Exam 1 Basic EKG Flashcards
The heart has the innate ability to generate its own spontaneous action potentials without any external stimuli, a phenomenon known as __________.
Automaticity
What are the two types of cells in the heart?
Pacemaker Cells (spontaneous action potentials)
Contractile Cells
When there is a stimulation above the threshold, __________ channels cause cell-to-cell conduction resulting in depolarization.
This will release ________ to interior myocytes and causes contraction.
_______ outflow causes repolarization.
Sodium Channels
Calcium
Potassium
Once the action potential is generated by the SA node, conduction will go to the right atrium via the __________ pathway.
Conduction will also travel from the right atrium to the left atrium via ____________.
Internodal Pathway
Bachman’s Bundle
The inherent pace of the SA node.
The inherent pace of AV node.
60-100 bpm
40-60 bpm
Atrial fibrillation will result in a _______% decrease in cardiac output.
20-25% decrease in CO
The bundle of His is located in the __________.
The bundle of His has pacemaker cells that can generate an action potential at _________ beats/minute.
interventricular septum
40 to 60 bpm
The bundle branch consists of pacemakers cells that can generate _________ bpm.
20 to 40 bpm
How many mV are the large boxes?
How many mV are the small boxes?
How many seconds are the small boxes?
How many seconds are the larges boxes?
0.5 mV
0.1 mV
0.04 seconds
0.20 seconds
What does the P-wave represent?
What is the normal duration of P-waves?
Atrial Depolarization
less than 0.12 seconds
What does the PR interval represent?
What is a normal PR interval?
What is a PR interval greater than 0.20 seconds called?
PR interval represents the time from the onset of atrial depolarization (contraction) to the onset of ventricular depolarization. The pause for the blood to go from the atria to the ventricles.
0.12 to 0.20 seconds
First-degree AV block
What does the QRS complex represent?
What is the duration of the QRS complex?
Ventricular depolarization
<0.12 seconds
What does the ST segment represent?
ST segment represents the interval between depolarization and repolarization of the ventricles.
Early stages of ventricular repolarization.
Elevation > 1mm is significant (injury/ischemia)
What does the T wave represent?
Repolarization of the ventricle
What rhythms will have retrograde p-waves?
Junction rhythms
(Rhythm is coming from the AV node and back up to SA node)
Why is the latter PR interval flat?
No contraction, so the blood can continue to flow down the ventricles.
What do we associate with a QRS complex wider than 0.12 seconds?
Bundle branch block
What causes elevated T-waves?
Hyperkalemia
When is atrial repolarization?
During QRS complex
What is the rhythm?
Sinus Rhythm
What is the rhythm?
Sinus Bradycardia
What is the rhythm?
Sinus Tachycardia
(100-150 bpm)
What is the rhythm?
Junctional Rhythm
HR 40-60 bpm
Signal starts in AV node
(look for the inverted p-wave)
What is the rhythm?
Junctional tachycardia
HR >60 bpm
Signal starts in AV node
What is the rhythm?
PSVT
(HR>150)
What does paroxysmal mean?
“comes and goes”
What is the rhythm?
Premature atrial contraction
(find the underlying rhythm and then figure out the accessory rhythm and look for compensatory pause)
What is the rhythm?
A-fib
(Think irregularly irregular)
What is the rhythm?
A-flutter
(Sawtooth pattern)
What is the rhythm?
Premature ventricular contraction
What is the rhythm?
1st-degree AV Block
What is the rhythm?
Bigeminy PVC
(PVC after every other normal beat)
What is the rhythm?
Trigeminy PVC
(PCV on the 3rd beat)
What is the rhythm?
2nd degree Type 1 AV Block or Wenckebach
What is the rhythm?
2nd degree Type 2 AV Block
What is the rhythm?
Complete heart block or 3rd degree AVB
What is the rhythm?
Vtach
(150-180 bpm)
What is the rhythm?
Vfib
Polymorphic vtach is also known as _________-
Torsades de Pointes
How do you treat V-fib?
Defibrillation (electricity)
How do you treat polymorphic vtach?
Mag and Electricity
What general anesthetics will cause sensitive myocardium?
Halothane and enflurane
How does cocaine and ketamine cause tachycardia?
Norepinephrine reuptake inhibitors
What anesthetic gas can cause bradycardia in infants?
Too much Sevoflurane
What anesthetic gas can cause prolonged QT during induction?
Desflurane
Smashing the face mask will cause pressure to build up in the eye and will result in bradycardia due to what reflex?
Oculocardiac Reflex
Five and Dime Reflex
A local anesthetic will cause a _____________ block.
Which will result in ___________.
Sympathetic
Severe Bradycardia
What happens if you inject local anesthetic into the blood vessel?
What is the treatment?
Patient will become asystolic (and so will you)
Treat with lipid rescue
Endotracheal intubation can put pressure on the _________, resulting in bradycardia and other hemodynamic disturbances.
vagus nerve.
There can be autonomic reflexes during a surgical case stimulation of the carotid baroreceptors can cause_________.
Bradycardia
Prevent this by asking the surgeon to put more local anesthetic around the area or slap their hand
During a laparoscopic case, insufflation can cause ____________ due to _________________.
Bradycardia due to loss of venous return.
Tugging the ___________ or _________ will cause bradycardia.
Peritoneum; Cervix
Hysterectomy
What cannulation procedure can cause dysrhythmias?
Central lines
What is the rhythm?
Sinus Rhythm with Trigeminy
What is the rhythm?
PSVT
What is going on here?
Ventricular Paced
What is the rhythm?
2nd degree AV Block Type II
What is the rhythm?
Artifact
What is the rhythm?
PAC
What is the rhythm?
A-fib
Rhythm is irregularly irregular
What is the rhythm?
Atrial Paced
What is the rhythm?
Atrial Flutter
What is the rhythm?
A-fib
Rhythm is irregularly irregular
What is the rhythm?
Sinus Brady
What is the rhythm?
Sinus Rhythm with PJC
See the retrograde p-wave?
What is the rhythm?
V-fib
What is the rhythm?
A-fib
What is the rhythm?
SVT
What is the rhythm?
Junctional Tachy
Sometimes there might not be the classic retrograde p-wave
What is the rhythm?
Idioventricular Rhythm or IVR
What is the rhythm?
AV Sequential Pacer
What is the rhythm?
Idioventricular Rhythm or IVR
What is the rhythm?
Artifact
Look at both leads, they do not correlate.
What is the rhythm?
A-fib with Bigeminy
What is the rhythm?
Sinus with Junctional Escape
Look at the fourth beat, no p-wave
What is the rhythm?
Torsades de Pointes
Treat with mag and electricity
What is the rhythm?
Junctional Rhythm
What is the rhythm?
Sinus Rhythm with Hyperkalemia
What is the rhythm?
A-fib
What is the rhythm?
2nd degree Type 2 AVB
What is the rhythm?
NSR with PVC
What is the rhythm?
Sinus Arrest
Can be caused by adenosine or the patient being hypoxic