Experiment 6 - Smear Preparation PDF

HEMATOLOGY I LABORATORY MANUAL Name: Date: Section: Group: Score: EXPERIMENT 2 SMEAR PREPARATION Smear preparation is technique every medical technologist should master. Peripheral blood is the most appropriate specimen for this technique. Objectives: 1. Execute the proper way of preparing b...

HEMATOLOGY I LABORATORY MANUAL Name: Date: Section: Group: Score: EXPERIMENT 2 SMEAR PREPARATION Smear preparation is technique every medical technologist should master. Peripheral blood is the most appropriate specimen for this technique. Objectives: 1. Execute the proper way of preparing blood smears 2. Demonstrate the different methods of smear preparation 3. Identify the characteristics of a good smear MATERIALS: Anticoagulated blood Glass slides Pasteur pipette TWO-SLIDE OR WEDGE METHOD The Two-slide or Wedge method is the simplest and the most popular method of smear preparation. It employs one slide for the smear and another slide that serves as the spreader. PROCEDURE 1. Place a small drop of blood on the far end of a clean glass slide. 2. Position the spreader slide before the drop of blood at an angle of about 30°-45° and allow the blood to spread evenly on the vertex. 3. Move the spreader smoothly and rapidly over the length of the slide at a constant angle. Be sure to keep the spreader rm to the slide. 4. Air-dry. fi 1 HEMATOLOGY I LABORATORY MANUAL CRITERIA OF A GOOD SMEAR 1. 2. 3. 4. There should be an even transition from the thick area to the thin area. The smear must cover ⅔ or ¾ of the slide. It must have a smooth and an even surface, free from ridges, waves, or holes. It must have a feathery a edge. OTHER METHODS OF SMEAR PREPARATION A. Two-Cover Slip or Ehrlich's Two-Coverglass Method Procedure: 1. Get two cover glasses. Hold one coverglass on its adjacent corners with the thumb and index nger. 2. Place one small drop of blood on top of the held coverglass. 3. Position the other coverglass on top of the coverglass with blood so that the two form a 16-sided gure as illustrated below. As this is done, the blood begins to spread. 4. Before the blood completely spreads, separate the coverglasses by doing a rapid, even, horizontal, and lateral pull. Avoid squeezing the coverglasses together. 5. Air-dry the coverglass. B. Spinner's Method The spinner's method is done using an instrument such as the Hemaspinner. Procedure: 1. Position a clean glass on a platen. fi fi 2 HEMATOLOGY I 2. 3. 4. 5. LABORATORY MANUAL Place 3-4 drops of blood in the middle of the slide. Close the instrument. The platen spins at high speed. Excess blood is expelled into a catch basin. The resultant slide is completely covered with a thin monolayer of cells. a NOTE: Modern spinners contain an optical system that has a sensor that detects if the cells have separated properly. This prompts the platen to automatically stop spinning. C. Automated Smear Preparation Sysmex SP-1000i is an instrument used for automated slide-making and staining of blood (Fig. 2.4). Smears are prepared after the blood sample has been analyzed. The need for such preparation is determined by the instrument's computer based on the hematologic results. The amount of blood, the angle, and the speed of the spreader slide is dependent on the hematocrit value. A smear can be prepared every 30 seconds, and is labeled with the patient's name, number, and date. The Beckman Coulter blood analyzer is another instrument equipped with smear making and staining (Fig . 2.5).. 3 HEMATOLOGY I LABORATORY MANUAL Name: Section: Date: Group: Score: REVIEW QUESTIONS 1. What is the purpose of preparing a blood smear in the laboratory? 2. What is the ideal thickness of a blood smear, and how is it achieved? 3. What are the common errors Of artifacts that can occur during blood smear preparation, and how can they be minimized or corrected? 4. How does the choice of anticoagulant affect the quality of a blood smear, and why is this important to consider? 5. Describe the quality control measures that should be in place to ensure the accuracy and consistency of blood smear preparation. 4