Written by Celyn Matienzo
Image by István Asztalos from Pixabay
As our knowledge of science and healthcare continues to expand, our medical techniques and practices also change accordingly. Just as often as techniques are improved, so too can they be rendered obsolete. The latter is the case with bloodletting, an old medical practice that we often associate with medieval times or the Dark Ages.
“Bloodletting” was a medical technique used in the 19th century that involved removing blood from a patient as a means of curing a number of seemingly unrelated medical conditions [1]. The reason that medical practitioners in the past thought that the removal of blood might be useful in treating various diseases and complaints was because of the prevalent medical paradigm. At the time, the human body was thought to be composed of the four elements of water, air, fire, and earth, and each of these elements was controlled by fluids called the “humors,” which included yellow bile, black bile, phlegm and blood [1]. Doctors at the time thought that curing diseases involved balancing the humors by partaking in certain practices such as removing blood. The practice of bloodletting also followed the “stimulus, contra-stimulus” theory that informed medical practices. A contra-stimulus such as bloodletting was a stimulus that was meant to oppose the inflammation that the body was experiencing naturally, simulating the already-stimulated site in order to counteract and cure the underlying disease.
There were a number of bloodletting techniques that were commonly used. Arteriotomy involved cutting into an artery, usually with a lancet or fleam, which are comparable to scalpels that surgeons use today, to make an incision, or scarification which involved scraping the skin with a box-shaped device whose surface was embedded with knife blades [1]. For some treatments, blood needed to be drawn from specific areas of the body. In the case of localized bloodletting, leeches were placed on the affected area, taking anywhere from 5 to 10 of ounces of blood at a time, several times the leech’s body weight [1].
Bloodletting naturally brought a number of problems, many of which were evident to scientists and medical practitioners, even during the period in which bloodletting was still in common use [5]. Various tests had been conducted that demonstrated the inefficiency of bloodletting, proving the technique to be less helpful than had previously been thought [1]. On top of having an ineffective treatment, the instruments involved in the procedure could cause problems. A spring lancet, while convenient, was difficult to clean and this often led to contamination and the spread of disease from patient to patient [2].
Bloodletting is still present in principle, evident in the occupation of “phlebotomists,” who take blood from patients, though usually in order to prepare it for testing in a lab rather than for simply removing blood as a cure. Bloodletting is sometimes used in experimental circumstances, such as testing the efficiency of a bone plug implant in mice in the regeneration of red blood cells [4]. Blood-related diseases, such as hemochromatosis and polycythemia vera, involve abnormal regulations of blood or components in the blood like iron, and in these cases, the withdrawal of small amounts of blood can help in treatment or prevention. Even leeches are sometimes used today, particularly in reconstructive or reattachment surgery to prevent clotting in reattached veins and arteries [5]. Even though bloodletting itself is dangerous, it has assisted in the development of a few useful techniques still in use today.
References:
1. BCMJ – The history of bloodletting; Vol 52, No. 1, January, February 2010; p 12-14
2. AJG – Spring Lancet, Robert E. Kravetz; (2003), vol 98
3. The Journal of Antibiotics – From milk to rifampicin and back again: history of failures and successes in the treatment for tuberculosis, Michele A. Riva (2014) vol 67, p 661-665, 6 August 2014
4. BoneKEy Reports (2012), Anna Teti – “Table 1: Major findings on the interplay between osteoclasts and hematopoiesis”, Volume 1, Article 46, 28 March 2012
5. Nature, Suckers for success; vol 484, p 416, 26 April 2012