emt 20

Cardiovascular system

made up of the heart, blood vessels, and blood

Cardiovascular system purpose

to perfuse cells of the body, relies on a constant supply of O2 to fuel metabolism and power functions 

Structures/functions of the CV system

• Blood composition (red, white, plasma, platelets)

• Blood flow through heart chambers (atria & ventricles)

• Blood flow through arteries, veins, etc.

• Blood circulation between heart and lungs and heart and the rest of the body

Cardiac conduction system mechanism

electrical charge is created, energy passes cell to cell via special pathway and distributes, spreads to heart cells and stimulates cells contracting the heart (pushing blood)

Coronary arteries

give the heart its blood supply

acute coronary syndrome

aka cardiac compromise, refers to anytime blood supply to heart cells is blocked or disrupted (immediate transport)

2 ways ACS is formed

1. Abruptly when a clot blocks the coronary arteries causing MI

2. Overtime when coronary artery is narrowed due to plaque buildup

Ischemia

hypoxic condition when heart cells don't have enough O2 to conduct metabolism  

Ischemia effects

skin + bones can endure long periods of ischemia, heart + brain cells die quick and can’t be revived. Most damage can reverse by restoring perfusion

Recognizing ischemia

seeing inability to carry out simple functions (ex. Movement or speech)

ACS main symptom

chest discomfort/ pressure or squeezing. Discomfort can radiate to the jaw, neck, arm or upper abdomen

ACS w/out pain

common in older patients, women, and diabetics

Dyspnea

shortness or breath, associated w heart ischemia along w nausea, vomiting, and syncope

ACS patient characteristics

brady/tachycardia, sweaty/anxious, palpitations, general weakness

ACS patient assessment

perform primary assessment, history and physical exam, examine chief complaint via OPQRST, get past medical history (SAMPLE), and take vitals

ACS signs of discomfort

grabbing/clutching center of the chest (levine sign), sweating, pale/grey skin, anxious/restless

ECG mechanism

sticky electrodes placed on the chest to sense hearts electrical activity, electrodes connect via wire cardiac monitor, activity is measured/displayed on monitor

Placing ECGs

only 10 ECGs are placed on the chest, each is labeled with where it should be placed and color coded with proper positioning

Treating ACS patients

place in position of comfort, determine if O2 should be given based on O2 sat

Respiratory failure/apneic patients O2

give high concentration O2 via BVM ventilations or pocket face mask

ACS immediate transport signs

no history of cardiac problems/history of cardiac problems w no nitroglycerin, or systolic below 90mmHg

Do NOT give ACS patients aspirin when

cannot swallow, taken 325mg aspirin in last 6 hours, aspirin allergy, history of GI bleeding (contact med control), or taking prescribed blood thinner

Give nitroglycerin to ACS patients when

chest discomfort w/ history of cardiac problems, nitro is prescribed + with them, systolic BP 90+, not taken ED drugs within 48-72 hours, med direct approves

When to repeat nitro dosage

after 5 mins IF patient experiences little/no relief, systolic BP remains 90+, med direction approves, no more than 3 doses

Nitro actions and side effects

relaxes blood vessels + decreases heart’s workload, can cause hypotension, headaches, and pulse changes 

Coronary artery disease

conditions that narrow or block the arteries of the heart

CAD

plaque build up on the inner/middle artery walls, narrowing inner vessel diameter and restricting blood flow

Who is at risk of CAD

heredity and age (cannot be changed) high BP, obesity, lack of exercise, elevated blood levels of cholesterol, triglycerides, and smoking (can be changed)

Angina pectoris

chest pain (ACS sign) when blood supply to the heart is reduced and part of the heart is not receiving enough O2

Angina pectoris symptoms

symptoms diminish when patient stops exertion, hearts demand for oxygen returns to normal

• attacks lasts seldom 5 minutes max

Nitroglycerin with angina pectoris patients

sign patient has history w this condition, nitro dilates veins so more blood stays in bodys viens and less comes back to the heart so heart does not have to work as hard

Angina pectoris vs acute MI

same symptoms making but angina symptoms can be solved w rest, acute MI symptoms can't.

Assume angina patients have acute MI until proven otherwise 

Angina pectoris treatment

same as ACS, consider O2, nitro if indicated & prescribed, aspirin, 12-lead ECG

Aneurysm

dilation/ballooning of a weakened section of an artery wall

Occlusion

blockage of an artery due to fatty deposits (build up)

Thrombus

clots/plaque attached to the inner wall of an artery, can block blood flow and cause occlusion 

Ebolism

when blood flow moves a clot causing it to block a vessel

Clot blockage effects

deprives tissue beyond the blockage of oxygen causing it to die, may be fatal in cases of heart or brain 

Acute myocardial infarction (AMI)

(heart attack for lay ppl) blockage of a coronary artery by formation of a thrombus or embolism 

AMI causes

when blood flow to the heart is interrupted and myocardial cells begin to die, rarely caused by aneurysm 

Blood occlusion during MI effects

1. Ischemia (heart cells not having enough O2 to conduct metabolism) 2. Dysrhythmia (disruption of heart rate and rhythm)

Dysrhythmia cause

when electricity is distributed abnormally through the heart causing harmful changes in rate, rhythm, and pumping ability 

Mechanical problems caused by MIs

During MI, cells die from hypoxia & loose function, if blockage effects enough cells, the hearts pumping can be effected

Cardiogenic shock

when multiple MI’s diminish heart’s function to an unsafe level, results in acute inability of the heart to function mechanically, deadly, leads to dramatic BP drop

Fibrinolytics

medications that dissolves clots in the arteries caused by MI’s, the earlier administrated, the easier to dissolve the clot

Balloon angioplasty

inserting a catheter into clogged artery and inflating balloon to reopen circulation

most effective way to unclog arteries  

Medication after an MI

aspirin everyday and beta blocker (group of medications that slow + weaken heart beat)

Secondary assessment for MI patients

identifies signs/symptoms of ischemia or an occluded coronary vessel

Heart failure

when heart is unable to pump blood with normal efficiency. means one or both ventricles cant fill or pump enough to satisfy the c-vascular system, commonly found in secondary assessment

Heart failure v cardiac arrest

cardiac arrest = heart cannot pump blood heart failure = heart pumps blood but ineffectively

Heart failure effects

decreased perfusion, struggle w exercise related tasks, limited ability to compensate challenge, fluid backup 

Ventricle(s) failing to eject enough blood

leads to pressure build up in vessels and JVD due to pressure increase.

• body may try to rid excess fluid by pushing it to capillaries around the liver causing pedal edema

Pedal edema

caused by JVD and ventricles failing to eject enough blood

Left ventricle failure

pressures pulmonary vein, pushing fluid to capillaries/alveoli, eventually collapsing tiny air sacs and impairs ability to diffuse O2/CO2

Pulmonary edema

fluid build up in the lungs, first seen in respiratory distress, identified w crackle sounds in lungs

Arteries affected by aneurysm

can occur in any artery but common in brain, chest, abdomen

Aneurysm mechanism

weakened area of an artery expands and dilates outward under the pressure of normal blood flow.

• when a weak section of the artery bursts, life threatening bleeding can occur

sign of pulmonary edema

lung crackles

nitro contraindication

head injury

dissecting aortic aneurysm

inner layers of aorta become separate

most common aneurysm sites

aorta and brain

nitro route

sublingual

diastolic BP

pressure in arteries between contractions

hearts job

circulate blood