H. Hentati

An Oxygenated and Transportable Machine Perfusion System Fully Rescues Liver Grafts Exposed to Lethal Ischemic Damage in a Pig Model of DCD Liver Transplantation.

Background Control of warm ischemia (WI) lesions that occur with donation after circulatory death (DCD) would significantly increase the donor pool for liver transplantation. We aimed to determine whether a novel, oxygenated and hypothermic machine perfusion device (HMP Airdrive system) improves the quality of livers derived from DCDs using a large animal model. Methods Cardiac arrest was induced in female large white pigs by intravenous injection of potassium chloride. After 60 minutes of WI, livers were flushed in situ with histidine-tryptophan-ketoglutarate and subsequently preserved either by simple cold storage (WI-SCS group) or HMP (WI-HMP group) using Belzer-MPS solution. Liver grafts procured from heart-beating donors and preserved by SCS served as controls. After 4 hours of preservation, all livers were transplanted. Results All recipients in WI-SCS group died within 6 hours after transplantation. In contrast, the HMP device fully protected the liver against lethal ischemia/reperfusion injury, allowing 100% survival rate. A postreperfusion syndrome was observed in all animals of the WI-SCS group but none of the control or WI-HMP groups. After reperfusion, HMP-preserved livers functioned better and showed less hepatocellular and endothelial cell injury, in agreement with better-preserved liver histology relative to WI-SCS group. In addition to improved energy metabolism, this protective effect was associated with an attenuation of inflammatory response, oxidative load, endoplasmic reticulum stress, mitochondrial damage, and apoptosis. Conclusions This study demonstrates for the first time the efficacy of the HMP Airdrive system to protect liver grafts from lethal ischemic damage before transplantation in a clinically relevant DCD model.

Real-time assessment of intestinal viability using indocyanine green fluorescent imaging (with video).

Indocyanineuorescent imaging;Intestinal viability;Intraoperativeischemia assessmentOne of the major concerns in colorectal surgery is to assess the viability of a colorectalanastomosis in situ, because poor vascularization is considered to be a risk factor foranastomotic leakage. For some groups, any intraoperative doubts about intestinal viabilitymust be followed by a ‘‘second look’’ at 24 or 48hours because there are no consensualmethod (i.e., clinical, biological, or morphological) to assess the vascular supply of thedigestive tube. Imaging detection based on the uorescence properties of indocyaninegreen has been recently developed in liver surgery for the identication of the bile ductsand livercancersduringsurgery[1].Thistechniquealsoallowsvisualizingvesselswithintheintestine and the surrounding tissues [2]. It has been recently validated in animal modelsof intestinal ischemia [3]. Here, in this video vignette, we detail the use of indocyaninegreen (ICG) uorescent imaging to intraoperatively evaluate the intestinal perfusion andviability during bowel surgery.A 66-year-old woman, without any past medical history, was admitted to our hos-pital with episodes of abdominal pain. The physical examination revealed severe anddiffuse abdominal tenderness and muscle guarding. Computed tomography showed mod-erate ascites and several dilated intestinal loops. The diagnosis of small bowel ischemiawas considered, and an immediate laparotomy was performed. The laparotomy ndingsshowed a massive small intestinal necrosis.Intraoperatively, 12.5mg (5mL) of ICG (Infracyanine, Laboratoire Serb, Paris, France)was injected into a peripheral vein. The device (Photo Dynamic Eye PDE: HamamatsuPhotonics Co) was used for intraoperative uorescent images of small bowel. Beforesmall bowel resection, the uorescent imaging clearly delineated the necrotic regionsof the small bowel. After resection, the serosal surface color of distal part of the resid-ual ileum showed a slightly darker hue than the proximal part of the residual jejunum.

Authors’ Reply: Risk Factors for Mortality and Morbidity in Elderly Patients Presenting with Digestive Surgical Emergencies

We thank Li et al. for their interest to our article recently published in the World Journal of Surgery [1]. We agree that our study includes several limitations that we have already mentioned in the discussion section. First, we used 12 g/dL as the cutoff value of preoperative hemoglobin level. This is the lower limit which was defined by the local laboratory at our institution. Second, as for the statistical analysis, we performed multivariate binary logistic regression model. We deliberately published the final results of the analysis. Finally, we agree that scores including intra-operative variables, such as Surgical Apgar Score, Surgical Risk Score, E-POSSUM, APACHE II score and others, are of utmost importance and could predict postoperative morbidity and mortality. However, as already mentioned in the discussion section, we did not use these scores in our study since they include perioperative variables, and therefore, they do not aid a given patient in making the decision on whether to accept or decline emergent surgery. Therefore, we only analyzed preoperative variables in the present study to achieve the study’s objective (i.e., to identify preoperative predictors of postoperative mortality and morbidity), which may help the surgical team in making the decision on whether to perform or avoid futile surgery.

Thymoquinone protects rat liver after partial hepatectomy under ischaemia/reperfusion through oxidative stress and endoplasmic reticulum stress prevention

Ischaemia reperfusion (I/R) is associated with liver injury and impaired regeneration during partial hepatectomy (PH). The aim of this study was to investigate the effect of thymoquinone (TQ), the active compound of essential oil obtained from Nigella sativa seeds, on rat liver after PH. Male Wistar rats were divided equally into four groups (n = 6) receiving an oral administration of either vehicle solution (sham and PH groups) or TQ at 30 mg/kg (TQ and TQ + PH groups) for 10 consecutive days. Then, rats underwent PH (70%) with 60 minutes of ischaemia followed by 24 hours of reperfusion (PH and TQ + PH groups). Alanine aminotransferase (ALT) activity and histopathological damage were determined. Also, antioxidant parameters, liver regeneration index, hepatic adenosine triphosphate (ATP) content, endoplasmic reticulum (ER) stress and apoptosis were assessed. In response to PH under I/R, liver damage was significantly alleviated by TQ treatment as evidenced by the decrease in ALT activity (P < .01) and histological findings (P < .001). In parallel, TQ preconditioning increased hepatic antioxidant capacities. Moreover, TQ improved mitochondrial function (ATP, P < .05), attenuated ER stress parameters and repressed the expression of apoptotic effectors. Taken together, our results suggest that TQ preconditioning could be an effective strategy to reduce liver injury after PH under I/R. The protective effects were mediated by the increase of antioxidant capacities and the decrease of ER stress and apoptosis.