A stroke volume-based fluid resuscitation protocol decreases vasopressor support and may increase organ yield in brain-dead donors

Outcomes of kidneys used for transplantation: an analysis of survival and function

Introduction

Kidney transplant recipients expect to survive the procedure with sufficient renal function for reliable dialysis freedom.

Methods

Transplant outcomes (survival and estimated renal function) were assessed after live and deceased donor transplantation from the US national database. Outcomes were stratified by age (donor and recipient) and donor type.

Results

Aggregate recipient outcomes were better transplanting living vs deceased donated kidneys. However, when stratified by the one-year renal function (within KDIGO CKD stage stratifications), surviving recipients had clinically similar dialysis-freedom, irrespective of donor type or age. The major outcome differences for recipients of age-stratified live and deceased kidneys was 1) the increasing frequency of one-year graft failures and 2) the increasing likelihood of severely limited renal function (CKD 4/5) with advancing donor age. Over 30% of recipients of deceased kidneys >65 years had either one-year graft failure or severely limited renal function contrasted to less than 15% of recipients of live kidneys aged >65 years.

Conclusions

Evolving techniques to reduce adverse events after urgent vs elective procedures, plus improved transplant outcome predictability with increased-age deceased donor kidneys using advanced predictive analytics (using age-stratified live kidney transplantation outcomes as a relevant reference point) should facilitate similar kidney transplant outcomes, irrespective of donor type.

Clinical outcomes of a prospective randomized comparison of bioreactance monitoring versus pulse-contour analysis in a stroke-volume based goal-directed fluid resuscitation protocol in brain-dead organ donors

Eighty percent of brain-dead (BD) organ donors develop hypotension and are frequently hypovolemic. Fluid resuscitation in a BD donor is controversial. We have previously published our 4-h goal-directed stroke volume (SV)-based fluid resuscitation protocol which significantly decreased time on vasopressors and increased transplanting four or more organs. The SV was measured by pulse-contour analysis (PCA) or an esophageal doppler monitor, both of which are invasive. Thoracic bioreactance (BR) is a non-invasive portable technology that measures SV but has not been studied in BD donors. We performed a randomized prospective comparative study of BR versus PCA technology in our fluid resuscitation protocol in BD donors. Eighty-four donors (53.1%) were randomized to BR and 74 donors to PCA (46.8%). The two groups were well matched based on 24 demographic, social, and initial laboratory factors, without any significant differences between them. There was no difference in the intravenous fluid infused over the 4-h study period [BR 2271 ± 823 vs. PCA 2230 ± 962 mL; p = .77]. There was no difference in the time to wean off vasopressors [BR 108.8 ± 61.8 vs. PCA 150.0 ± 68 min p = .07], nor in the number of donors off vasopressors at the end of the protocol [BR 16 (28.6%) vs. PCA 15 (29.4%); p = .92]. There was no difference in the total number of organs transplanted per donor [BR 3.25 ± 1.77 vs. PCA 3.22 ± 1.75; p = .90], nor in any individual organ transplanted. BR was equivalent to PCA in clinical outcomes and provides a simple, non-invasive, portable technology to monitor fluid resuscitation in organ donors.

The 20-year paradigm shift toward organ recovery centers: 2500 donors at Mid-America Transplant and broader adoption across the United States

On March 1, 2001, Mid-America Transplant, the organ procurement organization (OPO) located in St Louis, Missouri, performed the first organ recovery of a brain-dead donor in a hospital-independent, free-standing, organ recovery center (ORC), with successful transplantation of a liver. This was the inception of a paradigm shift in donor management and organ procurement, moving away from the traditional method of using the donor hospital. In the last 20 years, many advances have occurred in the ORC. Brain-dead donors are moved within hours of authorization to fully equipped intensive care units. Some ORCs are equipped with computed tomography scanners, portable radiography, laboratory facilities, bronchoscopy, and a cardiac catheterization laboratory. ORCs have dedicated surgical suites, and operating time is frequently during the day and is rarely delayed. Donor management in an ORC is more consistent, efficient, and effective than that in a donor hospital, and studies have demonstrated increased organ yield. Multiple studies have demonstrated a cost benefit of an ORC as well as providing an ideal environment for donor research studies. Currently, there are 24 of 57 OPOs that are using an independent or hospital-based ORC to manage their donors. We review the history and describe the current state of ORCs.

The benefits of initiating continuous renal replacement therapy after brain death in organ donors with oligoanuric acute kidney injury

Acute kidney injury (AKI) in deceased organ donors is increasing due to the escalation in anoxic brain-deaths. The management of an organ donor with oligoanuric AKI is frequently curtailed due to hemodynamic and electrolyte instability. Although continuous renal replacement therapy (CRRT) corrects the effects of AKI, it is rarely started after the diagnosis of brain-death (BD). Since 2017, we have initiated CRRT in organ donors with oligoanuric AKI to allow more time to stabilize the donor and improve the function of the thoracic organs. We now report our experience with the first 27 donors with oligoanuric AKI that received CRRT after the diagnosis of BD, with organs transplanted as the primary outcome. The average duration of CRRT was 30.1±14.4 hours and the mean ultrafiltration volume was 5,141±4,272 milliliters. The time from BD declaration to cross clamp was significantly longer in the CRRT group versus a historical cohort with oligoanuric AKI that was not dialyzed (62.8±18.3 vs 37.1±14.9 hours; p<0.01) The mean number of total organs transplanted per donor in the CRRT group was greater than the historical cohort, 2.9±1.7 vs 1.4±0.6 (p = 0.<01), respectively. The mean number of thoracic organs transplanted per donor also increased between the two groups, 1.4±1.2 vs 0.6±0.9 (p = 0.02). Thirty-seven percent of the kidneys were successfully transplanted with a mean serum creatinine of 1.4 mg/dL at six months. We suggest that OPOs consider starting CRRT in organ donors with oligoanuric AKI to possibly increase the number of organs transplanted. This article is protected by copyright. All rights reserved.

Specialized Donor Care Facility Model and Advances in Management of Thoracic Organ Donors

BACKGROUND

Donor hearts and lungs are more susceptible to the inflammatory physiologic changes that occur after brain death. Prior investigations have shown that protocolized management of potential organ donors can rehabilitate donor organs that are initially deemed unacceptable. In this review we discuss advances in donor management models with particular attention to the specialized donor care facility model. In addition we review specific strategies to optimize donor thoracic organs and improve organ yield in thoracic transplantation.

METHODS

We performed a literature review by searching the PubMed database for medical subject heading terms associated with organ donor management models. We also communicated with our local organ procurement organization to gather published and unpublished information first-hand.

RESULTS

The specialized donor care facility model has been shown to improve the efficiency of organ donor management and procurement while reducing costs and minimizing travel and its associated risks. Lung protective ventilation, recruitment of atelectatic lung, and hormone therapy (eg, glucocorticoids and triiodothyronine/thyroxine) are associated with improved lung utilization rates. Stroke volume-based resuscitation is associated with improved heart utilization rates, whereas studies evaluating hormone therapy (eg, glucocorticoids and triiodothyronine/thyroxine) have shown variable results.

CONCLUSIONS

Lack of high-quality prospective evidence results in conflicting practices across organ procurement organizations, and best practices remain controversial. Future studies should focus on prospective, randomized investigations to evaluate donor management strategies. The specialized donor care facility model fosters a collaborative environment that encourages academic inquiry and is an ideal setting for these investigations.

Centralized Organ Recovery and Reconditioning Centers

An increased focus on improving efficiency and decreasing costs has resulted in alternative models of donor management and organ recovery. The specialized donor care facility model provides highly efficient and cost-effective donor care at a free-standing facility, resulting in improved organ yield, shorter ischemic times, decreased travel, and fewer nighttime operations. Ex vivo lung perfusion (EVLP) improves utilization of extended criteria donor lungs, and centralized EVLP facilities have the potential to increase transplant volumes for smaller transplant programs in specified geographic regions. These alternative models are increasingly being used in the United States to improve waitlist mortality and combat the ongoing donor organ shortage.

Ventilation in the prone position improves oxygenation and results in more lungs being transplanted from organ donors with hypoxemia and atelectasis

BACKGROUND

Hypoxemia is the most common barrier to lungs being transplanted from eligible organ donors who are brain dead (BD). Atelectasis is the principal reversible contributing factor to hypoxemia after brain death. We evaluated prospectively whether ventilation in the prone position in donors who are BD would reverse atelectasis, improve oxygenation, and result in more lungs being transplanted.

METHODS

Organ donors managed at the recovery center of 1 organ procurement organization over a 2-year period who exhibited hypoxemia (partial pressure of arterial oxygen [PaO₂]/fraction of inspired oxygen of <300 mm Hg) and had evidence of atelectasis were ventilated in the prone position for 12 hours or longer during donor management. A subset underwent computed tomography (CT) imaging to quantify the degree of atelectasis before and after prone positioning. Outcomes were compared with those of a control group with hypoxemia and atelectasis managed similarly but in the supine position in the previous 2 years.

RESULTS

A total of 40 lung-eligible donors who were BD with hypoxemia and atelectasis were managed in a prone position and compared with 79 donors in supine position. Baseline PaO₂ was similar between the prone and the supine groups (194 ± 78 vs 177 ± 77 mm Hg, p = 0.26) but increased more in the prone group at 4 hours (by 113 vs 54 mm Hg, p = 0.001) and remained 74-mm Hg higher at 12 hours (340 vs 266 mm Hg, p = 0.0006). CT-graded atelectasis was significantly reduced after ventilation in the prone position but persisted in the supine group (p = 0.001). Final PaO₂ was not significantly higher (344 vs 306, p = 0.12), but lungs were more often transplanted in the prone group (45% vs 24%, p = 0.03).

CONCLUSIONS

Ventilation in the prone position reverses atelectasis and rapidly and sustainably improves oxygenation in organ donors who are BD with hypoxemia. This effect appears to translate into more lungs being transplanted.