Blood Lab - Hematocrit

Key Concepts

  • Hematocrit (HCT) is the percentage of erythrocytes, or red blood cells (RBCs), in a whole blood sample.

  • Hematocrit (HCT) is determined by separating the formed elements from the plasma and measuring the packed red blood cell volume.

  • Normal hematocrit varies depending on many factors, but generally accepted ranges are:

    • Adult males: 42–52%

    • Adult females: 37–47%

  • An abnormally elevated hematocrit can occur for several reasons, such as being at a high altitude, having an elevated testosterone level, with certain diseases, and if the person is "blood doping."

  • Blood doping refers to any of several methods used to increase the blood oxygen-carrying capacity.


Overview

  • In this simulation, you will measure the hematocrit of three blood samples from athletes.

  • Your task is to determine if any of the athletes are blood doping.

  • You have blood samples of known values to compare. Positive control represents a doped sample. Negative control represents a sample that is not doped.

  • Take a moment to reflect on personal safety precautions. Working with blood is a potentially hazardous situation. In real life, you should:

    • Wash the laboratory lab benches before and after the procedures with an appropriate disinfectant.

    • Wear disposable gloves and goggles when handling blood samples.

    • Wash your hands after the laboratory.

    • Only use a blood lancet once.

    • Dispose of used lancets, pipettes, and other blood contaminated items in the appropriate hazardous waste container, never a regular trash container


Before you begin

  • Loading the Centrifuge
    Centrifuge must be balanced to run properly. Remember to make sure each capillary tube has another directly across from it in the centrifuge

  • How to Measure
    Measurement of the hematocrit is made simple by aligning the capillary tube to the hematocrit chart. To do this, move the capillary tube left or right along the chart such that the blood and clay are even with the bottom of the chart, and the top of the plasma is even with the top of the chart. Once you have aligned the capillary tube, click and you will see the measurement.


Laboratory Simulation

Steps

  • Phase 1: Identify lab equipment

    • Identify equipment in lab

  • Phase 2: Positive control sample

    • Pick up capillary tube and touch tube to positive sample to fill tube with blood

    • Use alcohol wipe to clean tube

    • Click clay to seal tube at one end

    • Place tube in centrifuge at position 4

  • Phase 3: Negative control sample

    • Pick up capillary tube and touch tube to negative sample to fill tube with blood

    • Use alcohol wipe to clean tube

    • Click clay to seal tube at one end

    • Place tube in centrifuge

  • Phase 4: Sample A

    • Pick up capillary tube and touch tube to sample A to fill tube with blood

    • Use alcohol wipe to clean tube

    • Click clay to seal tube at one end

    • Place tube in centrifuge at position 8

  • Phase 5: Sample B

    • Pick up capillary tube and touch tube to sample B to fill tube with blood

    • Use alcohol wipe to clean tube

    • Click clay to seal tube at one end

    • Place tube in centrifuge at position 20

  • Phase 6: Sample C

    • Pick up capillary tube and touch tube to sample C to fill tube with blood

    • Use alcohol wipe to clean tube

    • Click clay to seal tube at one end

    • Place tube in centrifuge at position 12

  • Phase 7: Balance and run the centrifuge

    • Pick up capillary tube and click clay to seal tube at one end

    • Place tube in centrifuge

    • Turn on centrifuge and run for 4 minutes

    • Turn off centrifuge

    • Measure each tube with blood by aligning it on the hematocrit chart and then click to display the measurement. Record in Lab Data

    • Dispose of each capillary tube in sharps container after measurements are recorded

    • Dispose of capillary tube used to balance centrifuge in sharps container

  • Phase 8: Lab wrap-up

    • Select your answer to the question

  • Phase 9: Apply what you have learned

    • Select your answer to the question

  • Phase 10: Save Lab Data

    • Relevant Lab Data is available to be saved for personal reference. Data will be available if you return to this laboratory simulation


Supplies

Collected Lab Data