Chapter 44 - Liver transplantation in children: post-transplant care

Summary

Introduction

Management in the early postoperative period requires the coordinated efforts of the transplant team and the pediatric intensive care staff. Patients with end-stage liver disease undergoing liver transplantation require meticulous medical care in the immediate postoperative period to assure adequate perfusion of the graft and avoid exacerbation of injury to other organ systems. Care should be guided by attention to the pretransplant physiologic state, which might include advanced portal hypertension and compromise to other organ systems, such as seen in hepatorenal or hepatopulmonary syndrome. Specifics of the transplant procedure including information regarding blood loss, challenging vascular anastomosis, and graft function following reperfusion are also essential considerations in the management plan.

General principles of early postoperative management

General aspects of the surgical procedure and common intraoperative complications are reviewed in Chapter 43. It is not uncommon for recipients to experience blood loss and replacement that exceeds their estimated blood volume and which can result in third-space fluid losses and pulmonary edema. Likewise, placement of a graft that exceeds the mass of the explanted liver can increase intra-abdominal pressure and impede ventilation. Management of fluid and cardiovascular support to maintain graft perfusion but limit pulmonary complications can be challenging. Monitoring of changes in arterial blood pressure and central venous pressure can detect acute intra-abdominal hemorrhage or vasodilatation caused by cytokine release related to allograft necrosis or systemic infection. The overwhelming majority of children remain intubated during the first to 12 to 24 hours following the procedure even when they have not had evidence of pre-existing lung disease. Likewise, many receive ionotropic support during the anhepatic and postperfusion phases of the procedure, which is gradually tapered off following abdominal closure. Cardiac function may be depressed during the procedure because of the circulation of cytokines and of lactic acid released from the graft at reperfusion and it may not be restored to normal until the metabolic function of the liver is re-established. One of the classic hallmarks of primary non-function of the graft is cardiovascular instability and persistent lactic acidosis. Although many patients are relatively fluid overloaded at the conclusion of the procedure, efforts are not made to encourage diuresis until at least 24 to 36 hours following the procedure because of concerns regarding hypoperfusion of the graft resulting from a sudden drop in intravascular volume and blood pressure.