van Helmont's proposal for a randomised comparison of treating fevers with or without bloodletting and purging.

Around the year 1643, Joan Baptista van Helmont, a Flemish chemist, alchemist and physician who had devised what he claimed to be a new form of medicine, proposed a 'challenge' to traditional Galenic physicians to compare treatment of fever by traditional methods and by a regime which did not involve bloodletting and purging. Two groups of patients were to be treated and 'casting of lots' was to be used - in some way not specified in detail - to decide who received which treatment. This 'challenge' has been regarded as the first proposal for the use of randomisation in a clinical trial. This paper explains the background to the challenge and discusses what can be deduced from Helmont's text about the details of how he proposed that the 'trial' was to be carried out. It concludes that internal evidence in Helmont's writings makes it certain that no such 'trial' was ever conducted. It seems that the 'challenge' was probably a rhetorical device to support Helmont's vehement criticism of traditional Galenic medicine and its practitioners, and, in particular, toemphasise his absolute opposition to the use of bloodletting as a medicaltreatment. An appendix includes a short summary of Helmont's theories of the origins of disease and transcriptions of the passages of Helmont's Latin text translated in the article.

Using the numerical method in 1836, James Jackson bridged French therapeutic epistemology and American medical pragmatism.

OBJECTIVES: To review James Jackson's analysis of bloodletting among pneumonitis patients at the newly founded Massachusetts General Hospital, in which he implemented the numerical method advocated by Pierre-Charles-Alexandre Louis. STUDY DESIGN AND SETTING: The study sample included 34 cases of clinically diagnosed pneumonitis admitted to Massachusetts General Hospital between April 19, 1825, and May 10, 1835, and discharged alive. Patient data were extracted from meticulously kept case books. Jackson calculated mean number of venesections, ounces of blood taken, and days of convalescence within groups stratified by day of the disease when first bloodletting occurred. He also calculated average convalescence within groups stratified by age, sex, prior health, vesication, and day of the disease when the patients were admitted to the hospital. RESULTS: To Jackson's surprise, it "seemed to be of less importance, whether our patients were bled or not, than whether they entered the hospital early or late" after the onset of the pneumonitis. Bloodletting was ineffective. Our multivariate reanalysis of his data confirms his conclusion. Outstandingly for his time, Jackson ruled out unwarranted effects of covariates by tabulating their numerical relations to the duration of pneumonia. CONCLUSION: Using novel gathering of patient clinical data from hospital records and quantitative analytical methods, Jackson contributed results that challenged conventional wisdom and bridged French therapeutic epistemology and American medical pragmatism.

[Research of bleeding volume and method in blood-letting acupuncture therapy based on data mining].

Through computer-based technology and data mining method, with treatment in cases of bloodletting acupuncture therapy in collected literature as sample data, the association rule in data mining was applied. According to self-built database platform, the data was input, arranged and summarized, and eventually required data was acquired to perform the data mining of bleeding volume and method in blood-letting acupuncture therapy, which summarized its application rules and clinical values to provide better guide for clinical practice. There were 9 kinds of blood-letting tools in the literature, in which the frequency of three-edge needle was the highest, accounting for 84.4% (1239/1468). The bleeding volume was classified into six levels, in which less volume (less than 0.1 mL) had the highest frequency (401 times). According to the results of the data mining, blood-letting acupuncture therapy was widely applied in clinical practice of acupuncture, in which use of three-edge needle and less volume (less than 0.1 mL) of blood were the most common, however, there was no central tendency in general.

The effect of arterial lines on blood-drawing practices and costs in intensive care units.

STUDY OBJECTIVE: To determine whether the presence of an indwelling arterial access line leads to differences in blood-drawing practices and costs, in patients with similar APACHE II scores, in the ICU. DESIGN: Prospective, observational. SETTING: Adult surgical and medical ICUs at a large military tertiary care hospital. PATIENTS: Twenty-five adult (ie, above 18 years old) patients with arterial access lines and 25 adult patients without arterial access lines. Each had APACHE II of 9 to 20 and none had any central venous access. MEASUREMENTS AND RESULTS: A survey of the arterial line blood-drawing habits of critical care nurses at our hospital revealed a 2.99-mL mean discard blood volume to clear an arterial line, with only 9.4% not discarding any blood. For each patient enrolled in the study, the number of blood tests and blood draws were recorded during the first two 24-h periods after admission to the ICU. The amount of blood required by the laboratory for each blood test was totalled. In the arterial line group, the mean discard volume was added to the total for each blood-drawing procedure. Increases were found in the number of blood tests (29% increase, p = 0.013), blood-drawing procedures (30% increase, p = 0.014), and the amount of blood volume (44% increase, p < 0.001) sent from patients with arterial lines compared to those without. CONCLUSION: When APACHE II scores are similar, the presence of an arterial access line may lead to increased blood drawing from patients in ICUs.

The seroepidemiology of human immunodeficiency virus in the United States household population: NHANES III, 1988-1991.

To provide an estimate of the seroprevalence of human immunodeficiency virus (HIV) in a representative sample of the U.S. household population, serum samples from participants in the third National Health and Nutrition Examination Survey (NHANES III) were tested for HIV antibody. The testing was performed anonymously on 5,430 individuals 18-59 years old from phase 1 of NHANES III conducted from 1988 to 1991. Twenty-nine individuals were HIV positive. The total weighted prevalence was 0.39%. The population estimate of infected individuals was 547,000, with a 95% confidence interval of 299,000-1,020,000 infected persons. Black participants were four times more likely to be HIV positive than white/other individuals and three times more likely than Mexican Americans. Men were three times more likely to be infected than women. Higher nonresponse to the survey and to phlebotomy was observed in young white men; therefore these data provide a conservative estimate of HIV infection in the general household population. This estimate does not include individuals who do not live in households and who may be at higher risk of infection, such as persons in penal institutions, the homeless, or certain hospitalized patients.

A study of needle stick injuries among medical undergraduates.

A study was conducted to determine the incidence and causes of needlestick injuries among 158 medical undergraduates who had completed their first clinical year. A response rate of 97.5% (154 out of 158 students) was obtained, of which 54 students (35.1%) reported at least one needlestick injury. The commonest cause of injury was during the process of venepuncture (27%), followed by uncapping of needles (22.2%) and recapping of used needles (19.8%). The highest incidence of injury occurred during a medical posting (33/154 students), followed by surgical posting (14/154 students) and elementary clinics (9/154 students). Formal training on handling of used needles was reported by only 15-23% of the students in the various postings. The awareness of risk of contracting diseases from needlestick injuries was high (84.4%).

Phlebotomy--a minimalist approach.

For each patient, laboratories usually collect more blood than is needed for specific determinations. We reviewed the amount of blood collected for laboratory measurements for an entire hospital stay of 113 patients admitted during a 1-week period to a medical ward or to a medical intensive-care unit in our tertiary-care facility. The amount of blood obtained was also compared with the minimal amount needed for analysis for 18 of the most frequently ordered laboratory tests in our facility. For routine collections, a mean of 45 times the required volume of specimen (range, 2 to 102 times) was obtained. For optimal utilization of laboratory services, both the positive and the negative consequences of testing must be thoughtfully considered. Two potential adverse effects of withdrawal of blood for laboratory determinations are iatrogenic anemia and infection. Moreover, the cost of care is increased with additional analyses. Practical strategies for decreasing the amount of blood collected include an increased awareness of ordering practices, a thorough knowledge of the volume of blood needed for each laboratory test, experienced phlebotomy personnel, storage of blood specimens for potential subsequent use, and communication of accurate minimal volumes needed for specific measurements.

A prospective study evaluating the lowering of hemoglobin standards for blood donors.

Strict regulations exist for the selection of blood donors. These include minimum hemoglobin (Hb) standards of 13.5 and 12.5 g/dL for males and females respectively. In Canada 2% of all blood donors, or approximately 25,000 individuals annually attempt to make a blood donation but are deferred because their Hb level does not meet these minimum accepted standards. In a previous study we provided a biostatistical approach to ascertain objectively the optimal minimum Hb standards for blood donors to best discriminate between iron deficient and non iron deficient individuals. The derived values were lower than the existing minimum Hb standards and because of concern that blood donors accepted using these lower Hb standards might have asymptomatic disease, the proposed new levels were not adopted. This present prospective study was undertaken to assess the impact on the blood donors of the new Hb standards. Over 26 months we evaluated 1,558 donors (695 males and 863 females). On entry into the study they were screened for a variety of medical conditions which could result in asymptomatic anemia and 6 months later they answered a health questionnaire. Blood donors were entered into 1 of 3 groups. Group I were donors accepted by the existing criteria. Group II were donors who did not meet the existing Hb criteria but satisfied the newly derived standards. Group III were donors deferred even by the new Hb standards.(ABSTRACT TRUNCATED AT 250 WORDS)

Phlebotomy for diagnostic laboratory tests in adults. Pattern of use and effect on transfusion requirements.

Although anemia is a frequently observed complication of phlebotomies for laboratory tests in neonates, this problem has received little attention in adult populations. We analyzed the phlebotomy records of 100 hospitalized patients and found that 50 patients who spent all of their hospitalization in general wards had blood samples drawn an average of 1.1 times a day. A mean volume of 12.4 ml a day was drawn, and the total volume drawn during their entire hospitalization was 175.0 ml. In contrast, 50 patients who spent part or all of their hospitalization in an intensive care unit were phlebotomized a mean of 3.4 times a day, for a mean volume of 41.5 ml of blood drawn a day and a total volume of 762.2 ml. Patients in the intensive care unit who had arterial lines had more blood drawn (944.0 ml), more often (4.0 times a day), than patients in the intensive care unit who did not have such lines (300.9 ml; 1.9 times a day). Of 36 patients who received transfusions, 17 (47 percent) had large losses from phlebotomy (greater than 180 ml of red cells) that contributed to their transfusion requirements. We propose the use of sample tubes of the size used in pediatrics, batching of requests for laboratory tests, and review of the cumulative volume of blood removed from individual patients as approaches to reducing blood loss from phlebotomy.