Info

short-lived myocardial depression. The post-reperfusion syndrome responds readily to small amounts of epinephrine (10-50 |ig). However, severe bradycardia or even sinus arrest within the first few minutes after graft reperfusion has been seen in a few patients, but fortunately is quickly reversed by boluses of epinephrine (100-250 |ig) and chest compressions.

During the remainder of the neohepatic stage, cardiac output returns to the values seen during the preanhepatic stage. Sometimes excessive vasodilation associated with graft reperfusion persists for 1-2 h, requiring low-dose epinephrine or dopamine infusion. Normally, the graft starts to be metabolically active very early after reperfusion, and therefore CaCl2 and NaHCO3 are rarely necessary to maintain a normal metabolic state.

Fluid and Transfusion Management

Maintaining normovolemia intraoperatively is probably the most important task for the anesthesiologist. At the same time, it is probably also the most difficult task. The main reason for maintaining the patient's volume status is that this is the only way for the cardiovascular system to remain hyperdynamic during the procedure. Cardiac filling pressures may not accurately reflect the volume status of the patient, because the compliance of the heart and thoracic cage changes significantly during the transplant as the result of the use of retractors and varying pressure on the diaphragm. TEE and determination of RVEDV probably allow a more accurate estimation of the patient's volume status.

Although the average blood loss has gradually decreased over the last 15 years, it is impossible to predict blood loss in individual patients. Indeed, blood loss can still be substantial (more than 10 times blood volume). Intraoperative autologous transfusion (cell saver) may reduce the need for packed red blood cells from the blood bank. However, virtually all coagulation factors and platelets are removed during the process. Most anesthesiologists aim for a hematocrit of 25-30%, which should be sufficient to provide adequate oxygen transport. Because most patients have coagulopathy, one unit of fresh frozen plasma is usually administered for each unit of transfused packed cells. More fresh frozen plasma may be necessary to correct coagulopathy. Cryoprecipitate and platelets are given based on coagulation tests. Most liver transplant anesthesiologists use a type of rapid infusion device to allow transfusion of large amounts of fluids and blood products, allowing for adequate warming of the solution. Transfusion devices ideally should have air detectors to avoid intravenous infusion of air. A commonly used transfusion system is the Rapid Infusion System® (Haemonetics, Inc. Braintree, Mass.) (Fig. 14.1). This device allows transfusion of up to 1.5 L/min of a warmed blood mixture.

Coagulation Management

Intraoperative coagulopathy is the result of preoperative coagulopathy, thrombocytopenia, and platelet dysfunction; intraoperative dilution of coagulation factors and platelets; excessive fibrinolysis; and hypothermia. Although the coagulopathy that occurs during liver transplantation usually can be corrected by transfusion of fresh frozen plasma, cryoprecipitate, and platelets, pharmacologic

Turbo Metabolism

Turbo Metabolism

Forget Silly Diets-They Don't Work. Weight loss has got to be the most frustrating experience for many people, young and old alike. Eating foods that are just horrible, denying yourself foods you truly love and enjoy. Exercising, even though you absolutely hate exercising, and end up stiff as a board with no results.

Get My Free Ebook


Post a comment