ACLS RHYTHM IDENTIFICATION

1. Check the Heart Rate: A normal sinus rhythm typically has a rate between 60-100 beats per minute (bpm). If the rate is outside this range, it could be sinus bradycardia (slow) or sinus tachycardia (fast).

2. Look for P Waves: P waves represent atrial depolarization (the electrical activity before the atria contract). In a sinus rhythm, P waves should be present before every QRS complex. The P waves should have a consistent shape and be positive (upright) in lead II.

3. Regular Rhythm: Check that the rhythm is regular, meaning the distance between R-R intervals (the peaks of the QRS complexes) is consistent. Irregular intervals suggest an arrhythmia.

4. P-QRS-T Relationship: Ensure there is a 1:1 ratio of P waves to QRS complexes, meaning each P wave is followed by a QRS complex. This shows that the electrical signal is traveling properly from the atria to the ventricles.

5. PR Interval: The PR interval (time from the beginning of the P wave to the start of the QRS complex) should be between 0.12-0.20 seconds. A prolonged PR interval could indicate a heart block.

6. QRS Complex: The QRS duration should be less than 0.12 seconds. A wider QRS complex might indicate a ventricular problem or conduction delay.

1. Irregular, Chaotic Rhythm: The ECG will show irregular, erratic, and disorganized electrical waves. No consistent pattern of P waves, QRS complexes, or T waves. The baseline looks chaotic, with varying amplitude and frequency.

2. No P Waves: In ventricular fibrillation, there are no P waves present, which means the atria are not properly contracting. The electrical activity is random and originates in the ventricles.

3. No QRS Complexes: There are no identifiable QRS complexes as the ventricles are not contracting in a coordinated manner. Usual QRS complexes are replaced by rapid, irregular waves.

4. Irregular Waveform: The ECG will show rapid, fibrillatory waves of varying size (amplitude) and shape. This can range from small and fine to larger, coarser waves.

5. Heart Rate: The rate is usually rapid, but it's so chaotic that a consistent rate can't be measured.

1. Rapid Heart Rate: In ventricular tachycardia, the heart rate is typically very fast, often between 150-250 beats per minute (bpm).

2. Wide QRS Complexes: The QRS complexes are usually wide, lasting more than 0.12 seconds. This indicates that the ventricular depolarization is abnormal.

3. Regular or Slightly Irregular Rhythm: VTach often has a regular or slightly irregular rhythm, meaning the R-R intervals are consistent or slightly varying.

1. Flatline: Asystole presents as a flatline on the ECG. There are no discernible P waves, QRS complexes, or T waves.

2. No Heart Rate: There is no measurable heart rate or electrical activity in asystole. The heart is not beating.

1. Slow Heart Rate: Sinus bradycardia is characterized by a heart rate of less than 60 beats per minute (bpm).

2. P Waves: There should still be P waves before each QRS complex, indicating the signal is originating from the sinoatrial node.

1. Prolonged PR Interval: The key feature of 1st-degree AV block is a PR interval longer than 0.20 seconds. This indicates a delay in conduction between the atria and ventricles.

2. Regular Rhythm: Despite the prolonged PR interval, the rhythm should still be regular, with consistent R-R intervals.

3. P-QRS Relationship: There is a 1:1 relationship between P waves and QRS complexes, meaning every P wave is followed by a QRS complex.

1. Progressive PR Interval Lengthening: In Type 1 block, the PR interval progressively lengthens with each beat until a QRS complex is dropped (missing). This is known as the "Wenckebach" phenomenon.

2. Pattern: The pattern repeats itself, with the PR interval becoming progressively longer until a beat is dropped, followed by a return to a normal PR interval.

3. Regular P Waves: P waves are regular and occur at consistent intervals. The block is characterized by a regular pattern of dropped beats.

1. Fixed PR Interval: In Type 2 block, the PR interval remains constant before a QRS complex is dropped. There is no progressive lengthening as seen in Type 1.

2. Sudden Dropped Beats: QRS complexes are dropped suddenly without preceding changes in the PR interval. This often occurs in a regular pattern (e.g., every 2nd or 3rd beat).

3. Regular P Waves: P waves occur regularly, but some QRS complexes may be absent, leading to a variable ventricular rate.

1. Complete Heart Block: Third-degree AV block (complete heart block) shows no conduction between atria and ventricles. P waves and QRS complexes are not related.

2. P Waves and QRS Complexes: P waves and QRS complexes occur independently of each other. The atrial rate (P waves) and ventricular rate (QRS complexes) are different.

3. Regular Rhythm: The atrial and ventricular rhythms may be regular, but they are dissociated. The ventricular rhythm is typically slower and can be generated by a junctional or ventricular escape rhythm.

1. Rapid Heart Rate: SVT is characterized by a rapid heart rate, often between 150-250 beats per minute (bpm).

2. Narrow QRS Complexes: The QRS complexes are typically narrow (<0.12 seconds) if the rhythm is originating from above the ventricles.

3. Regular Rhythm: The rhythm is usually regular with consistent R-R intervals, but the heart rate is much faster than normal.

4. P Waves: P waves may be difficult to distinguish or may be buried within the T waves. In some cases, P waves may be present but are hidden due to the rapid rate.