Final answer:
When collecting a blood smear, it is standard to use a prepared stained slide, scan systematically using a pattern and count up to 100 white blood cells, and if preparing a smear, to ensure it is dried and heat-fixed before staining.
Step-by-step explanation:
Standard practice when collecting a blood smear involves obtaining a prepared slide that has been stained, typically using Wright's stain, and then examining the slide under a microscope. During the initial scan, one evaluates the appearance of red blood cells and platelets. Following that, a more detailed analysis is performed to identify and count the different populations of white blood cells. Typically, one will count until reaching a total of 100 cells to get a representative sample of the white blood cell population.
When performing the analysis, it is common to use a systematic scanning pattern. Although a grid is often recommended for systematic scanning, if a grid is not available, a simple table can be constructed to make a mark for each leukocyte type identified. One aims to classify at least 50, and up to 100 cells, to determine if the percentages of cells represent a normal blood smear or indicate an abnormal condition.
Another standard practice when preparing a smear, such as from an oral mucosa sample, is to make sure that it is heat fixed after drying. This involves passing the slide through the flame of a Bunsen burner. This step helps to adhere the cells to the slide and kill bacteria so that staining can be performed effectively.