EMT 230 Review Flashcards
Ability of cardiac pacemaker cells to generate their own electrical impulses spontaneously without external (or nervous) stimulation
Automaticity
Distribute the electrical impulse throughout the atria & transmitter the impulse from the SA node to the AV node
Internodal pathways, (Internodal tracts)
Middle arterial wall layer, comprised of smooth muscle, elastic, & collagen
Tunics media
Furosemide (Lasix) Class: ???
Loop diuretic
In the event of 1 or more coronary vessels become blocked an alternative route of blood flow is called
Anastomosis (collateral circulation)
What branch of the left coronary artery supply blood to the lateral wall of the left ventricle
Marginal
What do you do if your patient is bradycardic with a pulse & atropine is ineffective
Transcutaneous pacing
The best position for a patient with chest pain
Semi-fowlers
Sometimes seen after the T wave & represents Repolarization of the Purkinje fibers
U wave
During the initial phase of the Q-T interval, the heart is completely unable to respond to electrical stimuli
Absolute refractory period
From the peak of the T wave onward, the heart may be able to respond to premature stimuli
Relative refractory period
The more the myocardial fibers are stretched (up to a certain point) the more forceful the contraction will be
Sterling’s Law of the heart
The ion required for contraction of cardiac muscle
Calcium
The 1st positive deflection on the ECG which represents atrial Depolarization
P wave
Standard limb leads I,II,& III are also called
Bipolar leads
Septal MIs are viewed in leads
V1, V2
The sympathetic nervous system has 2 types of receptor fibers at the nerve endings
Alpha & beta receptors
The chemical neurotransmitter for the sympathetic nervous system
Norepinephrine
Lead I
Left arm (+), right arm (-)
Lead II
Left leg (+), right arm (-)
Lead III
Left leg (+), left arm (-)
Deep & symmetrically inverted T wave may indicate
Cardiac ischemia
ECG tracing is only a reflection of the
Electrical activity of the heart
An ECG does not provide information on mechanical events such as
Force of contraction, or blood pressure
What drug is likely lethal for ventricular escape rhythm
Lidocaine
Which branch of the left coronary artery extends around the posterior side of the heart
Circumflex branch
R-R method 2 for heart rate
Count large squares between two R peaks divide into 300
R-R method 3 for heart rate
Count small squares between two R waves & divide into 1500
Correctable causes of PEA
Cardiac tampons, tension pneumothorax, pulmonary embolism, MI, hypoglycemia, acidosis, hyper/hypokalemia, hypothermia, & overdoses
Less collectable causes of PEA
Massive MI damage from infarction, prolonged ischemia during resuscitation, profound hypovolemia, & massive pulmonary embolism
MI blood work indications
High Risk: elevated troponin I or T
Low Risk: elevated CK-MB