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the lymphocytotoxicity. 12 The better the histocompatibility match
and degree of genetic similarity between the donor and the recipient,
the less severe is the rejection response. In living related donors, an
identical match is ideal; however, a half match is acceptable. 9 Also, a
white cell crossmateh is performed in which the lymphocytes from the
donor are mixed with the serum from the recipient and then observed
for immune responses. A negative crossmatch indicates no antibody
reaction and that the recipient's antibodies are compatible with the
donor. A negative crossm.tch is required for successful kidney and
kidney-pancreas transplants.7
ORGAN TRANSPLANTATION 701
Although pretransplant tissue typing is ideal, it is not always performed. Somerimes, there is insufficient time to perform HLA ryping between donor and recipient because of the short cold ischemic times
for different organs. '2 Owing to the shorr ischemic time of less than 6
hours for orthotopic cardiac transplants, ABO blood type compatibility, body weight, and accrued waiting time are used for allocation of the donor heart.!·'o A lung transplant recipient is matched on the
basis of ABO blood rype and size, because the ischemic time is less
than 4 hours. s A size match is based on the donor's height, weight,
and thoracic dimensions as determined by chest radiograph.13
In the United States, organ procurement and distribution for transplantation are administered by the United Network for Organ Sharing (UNOS). UNOS sets the standards for ttansplant centers, transplant physicians, tissue ryping laboratories, and organ procurement organizations. UNOS distributes organs based on the severity of the recipient's illness, blood type, donor-recipient weight match, and
length of recipient waiting time. 14
General Post-Transplantation Care and Complications
Postoperative Care for Livittg Dottors
PostOperative care for living donors is similar to that of any patient
who has undergone major abdominal or cardiothoracic surgery.
These patients are taken off mechanical ventilation in the recovery
room and transferred to the general surgery or transplant ward. Vital
signs and blood countS are monitored closely for possible postoperative bleeding. Patients are usually out of bed and ambulating on postoperative day 1 . On average, the duration of donor hospitalization may range from 3 days for a kidney donor to 8 days for a simultaneous pancreas-kidney (SPK) donor. ',1S
Postoperative Care for Tra1lsp[atlt Recipiettts
Once an organ is transplanted, the postOperative care focuses on the
monitoring and treatment of the following" :
• Allograft function
• Rejection
702
AClITE CARE HANDBOOK FOR PHYSICAL THERAPISTS
• Infection
• Adverse effects of immunosuppressive drugs
General postoperative care for rransplant recipients is also similar
to the care patients receive after major abdominal or cardiothoracic
surgery. Except for kidney transplant recipients, who are normally
extubated before leaving the operating room, most patients are transferred from the operating room to the surgical intensive care unit, where they are weaned from mechanical ventilation within 24 to 48
hours.",I6,17 Once extubated and hemodynamically stable, recipients
are transferred to specialized transplant floors. Nursing staff monitors
the recipient closely for signs and symptoms of infection and rejection, which are the leading causes of morbidity and mortality in the first year after transplantation.
Complications from postoperative transplantation may contribute
to an increased length of hospital stay or hospital readmissions. They
can be grouped to include the following types:
• Surgical
• Medical
• Rejection
• Infection
Surgical complications include vascular problems, such as thrombosis, stenosis, leakage at anastomotic sites, and postoperative bleeding.
Medical complications may include fluid overload or dehydration, electrolyte imbalance, or hypertension.
Rejection
The major problem in organ transplantation is nOt the technical difficulties of surgery, but rather organ rejection, or the tendency of the recipient's body to immediately reject anything that is "nonself. "
Graft rejection is actually a normal immune response to invasion of
foreign matter, the transplanted organ or tissue. Some degree of rejection is normal; however, if the patient is not treated with immunosuppressive drugs, the donor organ would be completely rejected and cease to be viable in 10 days. IS Transplant recipients must receive
ORGAN TRAN5I'I.ANTAT10N
703
immunosuppressive drugs for the rest of their lives to suppress or
minimize rejection of their transplanted organs. The pharmacologic
agents most often used to prevent organ rejection include a double or
triple drug therapy, consisting of a combination of tacrolimus or
cyclosporine with methylprednisolone, and azathioprine or mycophenolate mofetil." See Table 12-1 for common immunosuppressive medications used in organ transplantation.
These immunosuppressive drugs decrease the body's ability to
fight infection. A delicate balance must be reached between suppressing rejection and avoiding infection. Insufficient immunosuppression may result in rejection that threatens the allograft and patient survival, whereas excessive immunosuppression increases
the risk of infection and malignancy. 14 If detected early, rejection
can be minimized or reversed with an increase in daily doses of
immunosuppressive drugs.
When treating postoperative transplant recipients, it is important
to monitOr for adverse side effects of the immunosuppressive drugs.
Immunosuppression protocols now promote the rapid tapering of steroids post transplantation, which diminishes the harsh side effects of the drug. zo
Types of Graft Rejectioll
There arc three types of graft rejection: hyperacute, acute, and
chronic.
I.
Hyperacute rejection is characterized by ischemia and necro-
sis of the graft that occurs from the time of transplant to 48 hours
after transplant· It is believed to be caused by ABO incompatibility
and by cytotox ic antibodies present in the recipient that respond to
tissue antigens on the donor organ. The manifestations of hyperacute
rejection include general malaise and high fever. Rejection occurs
before vascularization of the graft takes place. Hyperacute rejection is