What is the range of normal PCO2 levels in the blood?

The range of normal PCO2 (partial pressure of carbon dioxide) levels in the blood is indeed 37-43 mmHg. This value is important because it reflects the balance of carbon dioxide production and elimination in the body, indicating how well the respiratory system is functioning.

When the carbon dioxide level falls within this range, it generally signifies that the body is effectively regulating its acid-base balance and ensuring that the tissues are getting sufficient oxygen while efficiently removing CO2. Abnormal levels outside this range can indicate respiratory or metabolic issues; for instance, lower levels may suggest hyperventilation or decreased CO2 production, whereas higher levels may indicate hypoventilation or respiratory acidosis.

Understanding these normal ranges is crucial for evaluating a patient's respiratory function in clinical situations, and helps in diagnosing conditions related to respiratory dysfunction.