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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