Main organs Heart Main article: Heart transplantation (Diagram illustrating the placement of a donor heart in an orthotopic procedure. Notice how the back of the patient's left atrium and great vessels are left in place). Heart transplantation is performed on patients with end-stage heart failure or severe coronary artery disease. The most common procedure is to take a working heart from a recently deceased organ donor (allograft) and implant it into the patient. The patient's own heart may either be removed (orthotopic procedure) or zapatillas asics baratas , less commonly, left in to support the donor heart (heterotopic procedure). It is also possible to take a heart from another species (xenograft), or implant a man-made artificial one, although the outcome of these two procedures has been less successful in comparison to the far more commonly performed allografts. Lung Main article: Lung transplantation While lung transplants carry certain associated risks, they can also extend life expectancy and enhance the quality of life for end-stage pulmonary patients. While the precise details of surgery will depend on the exact type of transplant, there are many steps which are common to all of these procedures. Prior to operating on the recipient, the transplant surgeon inspects the donor lung(s) for signs of damage or disease. If the lung or lungs are approved , then the recipient is connected to an IV line and various monitoring equipment, including pulse oximetry. The patient will be given general anesthesia, and a machine will breathe for him or her. It takes about one hour for the pre-operative preparation of the patient. A single lung transplant takes about four to eight hours, while a double lung transplant takes about six to twelve hours to complete. A history of prior chest surgery may complicate the procedure and require additional time. Heart-lung Main article: Heart-lung transplant A heart-lung transplant is a procedure carried out to replace both heart and lungs in a single operation. Due to a shortage of suitable donors, it is a rare procedure; only about a hundred such transplants are performed each year in the USA. The patient is anesthetised. When the donor organs arrive, they are checked for fitness; if any organs show signs of damage, they are discarded and the operation cancelled. Some patients are concerned that their organs will be removed and the donor organs won't be suitable. Since this is a possibility [url=http://www.asicszapatillas.es/adidas-boost-baratas.html]comprar adidas boost baratas , it is standard procedure that the patient is not operated on until the donor organs arrive and are judged suitable, despite the time delay this involves. Once suitable donor organs are present, the surgeon makes an incision starting above and finishing below the sternum, cutting all the way to the bone. The skin edges are retracted to expose the sternum. Using a bone saw, the sternum is cut down the middle. Rib spreaders are inserted in the cut, and spread the ribs to give access to the heart and lungs of the patient. The patient is connected to a heart-lung machine, which circulates and oxygenates blood. The surgeon removes the failing heart and lungs. Most surgeons endeavour to cut blood vessels as close as possible to the heart to leave room for trimming adidas stan smith baratas , especially if the donor heart is of a different size than the original organ. The donor heart and lungs are positioned and sewn into place. As the donor organs warm up to body temperature, the lungs begin to inflate. The heart may fibrillate at first - this occurs because the cardiac muscle fibres are not contracting synchronously. Internal paddles can be used to apply a small electric shock to the heart to restore proper rhythm. Once the donor organs are functioning normally, the heart-lung machine is withdrawn, and the chest is closed. Kidney Main article: Kidney transplantation The donor kidney is typically placed inferior of the normal anatomical location. Kidney transplantation is the organ transplant of a kidney in a patient with end-stage renal disease. Kidney transplantation is typically classified as deceased-donor (formerly known as cadaveric) or living-donor transplantation depending on the source of the recipient organ. Living-donor renal transplants are further characterized as genetically related (living-related) or non-related (living-unrelated) transplants, depending on whether a biological relationship exists between the donor and recipient. Liver Main article: Liver transplantation Liver transplantation is the replacement of a diseased liver with a healthy liver allograft. The most commonly used technique is orthotopic transplantation, in which the native liver is removed and the donor organ is placed in the same anatomic location as the original liver. Liver transplantation nowadays is a well accepted treatment option for end-stage liver disease and acute liver failure. Pancreas Main article: Pancreas transplantation A pancreas transplant involves implanting a healthy pancreas (one that can produce insulin) into a person who has diabetes. Because the pancreas performs functions necessary in the digestion process, the recipient's native pancreas is left in place adidas superstar 2 mujer baratas , and the donated pancreas attached in a different location. In the event of rejection of the new pancreas, the recipient could not survive without the native pancreas still in place. The healthy pancreas comes from a donor who has just died or it may be a partial pancreas from a living donor. Whole pancreas transplants from living donors are not possible, again because the pancreas is a necessary organ for digestion. At present, pancreas transplants are usually performed in persons with insulin-dependent diabetes who have severe complications. Face Main article: Face transplant A face transplant is a still-experimental procedure. In addition to skin, the transplant optimally includes bones, along with muscle, skin [url=http://www.asicszapatillas.es/adidas-originals-superstar/adidas-superstar-8... superstar 80s mujer[/url] , blood vessels and nerves. Main tissues and cells Cornea Main article: Corneal transplantation Cornea trans.