Bloodletting

Bloodletting (or blood-letting) is the withdrawal of blood from a patient to prevent or cure illness and disease. Bloodletting, whether by a physician or by leeches, was based on an ancient system of medicine in which blood and other bodily fluids were regarded as 'humours' that had to remain in proper balance to maintain health. It is claimed to have been the most common medical practice performed by surgeons from antiquity until the late 19th century, a span of almost 2,000 years. In Europe the practice continued to be relatively common until the end of the 18th century. The practice has now been abandoned by modern style medicine for all except a few very specific conditions. It is conceivable that historically, in the absence of other treatments for hypertension, bloodletting sometimes had a beneficial effect in temporarily reducing blood pressure by reducing blood volume. However, since hypertension is very often asymptomatic and thus undiagnosable without modern methods, this effect was unintentional. In the overwhelming majority of cases, the historical use of bloodletting was harmful to patients.One typical course of medical treatment began the morning of 13 July 1824. A French sergeant was stabbed through the chest while engaged in single combat; within minutes, he fainted from loss of blood. Arriving at the local hospital he was immediately bled twenty ounces (570 ml) 'to prevent inflammation'. During the night he was bled another 24 ounces (680 ml). Early the next morning, the chief surgeon bled the patient another 10 ounces (285 ml); during the next 14 hours, he was bled five more times. Medical attendants thus intentionally removed more than half of the patient's normal blood supply—in addition to the initial blood loss which caused the sergeant to faint. Bleedings continued over the next several days. By 29 July, the wound had become inflamed. The physician applied 32 leeches to the most sensitive part of the wound. Over the next three days, there were more bleedings and a total of 40 more leeches. The sergeant recovered and was discharged on 3 October. His physician wrote that 'by the large quantity of blood lost, amounting to 170 ounces (4.8 liters), besides that drawn by the application of leeches (1.1 liters), the life of the patient was preserved'. By nineteenth-century standards, thirteen pints of blood taken over the space of a month was a large but not an exceptional quantity. The medical literature of the period contains many similar accounts-some successful, some not.The opening of the superficial vessels for the purpose of extracting blood constitutes one of the most common operations of the practitioner. The principal results, which we effect by it, are 1st. The diminution of the mass of the blood, by which the overloaded capillary or larger vessels of some affected part may be relieved; 2. The modification of the force and frequency of the heart's action; 3. A change in the composition of the blood, rendering it less stimulating; the proportion of serum becoming increased after bleeding, in consequence of its being reproduced with greater facility than the other elements of the blood; 4. The production of syncope, for the purpose of effecting a sudden general relaxation of the system; and, 5. The derivation, or drawing as it is alleged, of the force of the circulation from some of the internal organs, towards the open outlet of the superficial vessel. These indications may be fulfilled by opening either a vein or an artery. Bloodletting (or blood-letting) is the withdrawal of blood from a patient to prevent or cure illness and disease. Bloodletting, whether by a physician or by leeches, was based on an ancient system of medicine in which blood and other bodily fluids were regarded as 'humours' that had to remain in proper balance to maintain health. It is claimed to have been the most common medical practice performed by surgeons from antiquity until the late 19th century, a span of almost 2,000 years. In Europe the practice continued to be relatively common until the end of the 18th century. The practice has now been abandoned by modern style medicine for all except a few very specific conditions. It is conceivable that historically, in the absence of other treatments for hypertension, bloodletting sometimes had a beneficial effect in temporarily reducing blood pressure by reducing blood volume. However, since hypertension is very often asymptomatic and thus undiagnosable without modern methods, this effect was unintentional. In the overwhelming majority of cases, the historical use of bloodletting was harmful to patients. Today, the term phlebotomy refers to the drawing of blood for laboratory analysis or blood transfusion. Therapeutic phlebotomy refers to the drawing of a unit of blood in specific cases like hemochromatosis, polycythemia vera, porphyria cutanea tarda, etc., to reduce the number of red blood cells. The traditional medical practice of bloodletting is today considered to be a pseudoscience. Passages from the Ebers Papyrus may indicate that bloodletting by scarification was an accepted practice in Ancient Egypt. Egyptian burials have been reported to contain bloodletting instruments.According to some accounts, the Egyptians based the idea on their observations of the Hippopotamus, confusing its red sweat with blood, and believing that it scratched itself to relieve distress. In Greece, bloodletting was in use in the fifth century BC during the lifetime of Hippocrates, who mentions this practice but generally relied on dietary techniques. Erasistratus, however, theorized that many diseases were caused by plethoras, or overabundances, in the blood and advised that these plethoras be treated, initially, by exercise, sweating, reduced food intake, and vomiting. Herophilus advocated bloodletting. Archagathus, one of the first Greek physicians to practice in Rome, also believed in the value of bloodletting. 'Bleeding' a patient to health was modeled on the process of menstruation. Hippocrates believed that menstruation functioned to 'purge women of bad humours'. During the Roman Empire, the Greek physician Galen, who subscribed to the teachings of Hippocrates, advocated physician-initiated bloodletting. The popularity of bloodletting in the classical Mediterranean world was reinforced by the ideas of Galen, after he discovered that not only veins but also arteries were filled with blood, not air as was commonly believed at the time. There were two key concepts in his system of bloodletting. The first was that blood was created and then used up; it did not circulate, and so it could 'stagnate' in the extremities. The second was that humoral balance was the basis of illness or health, the four humours being blood, phlegm, black bile, and yellow bile, relating to the four Greek classical elements of air, water, earth, and fire respectively. Galen believed that blood was the dominant humour and the one in most need of control. In order to balance the humours, a physician would either remove 'excess' blood (plethora) from the patient or give them an emetic to induce vomiting, or a diuretic to induce urination. Galen created a complex system of how much blood should be removed based on the patient's age, constitution, the season, the weather and the place. 'Do-it-yourself' bleeding instructions following these systems were developed. Symptoms of plethora were believed to include fever, apoplexy, and headache. The blood to be let was of a specific nature determined by the disease: either arterial or venous, and distant or close to the area of the body affected. He linked different blood vessels with different organs, according to their supposed drainage. For example, the vein in the right hand would be let for liver problems and the vein in the left hand for problems with the spleen. The more severe the disease, the more blood would be let. Fevers required copious amounts of bloodletting. The Talmud recommended a specific day of the week and days of the month for bloodletting, and similar rules, though less codified, can be found among Christian writings advising which saints' days were favourable for bloodletting. During medieval times bleeding charts were common, showing specific bleeding sites on the body in alignment with the planets and zodiacs. Islamic medical authors too advised bloodletting, particularly for fevers. It was practised according to seasons and certain phases of the moon in the lunar calendar. The practice was probably passed by the Greeks with the translation of ancient texts to Arabic and is different than bloodletting by cupping mentioned in the traditions of Muhammad. When Muslim theories became known in the Latin-speaking countries of Europe, bloodletting became more widespread. Together with cautery, it was central to Arabic surgery; the key texts Kitab al-Qanun and especially Al-Tasrif li-man 'ajaza 'an al-ta'lif both recommended it. It was also known in Ayurvedic medicine, described in the Susruta Samhita.