ECG and CPR Overview

Study Notes

Electrocardiogram (ECG)

The ECG represents the sum of multiple action potentials (AP) occurring simultaneously in numerous myocardial cells.
It records the overall spread of electrical activity throughout the heart.
ECG signals are extracellular recordings.
The amplitude of ECG electrical signals is significantly smaller than the AP signal by the time it reaches the body's surface.
Bipolar ECGs measure the difference between signals.
ECG records electrical activity during both depolarization and repolarization events.
Different phases of the ECG waveform correlate with specific cardiac events.
An ECG at 0 reveals the state of the heart because it captures the same state at two points, indicating no difference.

Cardiopulmonary Resuscitation (CPR)

CPR is indicated for pulseless ventricular tachycardia and ventricular fibrillation.
Prognosis is favorable if CPR is initiated within 6 minutes of cardiac arrest.
Brain cells deprived of oxygen for 4-6 minutes may not survive after oxygen is reintroduced after 6 minutes.
CPR alone results in few complete recoveries, and survivors may experience complications.
Only 5-10% of people who receive CPR survive.
CPR preserves the body for defibrillation and advanced life support.

Automated External Defibrillators (AEDs)

AEDs are indicated for ventricular fibrillation and pulseless ventricular tachycardia.
They are used to shock hearts that are active but have irregular and life-threatening rhythms.
AEDs automatically diagnose arrhythmia, determine the required shock level, and deliver the shock.

Description

This quiz explores the fundamentals of Electrocardiograms (ECGs) and Cardiopulmonary Resuscitation (CPR). Learn about how ECG signals reflect heart activity and the critical role of CPR in cardiac emergencies. Test your knowledge on the correlation between ECG waveforms and cardiac events as well as the importance of timely CPR.