الفهرس 
Heart Lung TransplantationOnly 14 pages are availabe for public view
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Abstract
The first heart-lung transplantation was performed in 1981 in a patient with pulmonary arterial hypertension .The indications for the procedure were subsequently expanded to include patients with severe parenchymal lung disease and congenital heart disease complicated by Eisenmenger syndrome(Stehlik et al., 2010)
Early post-operative management of the newly transplanted heart allograft is focused on maintenance of hemodynamic stability as the allograft restores normal cardiac function to the chronic heart failure patient. While the graft begins to support the recipient as soon as separation from CPB is complete, there is invariably a period of time during which the allograft and its recipient require active hemodynamic management and support. The nature and duration of this support is determined by several factors including the quality and preservation of the donor heart and pre-operativecondition of the recipient. (Pavri et al .,1995)
Recipient factors such as vasomotor tone, severity and reversibility of pulmonary vascular hypertension, pulmonary function, degree of pre-operative fluid overload, renal function, destabilizing post-operative bleeding, and immunologic compatibility may have aprofound effect upon early post-operative management. Additional factors such as Heart trams plantation surgical technique (biatrial vs.bicaval vs. orthotopic vs. heterotopic) and donor/recipient size matching affect post-operative management strategies. (Pavri et al .,1995)
Anti-infective agents are administered early after HT to prevent post-operative and opportunistic infections, and to continue treatment of pre-existing chronic infections (such as chronic VAD-related bacterial infections). Specific guidelines for the prevention and treatment of opportunistic infections will be provided in separate guidelines. (Leonar et al,2003)
Serum antibodies directed against human leukocyteantigens (HLA) have been associated with allograft rejection, dysfunction, and loss. This was first demonstrated by Pateland Terasaki, who documented poor survival of renal allografts in recipients whose serum caused lysis of donor leukocytes in an in vitro crossmatch test. (St Goar et al., 1992)
Postoperative end myocardial biopsies are performed at weekly intervals for 2-4 weeks to assess cardiac rejection. Chest radiographs and spirograms are routinely obtained to evaluate for the presence of pulmonary rejection or infection. If either entity is considered possible, bronchoalveolar lavage with transbronchial biopsy is performed to streamline the differential diagnosis and direct therapy. (Miller et al., 2004)
Ischemia-reperfusion injury represents the most frequent cause of early mortality and prolonged ICU stay. A variety of factors such as poor preservation, prolonged ischemic time, or unsuspected donor lung pathology such as contusion or aspiration play a role in its development. The condition is characterized by noncardiogenic pulmonary edema and progressive lung injury over the first few hours following implantation (Figs 3A, 3B). The process can evolve into severe diffuse alveolar damage (Fig 3C) requiring maximal ventilatory support and even institution of extracorporeal membrane oxygenation (ECMO).Fortunately, severe reperfusion injury is not so commonly encountered in recent years. Superior strategies of lung preservation have evolved .( Matsuzaki et al.,1993).
When a lung transplant recipient is admitted to the ICU, their immunosuppressive regimen needs to be examined and often modified based on their indication for admission. For this reason, it is imperative that intensivists are knowledgeable of basic pharmacotherapy of the common agents used. The majority of lung transplant recipients are treated with a combination of a calcineurin inhibitor plus a npurine synthesis antagonist (80%). (Trulock et al,2003)
Lung transplant recipients are at increased risk for a variety of infectious complications, due to the chronic immunosuppression and abnormal physiology of the post transplant lung. Infections with typical bacterial pathogens as well as opportunistic infections such as CMV are common. Collectively, infections represent the leading cause of death in the early postoperative period and remain an important cause of morbidity and mortality throughout the post transplant period. These infectious complications may result in respiratory failure (Charman et al.,2002).
Both acute and chronic lung allograft rejection contribute substantially to morbidity seen in lung transplant recipients. chronic lung transplantation remains the major limitation to long-term success in lung transplantation today. Hyperacute rejection has been only anecdotally reported in the literature .( Magro et al.,2003). .
The most common malignancies encountered in the post-transplant setting—and those on which this review focuses—are nonmelanoma skin cancers (NMSCs) (up to 82% of transplant recipients), PTLD (1%–11%), and KS (6%) . Others, including non-Kaposi’s sarcomas and gastrointestinal, urogenital, and thoracic tumors, have also been reported (Amital et al., 2006).