How is atrial fibrillation characterized in terms of rhythm and P waves?

Atrial fibrillation is characterized by an irregularly irregular rhythm and the absence of discernible P waves on the electrocardiogram (ECG). The term "irregularly irregular" refers to the chaotic electrical activity in the atria, leading to an inconsistent heart rate and rhythm that lacks any predictable pattern. This results in varying R-R intervals on the ECG.

In the case of atrial fibrillation, you will not see distinct P waves, which are indicative of normal atrial depolarization. Instead, the ECG may show a wavy baseline, known as fibrillatory waves, reflecting the disorganized electrical impulses originating from multiple areas within the atria.

Recognizing these characteristics is crucial for proper diagnosis and management in advanced life support contexts, as they inform clinicians about the underlying cardiac activity and guide treatment decisions.