For ammonia and lactate testing, why is ice slurry used and how fast must samples be processed?

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Multiple Choice

For ammonia and lactate testing, why is ice slurry used and how fast must samples be processed?

In ammonia and lactate testing, the sample must reflect the patient’s true in vivo levels, but blood cells kept in the tube continue to metabolize after collection. Glycolysis inside the sample produces lactate, and other enzymatic activities can alter ammonia levels, so the numbers can drift if the sample isn’t cooled quickly. Using an ice slurry rapidly lowers the temperature, slowing these metabolic processes and helping preserve the original concentrations. Processing the sample within about 15 minutes of collection is crucial because even short delays allow measurable changes to occur, leading to falsely elevated lactate (and ammonia) values. Placing the sample on ice immediately further minimizes metabolic activity from the moment of collection, making the result more reliable. Options that describe keeping the sample warm, delaying processing for hours, treating ice as optional, or aiming to sterilize the sample don’t address the need to halt metabolism promptly, which is why they’re not appropriate.

In ammonia and lactate testing, the sample must reflect the patient’s true in vivo levels, but blood cells kept in the tube continue to metabolize after collection. Glycolysis inside the sample produces lactate, and other enzymatic activities can alter ammonia levels, so the numbers can drift if the sample isn’t cooled quickly. Using an ice slurry rapidly lowers the temperature, slowing these metabolic processes and helping preserve the original concentrations.

Processing the sample within about 15 minutes of collection is crucial because even short delays allow measurable changes to occur, leading to falsely elevated lactate (and ammonia) values. Placing the sample on ice immediately further minimizes metabolic activity from the moment of collection, making the result more reliable.

Options that describe keeping the sample warm, delaying processing for hours, treating ice as optional, or aiming to sterilize the sample don’t address the need to halt metabolism promptly, which is why they’re not appropriate.

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