In cases of pulseless electrical activity (PEA), which of the following is one of the H's that can be a reversible cause?

In the context of pulseless electrical activity (PEA), one of the H's referring to potentially reversible causes is indeed hypoglycemia. This condition can lead to a lack of sufficient glucose supply to the brain and other vital organs, which may manifest as decreased cardiac output and a state of shock, potentially progressing to PEA.

The H's mnemonic includes hypovolemia, hypoxia, hydrogen ions (acidosis), hyperkalemia, hypokalemia, hypoglycemia, and hypothermia as causes that can lead to cardiac arrest in the setting of PEA, all of which are treatable. Hypoglycemia specifically highlights how metabolic derangements can contribute to cardiovascular collapse.

It is essential to recognize the need for prompt identification and management of these conditions in emergency settings, as correcting the underlying cause can restore cardiac function and is a critical part of advanced cardiac life support (ACLS) protocols.