Antisepsis (from the Greek, anti, meaning "against," and sepsis, meaning "decay") is the destruction or control of the growth of microorganisms on living tissue. Antiseptics are the substances that carry out antisepsis. They are applied externally to prevent bacterial growth, to treat skin infections, and to disinfect wounds.
From the earliest times, physicians and healers were aware that certain substances appeared to stop infection and prevent spoilage. Egyptians used resins (natural organic substances), naphtha (flammable liquid hydrocarbon mixtures), and liquid pitch (tar) to decrease decay when preparing their dead for burial. The ancient Greeks and Romans recognized the antiseptic properties of wine, oil, and vinegar. Balsam was used in Europe from the Middle Ages (400–1450) times through the 1800s. Chloride of mercury was introduced as an antiseptic in 1766, and iodine became popular as an antiseptic treatment for wounds after its discovery in 1811.
None of these antiseptics could prevent the almost inevitable infection of wounds, particularly following surgery. Amputations, common in the 1800s, resulted in a high death rate due to infection. The introduction of anesthesia in 1846 added to the problem; it permitted longer and more complex operations, greatly increasing the likelihood of infection following surgery.
Another deadly form of infection was so-called childbed fever, a bacterial infection of the uterus that struck women who had just given birth. Epidemics of childbed fever raced through hospital maternity wards, killing many new mothers. With no knowledge of the existence of bacteria, physicians had no concern for cleanliness. They wore street clothes or filthy operating gowns, used unclean instruments, and often failed to wash their hands properly before examining or operating on patients.
Some of the early advances in antisepsis came about because of attempts to understand and stop childbed fever. Toward the end of the eighteenth century, some doctors began to realize that lack of cleanliness might be related to the spread of infection. When doctors began washing their clothes and hands before examining patients, death rates from infection began to drop dramatically.
Antiseptic: A substance that prevents or stops the growth of microorganisms.
Carbolic acid: An acidic compound that, when diluted with water, is used as an antiseptic and disinfectant.
Childbed fever: A bacterial infection occurring in women following childbirth, causing fever and in some cases blood poisoning and possible death.
Infection: Invasion and multiplication of microorganisms in body tissues.
Sterilization: The process of making a substance free from microorganisms.
French chemist Louis Pasteur (1822–1895) helped to shed light on the source of infection by proving the existence of airborne microorganisms in the 1850s. English surgeon Joseph Lister (1827–1912) applied this new knowledge of bacteria to develop a successful system of antiseptic surgery. Concluding that microorganisms in the air caused the infection of wounds, Lister developed an antiseptic system using carbolic acid. Wounds and surrounding areas were sprayed with the acid to destroy infectious organisms. Multiple layers of dressing were then applied to wounds to protect them from new invasion by bacteria. Lister's method of antisepsis proved to be effective and was eventually adopted by physicians worldwide.
Improvements on Lister's techniques soon developed. The carbolic spray was abandoned in the 1880s in favor of cleanliness, sterilization, and topical antiseptics (antiseptics applied directly to a surface). A final obstacle to surgical antisepsis—germs on the human hands—was overcome by the introduction of rubber gloves. Today, sterile gloves are a requirement for surgical procedures.
Modern methods of preventing infection are very different from the techniques pioneered by Lister and others. Antibiotics, penicillin, and sulfa drugs fight infection inside the body, and aseptic (free from harmful microorganisms) methods such as sterilization prevent bacteria from existing in a given area. However, external antiseptics continue to be important.
Some commonly used antiseptics are hydrogen peroxide, alcohol, boric acid, iodine, formaldehyde, and hexachlorophene. Heat is also an extremely effective antiseptic and, at appropriate temperatures, can be used to disinfect many materials.