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Laser speckle imaging (LSI) is able to provide full-field perfusion maps of the renal cortex and allows quantification of the average LSI perfusion within an arbitrarily set region of interest and the recovery of LSI perfusion histograms within this region. The aim of the present study was to evaluate the use of LSI for mapping renal cortical microvascular perfusion and to demonstrate the capability of LSI to assess renal perfusion heterogeneities. The main findings were that: 1) full-field LSI measurements of renal microvascular perfusion were highly correlated to single-point LDV measurements; 2) LSI is able to detect differences in reperfusion dynamics following different durations of ischemia; and 3) renal microvascular perfusion heterogeneities can be quantitatively assessed by recovering LSI perfusion histograms.

Machine perfusion (MP) is a potential method to increase the donor pool for organ transplantation. However, MP systems for liver grafts remain difficult to use because of organ-specific demands. Our aim was to test a novel, portable MP system for hypothermic preservation of the liver. A portable, pressure-regulated, oxygenated MP system designed for kidney preservation was adapted to perfuse liver grafts via the portal vein (PV). Three porcine livers underwent 20 h of hypothermic perfusion using Belzer MP solution. The MP system was assessed for perfusate flow, temperature, venous pressure, and pO2 /pCO2 during the preservation period. Biochemical and histological parameters were analyzed to determine postpreservation organ damage. Perfusate flow through the PV increased over time from 157 ± 25 mL/min at start to 177 ± 25 mL/min after 20 h. PV pressure remained stable at 13 ± 1 mm Hg. Perfusate temperature increased from 9.7 ± 0.6°C at the start to 11.0 ± 0.0°C after 20 h. Aspartate aminotransferase and lactate dehydrogenase increased from 281 ± 158 and 308 ± 171 U/L after 1 h to 524 ± 163 and 537 ± 168 U/L after 20 h, respectively. Blood gas analysis showed a stable pO2 of 338 ± 20 mm Hg before perfusion of the liver and 125 ± 14 mm Hg after 1 h perfusion. The pCO2 increased from 15 ± 5 mm Hg after 1 h to 53 ± 4 mm Hg after 20 h. No histological changes were found after 20 h of MP. This study demonstrated the feasibility of a portable MP system for preservation of the liver and showed that continuous perfusion via the PV can be maintained with an oxygen-driven pump system without notable preservation damage of the organ.

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WHAT THIS PAPER ADDS A systematic review of the literature was performed adhering to the PRISMA guidelines with strict selection criteria for study design, patient inclusion and exclusion criteria, and outcome reporting. This contributed to comparability of the individual study data. Since 2006 many new studies have been performed and these are included in the systematic review. Strict definitions and outcome criteria were used to improve comparability between the outcome data of the included studies. Objective: Aortic graft infection (AGI) is a disastrous complication with an incidence of 0.2e6% in operated patients. With little or no high quality evidence, the best treatment option remains unclear. Therefore, the literature on the management of open abdominal AGI was systematically reviewed to determine optimal treatment. Methods: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review and meta-analysis was conducted for AGI. MEDLINE, Embase, and the Cochrane Database of Systematic Reviews were searched. Methodological quality was assessed using the Methodological Index for Non-randomised Studies (MINORS) score. Primary outcomes were 30 day mortality and one year survival. Secondary outcomes were survival, infection recurrence, limb salvage, and graft patency. Results: Of 1574 studies identified, 32 papers were included in the study. The overall quality of the studies was moderate, with an average MINORS score of 11.9. Pooled overall 30 day mortality and one year survival were 13.5% (95% CI 10.5e16.4) and 73.6% (95% CI 68.8e78.4), respectively. The lowest 30 day mortality and highest one year survival were found for in situ repair compared with extra-anatomic repair and for prosthetic grafts compared with venous grafts or arterial allografts. The infection recurrence rate was highest for prosthetic grafts. Conclusions: There is a lack of well designed, qualitative comparative studies making conclusive recommendations impossible. The current best available data suggests that partial graft removal should be avoided and the lowest 30 day mortality and best one year survival are achieved with in situ repair using prosthetic grafts. Initiatives such as the MAGIC database to collaboratively collect prospective data are an important step forward in obtaining more solid answers on this topic.

Intra-organ flow is the most critical parameter in machine-perfused organ preservation systems (MPS). Ultrasonic flow sensors (UFS) are commonly employed in MPS. However, UFS are sensitive to changes in fluid composition and temperature and require recalibration. Novel Coriolis-type mass flow sensors (CFS) may be more suitable for MPS because the measurement technique is not amenable to these factors. The effect of viscosity, colloids, temperature, pressure, and preservation solution on flow measurement accuracy of UFS and CFS was therefore investigated. A CFS-based MPS was built and validated for setpoint stability using porcine kidneys and the ability to reproduce different pressure and flow waveforms. The UFS exhibited a temperature- and preservation solution-dependent overestimation of flow rate compared to the CFS. The CFS deviated minimally from the actual flow rate and did not require recalibration. The CFS-based MPS conformed to the preprogrammed temperature, flow, pressure, and vascular resistance settings during 6-h kidney preservation. The system was also able to accurately reproduce different pressure and flow waveforms. Conclusively, CFS-based MPS are more suitable for organ preservation than UFS-based MPS. Our CFS-based MPS provides a versatile yet robust experimental platform for testing and validating different types of clinical and experimental MPS.

Based on these findings, we recommend that high-dose cefazolin be used for prophylaxis in (sub)normothermic organ preservation with PS.

HighlightsPAEF might have an atypical presentation.Colonoscopy, ultrasound and surgical examinations can be misleading.An aggressive diagnostic approach is indicated with the use of a CT-angiography.Surgical treatment is beneficial for the long-term outcome.