Pulseless electrical activity (PEA)

Definition

An organized electrical rhythm on the ECG with no palpable pulse, because the ventricles either do not contract or contract too weakly to produce a detectable pulse (cardiac ultrasound may still show some cardiac motion); it is one of the four cardiac-arrest rhythms. PEA covers a heterogeneous group of organized rhythms, so it is recognized by the absent pulse, not by the ECG pattern. Its potentially reversible causes are often grouped as the H's and T's (hypovolemia, hypoxia, hydrogen ion/acidosis, hypo-/hyperkalemia, hypothermia; tension pneumothorax, tamponade, toxins, pulmonary thrombosis, coronary thrombosis).

Clinical noteThe diagnosis rests on the absent pulse, not the ECG morphology: the identical tracing in a patient with a pulse is simply that rhythm, not PEA.