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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
CHAPTER 11
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:
CHAPTER 11
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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