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1090 PART 10: The Surgical Patient

of viral infections (particularly cytomegalovirus) and posttransplant and quality of life across a range of lung conditions. The number of
malignancy. Other less common complications of therapy include procedures reported annually by the International Society of Heart and
seizures (especially when concomitant hypocalcemia is present) and Lung Transplant (ISHLT) has reached 2100. The fifth decade of the
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the acute respiratory distress syndrome (ARDS), possibly due to increased procedure celebrates significant advancements in the technique and in
pulmonary capillary permeability arising from lymphokine stimulation. organ preservation, bridging patients prior to transplantation, mini-
■ SYSTEMIC CORTICOSTEROIDS mizing complications immediately posttransplantation and optimizing
immunosuppression and surveillance in the longer term. Despite these
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Systemic corticosteroids remain a key component of each phase of advances, early postoperative mortality remains high at 12%. In addition,
immunosuppression, and are received by over 95% of patients with these patients can present significant challenges to the intensivist. We
pancreas, heart, lung, and heart-lung transplants. They have multiple are entering an era where previous limits are being revisited in order to
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effects on the immune response. Importantly, steroids block T-cell pro- provide this potential lifesaving technique to more patients. As a result,
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liferation and IL-2 synthesis. The phagocytic function of macrophages we are transplanting an older population and using methods to salvage
is inhibited, and in high doses, corticosteroids prevent neutrophil grafts that would have previously been deemed unacceptable in order
degranulation. to accommodate the expanding recipient pool. These two extremes
Though they effectively attenuate the immune response and help heighten the challenges that are inherent to the care of the lung trans-
prevent allograft rejection, corticosteroids also significantly increase plant recipient. This section will provide an overview of the common
the recipient’s susceptibility to infection. In particular, viral and fun- critical care issues that face this unique patient population.
An important consideration is that steroids can also mask the typical ■ INDICATIONS AND OUTCOMES
gal infections appear to be associated with the use of corticosteroids.
signs of infection. For example, patients on high doses of these medica- Indications: The ISHLT maintains the most complete database of lung
tions may not present with typical signs of peritonitis despite having transplant volumes and performance. The major indications for lung
intra-abdominal infections. As transplant patients typically remain on transplantation according to the ISHLT are listed in Table 115-1 and
steroids chronically, the possibility of adrenal suppression and even Figure 115-2. Chronic obstructive pulmonary disease (COPD) and
overt adrenal insufficiency must be considered if these medications are interstitial pulmonary fibrosis (IPF) remain the two most common
discontinued. Despite their widespread use and important role in most indications. Improvements in transplant techniques and medica-
immunosuppressive regimens, corticosteroids are associated with many tions have facilitated the transplantation of older individuals, hence
of the significant side effects encountered by transplant patients. Insulin the significant increase in proportion of transplants for IPF over the
resistance is common, and the use of oral hypoglycemic agents and past two decades. Bilateral lung transplantation occurs in 62% and is
often insulin may be required. Both cyclosporine and tacrolimus affect a necessity for septic lung diseases such as cystic fibrosis as a single
insulin release and can induce insulin resistance, and may contribute to transplant would become contaminated by the numerous potential
the hyperglycemia. 21-24 Increased sodium and water retention induced drug resistant organisms that reside in the native lung. 30,31 In contrast,
by steroids may aggravate posttransplant hypertension. Impaired wound single lung transplant can be performed in patients with COPD and
healing has been well documented with the use of corticosteroids, IPF. Both single lung and double lung transplant has been performed
and consequently these drugs may contribute to the development in patients with IPAH; however, survival has been shown to be supe-
of postoperative surgical complications. Steroids are associated with rior in those who undergo double lung transplant in this population. 32
increased risk of gastrointestinal hemorrhage, and thus most patients Few data currently exist in the form of randomized control trials to
will be placed on routine stress ulcer prophylaxis, usually with either a support the current guidelines for lung transplantation. Decisions are
histamine (H )-antagonist or a proton-pump inhibitor. Long-term use therefore based on the consensus opinion of experts. The evaluation
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of steroids often leads to osteopenia, overt osteoporosis, and fractures. of potential recipients attempts to identify those with greater prospects
Aseptic necrosis is a dreaded complication of steroid use that can occur of favorable outcomes given the scarcity of lungs available. Broadly, the
at any time following the institution of therapy. Skin changes and fat indication for transplant is a patient who deteriorates despite optimal
redistribution are common. Steroids are also associated with mood medical and surgical therapies. Table 115-2 outlines the various types of
changes and rarely frank psychoses. Because of the significant side lung processes that could progress to end-stage disease and the guide-
effects associated with steroid use, most maintenance immunosuppressive lines for transplantation. Absolute contraindications include malignancy
regimens now include antiproliferation inhibitors such as azathioprine or in the previous 2 years (with the exception of some cutaneous subtypes),
MMF to facilitate the early reduction of the corticosteroid dose. untreatable and advanced dysfunction of another major organ system
■ NEW AGENTS (liver, kidney, or heart if not amenable to percutaneous coronary inter-
vention/bypass/transplant), noncurable extrapulmonary infections such
Recently, there has been increased use of anti–interleukin-2 receptor as HIV and chronic active hepatitis B and C, significant chest wall and
antibodies (basiliximab, daclizumab) during the induction phase. Both
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agents bind to the α-chain of the IL-2 receptor which is only expressed TABLE 115-1 Major indications for Lung Transplantation (1995-2012)
on activated T lymphocytes, and competitively inhibit IL-2–induced
proliferation of active T cells. The advantage of these compounds is that Chronic obstructive pulmonary disease (COPD) 34%
they are not associated with the toxicity produced by antilymphocyte Interstitial pulmonary fibrosis (IPF) 24%
preparations. Their use has been shown to decrease the rate of acute Cystic fibrosis (CF) 17%
rejection following kidney transplant 25,26 without any increase in infec-
tious complications or malignancy. Success has also been seen when α-1-Antitrypsin deficiency emphysema (A1AD) 6%
used in liver and heart transplantation. 27 Idiopathic pulmonary arterial hypertension 3%
Bronchiectasis 3%
LUNG TRANSPLANTATION Sarcoidosis 2.5%
■ INTRODUCTION Retransplant (obliterative bronchiolitis) 1.5%

Since the first successful lung transplant in 1983, lung transplantation Lymphangioleiomyomatosis 1%
has been established as a viable option for a wide range of end-stage Other 8%
lung disease, with increasing evidence that it can improve survival International Society for Heart and Lung Transplantation 30

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