What is the normal range for ionized calcium (iCa)?

The normal range for ionized calcium (iCa) is actually around 4.5 to 6.0 mg/dL. Ionized calcium is the biologically active form of calcium in the body and plays a critical role in various physiological processes, including muscle contraction, blood coagulation, and nerve function.

In this range, iCa reflects the level of calcium that is not bound to proteins and is readily available for the body's metabolic functions. Any values outside of this normal range can indicate underlying health issues, such as hypoparathyroidism in cases of low iCa or primary hyperparathyroidism in cases of elevated levels.

Understanding the normal range of iCa is crucial in critical care settings, as abnormal levels can lead to significant clinical consequences that require immediate intervention. Monitoring iCa levels can help guide treatment for patients with various conditions that impact calcium metabolism.