When preparing for an arterial blood gas analysis in a patient in cardiac arrest, why is femoral artery puncture indicated?

The indication for performing a femoral artery puncture during cardiac arrest primarily stems from its accessibility in an emergency situation. During cardiac arrest, standard sites for arterial puncture, such as the radial or brachial arteries, may not be palpable due to hypotension or poor circulation. The femoral artery, located in the groin, typically remains a more reliable access point since it is larger and deeper, making it less likely to collapse compared to more peripheral arteries.

While obtaining arterial blood for gas analysis is crucial for accurate assessment and management, the primary consideration in the context of cardiac arrest is the ability to access the artery reliably and efficiently. While obtaining arterial blood does provide a direct measure of the patient’s oxygenation and acid-base status, the emphasis on accessibility underlines why this site is chosen during critical scenarios. Thus, the femoral artery puncture is prioritized to quickly obtain necessary blood samples for accurate diagnosis and intervention, rather than solely focusing on the accuracy of arterial versus venous blood.