Antisepsis

Resources

Antisepsis is the prevention or inhibition of an infection by either killing the organism responsible for the infection, or weakening the organism so that it is unable to cause the infection or survive. This is usually achieved by application of an antiseptic or germicidal preparation.

An antiseptic differs from an antibiotic. An antibiotic is specifically directed to a target bacterium or different types of bacteria. There are many different classes of antibiotics, some of which can kill only a few types of bacteria; others are effective against many types of bacteria.

An antiseptic is a chemical compound that is “broad spectrum” in its activity; that is, it kills a wide variety of bacteria and other microorganisms. Because many antiseptics are used on the skin (e.g., “swabbing” the skin with iodine before an injection), antiseptics tend to be non-irritating.

The search for antiseptic agents is as old as humanity. In a hieroglyphic prescription dating from c. 1500 BC, an Egyptian is depicted ordering a mixture of grease and honey for treatment of a wound. While infections and their causes were not known at that time, the relief provided by antiseptic compounds was recognized.

Other historical “cures” for infections include plant extracts, broths of animal or plant materials, and poultices of moss, mud, or dung. Not until the eighteenth century did progress begin to be made toward conquering everyday infections.

As late as the beginning of the nineteenth century, physicians had no knowledge of the septic (infectious) process or its prevention. Although surgery had developed steadily, the mortality rate among patients was high; the patient might die from an infected organ or from the surgery to remove it. Surgeons went from one patient to the next without washing their hands or changing aprons. Thus, the bacteria from one patient were readily passed to the next, and sepsis was an accepted fact.

In the middle of the nineteenth century, the Hungarian obstetrician Ignaz Semmelweiss (1818–1865) proposed that the infectious agent of puerperal fever, which was fatal to many women during childbirth (hence its other name, childbed fever), could be spread by the attending physician. Semmelweiss further suggested that washing hands between patients could prevent the infection. At first he was ridiculed, but when his rate of fatal puerperal fever infections declined rapidly with his practice of washing his hands, other obstetricians soon adopted the practice. This was the first introduction of antisepsis into medical practice.

In the latter half of the nineteenth century, British physician Joseph Lister (1827–1912) introduced the practice of spraying carbolic acid over patients during operations. This reduced the contamination of the open wound from airborne microorganisms and microbes on the doctor’s clothing or gloves. Lister’s innovation brought aseptic technique into the operating theatre.

The early antiseptics were based on mercury (mercurochrome, merthiolate), but have fallen into disuse. Although mercury poses a serious health hazard if absorbed into the body, the small amounts of mercury in the mercury-based antiseptics posed little threat. They were discontinued because they were relatively ineffective. Although mercury-based antiseptics readily

KEY TERMS

Attenuated— A bacterium that has been killed or weakened, often used as the basis of a vaccine against the disease caused by the bacterium.

Etiology— The cause or origin of a disease or condition.

Organic— Carbon-based material. The word organism is derived from organic, meaning any life form.

Pathogenic— Disease causing.

Sepsis— From the Greek, meaning decay; the presence in the blood or other tissue of a microorganism that causes an infection or disease.

stopped bacteria from reproducing and spreading, they did not kill the microorganism. Once the merthiolate was washed away, the bacteria revived and resumed their invasion of the tissues.

Now the innovations of Semmelweiss and Lister are an accepted part of medicine. Modern antisepsis is both preventive and therapeutic. Examples of preventive measures include: hand washing by the surgeon; use of sterile surgical gowns, masks, gloves and equipment; and the preparation of the patient’s skin with antiseptic. Therapeutic antisepsis is the application of a bactericidal agent to an infected area to kill the infectious agent.

Antiseptics have also found their way into the home. Various powders, liquids, or ointments are applied to the surface of the skin to prevent infection of a cut, splinter, or other superficial wound. These antiseptics are for external use only, and each is effective against only one type of bacterium (e.g., gram-positive bacteria).

Newer antiseptics are based on the quaternary ammonium compounds (such as benzalkonium chloride and benzethonium chloride). “Quats” are longstanding and powerful antiseptics. Other common antiseptics include alcohols (e.g., ethyl or isopropyl alcohol), hydrogen peroxide, and phenol. Each is effective against a narrow range of bacterial infections, but none is effective against viruses. These antiseptics often are mixed to provide a wider range of antibacterial activity. They are applied externally on a cut or scrape to prevent infection and, when incorporated into mouthwash, can be gargled to kill bacteria that may cause a sore throat.

As beneficial as their use can be, the overuse of antiseptics is a problem. Microorganisms that are not killed by the application of an antiseptic can develop resistance to the compound. In bacteria such as Escherichia coli the genetic changes that drive this resistance can also bestow resistance to other chemicals, including some antibiotics. The result in the home can be the selection of a hardier variety of E. coli that may be more prone to cause illness.

Resources

BOOKS

Bankston, John. Joseph Lister and the Story of Antiseptics. Hockessin, DE: Mitchell Lane Publishers, 2004.

Drug Facts and Comparisons. 56th ed. New York: Facts and Comparisons, 2002.

Krasner, R.I. The Microbial Challenge: Human-Microbe Interactions. Washington: American Society for Microbiology Press, 2002.

Brian Hoyle

Antisepsis

Antisepsis is the destruction or inhibition of (slowing the growth of) microorganisms (very small living substances invisible without a microscope) that exist on living tissue. Antiseptics are the substances that kill or prevent the growth of the microorganisms. The name comes from the Greek words anti (against) and sepsis (decay). Antiseptics prevent infection and other changes in living tissue by destroying or slowing the growth of germs (microorganisms that cause disease). The nature and use of anti-septics was not fully understood until the discovery of bacteria.

When the skin is broken by a scratch or burn, microorganisms often begin to grow in the wound. Bacteria, viruses, and fungi that may be present on healthy skin can multiply rapidly where the skin is broken. Unless this growth is prevented or stopped, serious infection can take place. Organisms may also enter the body at the site of an injury and cause illness. To prevent this, antiseptics are applied to control the infective growth until the injury heals.

Antiseptic History

Since ancient times, physicians and healers have been aware of the anti-infective and anti-spoilage properties of certain substances. Egyptian embalmers (people who preserved and prepared bodies for burial) used resins (an organic substance taken from plants and trees), naphtha (a liquid hydrocarbon often used as a solvent or diluting agent), and liquid pitch, along with vegetable oils and spices. The effectiveness of this mixture is shown in the fine state of preservation of Egyptian mummies. Persian laws instructed people to store drinking water in bright copper vessels. The ancient Greeks and Romans recognized the antiseptic properties of wine, oil, and vinegar. The use of wine and vinegar in the dressing of wounds dates back to the Greek physician Hippocrates (460-377 b.c.). Balsam, an antiseptic of both southeast Asia and Peru, was introduced to Europe in medieval times and remained in use through the 1800s.

A thirteenth-century surgeon, Theodoric of Bologna, recommended dressings dipped in wine to ward off the development of pus in wounds. English physician Sir John Pringle (1707-1782) published a series of papers entitled Experiments Upon Septic and Antiseptic Substances that contain one of the first uses of the word antiseptic. Genevieve Charlotte d'Arconville introduced the use of chloride of mercury as an antiseptic in 1766. After Bernard Courtois (1777-1838) discovered iodine in 1811, it became a popular antiseptic treatment for wounds.

None of these antiseptics, however, was sufficient to prevent the almost certain infection of wounds, particularly following surgery. Amputations, for example, were common in the 1800s, especially in the case of compound fracture (bone breaks that injure surrounding soft tissue). Amputations had a 40 to 45 percent mortality rate. The introduction of anesthesia in 1846 made the problem worse. It permitted more complicated and lengthy surgical operations, greatly increasing the likelihood of infection.

Puerperal Fever

Another deadly form of infection was puerperal (occurring at the time of childbirth) fever, a streptococcus infection of the uterus that struck women who had just given birth. As more women gave birth at hospitals, epidemics of puerperal fever raced through maternity wards, sharply increasing maternal death rates. Most obstetricians (doctors who treat pregnant women) were baffled by the causes and possible prevention of this fever. The reason for this epidemic of lay in a lack of knowledge about the existence of bacteria until Louis Pasteur's (1822-1895; discovered the connection between bacteria and disease) work. Physicians—surgeons in particular—had no concern for cleanliness. They wore unwashed street clothes or filthy operating gowns, used unclean instruments, and did not wash their hands before examining or operating on patients, even after examining an infected corpse. Many doctors took pride in the accumulation of blood and pus on their medical garments.

Attempts to understand and stop puerperal fever brought about some of the early advances in antisepsis. In 1773 Dr. Charles White (1728-1813) of England recommended antiseptic injection in some cases of childbirth. Scottish physician Alexander Gordon (1752-1799) stated that obstetricians should wash their hands and clothes before treating patients. American physician and author Oliver Wendell Holmes (1809-1894) presented his conclusions about the spread of puerperal fever by unwashed doctors in 1843, while Hungarian doctor Ignaz Semmelweiss made the same discovery in 1847. When Semmelweiss required his students to wash their hands in an antiseptic chloride solution before examining patients, maternal death rates plunged from a high of 18 percent to a low of nearly 1 percent. Semmelweiss was correct about the transmission of infectious materials, but he could not explain what those substances were. Pasteur had part of the answer. In his studies of fermentation (organic transformation), Pasteur proved the existence of airborne microorganisms.

Lister's Work

English surgeon Joseph Lister (1827-1912; professor at London's King's College Hospital) applied this new knowledge of bacteria to develop a successful system of antiseptic surgery. Concerned about the high rate of infection after surgery, Lister studied wound healing with the use of a microscope. After reading Pasteur's work, Lister concluded that microorganisms in the air caused the infection of wounds. Drawing on a report of the effects of carbolic acid on sewage bacteria, Lister developed an antiseptic system using the acid. He sprayed a wound and surrounding areas to destroy infectious organisms and also protected the area from new invasion by bacteria by using multiple-layer dressings. Lister first used the method successfully in an operation on a compound fracture of the leg in 1865.

Lister's antiseptic method was not simple, but it was effective. A published account of his successful application of the technique appeared in The Lancet in 1867 and ignited controversy (especially since Pasteur's germ theory of disease was still in dispute). Nevertheless, Listerian anti-septic surgery gained supporters worldwide, especially in Germany, where the technique was applied somewhat successfully in treating soldiers during the Franco-Prussian War (1870-1871). Doctors in the United States were especially resistant to the practice of antisepsis. Widespread acceptance came in the 1890s after German bacteriologist Heinrich Koch (1843-1910) effectively proved that germs cause disease.

Modern Antisepsis

A final obstacle to surgical antisepsis was the human hands. Although surgical instruments and dressings can be sterilized, surgeons' and nurses' hands can only be washed with antiseptics. An American doctor, William Halsted, solved this problem in 1890. Halsted received his medical degree from Columbia University in 1877. He returned to the United States from two years of study in Europe as a convert to the Listerian method of antisepsis. After breaking an addiction caused by his experiments with cocaine as an anesthetic, Halsted became chief of surgery at Johns Hopkins Medical School. There, he pioneered the use of rubber gloves in surgery to protect his head nurse, Caroline Hampton, from the antiseptic that was irritating her hands. Today sterile gloves are required during all surgical procedures.

Modern methods of preventing infection are very different from the techniques used by Lister and others. Antibiotics, penicillin, and sulfa drugs fight infection internally, and aseptic methods such as sterilization prevent bacteria from existing in a given area. Nevertheless, antiseptics continue to be important and are a lasting monument to Lister's vision. Among the most important used today are iodine, boric acid, and alcohol.

[See also Adhesives and adhesive tape ; Surgical instruments ]

Antisepsis

Antisepsis is the prevention or inhibition of an infection by either killing the organism responsible for the infection, or weakening the organism so that it is unable to cause the infection or survive. This is usually achieved by application of an antiseptic or germicidal preparation.

An antiseptic differs from an antibiotic. An antibiotic is specifically directed to a target bacterium or different types of bacteria . There are many different classes of antibiotics , some of which can kill only a few types of bacteria; others are effective against many types of bacteria.

An antiseptic is a chemical compound that is "broad spectrum" in its activity; that is, it kills a wide variety of bacteria and other microorganisms . Because many antiseptics are used on the skin (e.g., "swabbing" the skin with iodine before an injection), antiseptics tend to be non-irritating.

The search for antiseptics

The search for antiseptic agents is as old as humanity. In a hieroglyphic prescription dating from c. 1500 b.c., an Egyptian is depicted ordering a mixture of grease and honey for treatment of a wound. While infections and their causes were not known at that time, the relief provided by antiseptic compounds was recognized.

Other historical "cures" for infections include plant extracts, broths of animal or plant materials, and poultices of moss , mud, or dung, Not until the eighteenth century did progress begin to be made toward conquering everyday infections.

As late as the beginning of the nineteenth century, physicians had no knowledge of the septic (infectious) process or its prevention. Although surgery had developed steadily, the mortality rate among patients was high. Whether the patient would die from an infected organ or from the surgery to remove it often was a moot point. Surgeons went from one patient to the next without washing their hands or changing aprons. Thus, the bacteria from one patient were readily passed to the next and sepsis was an accepted fact.

In the middle of the nineteenth century, the Hungarian obstetrician Ignaz Semmelweiss (1818–1865) proposed that the infectious agent of puerperal fever, which was fatal to many women during childbirth (hence its other name, childbed fever), could be spread by the attending physician. Semmelweiss further suggested that washing hands between patients could prevent the infection. At first he was ridiculed, but when his rate of fatal puerperal fever infections declined rapidly with his practice of washing his hands, other obstetricians soon adopted the practice. This was the first introduction of antisepsis into medical practice.

In the latter half of the nineteenth century, British physician Joseph Lister (1827–1912) introduced the practice of spraying carbolic acid over patients during operations. This reduced the contamination of the open wound from airborne microorganisms and microbes on the doctor's clothing or gloves. Lister's innovation brought aseptic technique into the operating theatre.

The early antiseptics were based on mercury (mercurochrome, merthiolate), but have fallen into disuse. Although mercury poses a serious health hazard if absorbed into the body, the small amounts of mercury in the mercury-based antiseptics posed little threat. They were discontinued because they were relatively ineffective. Although mercury-based antiseptics readily stopped bacteria from reproducing and spreading, they did not kill the microorganism. Once the merthiolate was washed away, the bacteria revived and resumed their invasion of the tissues.

Modern antisepsis

Now, the innovations of Semmelweiss and Lister are an accepted part of medicine. Modern antisepsis is both preventive and therapeutic. Examples of preventive measures include hand washing by the surgeon, use of sterile surgical gowns, masks, gloves and equipment, and the preparation of the patient's skin with antiseptic. Therapeutic antisepsis is the application of a bactericidal agent to an infected area to kill the infectious agent.

Antiseptics have also found their way into the home. Various powders, liquids, or ointments are applied to the surface of the skin to prevent infection of a cut, splinter, or other superficial wound. These antiseptics are for external use only and each is effective against only one type of bacterium (e.g., gram positive bacteria).

Newer antiseptics are based on the quaternary ammonium compounds (such as benzalkonium chloride and benzethonium chloride). "Quats" are longstanding and powerful antiseptics. Other common antiseptics include alcohols (e.g., ethyl or isopropyl alcohol ), hydrogen peroxide , and phenol. Each is effective against a narrow range of bacterial infections, but none is effective against viruses. These antiseptics often are mixed to provide a wider range of antibacterial activity. They are applied externally on a cut or scrape to prevent infection and, when incorporated into mouthwash, can be gargled to kill bacteria that may cause a sore throat.

Resources

books

Krasner, R.I. The Microbial Challenge: Human-Microbe Interactions. Washington: American Society for Microbiology Press, 2002.

Drug Facts and Comparisons, 56th ed. New York: Facts and Comparisons, 2002.

periodicals

Purdy, C. "It's the Little Things That Count." Current Health 20 (March 1994): 20–22.

Brian Hoyle

KEY TERMS

Attenuated

—A bacterium that has been killed or weakened, often used as the basis of a vaccine against the disease caused by the bacterium.

Etiology

—The cause or origin of a disease or condition.

Organic

—Carbon based material. The word organism is derived from organic, meaning any life form.

Pathogenic

—Disease causing.

Sepsis

—From the Greek, meaning decay, the presence in the blood or other tissue of a microorganism that causes an infection or disease.

an·ti·sep·sis / ˈantiˌsepsis/ • n. the practice of using antiseptics to eliminate the microorganisms that cause disease. Compare with asepsis.

antisepsis (anti-sep-sis) n. the elimination of bacteria, fungi, viruses, and other microorganisms that cause disease by the use of chemical or physical methods.