- Natural drugs like alcohol, opium and mandrake had long been used to reduce pain - but effective anaesthetics that didn't make the patient very ill were more difficult to produce.
- Nitrous oxide/laughing gas was identified as a possible anaesthetic by Humphrey Davy in 1799 - but he was ignored by surgeons at the time.
- The gas had been relegated to use as a fairground novelty before Horace Wells suggested its use in dentistry. He did a public demonstration in 1845 but picked a patient unaffected by nitrous oxide so it was ignored again.
- In 1842, Crawford Long discovered the anaesthetic qualities of ether but he didn't publish work.
- The first public demonstration of ether as an anaesthetic was carried out in 1846 by William Morton.
- Ether is an irritant and is also fairly explosive, so using it in this way was risky. In 1847 James Simpson experimented on himself to find an alternative. He discovered the effects of chloroform.
- Chloroform was widely used in operating theatres and to reduce pain during childbirth but it sometimes affected the heart, causing some patients to suddenly die.
- General anaesthesia (complete unconsciousness) is risky so local anaesthesia (numbing of the part being treated) is better for many operations. In 1884, William Halsted investigated the use of cocaine as a local anaesthetic but unfortunately his self-experimentation led to a severe cocaine addiction.
- Some people were suspicious of doctors using anaesthetics - or even objected on religious grounds. Others were afraid of side effects and the dangers of overdose.
- Surgeons were keen to perform more and more complicated operations because an unconscious patient was cooperative and the surgeon could take longer over his work.
- As the dangers of bleeding and infection had not been overcome, the attempts at more complicated surgery actually led to increased death rates amongst patients. The period between 1846 and 1870 is sometimes called the 'Black Period' of surgery.
- Modern anaesthetists use complicated mixtures to produce muscle relaxation or paralysis as well as unconsciousness.
There are two main approaches to reducing infection during an operation: Antiseptic methods are used to kill germs that get near surgical wounds. Aseptic surgical methods aim to stop any germs getting near the wound.
- Ignaz Semmelweis (1818-1865) had used chloride of lime solution as a handwash for doctors to control the spead of puerperal fever, an infection suffered by many woman following childbirth. However, it was very unpleasant so it wasn't very widely used.
- Joseph Lister had seen carbolic acid sprays used in sewage works to keep down the smell. He tried this in the operating theatre in the early 1860s and saw reduced infection rates. Having heard about the germ theory in 1865, he realised that germs could be in the air and on surgical instruments and people's hands. He started using carbolic acid on instruments and bandages. This produced further improvements.
- Carbolic acid is unpleasant to get on your skin or breathe in so many doctors and nurses didn't like or use it.
- The use of antiseptic conditions reduced death rates from as high as 50% to about 15%. By 1890 antiseptics were being used by most European and American surgeons.
By going from killing germs to making a germ-free (aseptic) environment, surgeons have been able to avoid using large amounts of antiseptic in the theatre.
The Aseptic Operating Theatre:
- Instruments are carefully sterilised before use, usually with high temperature steam (120C)
- Theatre staff sterilise their hands before entering and wear sterile gowns, masks, gloves and hats. Surgical gloves were invented by William Halsted in 1889.
- The theatres themselves are kept scrupulously clean and fed with sterile air. Special tents can be placed around the operating table to maintain an area of even stricter hygiene in high risk cases.
- Blood circulates rapidly so it doesn't take long to bleed to death if a major blood vessel is cut. Surgery often causes heavy bleeding.
- The concept of blood transfusions was known from at least the 17th century, when Jean-Baptiste Denys carried out a cross-species transfusion to a human in 1667.
- The problem was that sometimes it worked and sometimes the blood of the recipient clogged - they died and no one ever knew why.
- In 1900, Karl Landsteiner discovered blood groups and the importance of compatibility. He found that certain groups of blood couldn't be mixed together as they would clog the blood vessels.
- During the First World War sodium citrate was found to stop clotting when blood came into contact with the air. This allowed blood to be stored more easily.
- In 1946 the British National Blood Transfusion Service was established.
X-rays and Radiography
- X-rays were discovered by Wilhelm Roentgen in 1895. They pass easily through soft flesh but less well through bone. They also affect photographic film.
- These factors allow simple x-ray images to be produced by directing x-rays at a body part in front of a photographic plate.
- In computerised axial tomography (CAT), a scanner rotates 180 degrees around the body, aiming thin beams of x-rays at receptors on the opposite side of the person. A computer analyses the results and produces an image of the slice of the body. The slices can be built up into a 3D image of the body.
- Between 1896 and 1898 Antoine Hneri Becqueral and Pierre and Marie Curie discovered the first radioactive isotopes. Radioactive isotopes are used to treat cancers as part of radiotheraphy, in immunosuppression and as tracers in diagnosis - mildly radioactive material is swallowed or injected and medics can detect its movement around the body.
- Keyhole surgery is a technique (developed in the 1980s) which makes surgery less invasive. It's popular with patients because scars are smaller and recovery is quicker.
- In keyhole surgery, a surgical instrument called an endoscope is put through a small cut. It gives out light and feeds back a picture to a screen, letting the surgeon see inside the body.
- Other instruments are needed for the actual surgery, which are introduced through even smaller cuts in the skin. Keyhole surgery is usually performed under a general anaesthetic.
- This technique is useful for investigating the causes of pain or infertility. It's also used for vasectomies, removing cysts or the appendix, mending hernias and other minor operations.
- Governments often play key roles in discoveries such as supplying money to fund the research and government spending is often heavily influenced by social attitudes.
Replacing worn out body parts is something we're still just beginning to get the hang of. Mechanical parts are quite common now for joint replacement and prosthetic limbs, but artificial vital organs cannot compare to the real thing. Transplant surgery using donor organs is usually the only option.
- The first organ to be transplanted was the kidney (in 1951), closely followed by the cornea.
- Livers, lungs, pancreases and bone marrow are also transplanted, but the organ that has excited most interest has always beeen the heart. Apart from problems with rejection (which you get with all transplants), with heart transplants you also have to keep the body supplied with blood and oxygen and get the new heart to beat after the operation. In many patients, you also have to deal with additonal problems in other parts of the cardiovascular system.
- The first heart transplant was carried out by Christiaan Barnard on the 3rd December 1967 but the patient only survived for 18 days.
- The poor life expectancy of patients soon led to a temporary stopping of heart transplants.
- The major problem for any transplant is rejection, which is when the host body's immune system attacks the implant. The immune system has to be suppressed until the implant is accepted by the body.
Transplants and Plastic Surgery
- At first corticosteroids were used as immunosuppressants but they often stopped all resistance to diseases like pneumonia (Christiaan Barnard's first patient died of pneumonia).
- Cyclosporin was approved for use in 1983 - a fungus-derived drug which has since been used successfully with many patients. A fungus was also the source of tacrolimus (FK506), another immunosuppressant drug approved for use in 1994.
- Skin grafting had been known in Renaissance Europe and since ancient times in India - but infection had limited its usefulness.
- Harold Gillies began working with burns victims from the First World War.
- His work was continues during the Second World War by his assistant, Archibald McIndoe - probably the most famous plastic surgeon ever. A lot of McIndoe's patients were pilots who had been trapped inside burning aircraft.
- McIndoe's unit in East Grinstead took advantage of new developments in antibacterial drugs and surgical techniques. The staff there also worked very hard to help their patients through the psychological effects of their injuries.