EMER 110 Cardiac and Respiratory Theory Flashcards
Deep Vein Thrombosis (DVT)
A thrombosis is a blood clot that remains attached to a vessel wall.
what is the cause of Deep Vein Thrombosis (DVT)
Intimal irritation, roughening, inflammation, traumatic injury, infection, low blood pressures, or obstructions that cause blood stasis Inflammation is the usual cause of DVT
causes of DVT
History of trauma Sepsis Stasis or inactivity Recent immobilization Pregnancy Birth control pillsMalignancy Coagulopathies SmokingVaricose veins
signs and symptoms of DVT
Pain Edema Increase temp extremity Erythema Tenderness
Atherosclerosis
Fatty build up Affects the inner lining of the aorta, cerebral, and coronary blood vessels. Abnormal thickening and hardening of vessel walls
what is Atherosclerosis caused by
Caused by soft deposits of intra-arterial fat and fibrin which harden over time
Risk Factors for atherosclerosis
Hypertension (HTN) Cigarette smoking: thickens vessel walls making it hard for blood to pass through Diabetes High serum cholesterol levels Lack of exercise Obesity Family history of heart disease or stroke Male sex
Effects of Arteriosclerosis
loss of elasticity in vessel walls Partial obstruction of vessel lumen (Ischemia) Complete obstruction of vessel lumen (Infarction, Necrosis) Thrombosis Embolism (Obstruction, Infarction (Heart and Brain) —Infarction: complete obstruction Aneurysm (Rupture, Exsanguination) Vessel calcification (Rigidity, Rupture)
Aneurysm
“dilation of a vessel” Artery wall weakness
most common cause for AAA
Atherosclerosis
Signs and Symptoms of a ruptured aneurysm
Shock Pain, usually describe as sharp stabbing in nature. Back pain Difference in blood pressure between arms Absent radial or femoral pulse Mottling of extremities below aneurysm modeling: spider veins, bluish white skin absent radial or femoral pulses
Hypertension
Known as lanthanic (silent) disease Characterized by a consistent elevation of systemic arterial blood pressure Often defined by a resting BP consistently greater than 140/90 mm Hg
Risk Factors of hypertension
Family history Advancing age Gender (men younger than 55, women older than 74): structural changes of vessels Black race: social status High dietary sodium intake Glucose intolerance: higher cholesterol Cigarette smoking Obesity Heavy alcohol consumption Low dietary intake of potassium, calcium and magnesium
Pathophysiology of hypertension
Damages walls of systemic blood vessels Prolonged vasoconstriction and high pressures with in the arteries and arterioles stimulate the vessels to thicken and strengthenEnd result is a permanently narrowed blood vessel
Treatment Plans Arteriosclerosis Peripheral Vascular Disease Hypertension Deep Vein Thrombosis Aneurysm
*symptomatic only
Endocarditis
Inflammation of the inner lining of the heart, and/or heart valves
causes of endocarditis
Can be caused by either bacteria or virus, bacteria being the most common
risk factors of endocarditis
Acquired valvular heart disease (mitral valve prolapse) Implantation of prosthetic heart valves Congenital lesions Previous attack Male gender Intravenous drug use: dirty needles Long term indwelling catheterization
Signs and Symptoms of endocarditis
May involve a number of organ systems Classic findings Fever Cardiac murmur Petechial lesions of skin, conjunctiva, and oral mucosa Chest pain- SOB
myocarditis
Is an inflammation of the heart muscle (myocardium) Results from infection (bacteria or viral) or toxic inflammation (drugs or toxins from infectious agents) Cocaine users are 5x more likely to get it
myocarditis causes
Chest infection Auto immune disease Fungal viral infection
signs and symptoms of myocarditis
Flulike Pain in epigastric region or under sternum (substernal) Dyspnea Cardiac arrhythmias Stabbing chest pain
pericarditis
Inflammation of the pericardium, two thin layers of a sac-like tissue surround the heart, hold it in place and help it work. Normally, a small amount of fluid keeps the layers separate so that there’s no friction between them.
Signs and Symptoms Pericarditis
Low cardiac output Low SPO2 Chest pain
causes of pericarditis
Trauma Heart attacks
Acute Coronary Syndrome (ACS)
refers to distinct conditions caused by a similar sequence of pathologic events involving abruptly reduced coronary blood flow
Acute Coronary Syndrome (ACS) conditions
Unstable Angina (UANon-ST-segment elevation myocardial infarction (NSTEMI), ST-segment elevation myocardial infarction (STEMI)
Ischemia
Lack of oxygen to the tissues ST depression or T inversion
Ischemic Heart Disease
Myocardial ischemia is usually the route of the blockage or gradual narrowing of one or more of the coronary arteries by atheromatous plaque. Narrowing or blockage of a coronary artery can disrupt the oxygen supply to the area of the heart supplied by the affected vessel. If the cause of the ischemia is not reversed and blood flow restored to the affected area of the heart muscle, ischemia may lead to cellular injury and ultimately, cellular death
Clinical Features of Ischemic Heart Disease
retrosternal chest pain, pressure, heavinesssqueezing lasting 10 minutes or longer that usually occurs at rest or with minimal exertionCan be accompanied by angina equivalents such as unexplained new-onset or increased exertional dyspnea, unexplained fatigue, diaphoresis, nausea/vomiting, or syncope
atypical presentation of Ischemic Heart Disease
may include pleuritic chest pain, epigastric pain, acute-onset indigestion, or increasing dyspnea without chest pain. Atypical presentations are most often observed in younger(25 to 40 years of age) and older(over 75 years) patients, women, and patients with Diabetes Mellitus, chronic renal insufficiency, or dementia
what does schema lead to
Injury prolonged ischemia ST elevation
infarct
death of tissue may or may not show in Q wave
angina Three types:
Stable Angina (Exertional Angina) Unstable Angina (Preinfarction Angina) Prinzmetal’s Angina
Prinzmetal’s Angina
Vasospastic angina: no blockage or clot just spasm of segment of coronary arteryCause: cocaine Treatment: nitro
Angina
Imbalance between myocardial O2 supply and demand choking pain in the chest” Burning Tightness Pressure Crushing heavy
The coronary arteries can spasm as a result of :
Exposure to cold weather Stress Medicines- Anti-migraines, Chemo, Antibiotics Smoking Cocaine use
Myocardial Infarction
Sudden and total occlusion or near‐ occlusion of blood flowing through an affected coronary artery to an area of heart muscle Results in ischemia, injury, and necrosis of the area of myocardium distal to the occlusion.
If blood flow is not restored to the affected artery
myocardial cells within the sub-endocardial area begin signs of injury within 20 to 40 minutes.
ACS Management/ Treatment
Reduce physical activity, calm reassurance O2 if WOB increased and SPO2 less than 94%, if pale, if SOB If clinically indicated ASA 160-325mg PO –81mg X2= 162mg 3 Lead followed by 12 Lead ECG noted IV BEEFORE NITRO –0.4mg spray –1 every 3-5 mins –At 3 min mark vitals and re assess If clinically indicated, Nitro 0.4mg SL, titrate to effect Consider calling ALS Notify receiving hospital if ST elevation
ACS CALL vs NON ACS CALL
ACS CALL Heavy, burning tight NON ACS CALL Sharp pain Increases with palpation Increase with inspiration
angina signs and symptoms
“choking pain in the chest” Burning Tightness Pressure Crushing Heavy Radiates Lasts less than 20 min Sob Occurs with activity Is better with rest
UNSTABLE angina signs and symptoms
Lasts longer than 20mins Can occur at rest
MI: STEMI, NSTEMI signs and symptoms
At rest Doesn’t get better Shock symptoms –Nausea vomiting –Pale cool clammy
Cardiomyopathies
Diverse group of diseases that affect the myocardium Most result from underlying disorders In response to injury, the heart may undergo dilation or hypertrophyCardiomyopathies are incurable diseases and the only hope is heart transplantation
Cardiomyopathies are divided into three forms:
Dilated Cardiomyopathy Hypertrophic cardiomyopathy Restrictive cardiomyopathy
cardiac outputstroke volumeFormula
Cardiac output (CO): amount of blood ejected by each ventricle in 1 minute Stroke volume (SV): amount of blood pumped by each ventricle in 1 beat (mL/beat) CO=SV X HR 70ml/beat x 75 bpm+ 5250mL/min
Factors that affect CO
- Heart rate 2. Preload: 3. afterload:4. Contractility:
define preload and after load
Preload: amount of blood entering ventricles @ diastole (rest) à nitro decreases preload afterload: resistance ventricles have to overcome to circulate blood à decreasing afterload decreases back up into the lungs
Pulmonary Edema
Swelling within the lungs Sign of left sided CHFDecrease of output to left side of heart
One of the most common causes of pulmonary oedema is
left ventricular failure from an acute MIOther cause are inhaled toxins, infections, and sometimes trauma and altitude changes
Pulmonary Edema Signs and Symptoms
In early pulmonary edema you will hear late inspiratory crackles at the lung apices. These crackles are caused by rapid expansion of collapsed alveoli as they reach maximum inflation As pulmonary edema worsens you will hear more proximal crackles in lung fields As fluid migrates into larger more central airways and mix with mucus the crackles become more coarse sounding. As lungs fill up frothy pink sputum may appear, which an ominous sign. Happens acutely
Congestive Heart Failure
heart failure may present acutely as a result of acute pump dysfunction from an mi Heart is unable to pump powerfully enough or fast enough to empty its chambers. Blood backs up into the systemic circuit, the pulmonary circuit, or both.
Left sided CHF
Pumps blood to body Pulmonary hypertension Back up into the lungs Crackles in lungs SOB Left sided heart failure is most commonly caused by an AMI and chronically by continued hypertension.
Left-sided heart failure signs and symptoms
Extreme restlessness and anxiety, confusion and agitation Severe dyspnea, tachypnea, tachycardia Hypertension or hypotension Crackles and/or wheezes Frothy pink sputum in severe cases
Right sided CHF
Pumps blood to lungs JVD Pedal edema Pitting edema SOB
Right-Sided heart failure Signs and Symptoms
Jugular vein distention Pedal/pitting edema
Heart Failure Management
Position of comfort, most often high fowlers If clinically indicated administer nebulized sympathomimetic/anti-cholinergic If clinically indicated initiate Continuous Positive Airway Pressure (CPAP) Consider ALS intercept If clinically indicated administer SL nitroglycerine
Pulmonary edema treatment
Crackles: nitro CPAP Wheezing: Ventolin and Atrovent –Call ALS if Combivent doesn’t work
Nitro for pulmonary edema
No chest pain and no nitro prescription –> call med control for orders No chest pain- nitro prescription –>give nitro Chest pain –> give nitro
Causes for pulmonary edema
Cardiogenic Noncardiogenic
Cardiogenic Noncardiogenic
Cardiogenic 1. Left sided failure 2. Systemic hypertension Noncardiogenic -Toxins -Lung infections -Sepsis
Pneumonia Vs Pulmonary Edema
–Pulmonary edema: cause by Left heart failure Normal HR Febrile course Crackles Wheeze May or may not be productive cough- punk or white History of CHF Cardiac CP- won’t increase with inspiration —Pneumonia: infection Fast HR Fever thick Crackles Wheeze Productive cough- green or dark yellow History of pneumpnia Sharp CP Cp increase with inspiration/coughing
Cardiogenic Shock
Heart is so severely damaged that it can no longer pump a volume of blood sufficient to maintain tissue perfusion. When 25% of the left ventricular myocardium is involved When 40% or more of the left ventricle has been infarcted (tissue death) High mortality rate
Signs and symptoms of cardiogenic shock brain
Altered LOC Coma Lethargy Possible stroke
Signs and symptoms of cardiogenic shock lungs
SOB Accessory muscle use Stats less than 90 Tachnyepia
Signs and symptoms of cardiogenic shock heart
Increase HR Decrease BP Arythmias MI
Signs and symptoms of cardiogenic shock skin
Cool Clammy Delayed cap refill
Management of Cardiogenic Shock
Focuses on improving oxygenation and peripheral perfusion Secure the airway and administer 100% supplemental oxygen. Advanced airway necessary if the patient is comatose. Place the patient in a supine position. IV with normal saline
Frank-starling mechanism
One characteristic of cardiac muscle is that when it’s stretched a contract with greater force
systematic vascular resistance leads to
a higher after load in the cardiac output can drop or heart rate has to work harder to maintain the same cardiac output which increases oxygen demand
- Changes in contractility may be induced by
medication’s that have a positive or negative inotropic effect
- Nervous system controls regulate the
contractility of the heart from beat to beat
- Positive chronotropic effect
how hard can increase its cardio output by increasing the number of contractions per minute (HR)
- Pacemaker
the area of conduction tissue in which the electrical activity arises at any given time
- AV node
is gatekeeper to the ventricles o In 85-90% of humans blood supply comes from the branch of the RCAo 10-15% of ppl it comes from the left circumflex artery
- Electric impulses from SA node take how may secs to read AV node
o.o8secs
- The conduction is delayed in the AV node for approximately how many secs
0.12sec
- It takes approx. how many sec for an electrical impulse to spread across the ventricles
0.08
what happens with ions during depolarization
depolarization sodium and calcium ions rush into cell causing inside of cell to be positive
what happens with ions during repolarization
the sodium and calcium channels close and potassium channels open allowing rapid escape of potassium ions from the cell
- Refectory period
period when the cell is depolarized or in the process of repolarizing
- Absolute refractory period
the cell is still highly depolarized and a new action protentional cannot be initialed
- Relative refractory period
the heart is partially depolarized and a new action potential will be inhibited but not impossible
The parasympathetic nervous system
- Sends messages mainly through vagus nerve- Atropine blocks actions of PNS and vagus nerve causing HR to increase
The sympathetic nervous system
- Release norepinephrine ttavels to SA node, AV node and ventricles- every beta agents effects the heart by increases hearts rate, force and automaticity - Vasoconstriction is cause by alpha agent- Vasodilation is caused by beta agent
- Alpha 1 receptors
are primarily located on peripheral blood vessels and stimulation results in:o Peripheral vasoconstrictiono Mild bronchoconstrictiono Increased metabolismo Stimulation of sweat glands
- Alpha 2 receptors
are primarily located on nerve endings and stimulation results in:o Control release of neurotransmitters
- Beta 1 receptors
are primarily located within the cardiovascular system and stimulation results in:o Increased heart rate (positive chronotropic)o Increased strength of cardiac contraction (positive inotropic)o Increased cardiac conduction (positive dromotropic)
- Beta 2 receptors
are primarily located on bronchial smooth muscle and stimulation results in:o Bronchodilationo Peripheral vasodilation
Causes of dysrhythmias
- Acid base disturbance- ANS imbalance- CNS damage- Certain poisons- Drugs- Endocrine disorders- Hypothermia- Hypoxemia- Ischemia o infarction- trauma
- disrhythmias happen after an AMI for 2 reasons
- irritability of the ischemic heart muscle surrounding the infarct may cause the damage muscle to generate abnormal cardiac contractions 2. because the infarct damages the conduction
Sodium (Na+)
goes into cell and initiates depolarization
Potassium (K+):
flows out of the cell to initiate repolarization
HypokalemiaHyperkalemia
Hypokalemia: increased myocardial irritabilityHyperkalemia: decreased automaticity/conduction
Calcium (Ca)
has major role in the depolarization of pacemaker cells (maintain depolarization) and in myocardial contractility
Hypocalcemia Hypercalcemia
Hypocalcemia: decreased contractility and increased myocardial irritability Hypercalcemia: increased contractility
Magnesium (Mg)
stabilizes the cell membrane: acts in concert with potassium and opposes the actions of calcium
Hypomagnesemia Hypermagnesemia
Hypomagnesemia: decreased conductionHypermagnesemia: increased myocardial irritability
Absolute Refractory Period
the cardiac muscle cell is completely insensitive to further stimulation Start of the QRS and ends at middle of T wave
Relative Refractory Period
During the relative refractory period, the muscle cell is more difficult than normal to excite, but it can still be stimulated.
Nervous system controlling heart rate
Two nerves link the cardiovascular center in the medulla oblongata of brain with the SA node of the heart1. Accelerator nerve (sympathetic NS)2. Vagus nerve (parasympathetic NS):
Accelerator nerve (sympathetic NS)
when stimulated, releases neurotransmitter at the SA node to increase heart rate
Vagus nerve (parasympathetic NS)
when stimulated, releases neurotransmitter at the SA node to decrease heart rate
Electrical Conduction System
• Automaticity• Generates its own electrical impulses without stimulation from nerves • Unique feature of the heart• Specialized conduction tissue• Pacemaker
The Sinoatrial (SA)Node
• The Primary Pacemaker - Theoretically, any cell can act as a pacemaker. - Located in the right atrium, near the inlet of the superior vena cava - Receives blood from the Right Coronary Artery in 50-60% of population - Fastest pacemaker in the heart - Inherent rate of 60 to 100 beats per minute(bpm)
Secondary Pacemakers
If the SA becomes damaged or is suppressed - AV node inherent rate 40-60 bpm (RCA blood flow in 85-90% of population). - Purkinje fibers 20-40 bpm
ECGs
- The ECG is a graphic representation of the heart’s electrical activity. - It does not provide information regarding mechanical events.- Valuable diagnostic tool for identifying cardiac abnormalities. - For good blood flow the electrical signal must send and the heart must respond
Indications for ECG Monitoring
- Patients at risk for dysrhythmias shall receive continuous ECG monitoring - Known or suspected cardiac patients - Suspected Overdose- Electrical Injuries- Syncope - Elderly patients “feeling unwell”- Issues concerning the Sympathetic System
Voltage Positive:Negative:
positive- Seen as an upward deflection on the ECG tracing.negative- Seen as a downward deflection on the ECG tracing. - Flowing backwardsisoelectric- No electrical current detected.- Seen as a straight baseline on the ECG.
ECG Leads - Bipolar lead*:- Unipolar lead:
- Bipolar lead*:o Two electrodes of opposite polarity. - Unipolar lead: o Single positive electrode and reference point.
Lead Placement
- White (upper right), black (upper left), green (lower right), red (lower left)- Between ribs, does not conduct well on bone - Positive always at the bottom
lead triangle
GO LOOK AT IT - double positive is on the bottom-top right (patients right) double negative-top left (patients left) negative and positive
ECG Graph Paper
- Each Little square is 1mm x 1mm 0.04sec- Each Large square is 5mm x 5mm 0.20 sec
Calibration
- The sensitivity of the 12-lead ECG machine is standardized - When properly calibrated, a 1-mV electrical signal produces a 10-mm deflection (two large squares) on the ECG tracing
Time Interval
- Denoted by short vertical lines on the ECG graph paper. - At standard speed, the distance between each short vertical line is 75 mm (3 seconds).
- Depolarization
The sinoatrial (SA) node on the wall of the right atrium initiates depolarization in the right and left atria, causing contraction, which corresponds to the P wave on an electrocardiogramo Discharge of the impulse
- Repolarization
resets charge
- P wave
depolarization of the atriumso Impulse being sent to AV nodeo Positive deflection because its going towards positive
- Q wave
polarization of right ventricle (may not have)o Bigger the Q wave the bigger the injuryo If you can fill it with water its important
- R wave
left ventricle contracting
-QRS
ventricular depolarization
- T
ventricular repolarizationo Reset
PRI IntervalQRS intervalR-R Interval
- PRI should me 0.12-0.20 sec how long it takes impulse to get from sa node to av node- QRS less than 0.12 sec - R to R interval: top of R wave to next