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The Preoperative Bleeding Time Test: Assessing Its Clinical Usefulness

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The Preoperative Bleeding Time Test: Assessing Its Clinical Usefulness The preoperative bleeding time test: assessing its clinical usefulness AMY S. GEWIRTZ, MD; KANDICE KOTTKE-MARCHANT MD, PHD; MICHAEL L. MILLER, DO HE BLEEDING TIME is the The bleeding time test can aid in the diagnostic most commonly used evaluation of patients with clinical hemorrhagic disorders or test in the in vivo evalu- a history of bleeding. However, its low positive predictive ation of primary hemo- value in predicting perioperative bleeding should force one to T stasis. Although this test is known abandon it as a routine preoperative screening test. for its role in the evaluation of pa- tients suspected of having von INa'iiV Ji J Many methodologic factors affect the bleeding Willebrand's disease or abnormal time, including the length, depth, orientation, and location platelet function, it is quite often of the incision and whether a blood pressure cuff is used. The routinely ordered as part of preop- bleeding time also varies with age, sex, blood group, medica- erative screening to predict periop- tion use, skin characteristics, and diet. A prolonged bleed- erative bleeding in patients with ing time itself is nonspecific and is not pathognomonic of a no previous clinical signs of a single disease entity. Many studies have shown no associa- bleeding disorder. Physicians tion between a prolonged preoperative bleeding time and in- should be familiar with factors that creased perioperative blood loss. Even though a prolonged affect the standardization, reliabil- preoperative bleeding time usually lacks clinical significance, ity and specificity of the bleeding it often leads to additional laboratory tests, postponement of time test, as well as the pitfalls of surgery, increased length of stay, and possibly inappropriate using it to predict clinically signifi- treatment. cant perioperative bleeding. INDEX TERMS: BLEEDING TIME; PREOPERATIVE CARE; SENSITIVITY THE EVOLUTION OF THE AND SPECIFICITY CLEVE CLIN J MED 1995; 62:379-382 BLEEDING TIME TEST The bleeding time test was first described by Milian in 1901.1 In From the Departments of Anatomic Pathology (A.S.G.) and Clinical 1910, Duke2 introduced its use as Pathology (K.K.M., M.L.M.), The Cleveland Clinic Foundation. an in vivo measurement of the Address reprint requests to A.S.G., Department of Anatomic Pathology, L25, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, adequacy of platelet plug forma- OH 44195. tion, using the earlobe as the test site. Since then, several modifica- tions and variations have been in- troduced, mostly in an attempt to standardize the bleeding time and NOVEMBER • DECEMBER 1995 CLEVELAND CLINIC JOURNAL OF MEDICINE 379 Downloaded from www.ccjm.org on October 1, 2021. For personal use only. All other uses require permission. BLEEDING TIME TEST • GEWIRTZ AND ASSOCIATES increase its reliability. In 1941, Ivy et al3 suggested trates can be obtained from "nutrition centers," and the forearm be used as the site of testing and that a megadoses of these substances may prolong the blood pressure cuff be applied and inflated to 40 bleeding time.22 mm Hg to standardize venous return to the area. In 1969, Mielke et al4 improved upon Ivy's technique THE NONSPECIFICITY by using a template to help standardize the length OF A PROLONGED BLEEDING TIME and depth of the incision. In a complete departure from the other methods, Ratnoff5 devised a tech- A prolonged bleeding time in and of itself is nique that used the finger tip as the site of testing. nonspecific and not pathognomonic of a single dis- Today, most institutions use a modified Ivy tech- ease entity. In fact, it can be associated with either nique and commercially manufactured, disposable a quantitative or qualitative abnormality of any template devices with spring-loaded blades that element involved in primary hemostasis: platelets, make an incision of uniform length and depth. the vessel wall, collagen, or von Willebrand's fac- tor. The clinical conditions associated with an ab- MULTIPLE FACTORS AFFECT THE BLEEDING TIME normal bleeding time include quantitative and qualitative platelet disorders, anemia, vasculitis, Despite these improvements and modifications, uremia, hepatic dysfunction, von Willebrand's dis- the bleeding time test continues to be prone to ease, Ehlers-Danlos syndrome, severe hypofibrino- many technical problems that interfere with its genemia, myeloproliferative disorders, and parapro- standardization and reliability. Many factors affect teinemias. the reproducibility of the bleeding time. Test results are highly operator-dependent, with significant in- THE BLEEDING TIME teroperator variability.6 This reflects the technical AS A PREOPERATIVE SCREENING TEST difficulties inherent in the test methodology: the length, depth, orientation (vertical vs horizontal), Approximately half of the 1 to 2 million bleeding and location (volar aspect of the forearm vs antecu- time tests performed each year are ordered as part of bital fossa) of the incision can all affect the results, a preoperative evaluation to assess perioperative as can the use of a blood pressure cuff and the bleeding risk.23 The clinical use of the bleeding time characteristics of the skin (thickness, degree of un- in this fashion implies the acceptance of at least two derlying vascularity, and density of hair).7,8 Al- assumptions. The first is that superficial bleeding of though the introduction of a spring-loaded device the skin accurately reflects the potential for bleeding has standardized the length and depth of the inci- at other sites. However, O'Laughlin et al24 evaluated sion to some extent, the other variables remain, the effect of short-term and long-term aspirin use in making it difficult to derive a valid and clinically patients undergoing gastric biopsy and found no evi- useful bleeding time. dence that an increased skin bleeding time reflected The bleeding time also varies with age, sex, blood an increased gastric bleeding time. group, medication use, and diet.9"13 These factors The second assumption is that prolongation of the probably account for the wide variation in the bleeding time is clinically significant. Many studies bleeding time in the normal population. The bleed- and reviews that examined this question have dem- ing time is shorter in older people and in males and onstrated that the predictive value of the preopera- longer in people with type O blood. Ingestion of tive bleeding time is poor.25"27 Unfortunately, many aspirin commonly causes prolongation of the bleed- of these studies had limited usefulness: they lacked a ing time. Many other classes of medications also control group, did not use objective criteria to define interfere with platelet function; most commonly im- or measure intraoperative or postoperative bleeding, plicated are nonsteroidal anti-inflammatory drugs, or did not correlate bleeding time with other impor- antibiotics, anticonvulsants, cardiovascular drugs, tant indicators of platelet function. and ethanol.14,15 Several vitamins and spices have More recently, Gewirtz et al28 examined the pre- been reported to cause platelet dysfunction in vitro, dictive value of the preoperative bleeding time and including vitamins C and E, garlic, ginger, cumin, how it was used clinically in multiple surgical serv- and cloves.16"21 Although these do not usually cause ices. Although patients with a history of bleeding a problem when consumed in moderation, concen- were more likely to have an abnormal bleeding 380 CLEVELAND CLINIC JOURNAL OF MEDICINE VOLUME 62 • NUMBER 6 Downloaded from www.ccjm.org on October 1, 2021. For personal use only. All other uses require permission. BLEEDING TIME TEST • GEWIRTZ AND ASSOCIATES time, there was no statistically significant associa- statistically significant correlation between inges- tion between an abnormal bleeding time and pe- tion of medications known to interfere with platelet rioperative bleeding or use of blood products. The function and prolonged bleeding time or significant positive predictive value of the routine preoperative perioperative bleeding. bleeding time for predicting perioperative bleeding was only 5%.28 IS THERE A CLINICAL ROLE FOR THE PREOPERATIVE BLEEDING TIME TEST? The association between platelet dysfunction and perioperative blood loss has been investigated in a variety of surgical settings. Owing to the use of car- Before surgery, patients with a clinical history of diopulmonary bypass, cardiovascular procedures excessive bleeding may deserve a hematologic have a deleterious effect on platelets, and periopera- evaluation that includes a bleeding time test. How- tive bleeding has been extensively investigated in ever, many investigators in various disciplines have this patient population. Simon et al29 found that demonstrated that routine preoperative testing of "...thrombocytopenia and prolongation of bleeding the bleeding time lacks predictive value in assessing time did not correlate with blood loss or transfusion the risk of perioperative bleeding. needs." Burns et al30 concluded that there was no An abnormal bleeding time presents the labora- correlation between the bleeding time and either tory, clinician, and hospital with many problematic the decrease in hemoglobin concentration or the issues, all of which contribute to increased utiliza- amount of chest-tube drainage after surgery. Their tion of resources and higher health care costs. The findings have been supported by many others in far-reaching effects of an abnormal result can, de- both prospective and retrospective studies.31"33 pending on
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