Microhematocrit Quiz

Capillary action is the process by which a liquid, such as blood, is drawn into a narrow tube, such as a capillary tube. This occurs due to the adhesive and cohesive properties of the liquid, which allow it to climb up the walls of the tube against the force of gravity. In the case of blood, it is drawn into capillary tubes through capillary action, facilitating various medical procedures such as blood sampling and testing. Therefore, the statement "blood is drawn into the capillary tubes by capillary action" is true.

The statement is false because even though capillary tubes are small, they still need to be balanced in the microhematocrit centrifuge. Balancing the tubes ensures that the centrifugal force is evenly distributed, preventing any imbalances or errors in the separation of blood components. Failure to balance the tubes could result in inaccurate hematocrit readings and potentially affect patient diagnosis or treatment.

A spun hematocrit is a test that separates the different components of blood, including red blood cells, white blood cells, and platelets. The buffy coat layer is the layer between the red blood cells and the plasma that contains white blood cells and platelets. A very prominent buffy coat layer indicates an increased number of white blood cells, which is known as leukocytosis. Leukocytosis can be caused by various factors, including infection or leukemia. Therefore, a very prominent buffy coat layer in a spun hematocrit suggests leukocytosis due to infection or leukemia.

Dark plasma or plasma that is very yellow indicates a high bilirubin level. Bilirubin is a yellow pigment that is produced when red blood cells break down. It is normally processed by the liver and excreted in the bile. However, if there is a problem with liver function or an excessive breakdown of red blood cells, bilirubin levels can become elevated. This can lead to a condition called jaundice, which is characterized by yellowing of the skin and eyes. Therefore, a spun hematocrit with dark or very yellow plasma suggests a high bilirubin level.

To obtain capillary blood, it is necessary to invert the blood sample 60 times or place it on a mechanical mixer for at least 2 minutes. This process ensures proper mixing of the blood components and prevents any potential clumping or settling of cells. By doing so, the capillary blood obtained will be representative of the overall blood composition and provide accurate test results.

The two hematocrit duplicate results that can be used are 32% and 34%. These results are close to each other, indicating a high level of agreement between the duplicates. A small difference between the duplicate results suggests that they are reliable and accurate.

The normal range for hemoglobin in adult males is generally between 13.5 to 17.5 grams per deciliter (g/dL). A hematocrit reading of 27% indicates that 27% of the blood volume is made up of red blood cells. Since hemoglobin is the protein found in red blood cells that carries oxygen, it is directly related to the hematocrit value. Therefore, a hematocrit reading of 27% suggests that the hemoglobin value should be around 9g/dL, which falls within the normal range.

In a spun hematocrit, very cloudy plasma indicates a high fat level. This is because fats are insoluble in water and can cause the plasma to appear cloudy when present in high concentrations.

Living at higher altitudes, severe dehydration, anemia, polycythemia, leukemia, and bleeding can all have an impact on hematocrit values. However, only anemia, leukemia, and bleeding would lead to a decrease in hematocrit values. Anemia is characterized by a decrease in the number of red blood cells, which would result in a lower hematocrit value. Leukemia, a type of cancer that affects the blood and bone marrow, can also cause a decrease in hematocrit values. Bleeding, whether due to injury or a medical condition, can lead to a loss of blood and subsequently lower hematocrit values.

Duplicate hematocrit results cannot be used when there is a significant difference between the two measurements. In this case, the difference between 32% and 35% is considered significant, indicating a potential error or inconsistency in the measurements. Therefore, these duplicate results should not be used.

Hematocrit is the percentage of red blood cells in the total blood volume. Hemoglobin is a protein in red blood cells that carries oxygen. There is a direct correlation between hemoglobin and hematocrit levels. On average, the hematocrit is about three times the hemoglobin level. Therefore, if Annie's hemoglobin is 18 g/dL, her hematocrit should be around 54%.

Living at higher altitudes can lead to an increase in hematocrit values because the body responds to the lower oxygen levels by producing more red blood cells, which increases the hematocrit. Severe dehydration can also cause an increase in hematocrit because it leads to a decrease in plasma volume, causing the concentration of red blood cells to increase. Polycythemia, a condition characterized by an excessive production of red blood cells, can also result in higher hematocrit values.

The correct answer includes a list of quality assessment procedures that must be followed in order to ensure accurate and reliable results in the laboratory. These procedures include calibrating the centrifuge, filling microhematocrit tubes at least three quarter full, running each patient sample in duplicates, ensuring that the duplicate samples agree within + or - 2%, repeating the test if results do not agree within + or - 2%, running hematology controls daily and charting the results, adequately mixing venous blood specimens before obtaining the two capillary tubes, following the standard operating procedure (SOP) manual when choosing appropriate time and speed, collecting capillary blood in a heparinized tube to prevent clotting, and avoiding air bubbles in the capillary tubes. These procedures are essential for maintaining accuracy and quality in laboratory testing.

The correct answer includes various safety procedures that must be followed when performing a microhematocrit test. These procedures include using plastic capillary tubes, Mylar wrapped capillary tubes, and self-sealing tubes. Additionally, the centrifuge interior should be cleaned frequently to prevent the build-up of aerosol. It is also important to lock the inner and external lid in place before operating the instrument and wait for the rotor to come to a complete stop before opening the centrifuge.