If a patient has remained supine for 8 hours, which analyte would be affected?

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Multiple Choice

If a patient has remained supine for 8 hours, which analyte would be affected?

The main idea here is how prolonged inactivity affects muscle-related markers. Creatine kinase (CK) is an enzyme concentrated in skeletal muscle and is released into the bloodstream when muscle tissue is damaged or under high mechanical stress from activity. When a person remains lying down for many hours, the muscles aren’t contracting, so there’s far less microtrauma and less leakage of CK into the blood. As a result, circulating CK levels tend to be lower than they would be with normal activity. Lactic acid, on the other hand, is tied to anaerobic metabolism. It rises when tissues experience low oxygen availability or intense exercise. Simply staying supine for 8 hours doesn’t reliably cause a sustained rise in lactate in a healthy person, so it’s less likely to be affected in this scenario. Cortisol could fluctuate due to stress, but the situation described is about a short-term, position-related change in muscle activity, not a systemic stress response. So, the analyte most affected by eight hours of lying supine is the creatine kinase level, which would be decreased due to reduced muscle activity and injury signaling.

The main idea here is how prolonged inactivity affects muscle-related markers. Creatine kinase (CK) is an enzyme concentrated in skeletal muscle and is released into the bloodstream when muscle tissue is damaged or under high mechanical stress from activity. When a person remains lying down for many hours, the muscles aren’t contracting, so there’s far less microtrauma and less leakage of CK into the blood. As a result, circulating CK levels tend to be lower than they would be with normal activity.

Lactic acid, on the other hand, is tied to anaerobic metabolism. It rises when tissues experience low oxygen availability or intense exercise. Simply staying supine for 8 hours doesn’t reliably cause a sustained rise in lactate in a healthy person, so it’s less likely to be affected in this scenario. Cortisol could fluctuate due to stress, but the situation described is about a short-term, position-related change in muscle activity, not a systemic stress response.

So, the analyte most affected by eight hours of lying supine is the creatine kinase level, which would be decreased due to reduced muscle activity and injury signaling.

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