look different from the rest
What is the normal range for bicarb levels in the body?
23-29
If you have a pacemaker failure, what is your next action?
TCP
What is the dose for an Epi drip?
2mg/500 mL
What could pulsus alternans indicate?
Common in CHF
What should you consider if there is decreased pulse on one side?
Aneurysm
