Magnetic resonance imaging during warm ex vivo kidney perfusion.

BACKGROUND: The shortage of donor organs for transplantation remains a worldwide problem. The utilization of suboptimal deceased donors enlarges the pool of potential organs, yet consequently, clinicians face the difficult decision of whether these sub-optimal organs are of sufficient quality for transplantation. Novel technologies could play a pivotal role in making pre-transplant organ assessment more objective and reliable. METHODS: Ex vivo normothermic machine perfusion (NMP) at temperatures around 35-37°C allows organ quality assessment in a near-physiological environment. Advanced magnetic resonance imaging (MRI) techniques convey unique information about an organ's structural and functional integrity. The concept of applying magnetic resonance imaging during renal normothermic machine perfusion is novel in both renal and radiological research and we have developed the first MRI-compatible NMP setup for human-sized kidneys. RESULTS: We were able to obtain a detailed and real-time view of ongoing processes inside renal grafts during ex vivo perfusion. This new technique can visualize structural abnormalities, quantify regional flow distribution, renal metabolism, and local oxygen availability, and track the distribution of ex vivo administered cellular therapy. CONCLUSION: This platform allows for advanced pre-transplant organ assessment, provides a new realistic tool for studies into renal physiology and metabolism, and may facilitate therapeutic tracing of pharmacological and cellular interventions to an isolated kidney.

Magnetic resonance imaging assessment of renal flow distribution patterns during ex vivo normothermic machine perfusion in porcine and human kidneys.

Acceptance criteria of deceased donor organs have gradually been extended toward suboptimal quality, posing an urgent need for more objective pre-transplant organ assessment. Ex vivo normothermic machine perfusion (NMP) combined with magnetic resonance imaging (MRI) could assist clinicians in deciding whether a donor kidney is suitable for transplantation. Aim of this study was to characterize the regional distribution of perfusate flow during NMP, to better understand how ex vivo kidney assessment protocols should eventually be designed. Nine porcine and 4 human discarded kidneys underwent 3 h of NMP in an MRI-compatible perfusion setup. Arterial spin labeling scans were performed every 15 min, resulting in perfusion-weighted images that visualize intrarenal flow distribution. At the start of NMP, all kidneys were mainly centrally perfused and it took time for the outer cortex to reach its physiological dominant perfusion state. Calculated corticomedullary ratios based on the perfusion maps reached a physiological range comparable to in vivo observations, but only after 1 to 2 h after the start of NMP. Before that, the functionally important renal cortex appeared severely underperfused. Our findings suggest that early functional NMP quality assessment markers may not reflect actual physiology and should therefore be interpreted with caution.

Core Outcome Set for Necrotizing Enterocolitis Treatment Trials.

BACKGROUND AND OBJECTIVES: Variability in outcome reporting in necrotizing enterocolitis (NEC) treatment trials hinders conducting meta-analyses and implementing novel treatments. We aimed to develop a core outcome set (COS) for NEC treatment trials including outcome measures most relevant to patients and physicians, from NEC diagnosis to adulthood. METHODS: Clinicians and/or researchers from low-middle- and high-income countries were approached based on their scientific contributions to NEC literature, and patients and parents through local organizations. We presented participants with 45 outcomes used in NEC research, identified through a systematic review. To achieve consensus, outcomes were rated on a scale of 1 to 9 in 3 online Delphi rounds, and discussed at a final consensus meeting. RESULTS: Seventy-one participants from 25 countries completed all Delphi rounds, including 15 patients and family representatives. Thirteen outcomes reached consensus in one of the stakeholder groups and were included in the consensus meeting, 6 outcomes reached consensus in both groups. Twenty-seven participants from both high- and low-middle-income countries attended the online consensus meeting, including family representatives and NEC patients. After discussion and a final vote, 5 outcomes reached consensus to be included: mortality, NEC-related mortality, short bowel syndrome, quality of life, and neurodevelopmental impairment. CONCLUSIONS: This NEC COS includes 5 predominantly long-term outcomes agreed upon by clinicians, patients, and family representatives. Use of this international COS will help standardize outcome selection in clinical trials, ensure these are relevant to those most affected by NEC care, and, ultimately, improve the care of infants with NEC.

Outcome Reporting in Interventional Necrotizing Enterocolitis Studies: A Systematic Review.

BACKGROUND: Despite an increasing necrotizing enterocolitis (NEC) incidence, treatment strategies have failed to make major advancements towards improved NEC outcomes. Heterogeneity in outcome reporting and a lack of treatment efficacy studies potentially hamper these advancements. We aimed to analyze outcome reporting in recent interventional NEC studies. METHODS: We performed a systematic review identifying interventional studies on NEC between 1st of January 2016 and 1st of June 2023 in MEDLINE, Embase, CENTRAL and Cochrane reviews. Systematic reviews, clinical trials and change-in-practice cohort studies reporting any therapeutic intervention for NEC patients (Bell's stage ≥ IIa) were eligible. We excluded studies on NEC diagnostics or prevention and non-English publications. Outcomes were categorized into five core areas and presented descriptively. The review was registered with PROSPERO (CRD42022302712). RESULTS: Out of 1.642 screened records, 65 were eligible for full-text review and 15 were finally included for data extraction. Median number of reported outcomes per article was six (range 1-19). We identified 66 unique outcomes, which were mapped to 53 outcome terms. Thirty-four out of the 53 of the outcome terms (64%) were only reported in a single article. Mortality was the most reported outcome (11/15 articles, 73%). Core area 'Adverse outcomes' contained the most outcome terms (n = 19), whereas 'Life impact' contained the least outcome terms (n = 4) and was represented in 3 articles (20%). CONCLUSIONS: Considerable heterogeneity in outcome reporting and a paucity of outcomes concerning 'Life impact' exist in interventional NEC studies. Development of a NEC core outcome set may improve consistency and patient-relevance in outcome reporting. STUDY TYPE: Systematic Review and Meta-Analyses. LEVEL OF EVIDENCE: III.

Safety and Feasibility of Indocyanine Green Fluorescence Angiography in Pediatric Gastrointestinal Surgery: A Systematic Review.

BACKGROUND: Although ICG-FA may be valuable in assessing anastomotic perfusion, reliable data on its use in pediatric gastrointestinal surgery is lacking. This systematic review analyzes whether ICG is useful for intestinal perfusion assessment in pediatric gastrointestinal surgery and safe to use in neonates. METHODS: Systematic searches of PubMed, EMBASE & MEDLINE and CENTRAL were performed (last conducted December 6, 2021). The main inclusion criteria were (1) use of ICG for intestinal perfusion assessment and (2) use of ICG in young infants. Exclusion criteria were lack of an English or Dutch full-text and MINORS quality score <60%. Data was presented in overview tables. The usefulness in pediatric gastrointestinal surgery was assessed by surgical outcome. Safety of ICG in neonates was assessed by complication or adverse event occurrence. RESULTS: Regarding intestinal perfusion assessment, four studies were included, reporting 45 patients (median age 1.5 years). ICG was considered useful for anastomotic blood flow evaluation and intraoperative determination of resection length. Regarding ICG safety in neonates, eight studies were included, reporting 46 infants (median age 24.9 days), of which 18 neonates. All but one studies reported the absence of complications or adverse events. Two studies reported subcutaneous dye retention, which fully disappeared within two weeks. CONCLUSION: Although the number of available studies is small, ICG might be useful for intraoperative intestinal perfusion assessment, perhaps even more than conventional clinical assessment. Furthermore, its safety profile looks promising in neonates. Larger prospective studies are necessary to confirm these assumptions and seem warranted given the safety profile. LEVELS OF EVIDENCE: Since this is a systematic review, a Level of Evidence for clinical studies cannot be determined for this manuscript.

Surgery or comfort care for neonates with surgical necrotizing enterocolitis: Lessons learned from behavioral artificial intelligence technology.

Background: Critical decision making in surgical necrotizing enterocolitis (NEC) is highly complex and hard to capture in decision rules due to case-specificity and high mortality risk. In this choice experiment, we aimed to identify the implicit weight of decision factors towards future decision support, and to assess potential differences between specialties or centers. Methods: Thirty-five hypothetical surgical NEC scenarios with different factor levels were evaluated by neonatal care experts of all Dutch neonatal care centers in an online environment, where a recommendation for surgery or comfort care was requested. We conducted choice analysis by constructing a binary logistic regression model according to behavioral artificial intelligence technology (BAIT). Results: Out of 109 invited neonatal care experts, 62 (57%) participated, including 45 neonatologists, 16 pediatric surgeons and one neonatology physician assistant. Cerebral ultrasound (Relative importance = 20%, OR = 4.06, 95% CI = 3.39-4.86) was the most important factor in the decision surgery versus comfort care in surgical NEC, nationwide and for all specialties and centers. Pediatric surgeons more often recommended surgery compared to neonatologists (62% vs. 57%, p = 0.03). For all centers, cerebral ultrasound, congenital comorbidity, hemodynamics and parental preferences were significant decision factors (p < 0.05). Sex (p = 0.14), growth since birth (p = 0.25), and estimated parental capacities (p = 0.06) had no significance in nationwide nor subgroup analyses. Conclusion: We demonstrated how BAIT can analyze the implicit weight of factors in the complex and critical decision for surgery or comfort care for (surgical) NEC. The findings reflect Dutch expertise, but the technique can be expanded internationally. After validation, our choice model/BAIT may function as decision aid.

Development of an international core outcome set for treatment trials in necrotizing enterocolitis-a study protocol.

AIM: Necrotizing enterocolitis (NEC) is the most lethal disease of the gastrointestinal tract of preterm infants. New and existing management strategies need clinical evaluation. Large heterogeneity exists in the selection, measurement, and reporting of outcome measures in NEC intervention studies. This hampers meta-analyses and the development of evidence-based management guidelines. We aim to develop a Core Outcome Set (COS) for NEC that includes the most relevant outcomes for patients and physicians, from moment of diagnosis into adulthood. This COS is designed for use in NEC treatment trials, in infants with confirmed NEC. METHODS: This study is designed according to COS-STAD (Core Outcome Set-STAndards for Development) recommendations and the COMET (Core Outcome Measures in Effectiveness Trials) Initiative Handbook. We obtained a waiver from the Ethics Review Board and prospectively registered this study with COMET (Study 1920). We will approach 125 clinicians and/or researchers from low-middle and high-income countries based on their scientific output (using SCIVAL, a bibliometric tool). Patients and parents will be approached through local patient organisations. Participants will be separated into three panels, to assess differences in priorities between former patients and parents (1. lay panel), clinicians and researchers involved in the neonatal period (2. neonatal panel) and after the neonatal period (3. post-neonatal panel). They will be presented with outcomes currently used in NEC research, identified through a systematic review, in a Delphi process. Eligible outcome domains are also identified from the patients and parents' perspectives. Using a consensus process, including three online Delphi rounds and a final face-to-face consensus meeting, the COS will be finalised and include outcomes deemed essential to all stakeholders: health care professionals, parents and patients' representatives. The final COS will be reported in accordance with the COS-Standards for reporting (COS-STAR) statement. CONCLUSIONS: Development of an international COS will help to improve homogeneity of outcome measure reporting in NEC, will enable adequate and efficient comparison of treatment strategies, and will help the interpretation and implementation of clinical trial results. This will contribute to high-quality evidence regarding the best treatment strategy for NEC in preterm infants.