The Chinese surgeon who was already operating with anesthesia more than 600 years ago

Xia Quan was a highly valued Chinese physician. And that is why in 1411, when he died, during the Ming dynasty, he was buried with some of the instruments he had used. It was a usual practice in China, both to pay honor to his quality and so that he could practice his profession in the afterlife.

That tribute has made it possible, six centuries later, to demonstrate that Xia Quan was even more advanced than could have been supposed. His tools have provided the first direct evidence of the use of an anesthetic in a surgical intervention.

There are several written documents that explain the use of substances such as opium or alcohol to prevent or reduce pain since antiquity (see box). But this would be the first case in which the presence of a natural component, conveniently treated to avoid serious side effects, would have been identified.

Residue analyses on archaeological objects help to identify traces of specific compounds in instruments. Thus, in a ship that sank around 130 BC off the coast of Tuscany, some tablets were found containing zinc oxide, pine resin, and beeswax, probably for use in ophthalmology. And much older remains, identified in ceramic vessels from a mummification workshop of the 26th dynasty (7th and 6th centuries BC) in Saqqara (Egypt), contained remains of pistachio resin and beeswax, which were used for their antibacterial properties.

Now, a team led by Congcang Zhao, from Northwest University of China, and Zheng Li, from the National Archaeology Centre of the Asian country, have made use of the instruments found in 1974 in a tomb in Jiangsu province, in southeastern China, which was a prominent center of medical practice during the Ming (1368-1644) and Qing (1644-1912) dynasties. These are the few medical instruments that can be attributed to a specific physician: Xi Quan.

These are a pair of scissors and forceps that are preserved in the Jiangyin Museum. First, the authors observed, using X-ray fluorescence, that the instruments were made with iron alloys with more than 95% of this metal, with the presence also of copper, lead, cobalt, and even chromium, titanium, and other elements. This reveals precise knowledge of the local iron industry regarding these materials and their properties. The design also clearly shows a remarkable level for the time.

Subsequently, to comply with antiquities protection law, researchers conducted a small, minimally destructive extraction and collected a sample of only 2 milligrams. In areas of instruments that are difficult to clean, such as where the blades of scissors overlap, it is more feasible to find residues. They applied an advanced optical technique called stimulated Raman effect to the small sample ("Stimulated Raman scattering or SRS). It combines spectroscopy and the Raman effect, which is based on the scattering of a beam of visible radiation that passes through a medium and does so differently depending on the compounds it encounters.

A toxic alkaloid as an anesthetic

This allowed the identification of traces of aconitine, a very toxic alkaloid present in plants of the genus Aconitum, such as blue monkshood. These plants are highly toxic, even deadly. While written documents contain references to the use of these plants to alleviate pain and even as an anesthetic, this is the first evidence of the effective presence of this compound in medical instruments. Through comparative tests, the authors have deduced that, specifically, the substance would come from the species Aconitum carmichaelii.

The finding reveals sufficient knowledge to isolate aconitine and to transform it and use it in the correct doses to avoid its severe toxic effects. According to the authors, at that time Chinese physicians used various methods to reduce the toxicity of aconitine, such as mixing it with urine, submerging it in a black soybean decoction, boiling it in vinegar, or removing the root peel. This produced an anesthetic called Caowu San, present in various treatises.

In the history of Chinese medicine, there are references to another anesthetic. According to some documents from the 3rd and 5th centuries, such as the Records of the Three Kingdoms and the Book of the Later Han, the physician Hua Tuo, who lived between the years 140 and 208, performed surgery with an anesthetic called mafeisan. This name combines ma, which means hemp, fei, which means to boil, and san, which can refer to a medicine in powder form. Thus, mafeisan likely meant 'boiled hemp powder'. Hua Tuo would have dissolved it in wine to administer it. However, there is no evidence of its actual composition, as the physician burned all his manuscripts before dying. And the aforementioned documents do not mention its components.

Fortunately for historians, while Hua Tuo burned his papers, the preservation of instruments belonging to illustrious physicians in their tombs allows for other types of research. In this case, researchers have found direct chemical evidence that a Chinese physician used an anesthetic before operating, more than 400 years before demonstrations were made in England on the utility of ether and chloroform to prevent pain during surgical intervention.