Final answer:
The ECG waveform showing no pulse is interpreted as Ventricular fibrillation (B) by the resuscitation team, which is a medical emergency requiring immediate defibrillation to reestablish a normal heart rhythm.
Step-by-step explanation:
The resuscitation team interprets the ECG waveform with no pulse as Ventricular fibrillation (B).
Ventricular fibrillation is characterized by disorganized, ineffective twitching of the ventricles, resulting in no blood flow and a state of cardiac arrest. In the ECG, ventricular fibrillation appears as a series of irregular waveforms of varying shapes and amplitudes (Figure 19.25d). This condition is a medical emergency requiring immediate treatment, typically in the form of defibrillation. Defibrillation attempts to stop the uncoordinated contractions by depolarizing a critical mass of the heart's muscle cells.
When successful, this resets the heart's rhythm, allowing the sinoatrial (SA) node to reestablish a normal conduction cycle. An ECG is essential for diagnosing ventricular fibrillation, as it provides a visual representation of the heart's electrical activity, and a pulseless state in a patient with this ECG pattern typically confirms the diagnosis. As described, atrial fibrillation also has a disorganized electrical activity pattern, but it does not result in a pulseless state. Torsades de pointes and monomorphic pulseless ventricular tachycardia have distinct ECG presentations that differ from ventricular fibrillation.