Hemoperfusion with polymyxin B-immobilized fiber column improves liver function after ischemia-reperfusion injury

Extracorporeal therapies for post-liver transplant recipient: The road less traveled

Extracorporeal therapies have a definite role in patients with acute liver failure, acute on-chronic liver failure, and progressive chronic liver disease. They act as a bridge-to-transplant in these patients. With the increasing success of liver transplantation, the immediate postoperative complication spectrum continues to expand. Extracorporeal therapies can play an important role in managing these complications. However, the literature on extracorporeal therapies in the post-liver transplant period is limited. This review article discussed various extracorporeal therapies that are still evolving or marred by limited evidence but can improve patient outcomes. These extracorporeal therapies can be divided into two subgroups: (1) Therapies for infective complications. Endotoxin and cytokine adsorption columns; and (2) Therapies for noninfective complications like small for size syndrome, primary allograft nonfunction, early allograft dysfunction, hyperacute rejection, hepatopulmonary syndrome, etc. (plasma exchange, double plasma molecular adsorption, molecular adsorbent recirculation system, and extracorporeal membrane oxygenation, among others).

Targeting endotoxin in the treatment of sepsis

The role of endotoxin in the genesis of sepsis has long been recognized and multiple treatments aimed at neutralizing it have been studied. Endotoxin can be bound by antibodies (whose role as a therapeutic agent is unlikely), binding proteins such as BPI or human lactoferrin (effectiveness debated and promising respectively) and phospholipid emulsion (which has not improved outcomes in a recent study). Alternatively, the action of endotoxin could be blocked by lipid A analogs (initial study showed no overall benefit and another large trial is near completion targeting a subpopulation of that study). Finally, endotoxin can be bound by polymyxin B embedded in hemoperfusion cartridges. The later treatment has been used for more than a decade in Japan. Since both pre-clinical rationale and studies support the targeting of endotoxin to ameliorate the pro-inflammatory and pro-coagulation response of severe sepsis, this therapeutic intervention is being pursued.