Hemalabexp 4 - Lecture notes 1 PDF

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ALEJOS, CAMILLE JOY R. 0958FL

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EXPERIMENT 4 - CAPILLARY FRAGILITY TEST

III) Wrap a blood pressure cuff around the patient's arm. Draw a circle on the patient's forearm. Inflate the blood pressure cuff for 5 minutes. Observe for petechiae.

I) Patient Identification

I Preparation of Equ to be used. Ballpen is used in drawing a for petechiae observation and for marking previously present petechiae.

IV)Record and grade petechiae results Presence of more than 20 petechiae is considered a positive test. The test result may be graded roughly as follows: (0-10) 1+ = a Few petechiae on the anterior part of the forearm (10-20) 2+ = Many petechiae on the anterior part of the forearm (20-50) 3+ = Multiple petechiae over the whole arm and back of the hand (over 50) 4+ = Confluent petechiae on the arm and back of the hand

QUESTIONS FOR RESEARCH: 1. State the principle and clinical significance of the test. Principle: Capillary Fragility Test (Rumpel-Leede Capillary-Fragility Test/ Tourniquet test) is a positive pressure technic involving partial occlusion of the circulation of an extremity that utilizes a blood pressure cuff. Stasis is produced by inflating a sphygmomanometer cuff around the arm with the appropriate pressure for 5 minutes. Increase in intracapillary hemostatic pressure produces petechiae distal to the point of occlusion in patients with certain diseases. The 2.5 cm diameter region of skin on the volar surface of the arm 4 cm distal to the antecubital fossa is observed for petechial haemorrhages. The factors associated with capillary fragility are the pressure of blood in the vessels, the character of the blood itself such as platelet and coagulation defects, and finally the character of the capillary wall, morphologically and functionally. Thought his test is non-specific, it is still clinically significant because: o It can measure the degree of thrombocytopenia o It can identify whether there is an intrinsic defect in the capillary walls of the patients or none o It can help identify whether there are decreased factors for maintaining vascular integrity

o

Can determine other hematologic diseases

2. What are the physiologic factors and sources of error that may affect the test? o Prolonged application – it may most likely lead to false positive results o Age – elders tend to have a declining ability of cellular regeneration and vascular integrity. Thus, it is more likely that they have increased petechiae. o Skin blemishes, previously existed petechiae – this can be addressed by marking the pigmented areas with an inkmark prior to test to avoid confusion. o Diabetes with hypertension or other vascular diseases – diabetes has the capability to stimulate the release of inflammatory markers thereby causing a false positive test result. o Other factors o Prolonged use of streoids, premenstrual periods, postmenstrual periods – increases capillary fragility test results. 3. What are other methods of capillary fragility testing? Describe how they are performed and summarize their grading scale. Other Methods How they are performed Grading scale 1) The forearm is introduced to a BP cuff with a pressure that is midway between systolic and Modification of diastolic blood pressure for 5-10 minutes. Rumpel2) Examine the representative area which is 2.5 cm Leede’s test below the BP cuff. Mark petechiae with circles of 1” in diameter. 1) Two forearms as representative areas will be Abnormal CFT result: Greater than 12 introduced to sphygmomanometer with 35mmHg Gothlin pressure for 15 minutes. Technique Normal: 8 and below 2) Count the representative area for petechial hemorrhage 1) A suction cup is applied to the area (1-2 cm) to be tested in order to maintain a given degree of Negative negative pressure of 200 to 250 torr for either 30 Pressure Test seconds or one minute. 2) Count the number of petechiae produced in the area of suction. 1) A tourniquet is put around the arm for five minutes. 2) On the fourth minute of tourniquet pressure: Control area: may be done just above the tourniquet on the Capillary Flick arm. Normal: 0 to 10 petechiae Test Test area: the distended veins of the elbow are flicked twice by the thumb and middle finger of the examiner. 3) After the release of the tourniquet, the petechiae in the elbow area are counted. 1) The distant portion of the little finger is squeezed for two minutes by the thumb and forefinger of the Warkany examiner Pressure Test 2) The number of petechiae visible on the flexor surface of the tip of the little finger is counted. 1) The thumb and index finger are used to pinch Hecht's Petechiae may be indicative of scarlet patient’s chest for 5-10 s "pinching" test fever 2) Release pinch. on the trunk 3) Observe for petechiae. 4. What is the role of platelets in maintaining vascular integrity? Platelets maintain the normal vascular integrity by providing nourishment to the endothelium or at some points, their actual incorporation into the vessel wall. It is because even if the platelets are present in normal quantities but can’t function properly due to deficiencies, hemostasis won’t occur. Platelets respond to vascular damage by its rapid adherence to exposed endothelium forming a platelet plug to initially arrests bleeding. The adherence and aggregation of platelets at the sites of vascular damage allow for the release of molecules involved in hemostasis and wound healing and provide a membrane surface for the assembly of coagulation enzymes that lead to fibrin formation. Vascular healing is promoted by stimulating the migration and proliferation of endothelial cells and medial smooth muscle cells through the release of the mitogen, platelet-derived growth factor.

REFERENCES:  Goldman, L., & Corrill, E. M. (1945). Studies in some capillary fragility states in dermatology. Journal of Investigative Dermatology, 6(2), 129-147. https://doi.org/10.1038/jid.1945.12 

Perry, D. J., & Linden, I. H. (1953). Studies of methods of determining capillary Fragility1. Journal of Investigative Dermatology, 20(4), 251-256. https://doi.org/10.1038/jid.1953.31

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Turgeon, M. L. (2012). Clinical hematology: Theory and procedures (5th ed.). Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins....