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3. Hyperacute rejection is caused by:
CHAPTER 11
A. Preformed antibodies. B. B-cell–generated antidonor antibodies. C. T-cell–mediated allorejection. D. Nonimmune mechanism.
Transplantation
4. Which is TRUE about mycophenolate mofetil’s (MMF) use in transplantation? A. It is safe to use in pregnancy. B. It has fewer gastrointestinal (GI) side effects than
azathiaprine (AZA).
C. Like AZA, it interferes with lymphocyte proliferation
by interfering with purine synthesis.
D. Its use is limited to induction immunosuppression.
Answer: A
Hyperacute rejection, a very rapid type of rejection, results in irreversible damage and graft loss within minutes to hours after organ reperfusion. It is triggered by preformed antibod­ies against the donor’s HLA or ABO blood group antigens. These antibodies activate a series of events that result in dif­fuse intravascular coagulation, causing ischemic necrosis of the graft. Fortunately, pretransplant blood group typing and cross-matching (in which the donor’s cells are mixed with the recipient’s serum, and then the cells are observed for any destruction) have virtually eliminated the incidence of hyper­acute rejection. (See Schwartz 11th ed., p. 358.)
Answer: D
The antimetabolite, AZA is converted to 6-mercaptopurine and inhibits both the de novo purine synthesis and salvage purine synthesis. AZA decreases T-lymphocyte activity and decreases antibody production. It has been used as a first-line agent in transplant recipients for >40 years, but it became an adjunctive agent after the introduction of cyclosporine. With the development of newer agents such as MMF, the use of AZA has decreased significantly. However, it is preferred in recipients who are considering conceiving a child because MMF is teratogenic and can cause birth defects. Use of AZA remains an option for recipients who cannot tolerate the GI side effects of MMF.
The most significant side effect of AZA, often dose-related, is bone marrow suppression. Leukopenia is often reversible with dose reduction or temporary cessation of the drug. Other significant side effects include hepatotoxicity, pancreatitis, neoplasia, anemia, and pulmonary fibrosis. Its most signifi­cant drug interaction is with allopurinol, which blocks AZA metabolism, increasing the risk of pancytopenia. Recom­mendations are to not use AZA and allopurinol together, or if doing so is unavoidable, to decrease the dose of AZA by 75%.
MMF has now been incorporated into routine maintenance regimens after many solid organ transplants. Mycophenolate is the prodrug of mycophenolate acid, derive from Penicillium fungi. Mycophenolate acid is an inhibitor of inosine mono­phosphate dehydrogenase (IMPDH) involved in the de novo pathway of purine synthesis. MMF is available in capsules (250 and 500 mg); the starting dose is 1 g twice daily. (See Schwartz 11th ed., p. 361.)
5. Compared to cyclosporin, tacrolimus: A. Can be given intravenously, but cyclosporin must be
given orally. B. They both are calcineurin inhibitors. C. Levels do not need to be monitored. D. Is more associated with gingival hyperplasia and hir-
sutism than cyclosporin.
Answer: B
Cyclosporin binds with its cytoplasmic receptor protein, cyclophilin, which subsequently inhibits the activity of cal­cineurin, thereby decreasing the expression of several critical T-cell activation genes, the most important being for IL-2. As a result, T-cell activation is suppressed. Cyclosporin can be given intravenously or orally to maintain trough levels of 250 to 350 ng/mL for the first 3 months posttransplant; then it can be tapered to 150 to 250 ng/mL.
The metabolism of cyclosporine is via the cytochrome P450 system, resulting in many significant drug interactions (see Table 11-1). Calcineurin inhibitors are nephrotoxic and con­strict the afferent arteriole in a dose-dependent, reversible manner (Table 11-2). They also can cause hyperkalemia and hypomagnesemia. Several neurologic complications, including headaches, tremor, and seizures, also have been reported.
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TABLE 11-1 Side effects and drug interactions of the main immunosuppressive drugs
Other Medications That
Common Side Effects
Cyclosporine (CSA) Hypertension, nephrotoxicity,
hirsutism, neurotoxicity, gingival hyperplasia, hypomagnesemia, hyperkalemia
Tacrolimus (FK506) Hypertension, nephrotoxicity,
alopecia, hyperglycemia, neurotoxicity, hypomagnesemia, hyperkalemia
Sirolimus Thrombocytopenia and
neutropenia, elevated cholesterol, extremity edema, impaired wound healing
Mycophenolate
mofetil
Corticosteroids Hyperglycemia, osteoporosis,
Azathioprine Leukopenia, anemia,
ACE-I = angiotensin-converting enzyme inhibitor; ARB = angiotensin receptor blocker; NSAID = nonsteroidal anti-inflammatory drug; TMP-SMX = trimethoprim-sulfamethoxazole
Leukopenia,
thrombocytopenia, GI upset
cataracts, myopathy, weight gain
thrombocytopenia, neoplasia, hepatitis, cholestasis
Increase Blood Levels
Verapamil, diltiazem,
clarithromycin, azithromycin, erythromycin, azole antifungals, protease inhibitors, grapefruit juice
Verapamil, diltiazem,
clarithromycin, azithromycin, erythromycin, azole antifungals, protease inhibitors, grapefruit juice
Verapamil, diltiazem,
clarithromycin, azithromycin, erythromycin, azole antifungals, protease inhibitors, grapefruit juice
Cholestyramine, antacids Bone marrow suppression:
Bone marrow suppression:
Other Medications That Decrease Blood Levels
Isoniazid, carbamazepine,
phenobarbital, phenytoin, rifampin, St. John’s wort
Isoniazid, carbamazepine,
phenobarbital, phenytoin, rifampin, St. John’s wort
Isoniazid, carbamazepine,
phenobarbital, phenytoin, rifampin, St. John’s wort
Other Medications That Potentiate Toxicity
Nephrotoxicity: ganciclovir,
aminoglycosides, NSAIDs, ACE-Is, and ARBs
Nephrotoxicity: ganciclovir,
aminoglycosides, NSAIDs, ACE-Is, and ARBs
valganciclovir, ganciclovir, TMP-SMX
allopurinol, sulfonamides
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Transplantation
The calcineurin inhibitor tacrolimus (Prograf) is now the backbone of most immunosuppressive regimens. Tacro­limus acts by binding FK506-binding proteins (FKBPs), causing roughly 10 to 100 times more potent inhibition of IL-2 production than cyclosporine (which acts by binding cyclophilins). It can be given intravenously, orally, or sublin­gually to maintain trough levels of 8 to 12 ng/mL for the first 3 months posttransplant; then it can be tapered to 6 to 10 ng/mL. The metabolism of tacrolimus is via the cytochrome P450 system, resulting in many significant drug interactions (see Table 11-1). Tacrolimus causes a higher incidence of new-onset diabetes posttransplant than does cyclosporine. Other side effects include alopecia, nephrotoxicity, neuro­toxicity, hypertension, hyperkalemia, hypomagnesemia, and an increased incidence of certain types of infection. (See Schwartz 11th ed., p. 362.)
TABLE 11-2 Drug interactions and side effects associated
with calcineurin inhibitors
Interactions Medications
Inhibition of
metabolism
Induction of
metabolism
Hyperkalemia Potassium-sparing diuretics, angiotensinconverting
Nephrotoxicity Nonsteroidal anti-inflammatory drugs,
Clarithromycin, erythromycin, azole antifungals,
diltiazem, verapamil, nicardipine, amiodarone, grapefruit juice, ritonavir, azithromycin
Nevirapine, rifampin, St. John’s wort, carbamazepine,
phenobarbital, phenytoin, caspofungin
enzyme inhibitors (ACE-Is), angiotensin receptor blockers (ARBs), β-blockers, trimethoprim-sulfamethoxazole
aminoglycosides, amphotericin, ACE-Is, ARBs
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6. The most significant side effect of Sirolimus is:
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A. Anemia. B. Leukopenia. C. Impaired wound healing. D. Hypertriglyceridemia.
Transplantation
7. In the prevention of graft rejection, cyclosporin: A. Blocks transcriptions of interleuking-1 (IL-1) and
tumor necrosis factor (TNF). B. Inhibits lymphocyte nucleic acid metabolism. C. Results in rapid decrease in the number of circulating
T lymphocytes. D. Selectively inhibits T-cell activation.
Answer: D
The first mammalian target of rapamycin (mTOR) inhibitors to enter clinical use was sirolimus (Rapamune). The mTOR inhibitors bind to FK506-binding protein (FKBP), and the sirolimus-FKBP complex binds to mTOR. Sirolimus also inhibits proliferation of vascular smooth muscle cells, possi­bly easing the vasculopathy and progressive fibrosis that can affect allografts. Sirolimus is a substrate for CYP3A4/4 and has many significant drug interactions. Sirolimus has been used in a variety of combinations for maintenance immuno­suppression, alone or in conjunction with one of the calci­neurin inhibitors. In such combinations, sirolimus usually is used to help withdraw from, or completely avoid, the use of steroids. It also has been used as an alternative to tacrolimus or cyclosporine, in a calcineurin-sparing protocol. One of the most significant side effects of sirolimus is hypertriglyceride­mia, a condition that may be resistant to statins and fibrates. (See Schwartz 11th ed., p. 361.)
Answer: D
Corticosteroids have had a role in immunosuppression since the beginning of the field of transplantation. Despite numer­ous attempts to limit or discontinue their use, they remain an integral component of most immunosuppressive protocols, for both induction and maintenance. Moreover, they are often the first-line agents in the treatment of acute rejection. The introduction of cyclosporine in the early 1980s dramatically altered the field of transplantation by significantly improving outcomes after kidney transplantation. Cyclosporine binds with its cytoplasmic receptor protein, cyclophilin, which sub­sequently inhibits the activity of calcineurin, thereby decreas­ing the expression of several critical T-cell activation genes, the most important being for IL-2. As a result, T-cell activa­tion is suppressed. (See Schwartz 11th ed., p. 362.)
8. Late infections in transplant recipients are: A. Generally due to suppression of humoral immunity. B. Common bacterial infections. C. Depression of cell-mediated immunity renders recip-
ients less susceptible to opportunistic infections.
D. Depression of cell-mediated immunity renders recip-
ients more susceptible to viruses, fungi, and parasites.
Answer: D
Late infections primarily are due to chronic immunosup­pression, specifically the depression of cell-mediated immu­nity that renders recipients susceptible to viruses, fungi, and parasites.
Members of the herpesvirus group are the most common etiologic agents of viral infections posttransplantation, with herpes simplex virus (HSV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) being the most prominent. Pre­transplant exposure to viruses may confer immunity. Recipi­ents who are seronegative for HSV, CMV, and/or EBV have a higher incidence of posttransplant infections, especially if they receive donor allografts from seropositive donors. After 6 months posttransplant, the risk of invasive fungal infections is closely associated with environmental exposures. Blastomy- ces dermatitidis grows in moist soil in the Midwest and South­east regions of the United States. Diagnosis is confirmed by biopsy; the preferred treatment is IV amphotericin B. (See Schwartz 11th ed., p. 363.)
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9. Compared to donation after rain death, donation after cardiac death (DCD): A. Most patients meet the criteria for brain death. B. Is associated with increased warm ischemia time. C. In both procurement surgeons wait until cessation of
cardiac activity.
D. Transfer to the operating room occurs after cessation
of cardiac activity.
Answer: B
Given the severe shortage of donor organs, DCD—also known as donation by non–heart-beating donors (NHBDs)—was reintroduced to the transplant community in the 1990s. The category of DCD (Maastricht classification) was initially proposed at an international workshop and is now widely adopted for organ procurement. Currently, most NHBDs in the United States meet Maastricht classification III; that is, they have suffered a devastating injury with no chance of a mean­ingful recovery but do not meet the criteria for brain death. After consent for donation is obtained from the next of kin, the donor’s life support is removed. After the cessation of car­diac and respiratory function, organ procurement commences. DCD procurement protocols vary between states; religious and cultural differences need to be taken into consideration. The surgical team must be familiar with, and respect, the local pro­tocol. With cardiac death (as opposed to brain death), warm ischemic injury to organs can occur during the period between circulatory cessation and rapid core cooling through perfu­sion of preservation solution. However, the difference in long­term outcomes is negligible for recipients of organs from either type of donor. Still, a significant percentage of liver grafts pro­cured after cardiac death, especially those with >25 minutes of warm ischemic time, develop devastating ischemic cholangi­opathy and fail. (See Schwartz 11th ed., p. 365.)
CHAPTER 11
Transplantation
10. Compared to deceased donor kidneys, living donor kid­ney transplants: A. Must be from human leukocyte antigen (HLA) iden-
tical relatives.
B. Are associated with improved posttransplant
outcomes. C. Increase in delayed graft function. D. Have lower 1-year graft survival rate.
11. The most common cause of renal failure in the United States is: A. Chronic glomerulonephritis. B. Chronic pyelonephritis. C. Diabetes mellitus. D. Obstructive uropathy.
Answer: B
The advantages of a living donor kidney transplant include bet­ter posttransplant outcomes, avoidance of prolonged waiting time and dialysis, and the ability to coordinate the donor and recipient procedures in a timely fashion. Living donor kidney recipients enjoy better long-term outcomes, a low incidence of delayed graft function, and reduced risks of posttransplant complications. Furthermore, the elective nature of living donor kidney transplants provides unique opportunities for recipient desensitization treatment if the donor and recipient are ABO­incompatible or if the HLA cross-match results are positive.
Posttransplant outcomes have continued to improve. In 2015, the 1-year graft survival rate with a living donor kidney was nearly 98%; with a deceased donor kidney, the rate was approximately 95%. (See Schwartz 11th ed., p. 368.)
Answer: C
Diabetes and hypertension are the leading causes of chronic renal disease. Concomitant cardiovascular disease (CVD) is a common finding in this population. An estimated 30% to 42% of deaths with a functioning kidney graft are due to CVD. Therefore, assessment of the potential kidney trans­plant candidate’s cardiovascular status is an important part of the pretransplant evaluation. (See Schwartz 11th ed., p. 369.)
12. Kidney grafts are placed in adult recipients: A. Intraperitoneally, with anastomosis to inferior vena
cava and aorta. B. Orthotopically, with anastomosis to native renal vessels. C. Heterotopically, in the retroperitoneal space with
anastomosis to iliac vessels. D. Orthotopically, with anastomosis to the adrenal
artery and veins.
Answer: C
Kidney allografts usually are transplanted heterotopically. The iliac fossa is recognized as the ideal position because of its proximity to the recipient’s bladder and iliac vessels. Retroperitoneal allograft placement also allows easy access for percutaneous biopsies and interventions for ureteral complications. In general, the donor’s renal artery and vein are anastomosed to the recipient’s external iliac vessels in an
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CHAPTER 11
Transplantation
FIG. 11-1. Vascular anastomoses of kidney transplant. A. Arterial anastomosis: donor renal artery with Carrel patch to recipient external
iliac artery, end-to-side. B. Venous anastomosis: donor renal vein with caval extension conduit to recipient external iliac vein, end-to-side.
13. The most important factor in determining whether to perform a transplant between a specific donor and recip­ient is: A. Mixed lymphocyte culture assays of the donor and
recipient.
B. Human leukocyte antigen (HLA) type of the donor
and recipient. C. ABO blood types of the donor and recipient. D. Peripheral T-cell count of the recipient.
end-to-side fashion (Fig. 11-1). In recipients with a severely calcified iliac artery, the internal iliac artery can be used as an alternative, and in select cases, an endarterectomy must be performed. (See Schwartz 11th ed., p. 370.)
Answer: C
ABO blood typing and HLA typing (HLA-A, -B, and -DR) are required before a kidney transplant. The method of screen­ing for preformed antibodies against HLA antigens (because of prior transplants, blood transfusions, or pregnancies) con­tinues to evolve. The panel-reactive antibody (PRA) assay is a screening test that examines the ability of serum from a kid­ney transplant candidate to lyse lymphocytes from a panel of HLA-typed donors. A numeric value, expressed as a percent­age, indicates the likelihood of a positive cross-match with a donor. A higher PRA level identifies patients at high risk for a positive cross-match and therefore serves as a surrogate marker to measure the difficulty of finding a suitable donor and the sub­sequent risk of graft rejection. (See Schwartz 11th ed., p. 370.)
14. After a kidney transplant, a recipient was producing at least 100 cc of urine/hour. Eight hours after completing the transplant you are informed that their urine output is now 5 cc over the past hour. Likely etiology is: A. Hypovolemia due to postoperative bleeding. B. Acute tubular necrosis (ATN). C. Graft thrombosis. D. All of the above.
Answer: D
Suddenly decreased or minimal urine output requires imme­diate attention. A change in volume status is the most com­mon cause, but other culprits include blockage of the urinary catheter, urinary leak, vascular thrombosis, hypotension, drug-related nephrotoxicity, ATN, and rejection (all of which must be thoroughly investigated). Diagnostic studies such as Doppler ultrasound, nuclear renograms, or biopsies should be considered.
Postoperative bleeding is an uncommon event after a kid­ney transplant. Recipients on anticoagulation or antiplatelet treatments are at increased risk. Signs and symptoms (such as an expanding hematoma over the surgical site, increased pain over the graft, a falling hemoglobin level, hypotension, and tachycardia) should arouse suspicion of hemorrhage. Doppler ultrasound is useful to establish the underlying cause. Surgical exploration seldom is required because the accumulated hematoma tamponades the bleed. Indications for surgical exploration include ongoing transfusion require­ment, hemodynamic instability, and graft dysfunction from
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15. Postrenal transplant graft thrombosis usually occurs: A. Within 2–3 days. B. Within 2 weeks. C. Within the first month. D. Within the first 5 months.
hematoma compression. For recipients on anticoagulation or antiplatelet treatments, the threshold for surgical exploration is lower. Small unligated vessels at the donor’s renal hilum or recipient’s retroperitoneum are likely sources of bleeding.
One of the most devastating postoperative complications in kidney recipients is graft thrombosis. It is rare, occur­ring in fewer than 1% of recipients. The recipient risk factors include a history of recipient hypercoagulopathy and severe peripheral vascular disease; donor-related risk factors include the use of en bloc or pediatric donor kidneys, procurement damage, technical factors such as intimal dissection or tor­sion of vessels, and hyperacute rejection. Graft thrombosis usually occurs within the first several days posttransplant. Acute cessation of urine output in recipients with brittle post­transplant diuresis and the sudden onset of hematuria or graft pain should arouse suspicion of graft thrombosis. Doppler ultrasound may help confirm the diagnosis. In cases of graft thrombosis, an urgent thrombectomy is indicated; however, it rarely results in graft salvage. (See Schwartz 11th ed., p. 373.)
Answer: A
One of the most devastating postoperative complications in kidney recipients is graft thrombosis. It is rare, occurring in fewer than 1% of recipients. The recipient risk factors include a history of recipient hypercoagulopathy and severe peripheral vascular disease; donor-related risk factors include the use of en bloc or pediatric donor kidneys, procurement damage, technical factors such as intimal dissection or tor­sion of vessels, and hyperacute rejection. Graft thrombosis usually occurs within the first several days posttransplant. Acute cessation of urine output in recipients with brittle post­transplant diuresis and the sudden onset of hematuria or graft pain should arouse suspicion of graft thrombosis. Doppler ultrasound may help confirm the diagnosis. In cases of graft thrombosis, an urgent thrombectomy is indicated; however, it rarely results in graft salvage. (See Schwartz 11th ed., p. 373.)
CHAPTER 11
Transplantation
16. The most common causes of graft loss include: A. Recipient death. B. Acute rejection. C. Surgical technique. D. Postoperative infection.
17. After completion of the vascular anastomoses, drainage of the transplanted pancreas is accomplished by anasto­mosis to: A. Right colon. B. Left colon. C. Duodenum. D. Bladder or small bowel.
Answer: A
Currently, the most common cause of graft loss is recipi­ent death (usually from cardiovascular causes) with a func­tioning graft. The second most common cause is chronic allograft nephropathy; characterized by a slow, unrelenting deterioration of graft function, it likely has multiple causes (both immunologic and nonimmunologic). The graft failure rate due to complications related to surgical technique has remained at about 1% to 2% (See Schwartz 11th ed., p. 374.)
Answer: D
Over the years, different surgical techniques have been described for (a) the management of exocrine pancreatic secretions and (b) the type of venous drainage. For the secre­tions, the two most common techniques are drainage of the duodenal segment to the bladder (bladder drainage) or to the small bowel (enteric drainage) (Figs. 11-2 and 11-3). For venous drainage, systemic venous drainage is preferred over portal venous drainage. (See Schwartz 11th ed., p. 375, Figures 11-12 and 11-14.)
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CHAPTER 11
Transplantation
FIG. 11-2. Whole-organ transplant with systemic vein and
bladder exocrine drainage.
FIG. 11-3. Segmental transplant with systemic vein and bladder
exocrine drainage. The donor splenic artery and splenic vein are anastomosed end-to-side to the recipient’s external iliac artery and vein. The splenic artery anastomosis is lateral and proximal to the splenic vein anastomosis. A two-layer ductocystostomy is constructed.
18. Which of the following is TRUE about islet cell transplants? A. Involve anastomosis of an artery and vein of a seg-
ment of pancreas.
B. Islet allotransplants can prevent diabetes in patients
who require pancreatectomy.
C. Single donor islet cell transplants do not require
immunosuppression because they are injected in the portal vein.
D. It has been shown to reverse diabetes in >90% of
recipients.
Answer: B
Until recently, attempts to extend those trailblazing findings of clinical islet auto transplants to clinical islet allotransplants in patients with type 1 diabetes met with generally very poor success. For example, in 1995, a report of the International Islet Transplant Registry indicated that of 270 recipients, only 5% were insulin-independent at 1 year posttransplant.
In 2000, Shapiro and colleagues reported the results of the Edmonton protocol, which enabled consistent diabetes reversal and short-term (<1 year) insulin independence. The Edmonton protocol prescribed transplanting a large number of freshly isolated islets (>10,000 islet equivalents per kilo­gram body weight, typically requiring the use of two to four pancreases) with a specialized “islet-sparing,” steroid-free
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19. The most common diagnosis leading to heart transplant is: A. COPD. B. Congenital heart disease. C. Ischemic dilated cardiomyopathy. D. Idiopathic dilated cardiomyopathy.
20. The best method for monitoring the development of acute rejection in a patient after cardiac transplantation is: A. Dipyrimidole thallium study. B. Electrocardiogram. C. Endomyocardial biopsy. D. Echocardiography (ultrasound of heart).
immunosuppressive protocol consisting of low-dose tacroli­mus, sirolimus, and IL-2 receptor antibody induction. Those results were replicated at other experienced transplant cen­ters, but the rates of long-term (>5 year) insulin indepen­dence remained poor, well below those of whole-pancreas transplants. Still, despite the low rates of long-term insulin independence, most islet recipients were C-peptide positive and retained hypoglycemia awareness, indicating residual islet function and benefit. In fact, at 9 years posttransplant, 15% remained insulin-independent, and 73% had hypogly­cemia awareness and corrected hemoglobin Aic levels. (See Schwartz 11th ed., p. 378.)
Answer: C
The most common diagnosis leading to a heart transplant is ischemic dilated cardiomyopathy, which stems from coronary artery disease, followed by idiopathic dilated myopathy and congenital heart disease. About 3000 patients are added to the waiting list each year. (See Schwartz 11th ed., p. 389.)
Answer: C
The goal of immunosuppression is to prevent rejection, which is assessed by immunosuppressive levels and, early on, by endomyocardial biopsy. Both T-cell–mediated (cellu­lar) and B-cell–mediated (antibody-mediated) rejection are monitored. Most of the immunosuppression used is aimed at T-cells; however, if the recipient has many preformed anti­bodies or develops donor-specific antibodies, other strategies (such as plasmapheresis or rituximab) are used to reduce the antibody load. Immunosuppressive regimens can vary by cen­ter, but most often consist of three categories of medications: a calcineurin inhibitor (usually tacrolimus or cyclosporine), an antiproliferative agent (mycophenolate mofetil [MMF] or azathioprine [AZA]), and a corticosteroid (prednisone). Other immunosuppressive agents can be used, depending on the needs of individual recipients. (See Schwartz 11th ed., p. 390.)
CHAPTER 11
Transplantation
21. What is not a contraindication to liver transplantation? A. Chronic cardiac failure B. Stage 4 malignancy C. Refractory alcoholism D. Age > 70
22. Which of the following patients with hepatic failure ben­efit from liver transplantation? A. Model for End-Stage Liver Disease (MELD) > 18 B. All patients with MELD < 18 C. MELD 15–18 if they have significant morbidity from
cirrhosis
D. A and C only
Answer: D
In general, contraindications to a liver transplant include insufficient cardiopulmonary reserve, uncontrolled malig­nancy or infection, and refractory noncompliance. Older age is only a relative contraindication: carefully selected recipi­ents age >70 years can achieve satisfactory outcomes. (See Schwartz 11th ed., p. 382.)
Answer: D
The MELD was originally developed to assess risk for tran­sjugular intrahepatic portosystemic shunt (TIPS) placement. Later analysis revealed it to be an excellent model to predict survival among patients with cirrhosis, especially those on the waiting list for a liver transplant. In 2002, liver graft allo­cation was restructured to be based on the MELD score.
Although the historic indication for a liver transplant is decompensated cirrhosis, a landmark analysis comparing waiting list mortality with posttransplant mortality estab­lished that a minimum MELD score of 18 is necessary to have a survival benefit posttransplant. A MELD score between 15 and 18 does not confer a survival advantage, but a transplant may be justified if the patient has significant morbidity from cirrhosis. (See Schwartz 11th ed., p. 381.)
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CHAPTER 12
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Patient Safety
1. High reliability organization theory suggests that: A. Eliminating problematic individuals improves orga-
nizational reliability.
B. Strict reporting hierarchy and rules are key to success
at decreasing error rates. C. Low error rates are not possible in large organizations. D. Highly reliable organizations have friendly, coopera-
tive, resilient staffs where creativity and open rela-
tionships are encouraged.
2. Causes of death in the United States from the highest to the lowest: A. Heart Disease – Cancer – COPD – Medical Errors B. Cancer – Heart Disease – Medical Errors – Suicide C. Cancer – COPD – Heart Disease – Motor Vehicles D. Heart Disease – Cancer – Medical Errors – COPD
Answer: D
High reliability organization theory suggests that proper oversight of people, processes, and technology can handle complex and hazardous activities and keep error rates accept­ably low. Studies of multiple high reliability organizations show that they share the following common characteristics:
• People are supportive of one another.
• People trust one another.
• People have friendly, open relationships emphasizing
credibility and attentiveness.
• The work environment is resilient and emphasizes cre­ativity and goal achievement, providing strong feelings of credibility and personal trust.
Developing these characteristics is an important step toward achieving a low error rate in any organization. (See Schwartz 11th ed., p. 399.)
Answer: D
The most commonly cited report on the incidence of deaths due to medical error, the 1999 Institute of Medicine (IOM) report, describes an incidence of 44,000 to 98,000 deaths annually. However, this estimate by the IOM was not based on primary research conducted by the IOM; rather, it was based on two older studies conducted in 1984 and 1992. Both studies were small and limited. In 2013, after compiling more recent evidence from multiple sources, James estimated an incidence range of 210,000 to 400,000 deaths a year associ­ated with medical errors among hospital patients. Any point estimate in this range would rank the problem of dying from “medical care gone wrong” as the third leading cause of death in the United States. In caring for patients and considering the risks of tests and procedures done for borderline indications, it is important to consider the magnitude of the problem of patients dying from the care they receive rather than from the disease or injury that brought them to care. (See Schwartz 11th ed., p. 398.)
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