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Transplant surgery Procedure
Transplant surgery Procedure is the surgical removal of an organ(s), tissue, or blood products from a donor and surgically placing or infusing them into a recipient.
Purpose
Transplant surgery is a treatment option for diseases or conditions that have not improved with other medical treatments and have led to organ failure or injury. Transplant surgery is generally reserved for people with end-stage disease who have no other options.
The decision to perform transplant surgery is based on the patient's age, general physical condition, diagnosis and stage of the disease. Transplant surgery is not recommended for patients who have liver, lung, or kidney problems; poor leg circulation; cancer; or chronic infections.
Demographics
The typical cut-off age for a transplant recipient ranges from 40-55 years; however, a person's general health is usually a more important factor. In addition, the percentage of transplant recipients over age 50 has increased since 1996.
On average, 66 people receive transplants every day from either a living or deceased donor. In 2002, about 24,500 transplants were performed in the United States:
- 14,400 kidney transplants
- 5300 liver transplants
- 2200 heart transplants
- 1000 lung transplants
- 900 kidney/pancreas transplants
- 550 pancreas transplants
- 104 intestine transplants
- 31 heart/lung transplants
The national waiting list for most transplanted organs continues to grow every year, even though the number of recipients waiting for a heart transplant has leveled off in recent years, and the waiting list for heart-lung transplants has decreased over the past few years. As of April 2003, there were about 81,000 eligible recipients waiting for an organ transplant in the United States.
Transplant procedures
ORGAN HARVESTING. Harvesting refers to the process of removing cells or tissues from the donor and preserving them until they are transplanted. If the donor is deceased, the organ or tissues are harvested in a sterile operating room. They are packed carefully for transportation and delivered to the recipient via ambulance, helicopter or airplane. Organs from deceased donors should be transplanted within a few hours of harvesting. After the recipient is notified that an organ has become available, he or she should not eat or drink anything.
When the organ is harvested from a living donor, the recipient's transplant surgery follows immediately after the donor's surgery. The recipient and the donor should not eat or drink anything after midnight the evening before the scheduled operation.
PREOPERATIVE PROCEDURES. After arriving at the hospital, the recipient will have a complete physical and such other tests as a chest x ray, blood tests, and an electrocardiogram (EKG) to evaluate his or her fitness for surgery. If the recipient has an infection or major medical problem, or if the donor organ is found to be unacceptable, the operation will be canceled.
The recipient will be prepared for surgery by having the incision site shaved and cleansed. An intravenous tube (IV) will be placed in the arm to deliver medications and fluids, and a sedative will be given to help the patient relax.
TRANSPLANT SURGERY. After the patient has been brought to the operating room, the anesthesiologist will administer a general anesthetic. A central venous catheter may be placed in a vein in the patient's arm or groin. A breathing tube will be placed in the patient's throat. The breathing tube is attached to a mechanical ventilator that expands the lungs during surgery.
The patient will then be connected to a heart-lung bypass machine, also called a cardiopulmonary bypass pump, which takes over for the heart and lungs during the surgery. The heart-lung machine removes carbon dioxide from the blood and replaces it with oxygen. A tube is inserted into the patient's aorta to carry the oxygenated blood from the bypass machine back to the heart for circulation to the body. A nasogastric tube is placed to drain stomach secretions, and a urinary catheter is inserted to drain urine during the surgery.
The surgeon carefully removes the diseased organ and replaces it with the donor organ. The blood vessels of the donated organ are connected to the patient's blood vessels, allowing blood to flow through the new organ.
Diagnosis/Preparation
Pre-transplant evaluationSeveral tests are performed before the transplant surgery to make sure that the patient is eligible to receive the organ and to identify and treat any problems ahead of time. The more common pre-transplant tests include:
- tissue typing
- blood tests
- chest x ray
- pulmonary function tests
- computed tomography (CT) scan
- heart function tests (electrocardiogram, echocardiogram, and cardiac catheterization)
- sigmoidoscopy
- bone densitometry test
The pre-transplant evaluation usually includes a dietary and social work assessment. In addition, the patient must undergo a complete dental examination to reduce the risk of infection from bacteria in the mouth.
Blood donation and conservation
Some transplant centers allow patients to donate their own blood before surgery, which is known as autologous donation. Autologous blood is the safest blood for transfusion, since there is no risk of disease transmission. Preoperative donation is an option for patients receiving an organ from a living donor, since the surgery can be scheduled in advance. In autologous donation, the patient donates blood once a week for one to three weeks before surgery. The blood is separated and the blood components needed are reinfused during the operation.
In addition to preoperative donation, there are several techniques for minimizing the patient's blood loss during surgery:
- Intraoperative blood collection: the blood lost during surgery is processed, and the red blood cells are reinfused during or immediately after surgery.
- Immediate preoperative hemodilution: the patient donates blood immediately before surgery to decrease the loss of red blood cells during the operation. The patient is then given fluids to restore the volume of the blood.
- Postoperative blood collection: blood lost from the incision following surgery is collected and reinfused after the surgical site has been closed.
Risks
Short-term risks following an organ transplant include pneumonia and other infectious diseases; excessive bleeding; and liver disorders caused by blocked blood vessels. In addition, the new organ may be rejected, which means that the patient's immune system is attacking the new organ. Characteristic signs of rejection include fever, rash, diarrhea, liver problems, and a compromised immune system. Transplant recipients are given immunosuppressive medications to minimize the risk of rejection. In most cases, the patient will take these medications for the rest of his or her life.
Long-term risks include an elevated risk of cancer, particularly skin cancer. An estimated 6–8% of transplant patients develop cancer over their lifetime as compared to less than 1% in the general population.
Normal results
In a successful organ transplant, the patient returns to a more nearly normal lifestyle with increased strength and stamina.
Morbidity and mortality rates
Mortality figures for transplant surgery include recipients who die before a match with a suitable donor can be found. About 17 patients die every day in the United States waiting for a transplant. In 2001, over 6000 patients died because the organ they needed was not donated in time.
The Scientific Registry of Transplant Recipients gives the first-year survival rates for transplant surgery as follows:
- 97% of pancreas transplant recipients
- 95% of kidney transplant and kidney/pancreas recipients
- 90% of autologous bone marrow transplant patients
- 86% of liver transplant patients
- 85% of heart transplant patients
- 77% of lung transplant patients
- 70% of allogeneic bone marrow transplant patients Three-year survival rates are as follows:
- about 91% for kidney transplant patients
- about 87% for pancreas and kidney/pancreas transplant patients
- about 80% for liver transplant patients
- about 79% for heart transplant patients
- about 59% for lung transplant patients
Category of Transplant Surgery Procedure
Heart transplant
Heart transplant: A surgical procedure in which a diseased heart is replaced with a healthy heart from a deceased person. The world's first heart transplant was done on December 3, 1967 by South African surgeon Christiaan Bernard (1922-2001). The recipient was Louis Washkansky, a grocer. The surgery went well. However, Mr. Washkansky was left vulnerable to infection from the large doses of immune-suppressing drugs (azathioprine and hydrocortisone) and radiation he received. He died of pneumonia 18 days after surgery. The second human heart transplant was also done by Dr. Barnard. On Jan. 2, 1968, Dr. Barnard transplanted the heart of a young man into a retired dentist, Philip Blaiberg. (The young man was of "mixed race" while Dr. Blaiberg was white. The fact that Dr. Bernard ignored racial barriers caused a sensation in apartheid South Africa.) The amount of antirejection drugs was reduced and Dr. Blaiberg survived for 19 months and 15 days. He died of chronic organ rejection. Heart transplant surgery has now become a standard procedure. It had been done about 100,000 times as of 2001 and was carried out on about 2,100 patients in 160 hospitals in the U.S. in 2001, with a one-year success rate of 85-90% and a five-year success rate of 75%. There have been two main barriers to successful heart transplants. The first barrier has been rejection of the donor heart by the patient, as occurred in the case of Dr. Blaiberg. Cyclosporine, which was introduced in 1983, and other medications to control rejection have greatly improved the survival of transplant patients. The second barrier to increasing the number of successful transplantations continues to be the availability of donor hearts.
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