Liver transplantation surgical procedures

Drug absorption is highly variable in neonates and infants [21,22]. Older children appear to have absorption patterns similar to adults unless chronic illness or surgical procedures alter absorption. Differences in bile excretion, bowel length, and surface area probably contribute to the reduced bioavailability of cyclosporine seen in pediatric liver transplant patients [22a]. Impaired absorption has also been observed in severely malnourished children [22b]. A rapid GI transit time may contribute to the malabsorption of carbamazepine tablets, which has been reported in a child [23]. Selection of a more readily available bioavailable dosage form, such as chewable tablets or liquids, should be promoted for pediatric patients. 

While liver transplantation represents a significant development for those with hver disease, a need continues to exist for therapies that address the risks of this major surgical procedure. Furthermore, the supply of tissue for transplantation will be a continuing problem. Alternative techniques are still experimental but in many cases appear promising. The next section introduces these techniques and provides an effective transition to the apphcation of reticulated polyurethanes. 

In addition to improved survival for patients who undergo TACE for unresectahle disease, there have been reports of patients whose tumor has shrunk enough to permit resection or liver transplantation and provide a chance for cure. Despite these benefits, TACE is considered a palliative treatment option. Surgical resection is the only procedure that can be performed with curative intention, therefore, TACE should be reserved for patients who are not surgical candidates. This is the only absolute contraindication to TACE. Table 10.2 summarizes a list of relative contraindications. 

Xenotransplantation is a medical procedure in which live cells, tissues, or whole organs are surgically transplanted from one animal species to another, such as transplanting pig hearts or baboon livers into humans. It is a potential solution to the shortage of human organs and tissues available for transplant. Xenotransplantation also offers many other potential therapeutic applications, including the treatment of diabetes, spinal cord injury, and Parkinson s disease. However, the use of xenotransplantation has raised many ethical and safety concerns. 

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