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CHAPTER 115: The Transplant Patient 1099

donors. In this procedure, the right hepatic lobe from a donor with operation, but if the graft is functioning properly they should return
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a compatible blood type is implanted into the recipient following to normal—usually within 1 day. Abrupt changes in any of the func-
hepatectomy of the diseased organ. This procedure requires much tion parameters or the absence of evidence of decline of their original
more delicate dissection because the living donor partial liver graft levels should prompt further investigation into whether the graft is
has a much smaller sized hepatic artery, vein, and pulmonary vein. functioning appropriately with an ultrasound and Doppler study to
Given the small size, the reconstruction is technically difficult and ensure adequate hepatic artery and vein flow. A Doppler study is rou-
patients are at higher risk of having postoperative bleeding compli- tinely performed after living-donor transplants.
cations. Biliary reconstructions are completed last and have shifted
largely from hepaticojejunostomies to duct-to-duct anastomosis. Volume Status and Hemodynamics: A coagulopathy can persist in the
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Along with an often substantially reduced waiting time for the proce- postoperative period and close monitoring of hemoglobin is necessary
dure, living-related transplants may also allow for better selection of to monitor for signs of bleeding. Most centers advocate continuing to
healthy donors (and consequently donor organs) and a considerably maintain a low central venous pressure in attempt to minimize liver con-
decreased cold ischemic time. The elective nature of the procedure gestion and reduce the risk of bleeding. The traditional perspective to
also enables potential recipients to be medically stabilized preop- fluid status intraoperatively and postoperatively was a conservative one
eratively. The major disadvantage is the small but significant risk with some institutions actively aiming for lower central venous pressures
of complications for the donor. Biliary complications may occur in (CVP). This is believed to decrease the potential congestion to the fresh
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up to 6% of donors, and other complications of abdominal surgery graft in order to maximize graft function and minimize blood loss. A
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such as wound infection may develop; the reported mortality of more recent review has demonstrated that maintaining a low CVP is
donors following living-donor liver transplant is 0.28%. One study not associated with any benefit with respect to immediate postopera-
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suggests that in the United States approximately 99% of living donors tive graft function, graft survival, or patient survival. Enhancing and
are genetically or emotionally related to the recipient, creating optimizing oxygen delivery through adequate cardiac output (optimized
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important ethical and psychosocial challenges. preload and contractility) should be the primary focus of postoperative
fluid and hemodynamic management with caution not to overresusci-
Blood Loss: In the late 1980s, the average red cell transfusion was tate or underresuscitate the unstable posttransplant patient given the
20 units per orthotopic liver transplant. This rate of transfusion has sensitivity of the graft to under perfusion and hepatic congestion. The
decreased dramatically to as low as 2 units in 2003 after improvements hyperdynamic circulatory state that characterizes portal hypertension
in transplant technique, changes in patient characteristics, and altera- will often persist in the postoperative period. The increased cardiac
tions in transfusion triggers. Anesthesiologists attempt to decrease output and decreased systemic vascular resistance may mimic sepsis
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surgical blood loss by maintaining a low central venous pressure in order and make the interpretation of hemodynamic measurements difficult.
to minimize graft congestion. 78 The management of the patient with preoperative portopulmonary
Hemodynamic Challenges: Refractory hypotension is a relatively com- hypertension can be extremely challenging. These patients will often
mon event during reperfusion and may require catecholamine encounter pulmonary hemodynamic instability due to acute right
support as well as fluids in addition to correction of acid-base and ventricular decompensation and may have increased cardiopulmonary
electrolyte abnormalities. Vasoplegic syndrome (VS) and postreper- mortality, especially if the preoperative mean pulmonary artery pressure
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fusion syndrome (PRS) represent the most severe form of refractory is greater than 35 mm Hg. If invasive hemodynamic monitoring has not
hypotension that can be difficult to treat given its refractory nature already been established with a pulmonary artery catheter, it should be
to standard vasopressors. Initially described in cardiac surgery, VS is considered to guide therapy in these patients. Specific pulmonary vaso-
characterized by profound vasodilation with a low systemic vascular dilators such as inhaled nitric oxide or nebulized prostaglandins may
resistance and high cardiac index. PRS is characterized by severe be required in the setting of right ventricular dysfunction in order to
hypotension after graft reperfusion defined as a greater than 30% preserve cardiac output. Strategies should also focus on attempts to aug-
decrease in systolic pressure during the first 5 minutes after graft ment contractility, while preserving coronary perfusion and minimizing
perfusion that lasts at least 1 minute. The cause of the hypotension is RV overload (and in-turn hepatic congestion).
not completely understood, but is believed to be associated with dys- A system for classifying patients based on their anticipated need for
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regulation of nitric oxide synthesis and vascular smooth muscle cell fluid and electrolyte replacement has been proposed and advocated by
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guanylate cyclase activation with resultant vasodilation. 79 several experts. Such an approach may be practically useful in that it
creates a framework to understand the hemodynamic considerations for
■ POSTOPERATIVE MANAGEMENT a given patient (Table 115-12). According to this classification, a patient
Assessment of Graft Function: Postoperative monitoring of graft func- with class I liver disease can be expected to have a normal postoperative
response to intravenous fluid therapy. Patients with class II or III liver
tion includes serial measurements of INR, total bilirubin, lactate, disease will have more ascites, leading to greater fluid and protein loss
and glucose in addition to transaminases. The normal initial rise in intraoperatively, and can be anticipated to need more fluids postopera-
the patient’s transaminase levels in the first 1 to 2 days following the tively. Patients with class IV disease require the closest monitoring and
transplant is expected to normalize within a few days. Some centers
try to avoid the administration of fresh frozen plasma immediately
postoperatively in deceased donor transplants (unless there is concern
about active bleeding) given that it will interfere with the ability to TABLE 115-12 Classification of End-Stage Liver Disease Severity for the
monitor the synthetic function (using INR) of the new graft. Given Purposes of intensive Care Unit Management
the inherent higher risk of bleeding from the raw surface of the liver,
living-donor transplant recipients are more commonly treated for Hyperdynamic Portopulmonary Cardiac
coagulopathies. Glucose should be monitored frequently during the Class Circulation Hyponatremia Malnutrition Hypertension Dysfunction
ICU stay, as liver failure will often result in refractory hypoglycemia. I − − − − −
Conversely, the use of corticosteroids may lead to insulin resistance II + +/− − − −
and hyperglycemia, which should be treated appropriately. Bilirubin
often remains elevated for many days following the transplant, but III ++ ++ − − −
should be followed closely as abrupt changes may herald complica- IV ++ ++ + + +
tions involving the biliary tree or the vascular supply to the liver. Adapted with permission from Lowell J, Shaw B Jr. Critical care of liver transplant recipients. In: Maddrey WC,
Serum lactate levels are frequently elevated immediately following the Schiff ER, Sorrell MF, eds. Transplantation of the Liver. Philadephia, PA: Lippincott, Williams & Wilkins; 2001.

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