What does the letter "H" represent in the Hs and Ts of ACLS reversible causes?

In the context of ACLS, the letter "H" represents "Hypoxia." Recognizing hypoxia as one of the reversible causes of cardiac arrest is crucial because it addresses a potential underlying issue: insufficient oxygenation of the patient’s tissues. Hypoxia can lead to organ failure and cardiac dysfunction, so ensuring that oxygen levels are adequate is a priority during resuscitation efforts.

By identifying and addressing hypoxia promptly—such as administering supplemental oxygen or ensuring proper ventilation—healthcare providers can significantly improve the likelihood of restoring a normal cardiac rhythm and supporting the return of spontaneous circulation. This emphasizes the importance of maintaining adequate oxygenation, particularly in emergency scenarios.

While hypotension, hyperkalemia, and hemorrhage are relevant medical concerns, they are represented by different letters in the Hs and Ts mnemonic used in ACLS. Understanding each element in this mnemonic provides a structured approach to diagnosing and treating the causes of cardiac arrest efficiently.