What should be assessed immediately upon defibrillator availability after CPR initiation?

Upon the availability of a defibrillator following the initiation of cardiopulmonary resuscitation (CPR), the critical step is to assess the patient's cardiac rhythm and determine whether it is shockable. This is essential because the success of defibrillation primarily depends on the presence of specific arrhythmias that can be corrected by delivering an electric shock, such as ventricular fibrillation or pulseless ventricular tachycardia.

The process is part of the algorithm for managing cardiac arrest, where timely defibrillation can significantly improve survival rates. The sooner the shock can be delivered if indicated, the better the chances of restoring a viable cardiac rhythm and improving perfusion to vital organs.

Other assessments, such as checking the patient's blood type, recent medical history, or the effectiveness of CPR, are important but not immediate priorities at the moment defibrillation capability is realized. These can be addressed subsequently after the initial rhythm assessment.