Manual of basic techniques for a health laboratory - libdoc.who.int

9. Haematology 295Very high ESR values occur in tuberculosis, trypanosomiasis and malignant diseases.The ESR is also raised in pregnancy.9.8 Measurement of the bleeding time: Duke method9.8.1 PrincipleA small cut is made with a lancet in the lobe of the ear. Blood flows from thepuncture and the time it takes for the bleeding to stop is measured.The test is performed:— for the diagnosis of certain haemorrhagic disorders;— before surgical operations;— before puncture of the liver or spleen.9.8.2 Materials and reagents●●●●●Sterile blood lancetsMicroscope slidesFilter-paper (or blotting paper)Stopwatch, if available, otherwise a watch with a second handEther.9.8.3 Method1. Gently clean the lobe of the ear with cotton wool and ether (Fig. 9.50). Do notrub. Allow to dry.2. Puncture the ear lobe (Fig. 9.51). The blood should flow freely, without anyneed to squeeze the ear lobe. Start the stopwatch.3. After 30 seconds collect the first drop of blood on a corner of the filter-paper (orblotting paper) (Fig. 9.52). Do not touch the skin with the paper.4. Wait 30 seconds more. Collect the second drop of blood in the same way, a littlefurther along the strip of paper (Fig. 9.53).Fig. 9.50 Cleaning the ear lobe withetherFig. 9.51 Puncturing the ear lobe