Perfusion Strategies Research Articles

What are the minimal criteria of goal-directed perfusion (GDP) in adult cardiac surgery?

Introduction: Nowadays, many cardiac surgery teams are adopting the goal-directed perfusion (GDP) strategy in their practice to maintain optimal perfusion during cardiac surgeries and improve patient outcomes. Furthermore, it plays an indispensable role as a quality control tool to monitor both perfusionists’ practice and equipment (in addition to disposables used in the surgery. Objectives: To identify the role and the elements of GDP that facilitate better surgical outcomes. In addition, to compare between GDP and the traditional conventional perfusion strategy (CP) in terms of perfusion adequacy and surgical outcomes. Finally, to recognize challenges that may prevent the effective application of GDP and finding possible applicable solutions. Methods: A systematic literature review was conducted from three different databases PubMed, SpringerLink, and ScienceDirect. The selected studies were in English from the USA and Europe with a time frame starting from 2005. Results: The findings highlight the crucial role of the GDP strategy in protecting and preserving end-organ function after on-bypass cardiac surgery procedures. Furthermore, a clear understanding of the GDP implementation component and criteria was obtained. Alternatively, a satisfactory GDP level can be achieved by the optimal utilization of available resources. Discussion: Dismantling the GDP strategy into practically recognized components to ease the implementation at different levels of perfusion practice. Conclusion: The GDP approach involves the intensive monitoring of respiratory-related parameters to enhance surgical outcomes. The process includes blood preservation, optimal flow and intraoperative parameters management. Monitoring is the key element of GDP, which can be applied by using the sophisticated technology or the proper use of existing resources to develop protocols within the international guidelines and recommendations. Achieving an optimal perfusion requires concerted efforts of organizational, safety, and practical measurements.

Goal-directed perfusion to reduce acute kidney injury after pediatric cardiac surgery

Although the goal-directed perfusion (GDP) during cardiopulmonary bypass (CPB) has been discussed a lot in adult studies, no pediatric indexed oxygen delivery (DO2i) thresholds are universally accepted, and no pediatric randomized controlled trial (RCT) is reported until now. This study aimed to determine whether the GDP initiative (maintaining DO2i ≥ 360 mL/min/m2 during CPB) could reduce the incidence of acute kidney injury (AKI) after pediatric cardiac surgery and improve clinical outcomes. This single-center RCT enrolled 312 pediatric patients, who were randomized to receive either the GDP strategy or a conventional perfusion strategy during CPB. The primary outcome was the rate of postoperative AKI. Secondary outcomes included major postoperative complications, all-cause mortality within 30 days and short-term clinical outcomes after surgery. AKI occured in 43 patients (28.1%) in the GDP group and in 65 patients (42.2%) in the control group (relative risk, 0.67; 95% confidence interval, 0.49-0.91; P = 0.010). In the subgroup analysis, The GDP group had a lower AKI rate compared with the control group among patients with age less than 1 year, with nadir temperature greater than 32°C and nadir hemoglobin less than 8 g/L during CPB, with preoperative cyanosis, and with CPB duration from 60 to 120 minutes. The GDP strategy aimed at maintaining DO2i ≥ 360 mL/min/m2 during CPB is effective in reducing the risk of AKI after pediatric cardiac surgery.

Short-term outcomes of mild (≥30 ℃) vs. moderate hypothermic circulatory arrest in aortic arch surgery.

Hypothermia and antegrade cerebral perfusion (ACP) strategies in open aortic arch surgery (AAS) have improved significantly. The significance of the gradual temperature rise to mild hypothermia is quite apparent, however, its safety remains a challenge. Therefore, our objective was to explore the safety and efficacy of mild hypothermic circulatory arrest (Mi-HCA, ≥30 ℃). This retrospective cohort study enrolled in a total of 372 patients, and was performed at the Beijing Anzhen Hospital between January 2017 and November 2022. Among the 372 patients, 81 received AAS at ≥30 ℃, and the remaining 291 received the same at 22-29.9 ℃. Most acute type A aortic dissection (ATAAD) patients received total arch replacement (TAR) and frozen elephant trunk (FET) operation. Mi-HCA patients exhibited strongly augmented systemic temperature (26.19±1.63 vs. 31.40±0.79 ℃, P<0.01). The surgical, cardiopulmonary bypass (CPB), cross-clamp, circulatory arrest, and ACP durations were drastically diminished among Mi-HCA patients (all P<0.01). Moreover, the major adverse events (MAEs) incidence of Mi-HCA patients was significantly decreased (25.43% vs. 14.81%, P<0.05). Simultaneously, the Mi-HCA strategy also exhibited enhanced protection of blood cells, as well as myocardial and hepatic function. Nevertheless, multivariate logistic regression analysis revealed that Mi-HCA strategy (≥30 ℃) was not a stand-alone risk factor for MAEs following AAS. The short-term outcomes and safety of Mi-HCA, in combination with ACP, in AAS are satisfactory. Additionally, relative to the traditional moderate hypothermic circulatory arrest (MHCA) approach, it can substantially decrease operation duration while improving patient clinical outcomes.

Current and Future Applications of Machine Perfusion and Other Dynamic Preservation Strategies in Liver Transplantation

Current and Future Applications of Machine Perfusion and Other Dynamic Preservation Strategies in Liver Transplantation

Evaluation of end-organ protection in newborns and infants after surgery of aortic arch hypoplasia: A prospective randomized study.

Surgical repair of aortic arch hypoplasia in children requires a "dry" surgical field with reliable end-organ protection. Perfusion strategies commonly involve deep hypothermic circulatory arrest (DHCA) and variations of the continuous perfusion techniques, such as selective antegrade cerebral perfusion (SACP) and full-flow perfusion with double aortic cannulation (DAC). We aimed to evaluate the end-organ protection in the surgery of aortic arch hypoplasia in newborns and infants using DHCA and DAC. 66 newborns and infants with aortic arch hypoplasia and biventricular anatomy were enrolled in this prospective study. Patients were randomly assigned into two groups according to the perfusion strategy - DHCA (n = 33); and DAC (n = 33). Primary endpoint: acute kidney injury (AKI), graded according to the KDIGO score. Secondary endpoints: neurological sequelae (pre- and postoperative MRI), in-hospital mortality. The lowest temperature was 32 (28; 34)°С in the DAC group and 23 (20; 25)°С in the DHCA group. The patients with DAC had lower incidence of AKI (6 patients (18.2%) versus 19 patients (57.6%); p = .017). In the multivariate analysis, the inotropic index at 48h was identified as a risk factor, increasing the risk of AKI by 4%. The DHCA group was associated with a 3.8-fold increase in the risk of AKI. There was no difference in hospital mortality between the DAC and DHCA groups (1 patient (3%) versus 3 patients (9.1%); p = .61). Neurological sequelae by MRI scan were observed in 18 patients (54.5%) in the DHCA group compared to 5 patients (15.15%) in the DAC group (p = .026). The only risk factor identified in the multivariate analysis for neurological lesions on MRI scan was the DHCA group, which increased the risk by 8.8 times. Surgical reconstruction of the aortic arch hypoplasia using the method of full-body perfusion reduces the incidence of neurological lesions and renal complications requiring renal replacement therapy compared with the deep hypothermic circulatory arrest in neonates and infants.

Establishment of cerebral perfusion in a rat model with extracorporeal life support.

Background: Extracorporeal life support echniques as an Adjunct to Advanced Cardiac Life Support is usually suitable for complex heart surgery such as cardiopulmonary bypass (CPB). Cerebral perfusion is a clinically feasible neuroprotective strategy; however, the lack of a reliable small animal model.Methods: Based on the rat model of ECLS we evaluate the effects of ECLS-CP using HE staining, Nissl staining, TUNEL staining and ELISA.Result: We found that ECLS combined with the cerebral perfusion model did not cause brain injury and immune inflammation. There was no difference between the two by a left carotid artery or right carotid artery CP.Conclusion: These experimental results can provide the experimental basis for selecting blood vessels for ECLS patients and clinical CP to offers a trustworthy animal model for future exploration of applying brain perfusion strategies during ECLS-CP.

Optimization of Hypothermic Protocols for Neurocognitive Preservation in Aortic Arch Surgery: A Literature Review.

Shifts from deep to moderate hypothermic circulatory arrest (HCA) in aortic arch surgery necessitate an examination of their differential impacts on neurocognitive functions, especially structured verbal memory, given its significance for patient recovery and quality of life. This study evaluates and synthesizes evidence on the effects of deep (≤20.0 °C), low-moderate (20.1-24.0 °C), and high-moderate (24.1-28.0 °C) hypothermic temperatures on structured verbal memory preservation and overall cognitive health in patients undergoing aortic arch surgery. We evaluated the latest literature from major medical databases such as PubMed and Scopus, focusing on research from 2020 to 2024, to gather comprehensive insights into the current landscape of temperature management during HCA. This comparative analysis highlights the viability of moderate hypothermia (20.1-28.0 °C), supported by recent trials and observational studies, as a method to achieve comparable neuroprotection with fewer complications than traditional deep hypothermia. Notably, low-moderate and high-moderate temperatures have been shown to support substantial survival rates, with impacts on structured verbal memory preservation that necessitate careful selection based on individual surgical risks and patient profiles. The findings advocate for a nuanced approach to selecting hypothermic protocols in aortic arch surgeries, emphasizing the importance of tailoring temperature management to optimize neurocognitive outcomes and patient recovery. This study fills a critical gap in the literature by providing evidence-based recommendations for temperature ranges during HCA, calling for ongoing updates to clinical guidelines and further research to refine these recommendations. The implications of temperature on survival rates, complications, and success rates underpin the necessity for evolving cardiopulmonary bypass techniques and cerebral perfusion strategies to enhance patient outcomes in complex cardiovascular procedures.

Impact of machine perfusion on transplant infectious diseases: New challenges and opportunities.

Preservation techniques that maintain the viability of an organ graft between retrieval from the donor and implantation into the recipient remain a critical aspect of solid organ transplantation. While traditionally preservation is accomplished with static cold storage, advances in ex vivo dynamic machine perfusion, both hypothermic and normothermic, have allowed for prolongation of organ viability and recovery of marginal organs effectively increasing the usable donor pool. However, the use of these novel machine perfusion technologies likely exposes the recipient to additional infectious risk either through clonal expansion of pathogens derived during organ recovery or de novo exogenous acquisition of pathogens while the organ remains on the machine perfusion circuit. There is a paucity of high-quality studies that have attempted to quantify infection risk, although it appears that prolonging the time on the machine perfusion circuit and normothermic parameters increases the risk of infection. Conversely, the use of ex vivo machine perfusion unlocks new opportunities to detect and treat donor-derived infections before implantation into the recipient. This review seeks to reveal how the use of ex vivo machine perfusion strategies may augment the risk of infection in the organ recipient as well as outline ways that this technology could be leveraged to enhance our ability to manage donor-derived infections.

Machine perfusion in transplantation surgery

The use of machine perfusion in solid organ transplantation has developed tremendously worldwide in recent years. Although the number of randomized controlled trials in the field of organ preservation is still limited, machine perfusion has been shown to be superior to static cold storage of donor organs. Various devices for clinical use with hypothermia or normothermia are already available for most organs. Whether and which perfusion strategy is superior to the others is the subject of current clinical research. This also applies to the further evaluation of possible synergistic effects in the sequential use of the various protocols. The common goal of all dynamic perfusion technologies is to optimize organ preservation between removal and transplantation. By testing the quality of marginal donor organs prior to transplantation, it should also be possible to use these organs without exposing the patient to increased risk. This can lead to a significant expansion of the donor pool. This is particularly important in Germany, where there is an ongoing shortage of organs and restrictive legislation regarding the expansion of the donor pool. Furthermore, the perfusion technology offers the possibility to serve as a platform for other ex situ and in situ therapies on isolated organs. In addition to the conditioning of pre-damaged organs for transplantation, this could lead to further applications in the context of targeted organ therapies and also to improved transplant logistics in the future.

Early U.S. Heart Transplant ExperienceWith Normothermic RegionalPerfusion Following Donation After Circulatory Death.

Heart transplantation following donation after circulatory death (DCD HT) has short-term survival outcomes comparable to donation after brain death and has led to a significant increase in transplantation volume. The U.S. experience with the normothermic regional perfusion (NRP) DCD HT procurement method has not been evaluated. The aim of this study was to examine short-term outcomes associated with NRP vs direct procurement and perfusion (DPP) methods used during DCD HT in the United States. The UNOS (United Network for Organ Sharing) registry was queried for all adult (age≥18 years) heart recipients and corresponding donors of controlled DCD HT from January 2019-December 2023. Transplantations were stratified by NRP or DPP reperfusion methods. The primary outcome was overall survival. A total of 918 heart donors and recipients met inclusion criteria, including 622 (68%) DPP and 296 (32%) NRP transplantations. Unadjusted Kaplan-Meier survival analysis demonstrated improved short-term survival associated with NRP (log-rank P = 0.005). After adjustment, DCD HT with NRP was independently associated with improved survival (HR: 0.39 [95%CI: 0.22-0.70]; P = 0.002). A propensity-matched analysis similarly demonstrated a cumulative survival benefit to NRP (log-rank P = 0.006). In this largest national series of DCD HT procurement perfusion strategies, NRP is associated with improved short-term survival as compared with DPP. This study evaluates the U.S. early experience with DCD HT, and longer-term follow-up data are needed to further assess the impact of DPP and NRP methods on post-heart transplantation outcomes.

Cerebral Oxygen Saturation Associates with Changes in Oxygen Transport Parameters during Cardiopulmonary Bypass.

(1) Background: Adequate organ perfusion during cardiopulmonary bypass (CPB) requires accurate estimation and adjustment of flow rates which conventional methods may not always achieve. Perioperative monitoring of cerebral oxygen saturation (ScO2) may detect changes in oxygen transport. This study aims to compare estimated and measured perfusion flow rates and assess the capacity of ScO2 to detect subtle changes in oxygen transport during CPB. (2) Methods: This observational study included 50 patients scheduled for elective coronary artery bypass grafting (CABG) surgery, all of whom provided written informed consent. Perfusion flow rates were estimated using the DuBois formula and measured using echocardiography and a flow probe in the arterial line of the CPB system. ScO2 was continuously monitored, alongside intermittent measurements of oxygen delivery and extraction ratios. (3) Results: Significant discrepancies were found between estimated flow rates (5.2 [4.8-5.5] L/min) and those measured at the start of the surgery (4.6 [4.0-5.0] L/min). These discrepancies were flow rate-dependent, being more pronounced at lower perfusion rates and diminishing as rates increased. Furthermore, ScO2 showed a consistent correlation with both oxygen delivery (r = 0.48) and oxygen extraction ratio (r = 0.45). (4) Conclusions: This study highlights discrepancies between estimated and actual perfusion flow rates during CPB and underscores the value of ScO2 monitoring as a continuous, noninvasive tool for maintaining adequate organ perfusion, suggesting a need for improved, patient-tailored perfusion strategies.

Innovative perfused cadaveric model for complete mesocolic excision.

A high-fidelity cadaver-based training scenario for right colectomy with complete mesocolic excision is presented (Video 1). A feasible perfusion strategy that allows a near-to-reality experience is demonstrated.

Liver non-contrast perfusion in diffuse liver diseases diagnostic algorithm: the new diagnostic criteria

Purpose: to define the new criteria for contrast-free ASL perfusion using for the management of diffuse liver diseases (DLD).Material and methods. Clinical and laboratory data, results of MRI with non-contrast MR perfusion (ASL-perfusion) of the liver were estimated in a group of patients with DLD (three-year research).Results. Potentials of assessment of liver ASL perfusion for patients with DLD (including complicated cases) are described in the article. It was established that ASL liver perfusion is useful for DLD clinical forms differential diagnosis, predicting the risk of liver cirrhosis, as well as complications (hepatic encephalopathy, sialoadenitis) and DLD exacerbation. The strategy of contrast-free MR perfusion using in patients with DLD management algorithm was developed.Conclusion. Liver ASL perfusion is a promising for the study and application method for the management of DLD.

Noteworthy in Cardiothoracic Surgery 2023.

Noteworthy in Cardiothoracic Surgery 2023 summarizes a few of the most high-impact trials and provocative trends in cardiothoracic surgery and transplantation this past year. Transplantation using organs procured from donation after circulatory death (DCD) continues to increase, and the American Society of Transplant Surgeons released recommendations on best practices in 2023. We review a summary of data on the impact of DCD on heart and lung transplantation. There has been increased interest in extracorporeal life support (ECLS), particularly after the COVID-19 pandemic, and we review the results of the highly discussed ECLS-SHOCK trial, which randomized patients in cardiogenic shock with planned revascularization to ECLS vs usual care. With improving survival outcomes in complex aortic surgery, there is a need for higher-quality evidence to guide which cooling and cerebral perfusion strategies may optimize cognitive outcomes in these patients. We review the short-term outcomes of the GOT ICE trial (Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest), a multicenter, randomized controlled trial of three different nadir temperatures, evaluating outcomes in cognition and associated changes in functional magnetic resonance imaging. Finally, both the Society of Thoracic Surgeons (STS) and the American College of Cardiology, American Heart Association, American College of Chest Physicians and Heart Rhythm Society (ACC/AHA/ACCP/HRS) updated atrial fibrillation guidelines in 2023, and we review surgically relevant updates to the guidelines and the evidence behind them.

Clinical outcome of a branch-first approach with a novel continuous whole-brain perfusion strategy for total arch surgery

BackgroundCerebral protection strategies have been investigated since the introduction of aortic arch surgery and have been modified over the centuries. However, the cerebral protective effects of unilateral and bilateral antegrade cerebral perfusion are similar, with opportunities for further improvement.MethodsA total of 30 patients who underwent total arch surgery were enrolled in this study. Patients were assigned to the novel continuous whole-brain or unilateral antegrade cerebral perfusion group according to the cerebral perfusion technique used. Preoperative clinical data and 1-year postoperative follow-up data were collected and analyzed.ResultsThere were no significant differences between the two groups in terms of the incidence of permanent neurological deficit, mortality, or therapeutic efficacy. However, the incidence of temporary neurological dysfunction in the novel whole-brain perfusion group was significantly lower than that in the unilateral antegrade cerebral perfusion group.ConclusionsIn this study, the branch-first approach with a novel whole-brain perfusion strategy had no obvious disadvantages compared with unilateral antegrade cerebral perfusion in terms of cerebral protection and surgical safety. These findings suggest that this new technique is feasible and has application value for total arch surgery.

Effective development of intensified perfusion culture based on shake tube semi-continuous bioreactors and optimal osmolarity constraint

The development of perfusion strategies supporting ultra-high cell growth and productivity for the intensified perfusion cultures (IPC) is very challenging. In this study, a novel approach was developed to address this issue by utilizing the shake tube semi-continuous bioreactors (ST) combining with a concentrated feed from the traditional fed-batch (TFB) platform. First, the impact of operating conditions in the ST were evaluated to identify those that best reflected the cell performance for the benchtop perfusion bioreactors (STR). Subsequently, the optimization of several key process parameters was performed in the ST along with the metabolic data obtained for the design of the IPC. Further, an empirical model to predict culture osmolarity was developed, verified, and subsequently utilized to determine the best combinations of the basal and feed perfusion rates ensuring the optimal osmolarity at the targeted viable cell density for the IPC process. Finally, the designed perfusion strategies were successfully validated in two IPC processes operated at 80 and 100×106 cells/m in the 3-L STR with an approximate 9-fold increase in cumulative titers compared to the TFB process. Overall, this study offers a novel and prospective method for the effective development of the IPC process to achieve significant process intensification.

Assessment of a goal-directed perfusion strategy through an oxygen delivery audit.

Evidence supports the role of oxygen delivery (DO2) in ameliorating acute kidney injury (AKI). While instrumentation for continuous DO2 measurement exists, a simplified method has been reported for targeting a specific DO2 index (DO2i), commonly referred to as a goal-directed perfusion (GDP) strategy, by using a reference table and available data such as body surface area and continuous haematocrit values. This simplified approach can also be used for quality auditing via archived data. This retrospective sequential audit was conducted to assess the impact of employing a GDP strategy within our institution by examining perfusion practices, DO2 levels and renal outcomes before and after implementation. A total of 246 patients undergoing elective primary coronary revascularisation were included: 125 patients in the pre-change group and 121 patients in the post-change group. A DO2i threshold above 280mL/min/m2 was targeted in the post-GDP group. While both groups maintained a mean DO2 above the threshold, the post-GDP group exhibited a higher average DO2i (311 vs 291mL/min/m2). The GDP strategy led to higher nadir DO2i (255 vs 225, p < .001) and was coupled with a reduction in the time below the 280mL/min/m2 threshold (30min vs 50min, p < .001). The average cardiac index in the post-GDP group was higher (1.87 vs 1.65, p < .001) while also demonstrating a smaller creatinine rise of 6.8% compared to 13.5% in the control group (p = .035). There was no difference in AKI or mortality rates between the groups. The implementation of the GDP strategy demonstrated an enhancement in oxygen delivery during cardiopulmonary bypass, primarily attributable to elevated pump flow rates. A statistically significant decrease in serum creatinine levels was observed. The published reference table emerged as a simple yet effective tool in optimising our GDP strategy.

Trilateral versus Bilateral Antegrade Cerebral Perfusion in Frozen Elephant Trunk: A Propensity Score Analysis.

Spinal cord injury (SCI) with subsequent paraplegia and/or stroke after arch repair with frozen elephant trunk (FET) remain the most devastating complications. In this study, we aim to examine the impact of different cerebral perfusion strategies on the neurological outcome comparing bilateral antegrade cerebral perfusion (bACP) and trilateral antegrade cerebral perfusion (tACP). Between 2009 and 2021, 88 patients underwent total arch replacement using a hybrid prosthesis in FET technique for acute (40.4%) and chronic (59.6%) aortic pathologies. After excluding 14 patients who underwent FET with unilateral ACP the remaining 74 patients were divided into two groups. Propensity score matching was performed based on pre- and perioperative patient characteristics resulting in 22 patients in each group. The primary endpoint was a combination of major cerebral event and SCI. Secondary end point was all-cause mortality. Major cerebral events occurred in 9% of the patients in bACP versus 13.6% in tACP group (p = 0.63). No postoperative SCI was observed in patients with bACP and only one patient suffered SCI with tACP (p = 0.31). There was no significant difference in 30-day mortality between the two groups (22.7% in bACP vs. 13.6% in tACP; p = 0.43). In patients undergoing total aortic arch repair using FET technique, both perfusion strategies (bilateral and trilateral ACP) are safe and effective. The rates of neurological complications as well as mortalities are acceptably low in both groups. Further studies with larger patient cohorts are warranted.

Carbon dioxide production index (VCO2i) predicts hyperlactatemia during cardiopulmonary bypass in pediatric carDiac surGery (pGDP- VCO2i): Study protocol for a nested case-control trial.

Hyperlactatemia (HL) during cardiopulmonary bypass (CPB) is relatively frequent in infants and associates with increased morbidity and mortality. Studies on adults have shown that carbon dioxide production index (VCO2i) during CPB is linked to the occurrence of HL, with 'critical thresholds' for VCO2i reported to be 60mL/min/m2. However, considering infants have a higher metabolic rate and lower tolerance to hypoxia, the critical threshold of VCO2i in infants cannot be replied to the existing adults' standards. The objective of this study is to investigate the association of VCO2i during CPB and HL, and explore the critical VCO2i threshold during CPB in infants. VCO2i predicts hyperlactatemia during cardiopulmonary bypass in pediatric cardiac surgery (pGDP-VCO2i) is a nested case-control study. A cohort of consecutive pediatric patients of less than 3years of age, undergoing congenital cardiac surgeries between May 2021 and December 2023 in West China Hospital will be enrolled. The VCO2i levels of each patient will be recorded every 5min during CPB. The primary outcome is the rate of HL. The infants will be divided into two groups based on the presence or not of HL. Pre- and intraoperative factors will be tested for independent association with HL. Then, we will make an analysis, and the critical value of VCO2i will be obtained. The postoperative outcome of patients with or without HL will be compared. This will be the first trial to investigate the association of VCO2i during CPB and HL, and explore the critical VCO2i threshold during CPB in pediatrics. The results of this study are expected to lay a foundation for clinical application of goal-directed perfusion (GDP) management strategy, and optimize the perfusion strategy and improve the prognosis of pediatric patients undergoing cardiac surgery. Chictr.org.cn, ChiCTR2100044296 on 16 March 2021.

Machine Perfusion and Bioengineering Strategies in Transplantation-Beyond the Emerging Concepts.

Solid organ transplantation has progressed rapidly over the decades from the first experimental procedures to its role in the modern era as an established treatment for end-stage organ disease. Solid organ transplantation including liver, kidney, pancreas, heart, and lung transplantation, is the definitive option for many patients, but despite the advances that have been made, there are still significant challenges in meeting the demand for viable donor grafts. Furthermore, post-operatively, the recipient faces several hurdles, including poor early outcomes like primary graft dysfunction and acute and chronic forms of graft rejection. In an effort to address these issues, innovations in organ engineering and treatment have been developed. This review covers efforts made to expand the donor pool including bioengineering techniques and the use of ex vivo graft perfusion. It also covers modifications and treatments that have been trialed, in addition to research efforts in both abdominal organs and thoracic organs. Overall, this article discusses recent innovations in machine perfusion and organ bioengineering with the aim of improving and increasing the quality of donor organs.