Brief History of Medicine Flashcards
Who was Imhotep?
Records show he was the first recorded physician in history (2600BC)
Authored medical treatise, the’ Edwin Smith Surgical Papyrus’ which contained anatomical observations, ailments and cures
Describe the rationalisation of Medicine with Hippocrates
Hippocrates (460-370BC) was a Greek physician, considered to be the father of medicine, principally because he laid the foundation for a rational approach to Medicine
He dismissed the idea that illness could be mystical, preferring to explain disease as the product of environmental factors, diet and living habits
His theories (although in hindsight incorrect anatomy and physiology) include the concept of humourism; which stated that the human body was filled with four basic substances, called humours, which are in balance when a person is healthy
The 4 humours were black bile, yellow bile, phlegm and blood
All diseases and disabilities supposedly resulted from an excess or deficit of one of these four humours, caused by vapours inhaled or absorbed by the body. This theory dominated the western world for over 1300 years
Famous for setting out the duties and responsibilities of a doctor - the Hippocratic Oath, introduces:
- The notion of free access to care
- The principle of beneficence (acting in the interest of the patient)
- The principle of non-maleficence (not harming the patient)
- The principle of confidentiality
What were some medical advancements in the roman empire?
Roman physician Galen of Pergamon (AD 129-200) supported humourism, performed brain and eye surgery
Galen made use of direct observation, dissection and vivisection
Roman law prohibited the dissection of human cadavers from 150BC, Galen performed anatomical dissections on living (vivisection) and dead animals, mainly pigs and primates which closely mirrored humans
Galen clarified the anatomy of the trachea and was the first to demonstrate that the larynx generated the voice
He was also the first to recognise that there were distinct differences between venous (dark) and arterial (bright) blood, explained the difference between motor and sensory nerves and discussed the concept of muscle tone
The Romans were the first civilisation to:
- introduce a true public health system
- constructed aqueducts to bring water into the city
- built public baths to ensure sanitation as well as set up an underground sewage system
- public lavatories flushed by fresh clean water
- drained marshes to get rid of malaria-carrying mosquitoes
What were some medical advancements in the Middle Ages (AD 750)?
All works written by the fathers of Medicine (Imhotep, Hippocrates, Galen) were translated into Arabic and used by Islamic physicians for research
Physicians such as Muhmmad ibn Zariya Razi (commonly known as Rhazes) (AD 865-925) started querying the validity of the humourism theory. Rhazes was a prolific authored, having written over 200 books, and is credited for being the first to differentiate smallpox from measles and for the discovery of numerous compounds and chemicals including alcohol.
Rhazes advised practitioners to keep up with advanced knowledge by continually studying medical books and exposing themselves to new information
The Middle Ages also witnessed the introduction of hospitals and medical schools
The Mediaeval hospital encompassed hostels for travellers, dispensaries for the poor, clinics and surgery for the injured, and homes for the blind, lame, elderly and mentally ill.
Monastic Hospitals developed treatments, both therapeutic and spiritual. Led by monasteries, providing medical care for sick pilgrims and victims of numerous plagues and chronic diseases. Thought to be a French invention, hospitals began to appear in great numbers in France and England following the French Norman invasion into England
The 14th and 15th centuries saw a major shift in medical thinking, with the rejection of the ‘traditional authority’ approach to Medicine, whereby if someone in authority had said something in the past then it had to be true, in favour of a more evidence-based approach
What were some medical advancements in the 16th and 17th centuries?
Hierarchy:
During the Renaissance period (14th-17th century), academically trained doctors in medical faculties at universities figured prominently in defining medical guilds and accepted practices as well as the required qualifications for physicians
University-educated physicians and other practitioners were organised according to a strict hierarchy:
- with university educated physicians on top
- followed by learned surgeons; craft-trained surgeons; barber surgeons (blood-letting); itinerant (travelling) specialists such as dentists and oculists; empirics (observation and experiments); midwives; clergy (dispensed charitable advice and help)
- and finally ordinary family and neighbours
Each of these groups practised Medicine in their own capacity and contributed to the overall culture of Medicine, sometimes in very dubious ways, E.g. the retention of the humourism theory meant that practices such as blood-letting using leeches, which did more harm than good to a patient, were common
Leonardo da Vinci:
Da Vinci’s (1452-1519) approach to science was based on detailed observation. He participated in several autopsies and created many detailed anatomical drawings, planning a major work of comparative human anatomy
Girolamo Fracastoro (1478-1553):
The Italian, Fracastoro suggested that epidemic diseases might be caused by objects outside of the body that could be transmitted by direct or indirect contact. He also proposed new treatments for diseases such as syphilis
Andreas Vesalius:
The Flemish Scholar in 1543 wrote the first complete textbook on human anatomy
Paracelsus:
In the 16th century, discovered that illness was caused by agents outside the body such as bacteria, not by imbalances within the body
Ambroise Pare:
French army doctor. Revived the ancient Greek method of tying off blood vessels after amputation, commonly cauterise the open end of the amputated appendage to stop the haemorrhaging
Pare also believed in dressing wounds with clean bandages and ointments, including one he made himself composed of eggs, oil of roses and turpentine
He was the first to design artificial hands and limbs for amputation patients
William Harvey:
Englishman. In 1628 explained the circulation of blood through the body in veins and arteries and found that blood was pumped around the body by the heart. It was previously thought that blood was the product of food and was absorbed by muscle tissue
Richard Lower and Robert Hooke:
Later showed through experimentation that the blood “picked up something” on its way through the lungs, which turned its colour to bright red (it is only in the 18th century, the French chemist Lavoisier discovered oxygen)
Lower also performed the first blood transfusion from human to human
Anton van Leeuwenhoek:
Dutchman. Invented the microscope and went on to discover red blood cells, bacteria and protozoa
Marcello Malpighi:
Italian. Used the microscope to study the structure of the liver, spleen, lungs, skin, glands and brain
Thomas Willis:
Englishmen. Discovered the presence of sugar in the urine of diabetics and was a pioneer in research into the anatomy of the brain, nervous system and muscles. He coined the term ‘neurology’ and documented the anatomy of the brain and nerves in minute detail
He was the first to number the cranial nerves in order in which they are now usually enumerated by anatomists
What were some medical advancements in the 18th century?
Diagnostic advancements:
Dutch professor Hermann Boerhaave started making systematic use of the thermometer to monitor body temperature
Austrian physician Leopold Auenbrugger discovered the need to tap on the chest to look for fluid in the lungs
Therapeutic advancements:
English surgeon James Lind proved that scurvy (vitamin C deficiency disease) could be cured by eating citrus fruit
Botanist William Withering showed the effectiveness of digitalis in treating heart diseases
Edward Jenner developed the smallpox vaccine, eradicating smallpox, developed from liquid taken from cow pox lesions
Specialisation:
French physician Pierre Fauchard started dentistry science in the early 1700s
Veterinary medicine was properly separated from human Medicine in 1761 when French veterinarian Claude Bourgelat founded the world’s first veterinary school in Lyon
What were some medical advancements in the 19th century?
Cell theory:
A major improvement to the workings of microscope made it possible to study tissues and cells in more detail, leading to the new science of cells called cytology.
Cell theory, which states that all living things are made up of cells that are the basic unit of structure and are produced from other cells (cornerstones of modern Medicine)
Using cell theory, German scientist Rudolf Wichrow demonstrate that changes in cells can cause diseases such as cancer
Germ theory:
English physician John Snow traced the source of cholera to water contaminated by sewage. Before, most physicians believed that diseases-causing germs appeared spontaneously, a belief that lasted from Aristotle
Shortly thereafter, French Chemist Louis Pasteur ran a series of experiments which concluded that life could not be spontaneously generated. Pasteur demonstrated that there were in fact organisms everywhere in the air (through experiment which turned milk sour) and went on to develop a process that heats milk to kill microbes (pasteurisation). His further work also led him to develop vaccines against anthrax and rabies
Germ theory was firmly implanted within Medicine by German physician Robert Koch who identified the specific bacteria that caused anthrax, tuberculosis and cholera. This was the beginning of bacteriology or microbiology
Anaesthesia:
Back in the 16th century, Swiss physician Paracelsus made chickens breathe sweet vitriol and noted that they not only fell asleep but also felt no pain
Later in 1730, German chemist Frobenius gave the liquid the name of ether but it would not be used as an anaesthetic until 1842, being used commonly from 1846 onwards. Drawbacks with ether such as excessive vomiting and its flammability led to its replacement in England by chloroform
Discovered in 1831, the use of chloroform as an anaesthetic is linked to James Young Simpson, who found chloroform’s efficacy in 1847, being used by John Snow in 1853 on Queen Victoria. Unfortunately, chloroform was not as safe as ether, especially when administered by untrained practitioners, pressured by the public leading to many deaths that would’ve been preventable
Antiseptics:
Hungarian physician Ignaz Semmelweiss discovered that infections in obstetrics units following childbirth were most likely due to poor hand-washing by physicians
In the late 1860s British surgeon Joseph Lister helped reduce the rate of death from gangrene by dipping bandages and ligatures into carbolic acid and pouring the acid into the wounds to sterilise them. Marking the start of antiseptic surgery
What were some medical advancements in the 20th century?
Pharmacology:
Felix Hoffmann isolated aspirin (synthesised version of acetylsalicylic acid) in 1897
In 1909 German Scientist Paul Ehrlich synthesised the arsenic-based compound Salvarsan, the first effective treatment for syphilis, thus creating the first antibiotic
In 1928 Sir Alexander Fleming discovered penicillin, effective against anthrax, tetanus, syphilis and pneumonia, widely available after 1944
In 1943 an American biochemist isolated streptomycin, proved effective against tuberculosis
Vaccines against tetanus (1925), influenza (1933), smallpox and polio (1950s), measles (1963), chickenpox (1995), HPV (2006)
Cortisone, a steroid hormone to reduce inflammation and supress the immune system response (1950s)
The contraceptive pill (1960s)
First antiviral drug, acyclovir (1970) against herpes. 1980 saw the development of antiretroviral drugs to combat AIDS
Technology:
In 1895, German physicist Wilhelm Conrad Rontgen discovered X-rays
In 1901, Dutch physiologist Willem Einthroven invented the first electrocariograph
Non-intrusive observation inventions included:
- Ultrasound imaging (1949)
- Computerised tomography, CT (1970s)
- Positron-emission tomography, PET (1975)
- Magnetic resonance imaging, MRI (1970s)
Heart-lung machine was developed providing artificial means to keep patients alive during heart stopping surgery. This cardiopulmonary bypass made major heart surgery more routine.
1970s saw the invention of flexible endoscopes allowing the introduction of laparoscopic surgery (keyhole)
The first artificial kidney was invented in 1913
Artificial hearts were first implanted in 1982
Discovery of plastic in mid-20th century and carbon fibre led to advancements in prosthetics
Computers have made a huge contribution in scanning technology, running machines in surgical theatres, ICUs, handling medical records and prescriptions electronically, research data analysis and mapping the human genome with vast computational powers
Immune system understands:
In 1880s, the Russian biologist Elie Metchnikoff discovered phagocytosis after experimenting on the larvae of starfish. He realised that the process of digestion in microorganisms was essentially the same as that carried out by white blood cells. His theory, that certain WBC could engulf and destroy harmful bodies such as bacteria, met with scepticism from leading specialists including Pasteur
At the time most bacteriologists believed that white blood cells ingested pathogens and then spread them further through the body.
Less than 2 decades later, Paul Ehrlich argued that the chief agents of immunity were antibodies. Both theories turned out to be correct
Classification of autoimmune diseases, Type-1 diabetes, lupus and rheumatoid arthritis, as well as a range of immunosuppressants
These immunosuppressant also play a vital role in ensuring that transplant patients are able to retain the organs that were transplanted thus making organ transplantation an almost routine procedure
Immune therapy also offers hope in the fight against some cancers (Graft vs Tumour effect in HSCT)
Studies against HIV and AIDS developing vaccines and treatments
Genetics:
Vast majority of the progress made in immunological and viral studies is due to a new understanding of genetics
Through DNA had been isolated by Swiss physician Friedrich Miescher in 1869, its structure was decoded in 1953 by British bio-chemist Francis Crick and American biologist James Watson. Knowledge of DNA structure made it possible to determine the location of each gene. By the early 21st century, scientists had mapped the genetic structure of humans, human genome
Cracking the genetic code also enabled the introduction of testing for diseases caused by defective chromosomes such as cystic fibrosis, Huntington’s disease and some forms of breast cancer. It also enabled the creation of new drugs derived from natural body chemicals such as insulin and HGH
From a genetic perspective, the greatest avenue of research is gene therapy, which would enable the curing of diseases by inserting normal copies of abnormal genes directly into cells by means of a virus - via CRISPR-Cas9
