Urine Specific Gravity Refractometer

Summary

Dr. Ben Matthews demonstrates how to measure urine specific gravity using a refractometer in the exercise science lab at Montclair State University. The process involves placing two to three drops of urine on the refractometer, closing the lid, and examining the scale under a bright light. By reading the black line on the specific gravity scale, users can determine hydration levels. The video emphasizes proper cleaning of the refractometer and its surroundings, as well as the importance of urine specific gravity in assessing hydration. Dehydrated samples show higher specific gravity and sodium levels, while well-hydrated samples exhibit lower readings.

Takeaways

• 😀 A refractometer is used to measure urine specific gravity, which helps assess hydration status.
• 😀 To use the refractometer, apply 2-3 drops of urine onto the glass surface using a transfer pipette.
• 😀 Close the lid of the refractometer after adding the urine, and the liquid will spread across the glass.
• 😀 The refractometer should be viewed under bright overhead light to ensure accurate readings.
• 😀 The specific gravity scale is located on the lower left side of the refractometer.
• 😀 Read the value where the black line crosses the specific gravity scale to determine the result.
• 😀 If the black line is unclear, clean the refractometer and repeat the process.
• 😀 After use, clean the refractometer with a tissue and disinfect it with an alcohol swab.
• 😀 Allow the alcohol to fully evaporate before storing the refractometer.
• 😀 Urine specific gravity above 1.020 typically indicates dehydration.
• 😀 Sodium levels in urine are linked to specific gravity, with higher sodium levels corresponding to higher specific gravity in dehydrated samples.

Q & A

What is the purpose of using a refractometer in this demonstration?

The refractometer is used to measure the urine specific gravity, which helps assess hydration status.

How many drops of urine should be used for the refractometer measurement?

You should use 2-3 drops of urine.

Where should the urine be placed on the refractometer?

The urine should be placed on the small circular glass surface under the top cover of the refractometer.

Why is it important to perform the measurement under a bright overhead light?

The bright overhead light helps the refractometer light shine through the urine, making it easier to read the specific gravity.

What should you do if the black line on the refractometer scale is not distinct?

If the black line isn't distinct, clean the refractometer and start over, as this could be caused by air bubbles or improper coverage of the glass.

How do you read the specific gravity on the refractometer?

Look at the lower left scale of the refractometer where the black line crosses, and read off the specific gravity value.

What does a specific gravity value above 1.020 indicate?

A specific gravity value above 1.020 indicates dehydration.

What is the relationship between sodium levels and urine specific gravity?

Higher sodium levels are typically associated with higher urine specific gravity, which can indicate dehydration.

How should you clean the refractometer after use?

After use, clean the refractometer by wiping off the urine with a tissue and then disinfecting it with an alcohol swab. Allow the alcohol to evaporate before storing the device.

Why is it important to clean the countertop where the measurement was done?

It’s important to clean the countertop to remove any urine spills and maintain a hygienic workspace.