Transcript Improving Outcomes in DCD Renal Transplantation

Improving Outcomes in DCD
Renal Transplantation
Reference: Hoogland ERP, Snoeijs MGJ, van
Heurn LWE. DCD kidney transplantation:
Results and measures to improve outcome.
Curr Opin Organ Transplant. 2010;15:177–182.
• In end-stage renal disease (ESRD), renal transplantation is the
treatment of choice; however, shortage of organ donors creates a
major set back.
• The liberal use of kidneys from donors after cardiac death (DCD)
holds the potential to increase the number of organ donors by 2.5–4
times, which is sufficient to reduce or even eliminate the waiting lists
for kidney transplantation.
• Unlike the donation after brain death (DBD), organs from DCD donors
inevitably sustain a period of warm ischemia from circulatory arrest
until initiation of organ preservation, which causes ischemic acute
kidney injury, which results in an increased incidence of delayed graft
function (DGF) and primary nonfunction (PNF) as compared with
kidney transplantation from conventional brain-dead donors.
• These early complications associated with DCD kidney
transplantation are the reason for the disinclination of using these
kidneys for transplantation.
• At the first international workshop on DCD donation in
Maastricht, 1995, four categories were discussed and
accepted to categorize DCD kidneys according to their
period of warm ischemia (see Table 1).
• The longest warm ischemia time occurs in category I
donors, whereas categories III and IV have potentially
the shortest time.
• Categories I and II represent ‘uncontrolled’ donors, as
these donors are dead on arrival or undergo
unsuccessful resuscitation, respectively. ‘Controlled’
donors of the categories III and IV are from the
intensive care unit when withdrawal of medical
treatment is planned or cardiac arrest in brain-dead
patients occurs.
Outcomes of Kidney Transplantation
from DCD
• Results from comparative studies involving DCD and DBD kidney
transplantation have shown a relatively high incidence of PNF in DCD
kidneys, which has been attributed to the ischemic injury suffered before
organ recovery.
• The incidence of PNF could be as high as 15–25%, based on the threshold
to discard or to accept DCD kidneys for transplantation.
• A method to improve the results of DCD kidney transplantation without
changing the selection criteria is by better recipient management.
• Careful fluid management of the recipient with intraoperative systolic
blood pressure above 110 mmHg and central venous pressure above 6 cm
H2O reduces the probability of PNF 3–10 times.
• Recently (2009), the Leicester group reported that the results of
functioning DCD kidneys were similar to DBD kidneys after a follow-up
period ranging from 5 to 15 years for mainly uncontrolled (Maastricht
category II) kidneys, despite higher rates of DGF.
• This is in confirmation of the results that reveal the long-term outcome
(follow-up up to 25 years) of viable DCD kidneys that was equivalent to
grafts recovered from brain-dead donors.
Standard Preservation Techniques for
DCD Renal Transplantation
• In several centers, in situ preservation (ISP) is the method of choice for
uncontrolled, Maastricht categories I and II, DCD donors.
• It is an indispensable technique that can provide the opportunity to meet
legal and logistical requirements for organ recovery without excessive
warm ischemia times, besides the transplantation procedures can be
initiated prior to consent for organ donation depending on the legal
opportunities.
• In Maastricht category III donors, withdrawal of life support usually takes
place in the ICU.
• The patient after cardiac arrest and the obligatory no-touch period, is
transported to the operating room, after which rapid laparotomy is
performed with direct cannulation of the aorta.
• The warm ischemia time with this technique can be limited to 20 min.
• In order to keep the transportation time to a minimum, a short distance
between the ICU and the operating room has to be maintained.
New Developments in Donor
Management Before and During Organ
Preservation
• Cardiopulmonary resuscitation (CPR) can be used while
preservation measures are taken in category II donors to
reduce ischemic damage to the kidney of a potential donor,
while maintaining an adequate circulation after cardiac
arrest and a no-touch period of 5 min.
• Data indicate that despite CPR, donor kidneys suffer
extensive warm ischemic injury.
• In order to improve CPR by performing consistent rates and
depths of chest compressions, a variety of automated chest
compression devices have been studied.
• Their reports describe improved hemodynamic effects and
better coronary perfusion with increased peak aortic
pressure over manual CPR.
New Developments in Donor
Management Before and During Organ
Preservation
• Chest compression devices, such as the AutoPulse (ZOLL
Circulation, Sunnyvale, California) (see Fig. 2), are used to
preserve DCD donor organs from cardiac arrest until in situ
cooling using a double-balloon triple-lumen (DBTL)
catheter.
• Moreover, extracorporeal membrane oxygenation (ECMO)
has the potential to improve organ quality by providing
normal tissue perfusion after cardiac death.
• Since its introduction in the early 1970, it has become a
standard therapy to provide temporary circulatory support
and systemic oxygenation for patients with reversible
cardiac or respiratory failure that cannot be supported with
conventional mechanical ventilation.
Fig. 2: Chest compression device: AutoPulse
Results of in-situ Preservation and
Direct Cannulation of the Aorta
• In controlled DCD donors, rapid laparotomy and
direct cannulation of the aorta has lead to a
significantly superior graft survival compared to
DCD donor kidneys that are preserved in situ.
• These donors have shorter warm ischemia times
and lower rates of discard.
• Therefore, rapid laparotomy and direct aortic
cannulation is considered preferable above in situ
perfusion using DBTL catheters as the method for
initiation of organ preservation in controlled DCD
donors.
Preservation and Assessment of
Kidneys after Recovery
• After successful organ recovery from DCD, kidneys are stored either on
melting ice or on a pulsatile cold perfusion machine, which may provide
a useful platform to assess the kidney function by several viability tests;
Subsequent to the assessment of acute ischemic injury, kidneys from old
donors can have chronic degenerative changes.
• The only proven predictor for graft function and survival among several
selection criteria is histological assessment of degenerative changes in
pretransplant kidney biopsies in donors aged ≥60 years.
• Preimplantation histological kidney damage is associated with
premature graft loss in older donors compared to donor age, kidney
function, kidney weight and perfusion parameters.
• As a result, histological assessment of renal biopsies is a clinically useful
tool to select kidneys from donors with satisfactory outcome, which is a
better approach than setting arbitrary age limits for kidney donation.
Conclusion
• The risk of DGF and PNF with DCD kidneys can be
reduced primarily by organ preservation using rapid
laparotomy and direct aortic cannulation for controlled
DCD donors and thereafter by reducing the warm
ischemia time using automated chest compression
devices and ECMO. In order to improve the treatment
of waitlisted dialysis patients, expansion of the donor
pool by using more uncontrolled donors supported
with ECMO is of paramount importance.
• Improving the quality of DCD kidneys with continued
and novel methods can expand the utilization of this
large pool of donor kidneys to its full potential.