Question

If an average-weight adult male patient with a 7 gram/dL hemoglobin is given two units of packed cells, what would be the approximate new hemoglobin value (assuming there is no active bleeding or other predisposing factors that would shorten the survival of the blood cells

Answer 1

To estimate the new hemoglobin value after the patient is given two units of packed cells, calculate the total amount of hemoglobin in the packed cells and add it to the initial hemoglobin value.

Step-by-step explanation:

The approximate new hemoglobin value can be estimated by calculating the total amount of hemoglobin in the packed cells and adding it to the initial hemoglobin value. Each unit of packed cells typically contains around 200-250 mL of blood, and an average adult male has 5-6 liters of blood. Therefore, two units of packed cells would provide an additional 400-500 mL of blood.

Since the hemoglobin content of normal blood varies, an estimate of the average hemoglobin concentration in the packed cells is used. Based on the information provided, the average hemoglobin concentration is around 45%, which means that 45% of the total packed cell volume is made up of hemoglobin. Therefore, the approximate new hemoglobin value would be:

New Hemoglobin Value = Initial Hemoglobin Value + (Total Volume of Packed Cells x Hemoglobin Concentration)

Substituting the given values, the approximate new hemoglobin value can be calculated.