Surgery.

Surgery. I INTRODUCTION Surgery, branch of medicine concerned with treatment of diseases, deformities, and injuries through manual procedures called operations. Surgery can be used to repair broken bones, stop uncontrolled bleeding, remove injured or diseased tissue and organs, and reattach severed limbs. Exploratory surgery helps physicians diagnose conditions that cannot be detected by traditional tests. It allows for examination of internal organs for signs of disease. People have practiced surgery since ancient times, but it did not become a respected science until the 19th century. Increasing knowledge of the human body, the discovery of anesthesia (a loss of physical sensation that can be induced with drugs), and the use of germ-free, or sterile, operating procedures combined to make surgery a safe and effective method of medical treatment. In the 20th century advances in technology helped the field of surgery grow at a rapid pace. II SURGICAL DIVISIONS Surgery is performed by specially trained medical physicians known as surgeons. General surgery training and training in some surgical specialties, such as neurosurgery, which concerns the brain, spinal cord, and peripheral nerves, and orthopedic surgery, which repairs the bones and joints, is conducted in association with a hospital and usually lasts from five to seven years. At the end of this period, known as a residency, the general surgeon may receive further training to learn the skills of a particular specialty, or subdivision, of surgery. Surgical subdivisions include, for example, thoracic surgery, which is concerned with diseases of the chest; vascular surgery, which corrects diseases of blood vessels; plastic surgery, which reconstructs or cosmetically improves features of the body; and pediatric surgery, which is concerned with operations on children. General surgery is the broadest surgical division, focusing on surgery of the abdomen, the breast, and the endocrine organs--the glands and tissues of the body that secrete hormones for controlling growth, development, and other bodily functions. General surgeons operate on the appendix, colon, small intestine, gallbladder, stomach, pancreas, spleen, and liver. Pediatric surgery is a subdivision of general surgery that focuses on the unique conditions of operating on infants and children--their organ systems are not fully developed, and anesthetics and medications must be adjusted for their smaller bodies. The most common pediatric procedures include correction of birth defects and removal of abnormal growths that are potentially cancerous. Colon and rectal surgery procedures are performed on the anus, rectum, and intestines. These include operations to treat hemorrhoids (enlarged veins around the anus), polyps (usually benign growths), and cancer. In a colostomy, surgeons remove all or part of the large intestine. An opening called a stoma is then made in the abdomen, which allows the colon to empty waste into a specially designed plastic bag located outside of the body. An ileostomy is a similar operation in which the lower part of the small intestine is routed to the stoma. Neurological surgery involves operations on the brain and spinal column. These procedures include excising, or cutting out, brain tumors and removing ruptured discs in the spine, an operation known as a laminectomy. The use of specialized imaging equipment, such as computed tomography (CT) and magnetic resonance imaging (MRI), permits surgeons to identify the exact location of some tumors, making surgery to remove these growths more precise and less harmful to surrounding healthy tissue. Gynecology encompasses a variety of procedures, including surgery to remove diseased reproductive organs such as the uterus (see Hysterectomy); surgery to remove tumors of the breast; and procedures to correct female infertility or facilitate permanent contraception (see Tubal Sterilization). Obstetrics is a division that focuses on all aspects of a woman's pregnancy and may involve procedures such as a cesarean section, the surgical delivery of a newborn infant, or an episiotomy, a surgical enlargement of the vaginal opening. Ophthalmic surgery involves operations on the eye and often requires the use of microsurgical techniques performed under a microscope. Such procedures include the removal of a cataract (a clouding of the lens of the eye) and implantation of an artificial lens to restore vision; reconnection of a detached retina to the back of the eyeball; and radial keratotomy (RK), an operation on the cornea to correct nearsightedness. Orthopedic surgery entails operations on bones, muscles, and joints. Orthopedic surgery allows for the replacement of hip and knee joints with artificial joints made of special metals and plastics. Fractures in bones are repaired with the implantation of pins, metal plates, and screws. These techniques greatly reduce the time needed for healing and recuperation. A subdivision of orthopedic surgery is sports medicine, which treats injuries and coordinates physical rehabilitation of amateur and professional athletes. Otolaryngology involves the medical and surgical treatment of diseases of the ears, nose, tongue, larynx (vocal cords), and neck, which includes the esophagus, trachea, and blood vessels. Treated diseases include cancers of the head and neck. Radiation therapy and chemotherapy regimens have reduced the need for radical operative removal of these cancers. Significant advances have also been made in restoring the ability to swallow and speak following operations of the neck. Plastic surgery encompasses cosmetic procedures to improve appearance and reconstruct damaged parts of the body such as skin and underlying muscle. Cosmetic procedures include enlarging or reducing the size of the breasts; rhinoplasty (cosmetic surgery on the nose); face lift (cosmetic surgery to tighten facial tissues); and blepharoplasty (cosmetic surgery on the eyelids). Reconstructive procedures include modifying tissues and scars to minimize deformities due to birth defects, prior operations, or traumatic events like car accidents. New developments in three-dimensional computer software imaging help plastic surgeons simulate the results of a particular procedure to show a patient the visual results possible before surgery is performed. Thoracic surgery deals with surgery of the lungs, chest wall, heart, and large blood vessels of the chest. Typical procedures include the removal of malignant cancers and correction of structural birth defects in the lungs and chest. Cardiac surgery is a subdivision of thoracic surgery. Cardiac surgeons perform over 500,000 heart operations annually in the United States. These include coronary artery bypass graft (CABG) surgery, which restores blood flow through vessels blocked by atherosclerosis (a buildup of plaque on the inner walls of the arteries); heart valve replacement surgery, which replaces damaged or worn heart valves with artificial valves; and heart transplants, in which a patient's diseased heart is replaced by the healthy heart of a donor. Vascular surgery involves replacing or repairing blood vessels, particularly arteries that deliver oxygenated blood to the body tissues. Operations on major abdominal arteries that carry blood to the legs or brain are performed to restore blood flow diminished by atherosclerosis. A procedure known as carotid artery endarterectomy--removal of blockages in the carotid artery in the neck--reduces the incidence of stroke in some patients. Weakness in a blood vessel wall can result in the development of an aneurysm, a dangerous widening of the blood vessel. Large aneurysms, which can rupture and cause death, are removed surgically and the blood vessel is reconstructed using a synthetic substitute. Urology deals with kidney disorders, including malignancies, bladder and ureter problems, kidney stones, male infertility and reproductive disorders, and diseases and malignancies of the prostate gland in males. One of the most common operations is transurethral resection of the prostate (TURP), which removes portions of an enlarged prostate. III SURGICAL PROCEDURES Surgical procedures are classified as optional, required, elective, urgent, and emergent based on the patient's medical condition. Optional surgery consists of operations that are not required but which the patient chooses to undergo as with some types of cosmetic surgery. Required surgery is performed when only surgery will correct a problem--such as cataracts--but the surgery can be delayed for a period of weeks or months. Elective surgical procedures usually involve conditions that may not require surgery but in which surgery will have a favorable effect--such as the removal of a small cyst. Urgent surgical procedures are performed when a patient's condition is not immediately life-threatening, but failure to treat it may result in death. Patients with some form of cancer are often considered urgent surgical cases. Emergency procedures must be performed within a few hours of a patient's arrival at a hospital to prevent death. These surgeries correct serious life-threatening conditions such as major wounds, blockages of the intestines, or appendicitis--inflammation of the appendix. For any surgical procedure, medical care is provided before (preoperative), during (intraoperative), and after (postoperative) the operation. Preoperative care includes routine checks of vital signs including temperature, pulse, and blood pressure; analysis of blood and urine; and physical examination to evaluate organ function. An anesthesiologist (a physician trained to provide anesthesia) looks for signs that might make the administration of anesthetics dangerous such as chest infections or low blood pressure. A history of the patient's use of medications is acquired to prevent possible adverse interactions with anesthetics. A surgeon will generally counsel the patient and his or her family about the surgery and what to expect after the operation is performed. Preoperative care reduces the risk of complications during and after surgery. Intraoperative care involves several members of the surgical team. The surgeon determines the timing of the operation, the techniques, and the instruments and supplies to be used. The anesthesiologist controls the patient's pain and, if necessary, the level of unconsciousness to make surgery more tolerable and ensure that the patient regains consciousness safely and quickly following the operation. The scrub nurse readies all instruments, ensures the sterility of the surgical field, and anticipates when instruments will be needed by the surgeon. The circulating nurse makes sure the operating room is adequately supplied and provides any additional supplies to the scrub nurse during the operation. Depending upon the hospital, surgical assistants, physician assistants, surgical residents, medical students, and nursing students may also attend an operation. Postoperative care begins in a recovery room or intensive care unit (ICU). Both areas are equipped to monitor blood pressure and heart rate and provide supplemental oxygen, mechanical ventilation for the lungs, and physical support under critical circumstances. Drugs are often prescribed to control postoperative pain. IV HISTORY OF SURGERY The first surgical procedures were performed in the Neolithic Age (about 10,000 to 6000 pressure on the brain, may have been performed as early as 8000 BC. BC). Trepanning, a procedure in which a hole is drilled in the skull to relieve In Egypt, carvings dating to 2500 BC describe surgical circumcision--the removal of foreskin from the penis and the clitoris from female genitalia. Operations such as castration (the removal of a male's testicles); lithotomy (the removal of stones from the bladder); and amputation (the surgical removal of a limb or other body part) are also believed to have been performed by the Egyptians. Ancient Egyptian medical texts have been found that provide instructions for many surgical procedures including repairing a broken bone and mending a serious wound. In ancient India, the Hindus surgically treated bone fractures and removed bladder stones, tumors, and infected tonsils. They are also credited with having developed plastic surgery as early as 2000 BC in response to the punishment of cutting off a person's nose or ears for certain criminal offenses. Using skin flaps from the forehead, Hindu surgeons shaped new noses and ears for the punished criminals. In the 4th century BC, the Greek physician Hippocrates published descriptions of various surgical procedures, such as the treatment of fractures and skull injuries, with directions for the proper placement of the surgeon's hands during these operations. During most of the Middle Ages (5th century to 14th century AD), the practice of surgery declined. It was viewed as inferior to medicine, and its practice was left to barbers who traveled from town to town cutting hair, removing tumors, pulling teeth, stitching wounds, and bloodletting, the practice of draining blood from the body, then thought to cure illness. The red-and-white striped pole that today identifies barbershops derived its design from this practice. The red stripes symbolize blood and the white stripes signify bandages. In 1316 the French surgeon Guy de Chauliac published Chirurgia magna (Great Surgery). This massive text describes how to remove growths, repair hernias (protrusion of an organ through surrounding structures), and treat fractures using slings and weights. The text helped surgery gain respect as a serious science. At this time a new order of surgeons arose in France. They were called surgeons of the long robe, distinguished from the barber surgeons who were known as surgeons of the short robe. The barber surgeons had little medical training, while the surgeons of the long robe were studied physicians and considered such practices as bloodletting primitive. Corporations, or guilds, of surgeons of the long robe were formed in several countries. During the 16th, 17th, and 18th centuries, many discoveries in surgical practice took place. Much credit belongs to the French surgeon Ambroise Paré, often called the father of modern surgery. Paré successfully employed the method of ligating, or tying off, arteries to control bleeding, thus eliminating the old method of cauterizing, or searing, the bleeding part with a red-hot iron or boiling oil. Discoveries about functions of the human body also helped make surgery a more accurate science during this period. For example, the English physician and anatomist William Harvey discovered the process of blood circulation and Italian anatomist Marcello Malpighi identified the existence of tiny blood vessels called capillaries that carry blood from the major blood vessels to the cells of the body. John Hunter, a British anatomist and surgeon, stressed the close relationship between medicine and surgery and performed many experimental operations that advanced the practice of surgery. Most surgery, however, continued to be restricted to less critical areas of the body or to operations that did not penetrate the skin too deeply. Surgeons rarely opened the abdomen, chest, or skull because of the pain it caused the patient and the risk of infection. This changed in 1846 when anesthesia was used as a way to mask pain during surgery by American dentist William Morton. Although Morton is often credited with the discovery of surgical anesthesia, American surgeon Crawford Long used anesthesia in 1842 during the removal of tumors but did not publish his results until 1849. Post-surgical infections remained a serious complication of surgery until the mid-19th century when the French chemist Louis Pasteur discovered that fermentation or putrefaction, the decay and death of body tissue, is caused by bacteria in the air. In 1865 the British surgeon Joseph Lister applied Pasteur's work to surgery, developing antiseptic (germ-killing) techniques including the use of a carbolic acid spray to kill germs in the operating room before surgery. These antiseptic procedures helped eliminate postoperative infection. Other physicians, including Austrian Ignaz Semmelweiss and American Oliver Wendell Holmes, determined that bacteria are also carried on the hands and clothing and transferred from patient to patient as a physician attends one after another. These physicians pioneered techniques such as washing hands and changing into clean clothing before surgery that prevent wounds from being contaminated during surgery. In the late 1800s, having solved the problems of pain and infection, surgeons began performing new types of surgery including procedures on the abdomen, brain, and spinal cord. At the turn of the 20th century, improved diagnostic abilities and methods of treatment helped surgery become even more effective. When the German physicist Wilhelm Conrad Roentgen invented X ray in 1895 to "photograph" the inside of the body he changed the way surgery was performed. The discovery of the blood groups A, B, and O by Austrian pathologist Karl Landsteiner enabled surgeons to give patients transfusions of their own blood type to ensure survival during surgery. The need for a readily available supply of blood for transfusions led to the creation of blood banks in 1937. Other technological advances permitted surgeons to perform increasingly complex and difficult operations. The introduction of antibiotics in the 1940s further minimized the risk of postoperative infection. The development of the heart-lung machine in 1953 by American surgeon John H. Gibbon allowed surgeons to more easily and successfully perform surgery on these organs. It also marked the beginning of modern clinical heart surgery. The operating microscope, developed in the 1950s, provided surgeons with a way to perform delicate operations on minute body structures like the inner ear and the eye, and more recently, enabled surgeons to reattach the tiny blood vessels from severed limbs to the body (see Microsurgery). The first kidney transplants were performed in the 1950s, and the first heart transplant, in 1967, was performed by South African physician Christiaan Barnard (Medical Transplantation). V SURGERY TODAY New techniques continue to advance the field of surgery. High frequency sound waves, called ultrasound, are directed at kidney and gallbladder stones to break them apart so that they can be eliminated through the excretory system. Cryosurgery freezes and destroys abnormal tissue and is used to treat hemorrhoids and some cervical disorders, and to remove certain skin growths. Laser surgery, on the other hand, uses a beam of light to vaporize or destroy tissue, a procedure commonly employed in ophthalmology, neurosurgery, and thoracic surgery. A variety of surgical procedures are performed using an endoscope, an instrument that permits doctors to view the inside of the body without making a large incision and through which special tools such as lasers or knives can be inserted to operate on a particular area of the body. Surgery using an endoscope, also called laparoscopy, is used to perform tubal sterilization, gallbladder removal, or lung removal. This technique is commonly used for biopsies, in which tissue is removed from an organ for evaluation under a microscope, or for removing patches of diseased tissue. Transplantation surgery, in which organs or tissues are removed from one person and surgically implanted into another person, is now performed for the eye lens and cornea, blood, bones and bone marrow, heart, lung, liver, and pancreas. In severe burn cases, healthy skin from an uninjured site is transferred to an area that has been damaged. Patients typically receive transplants when their own organs fail. Donor organs come from recently deceased individuals who have indicated on organ donor cards a desire to donate organs or whose family members have authorized donation of the deceased's organs. Donated organs must be transplanted within 24 to 48 hours after a donor's death. Ambulatory, or same-day surgery, is performed in a physician's office or clinic. It involves operations that use minimally invasive techniques, require less extensive cutting, and use anesthesia that clears rapidly from the body. Some types of plastic surgery, implantation of permanent pacemakers, breast surgery, and biopsies are typically performed in ambulatory surgical clinics. Contributed By: Norman S. Kato Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.