Donor Characteristics in 1,000 Consecutive Simultaneous Pancreas-Kidney Transplants

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Donor Characteristics in
1,000 Consecutive Simultaneous
Pancreas-Kidney Transplants
Hans W. Sollinger, Jon S. Odorico,
Glen E. Leverson, Barbara J. Voss,
and Anthony M. D’Alessandro
Department of Surgery,
Division of Transplantation,
University of Wisconsin,
U.S.A.
1. Introduction
In 2003, Krieger et al. from our group published a manuscript which investigated the use of
pancreas grafts for transplantation in different UNOS regions in the United States (1). It was
reported that the utilization of pancreata showed a wide variation depending on the region.
To approach some degree of standardization, we calculated the ratio of pancreata used for
transplantation with the number of livers procured and transplanted. Using the data from
our own institution, we had experienced that at least 70% of liver donors should provide
acceptable pancreas grafts. The results of the study, however, demonstrated that in some
regions, less than 20% of liver donors yielded pancreas grafts. Ensuing discussion revealed
that the lack of established criteria to predict the outcome of pancreas transplantation based
on available donor criteria was one of the reasons many centers, in particular less
experienced programs, were hesitant to accept donors other than those expected to provide
excellent pancreas grafts, and therefore, outcomes. Since then, few publications have
addressed the correlation between available donor criteria and short- or long-term
outcomes. One single center report analyzing outcomes in 61 simultaneous pancreas-kidney
transplants (SPK) was published in 1995 by Douzdjian et al. (2), and a multi-center
European report by Vinkers et al. (3) attempted to establish a donor quality score. During
the preparation of this manuscript, the online version of a large-scale analysis using data
from the Scientific Registry of Transplant Recipients (SRTR) in 9,401 transplants from 2000
to 2006 became available for review (4).
The purpose of this manuscript is to report the donor characteristics in 1,000 consecutively
performed SPK transplants at a single center. Pancreas-kidney retrieval and donor
management, as well as donor evaluation, were performed by the same organ procurement
organization (UW OPO). Retrieval was performed by surgeons trained at our institution.
Using only donor data easily available to OPO personnel and surgeons, we attempt here to
provide straightforward guidelines regarding the acceptability of pancreas grafts. A unique
feature of this study is the fact that long-term follow up is available up to 22 years.

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2. Materials and methods
Between December 18, 1985 and December 3, 2007, 1,000 consecutive donor
pancreatectomies were performed by the members of the University of Wisconsin transplant
team and the University of Wisconsin OPO. In general, the retrieval team consisted of a
transplant surgeon or a Board-certified/eligible surgeon, a transplant fellow and a
procurement specialist. Over the 20-year interval, only a small number of surgeons and
transplant specialists—all trained at our institution—were involved, keeping the surgical
approach standardized. The principles of the donor operation have been previously
described in detail (5). Our routine consisted of in situ flushing with UW solution (ViaSpan®,
Bristol-Myers Squibb, Garden City, NY), after dissection of the pancreas and liver. A point
was made not to exceed 2 liters of flush solution. The mesenteric vessels were always
ligated. Donor demographics are shown in Table 1. Donor management was conducted by
the intensive care staff of the referring hospital in consultation with OPO personnel. No
OPO personnel was on site until the retrieval procedure. During organ retrieval, generous
use of colloids was used to reduce pancreatic edema. All organs were stored in UW solution.
Surgical implant technique, recipient management and immunosuppressive therapy have
been previously described (6). It is of note that we never used any systemic anticoagulation
in the recipients post-transplant.
Data for analysis was obtained from the UW OPO records and transferred into the UW
Transplant database.
Histocompatibility testing was performed prior to all transplants, but no attempt was made
to match donor and recipient as closely as possible. The only absolute requirement was a
negative T-cell crossmatch using the NIH technique.
Statistical Analysis
For statistical analysis, continuous variables were summarized by reporting mean and
standard deviation, and categorical variables were summarized by reporting percentages.
Event rates were estimated using methods of Kaplan and Meier and compared between
groups using a log rank test. P<0.05 was considered significant. All analyses were
performed using SAS statistical software (SAS Institute, Inc., Cary, NC).
3. Results
For reporting purposes, the highest value among donor laboratory values was chosen for
our calculations. BMI was determined by weight at the time of admission. Vasopressor use
was defined as the use of any vasopressor at any time from the patient’s admission to the
time of the retrieval procedure. As expected, long-term outcomes for pancreas graft survival
correlated with donor age (Figure 1). Donor age as previously reported by others appears to
be a major risk factor. As previously reported by Fernandez, et al., young donors do
extremely well despite higher technical difficulties (7). The youngest SPK donor in our
experience was three years of age. These grafts should be placed into smaller recipients. BMI
also had a significant correlation with inferior long-term outcomes (Figure 2). Obese donors,
even in the younger age groups, have pancreata which are infiltrated by fatty tissue and
respond poorly to preservation. In addition, fat necrosis after transplantation may lead to
intra-abdominal fluid collections and subsequent abscess formation. Nevertheless, on

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occasion a donor with a high BMI may have a normal-appearing pancreas which can be
safely used for transplantation.
Laboratory determinations such as amylase and lipase (p>0.08) have not shown any
correlation with outcomes, as previously reported by Odorico et al. in a smaller cohort (8).
In addition, maximum glucose levels have no predictive value. Glucose values often reflect
the resuscitation effort and may be skewed by the co-administration of other drugs such as
corticosteroids. In an unpublished study by our group, determination of HbA1C in
100 consecutive donors did not elicit a single abnormal value which would allow the
conclusion that medical history is sufficient to rule out diabetes or pre-diabetes. At the start
of our program, we were hesitant to retrieve pancreata from donors with abdominal trauma
and prior surgery, which frequently included splenectomy. With growing experience, we
have learned to use these donors after careful inspection of the pancreas and duodenum.
There is no difference in long-term outcomes (p=0.6585). Pancreatic grafts from young
trauma victims are frequently very edematous, but return to normal texture after
preservation in UW solution. Furthermore, the use of vasopressors is not associated with
inferior long-term survival (p=0.9196).
4. Discussion
Data published by UNOS/SRTR reveal that the number of SPKs performed has not
increased despite an increase in the number of potential pancreas donors by an average of
482 per year since 2003 (4). Most of these consented organs have not been recovered. The
non-recovery rate among pancreata is at an all-time high of about 72% (4). Among the
possible reasons are a) an older donor population; b) allocation criteria which lists kidney
recipients and SPK recipients on the same list; and c) surgeons’ fears of achieving inferior
results, which in turn might result in termination of insurance coverage for the program.
These fears are heightened by the fact that few objective criteria for donor selection exist. In
1998, Odorico et al. from our group analyzed donor factors affecting outcome after pancreas
transplantation in 240 recipients (8). The relevant conclusions were that pancreata from
donors >45 years of age are associated with a higher failure rate. This finding was consistent
with the observations of Gruessner et al. reported in 1994 (9). Odorico et al. also conclude
that serum amylase and glucose did not correlate with graft failure (8). Furthermore, in a
small series of donation after cardiac death (DCD) donors, no difference in short-term
outcomes was noted. Douzdjian et al. analyzed their single-center experience in 61 SPKs
and found that duration of brain death before procurement, length of donor admission and
donor age were the major factors associated with inferior outcomes (2). In accordance with
our observations, serum glucose and serum amylase did not correlate with outcomes.
Recently, the online version of a manuscript by Axelrod et al. was available for review (10).
SRTR data from over 9,401 pancreas donors were used to develop a Pancreas Donor Risk
Index (PDRI). As pointed out by Krieger (1), the authors emphasize that pancreas utilization
shows great regional variation in the United States and that donor selection is widely used
as a key factor to successful pancreatic transplantation. The study is based on retrospective
data from multiple centers using a variety of procurement techniques.
The uniqueness of this manuscript is that universal procurement and retrieval techniques
were used and that the implant team primarily consisted only of a small group of uniformly
trained surgeons. Our message is that the donor surgeon should not be discouraged from

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exploring a donor with high amylase, lipase and glucose levels. Also, the use of
vasopressors should not be a reason to decline. Data by Bellingham et al. demonstrate that
the same criteria apply in DCD pancreas donors (11).
Using these simplified criteria (age and BMI) for evaluating prospective pancreas donors,
together with visual inspection of the graft, suitable pancreas grafts can be chosen to achieve
excellent long-term functional outcomes (12). Adequately trained OPO personnel and
procurement surgeons will be able to use these simple guidelines in order to maximize
potential utilization of pancreas donors.







Mean (range)
Age (years) 29 (3-60)
Weight (kg) 72 (15-156)
Amylase (U/L) 99 (2-2,002)
Glucose (mg/dL) 189 (6 – 824)
Pancreas cold storage time (hours) 15 (0-43)
N (%)
Gender:
Male
Female

604 (62.5%)
363 (37.5%)
Race:
Caucasian
African-American
Asian
Native American

944 (97.5%)
16 (1.7%)
6 (6.2%)
1 (0.1%)






Table 1. Donor demographics

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Fig. 1. Age and pancreas transplant outcome


Fig. 2. BMI and pancreas transplant outcome

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5. References
[1] Krieger NR, Odorico JS, Heisey DM, et al. Underutilization of pancreas donors.
Transplantation 2003;75:1271-6.
[2] Douzdjian V, Gugliuzza KG, Fish JC. Multivariate analysis of donor and recipient risk
factors for renal and pancreas allograft failure after pancreas-kidney
transplantation. Transplant Proc 1995;27:3128-9.
[3] Vinkers MT, Rahmel AO, Slot MC, Smits JM, Schareck WD. How to recognize a suitable
pancreas donor: a Eurotransplant study of preprocurement factors. Transplant Proc
2008;40:1275-8.
[4] Scientific Registry of Transplant Recipients [Internet]. www.ustransplant.org
[5] Sollinger HW, Odorico JS, Knechtle SJ, D’Alessandro AM, Kalayoglu M, Pirsch JD.
Experience with 500 simultaneous pancreas-kidney transplants. Ann Surg
1998;228:284-96
[6] Sollinger HW, Odorico JS, Becker YT, D’Alessandro AM, Pirsch JD. One thousand
consecutive simultaneous pancreas-kidney transplants at a single center with 22-
year follow-up. Ann Surg 2009;250:618-30.
[7] Fernandez LA, Turgeon NA, Odorico JS, et al. Superior long-term results of
simultaneous pancreas-kidney transplantation from pediatric donors. Am J
Transplant 2004;4:2093-101.
[8] Odorico JS, Heisey DM, Voss BJ, et al. Donor factors affecting outcome after pancreas
transplantation. Transplant Proc 1998;30:276-7.
[9] Gruessner RW, Troppmann C, Barrou B, et al. Assessment of donor and recipient risk
factors on pancreas transplant outcome. Transplant Proc 1994;26:437.
[10] Axelrod DA, Sung RS, Meyer KH, Wolfe RA, Kaufman DB. Systematic Evaluation of
Pancreas Allograft Quality, Outcomes and Geographic Variation in Utilization. Am
J Transplant (in press).
[11] Bellingham J, Goodman J, Leverson G, et al. Ten-year outcomes of simultaneous
pancreas-kidney transplantation from donation after cardiac death. Am J
Transplant 2008;8(suppl. 2):201 (published abstract).
[12] Sollinger HW, Odorico JS, Becker YT, D’Alessandro AM, Pirsch JD. One thousand
consecutive simultaneous pancreas-kidney transplants at a single center with 22-
year follow-up. Ann Surg 2009;250:618-30.