Chapter 16: Cardiovascular Emergencies Flashcards
Path of impulses in the heart
Brain, SA node, atria, AV node, bundle of His, Purkinje fibers, ventricles
Automaticity
Feature of cardiac muscle that allows cells to contract without a nerve source.
Stroke volume
Amount of blood ejected by each ventricular contraction
Cardiac output
Volume of blood going through the circulatory system in one minute. SV times heart rate.
Subclavian arteries
Supply blood to upper extremities, branch into brachial arteries
Descending aorta
Divides into right and left iliac arteries at the umbilicus. As they enter the legs, they branch into femoral arteries, which branches into anterior and posterior tibial arteries at knee level.
3 components of perfusion
Heart, blood vessels, blood
Tachycardia
Doesn’t allow enough time for heart to refill completely
Ischemia
Decreased blood flow. Often a cause of chest pain.
Infarction
Death of tissue
Occulism
Blockage
Lumen
Inside diameter of artery
Atherosclerosis
- Calcium and cholesterol build up and form blockages in vessels. Eventually forms an occulism.
- Plaque can develop a crack, which activates blood clotting. Blocks lumen of artery or forms a thromboembolism which causes hypoxia below it.
- Blockage in a coronary artery is an AMI
Atherosclerosis risk factors
Smoking, high blood pressure, high cholesterol, high blood glucose, obesity, older age, family history, sex (male).
Acute Coronary Syndrome
- Describes a group of symptoms caused by myocardial ischemia.
- Angina pectoris- chest pain from lack of oxygen, symptom of acute coronary artery disease. Lasts less than 15 minutes. Crushing pain under sternum, radiating to jaw, arm, back, abdomen, nausea, sob
AMI Symptoms
Sudden onset of weakness, nausea, and sweating without an obvious cause. Chest pain or pressure that is crushing/squeezing and does not change with each breath. Pain or pressure in lower jaw, abdomen, or neck. Shortness of breath, irregular heartbeat, syncope, nausea, pink frothy sputum. In older people or women, most common symptom could be fatigue or nausea.
Ventricular tachycardia
Heart rate is 150-200 bpm. Electrical activity starts in ventricles and doesn’t allow the left ventricle to fill with blood. Blood pressure falls and pulse can be lost.
Ventricular fibrillation
Disorganized quivering of ventricles that doesn’t allow blood to be pumped. Requires defibrillation. Begin CPR to prevent asystole.
Cardiogenic Shock
Often caused by AMI. Heart lacks power to force blood through circulatory system, tissues don’t get enough oxygen. Can occur immediately to 24 hours after.
Congestive Heart Failure
- Occurs when ventricular myocardium is so damaged it can’t keep up with blood flow from the atria.
- Can occur any time after a myocardial infarction or as a result of hypertension.
- Causes increased heart rate, enlarged left ventricle, and pulmonary edema.
Shock symptoms
- Anxiety/restlessness/air hunger
- Pale, cool, clammy skin
- High pulse that can become weak or irregular
- Rapid/shallow breathing, nausea, decreased body temp
- Low blood pressure indicates late stage shock
Shock treatment
Give oxygen, assist ventilations, comfortable position, cover with blankets
CHF Symptoms
- Breathing is easier when sitting up due to pulmonary congestion
- Agitation, chest pain can be present
- Distended neck veins, swollen ankles from dependent edema.
- Accessory muscle use, pale cyanotic or sweaty skin
- Fluid creates rales
CHF Treatment
Give oxygen, might need CPAP, sitting up, might be able to give nitroglycerin, gather any meds, transport.
Hypertension
Any blood pressure over 140/90. Becomes an emergency if systolic is higher than 180.
Hypertensive Emergencies
- Indicated by severe headache, strong pulse, ringing in ears, nausea, dizziness, warm skin, nosebleed, AMS, sudden pulmonary edema.
- Can lead to hemorrhage. Transport immediately, monitor bp, keep head elevated.
Dissecting aortic aneurysm
- Inner layers are separated, and blood flows between them at high pressures. Causes aorta to rupture, leading to massive hemorrhage and sudden death.
- Sx: Very sudden and severe sharp or tearing back or chest pain, difference in bp between arms, diminished bp in lower extremities.
Patient Assessment: Scene size up
Ensure safety. Do not become fixated on a specific illness or condition.
Patient Assessment: Primary Assessment
- Determine if responsive. If not, start CPR and AED.
- Responsive patients should have an open airway
- Listen to breath sounds, determine rr, find pulse ox, give oxygen
- PE might require CPAP.
Patient Assessment: History Taking
SAMPLE, ask about symptoms and possible trauma
Patient Assessment: Secondary Assessment
Vital signs, evaluate circulatory and respiratory systems
Emergency Medical Care for chest pain
- Proper positioning- some patients can’t be supine
- Give oxygen to reach 95-99% oxygenation
- Can give aspirin or nitroglycerin, but first determine allergies and history of internal bleeding.
Contraindications of nitroglycerin
Systolic blood pressure less than 100, head injury, use of erectile dysfunction drugs within 24-48 hours, or max dose has been given.
Nitroglycerin
Relieves pain of angina. Increases blood flow to heart, reduces workload of heart, relaxes blood vessel walls and dilates coronary arteries.
How to administer nitroglycerin
Get an order from medical control, wear gloves, administer sublingually.
3 lead ECG
One on each shoulder, one on each side of lower abdomen near hips.
12 lead ECG
- 4 used for limb placement
- v1- 4th intercostal space right sternal border
- v2- 4th intercostal space left sternal border
- v3- Between v2 and v4
- v4- 5th intercostal space, midclavicular line
- v5- lateral to v4, anterior axillary line
- v6- lateral to v5 at midaxillary line
Don’t place a limb electrode over a bone.
Don’t place AED patches over a
Pacemaker
Implantable defibrillator
Delivers shocks as needed
External defibrillator vests
Works the same way as an AED, should not be removed unless they interfere with CPR.
LVAD
Assist the left ventricle, shouldn’t have to worry about them.
Cardiac Arrest
- Complete cessation of electrical or mechanical activity, or both.
- Indicated by absence of a pulse
- Apply AED only if patient is unresponsive and has no pulse.
Chain of survival (cardiac arrest)
Recognition of early warning signs, immediate CPR, rapid defibrillation, basic and advanced EMS, ALS and post arrest care.
Emergency Care for Cardiac Arrest
- Apply AED pads to the right of the sternum just below the clavicle, other on the left lower chest with the top below the armpit.
- If you feel a pulse, patient has experienced return of spontaneous circulation (effective blood flow). Continue to monitor and give oxygen.
