Which laboratory test is important to check for a patient in shock?

In the context of a patient in shock, checking lactate levels is particularly important as it helps gauge the severity of tissue hypoperfusion and anaerobic metabolism, which are critical in identifying the state of shock. Elevated lactate levels can indicate that the body's tissues are not receiving enough oxygen, which is often a consequence of shock.

While the complete blood count can provide insights into the patient's overall health and identify issues like anemia or infection, and blood glucose levels are essential to rule out diabetes or stress responses, neither is as directly indicative of the physiological state associated with shock as lactate levels.

The inclusion of all three tests enhances the clinician's ability to paint a comprehensive picture of a patient's condition. Therefore, the correct choice recognizes the importance of a holistic assessment, which is necessary in emergency situations to ensure proper diagnosis and treatment of shock.