Clinical features of CPA.

Apnoea
Absence of a palpable pulse, palpable apex beat or heart sounds
Absence of cranial nerve reflexes
Muscle hypotonicity
Mucous membranes often turn a dirty grey colour, but cyanosis or pallor may also occur depending upon the cause of the arrest
A central eye position and pupils become fixed and dilated (in 30-45 seconds)
Cornea becomes dry
Prior to an arrest the ECG may show ventricular ectopic complexes, ST segment and T wave changes
An arrest may be heralded by ventricular fibrillation, sinus bradycardia or asystole
The ECG will appear normal with EMD, hence the importance of not relying solely upon an ECG monitor
Agonal gasping - considered a poor prognostic indicator