Performed On Postoperative Day Research Articles

In Vivo Engineering and Transplantation of Axially Vascularized and Epithelialized Flaps in Rats.

The arteriovenous loop (AVL) model allows the in vivo engineering of axially vascularized flaps, the so-called AVL flaps. Although AVL flaps can be transplanted microsurgically to cover tissue defects, they lack an epithelial layer on the surface. Therefore, the objective of this study was to engineer axially vascularized AVL flaps with an accompanying epithelial layer for local defect reconstruction. In this study, AVLs were established in 20 male Lewis rats. Minimally invasive injection of keratinocytes onto the surface of the AVL flaps was performed on postoperative day (POD) 21. AVL flaps were explanted from 12 rats on POD 24 or POD 30, then the epithelium formed by the keratinocytes on the surface of the flaps was evaluated using immunofluorescence staining. In six other rats, the AVL flap was locally transposed to cover a critical defect in the rats' leg on POD 30 and explanted for analysis on POD 40. In two control rats, sodium chloride was applied instead of keratinocytes. These control flaps were also transplanted on POD 30 and explanted on POD 40. Our results revealed that 3 days after keratinocyte application, a loose single-layered epithelium was observed histologically on the AVL flaps surface, whereas after 9 days, a multilayered and structured epithelium had grown. The epithelium on the transplanted AVL flaps showed its physiological differentiation when being exposed to an air-liquid interface. Histologically, a layered epithelium identical to the rats' regular skin was formed. In the sodium chloride control group, no epithelium had been grown. This study clearly demonstrates that axially vascularized AVL flaps can be processed in the subcutaneous chamber by minimally invasive injection of keratinocytes. Thus, AVL flaps with an intact epithelial layer were engineered and could be successfully transplanted for local defect coverage in a small animal model.

High amylase concentration in drainage liquid can early predict proximal and distal intestinal anastomotic leakages: A prospective observational study.

Anastomotic leak (AL) is a serious complication in digestive surgery. Early diagnosis might allow clinicians to anticipate appropriate management. The aim of this study was to assess the predictive value of amylase concentration in drain fluid for the early diagnosis of digestive tract AL. Hundred and fourteen consecutive patients "at risk" of AL, in whom a flexible drainage was placed by surgeon's choice after digestive anastomosis were included. Patients with eso-gastric, bilio-digestive, and pancreatic anastomoses were excluded. Drain amylase measurement (DAM) was routinely performed on postoperative day (POD) 1, 3, 5-7. DAM values were compared between patients with postoperative AL versus patients without AL. A receiver-operating curve (ROC) with calculation of the areas under the ROC curves area under curves was performed and a cutoff value of DAM was calculated. AL occurred in 25 patients (AL group) and 89 patients did not present AL (C group). The mean DAM was significantly higher in AL group versus C Group on POD 1, 3, and 5. A cutoff value of 307 IU/L predicted the occurrence of AL with a sensitivity and specificity of 91% and 100%, respectively. Positive and negative predictive values were 100% and 97.5%, respectively. Patients with AL had an elevated DAM prior to the appearance of any clinical signs of AL. High level DAM could accurately predict AL for proximal and distal digestive tract anastomoses. This simple, noninvasive, and low-cost method can accurately predict early AL and help physicians to perform appropriate imaging and treatment.

Staged left ventricular recruitment facilitated by Sano conduit upsizing

Staged left ventricular recruitment facilitated by Sano conduit upsizing

Splenic volume and splenic vein diameter are independent pre-operative risk factors of portal vein thrombosis after splenectomy: a retrospective cohort study

BackgroundPortal vein thrombosis (PVT) is a common complication following splenectomy. It affects between 5 and 55% of patients undergoing surgery with no clearly defined pre-operative risk factors. The aim of this study was to determine the pre-operative risk factors of PVT.Patients and methodSingle centre, retrospective study of data compiled for every consecutive patient who underwent splenectomy at Toulouse University Hospital between January 2009 and January 2019. Patients with pre- and post-surgical CT scans have been included.Results149 out of 261 patients were enrolled in the study (59% were males, mean age 52 years). The indications for splenectomy were splenic trauma (30.9%), malignant haemopathy (26.8%) and immune thrombocytopenia (8.0%). Twenty-nine cases of PVT (19.5%) were diagnosed based on a post-operative CT scan performed on post-operative day (POD) 5. Univariate analysis identifies three main risk factors associated with post-operative PVT: estimated splenic weight exceeding 500 g with an OR of 8.72 95% CI (3.3–22.9), splenic vein diameter over 10 mm with an OR of 4.92 95% CI (2.1–11.8) and lymphoma with an OR of 7.39 (2.7–20.1). The role of splenic vein diameter with an OR of 3.03 95% CI (1.1–8.6), and splenic weight with an OR of 5.22 (1.8–15.2), as independent risk factors is confirmed by multivariate analysis. A screening test based on a POD 5 CT scan with one or two of these items present could indicate sensitivity of 86.2% and specificity of 86.7%.ConclusionThis study suggests that pre-operative CT scan findings could predict post-operative PVT. A CT scan should be performed on POD 5 if a risk factor has been identified prior to surgery.

Association of Postoperative Neutrophil Lymphocyte Ratio (NLR) and Monocyte Lymphocyte Ratio (MLR) with the Presence of Osteoporosis in Japanese Patients after Hip Fracture Surgery: A Retrospective Cohort Study.

Background The diagnosis of osteoporosis is based on bone mineral density measurements expressed as a percentage of the young adult mean (YAM) in Japan. Osteoporosis is defined as YAM <70%, and intervention is recommended at this cutoff. Because osteoporosis has a strong association with systemic metabolic disorders, we postulated that patients with YAM <70% had higher inflammatory biomarker concentrations owing to the higher systemic stress compared with YAM >70%. Method We retrospectively reviewed 94 patients with low-trauma hip fractures. Blood examinations were performed on postoperative day (POD) 1 and POD 7. We used neutrophil lymphocyte ratio (NLR) and monocyte lymphocyte ratio (MLR) to evaluate postoperative recovery. After dividing the 94 patients into two groups according to a YAM cutoff of 70%, we compared the differences in NLR and MLR. Results On POD 1, patients with YAM >70% had a median NLR of 5.7 and a median MLR of 0.66, which were significantly lower than for patients with YAM <70% (8.8 and 0.9, respectively). Similarly, on POD 7, patients with YAM >70% had a median NLR of 2.0 and a median MLR of 0.31, which were significantly lower than for patients with YAM <70% (3.5 and 0.43, respectively). Conclusion A YAM cutoff of 70% is an appropriate intervention threshold regarding postoperative recovery after hip fracture surgery. Mini-. Patients with YAM >70% showed lower NLR and MLR on POD 1 and POD 7. A YAM cuffoff of 70% is an appropriate intervention threshold regarding postoperative recovery after hip fracture surgery.

Alterations in portal flow dynamics following total pancreatectomy and autologous islet cell transplant

Introduction: The aim of this study is to evaluate doppler ultrasonography (DUS) flow dynamics following total pancreatectomy and autologous islet cell transplant (TPAIT). Methods: Retrospective analysis of prospectively collected data was done from February 2018 to September 2019. DUS measuring portal vein (PV) branch velocity (PVV) was performed on post-operative day (POD) 1, 2, and 5, and as applicable due to abnormal liver function tests (LFT). Results: Fifteen cases of TPAIT were performed. The mean change in PV pressure at infusion was 5.4 cm H2O [1.5 -26 (SD 6.3)]. The lowest mean flow was observed on POD 1 in the main and right posterior PV; on POD 2 in the right anterior and left PV. Correlation analysis showed weak correlation between LFTs and PVV, not significant until POD 5 (r = 0.55, p = 0.04). In the post-discharge period LFTs and PVV correlation was strongly statistically significant (r = 1.0, p-value < 0.001). There was a strong negative correlation between islet cell volume infused and right anterior PVV on POD 2 (r = -0.88, p = 0.02). Islet cell mass and PVV did not significantly correlate until POD 5 (r = 0.80, p = 0.03). No patients had PVT. Two patients had post-operative bleeding, both of which had extremely low velocities (main PVV 0.181). Conclusion: The correlation between PVV and LFTs is not significant until the post-discharge period when US is performed due to clinical concern rather than protocol. The value of scheduled post-operative velocity measurement may be overstated.

Gangrene, revascularization, and limb function improved with E-selectin/adeno-associated virus gene therapy

ObjectiveNovel therapeutic angiogenic concepts for critical limb ischemia are still needed for limb salvage. E-selectin, a cell-adhesion molecule, is vital for recruitment of the stem/progenitor cells necessary for neovascularization in ischemic tissues. We hypothesized that priming ischemic limb tissue with E-selectin/adeno-associated virus (AAV) gene therapy, in a murine hindlimb ischemia and gangrene model, would increase therapeutic angiogenesis and improve gangrene. MethodsFVB/NJ mice were given intramuscular hindlimb injections of either E-selectin/AAV or LacZ/AAV and then underwent induction of gangrene via femoral artery ligation and concomitant systemic injections of the nitric oxide synthesis inhibitor L-NAME (L-NG-Nitro arginine methyl ester; 40 mg/kg). Gangrene was evaluated via the Faber hindlimb appearance score. The rate of ischemic limb reperfusion and ischemic tissue angiogenesis were evaluated using laser Doppler perfusion imaging and DiI perfusion with confocal laser scanning microscopy of the ischemic footpads, respectively. The treadmill exhaustion test was performed on postoperative day (POD) 8 to determine hindlimb functionality. ResultsThe E-selectin/AAV–treated mice (n = 10) had decreased Faber ischemia scores compared with those of the LacZ/AAV–treated mice (n = 7) at both PODs 7 and 14 (P < .05 and P < .01, respectively), improved laser Doppler perfusion imaging reperfusion indexes by POD 14 (P < .01), and greater gangrene footpad capillary density (P < .001). E-selectin/AAV–treated mice also had improved exercise tolerance (P < .05) and lower relative muscular atrophy (P < .01). ConclusionWe surmised that E-selectin/AAV gene therapy would significantly promote hindlimb angiogenesis, reperfusion, and limb functionality in mice with hindlimb ischemia and gangrene. Our findings highlight the reported novel gene therapy approach to critical limb ischemia as a potential therapeutic option for future clinical studies.

THE IMPACT OF OXYGEN FREE RADICAL SCAVENGER ON ACUTE REJECTION IN A HISTOCOMPATIBLE MINIATURE SWINE MODEL

Introduction: Vascularized Composite Allotransplantations (VCAs), like solid organ transplants, are very susceptible to ischemia-reperfusion injury (IRI). IRI leads to tissue hypoxia and the formation of oxygen free radicals which triggers T-cell accumulation and complement activation, causing increased antigenicity of the transplanted tissue. In this study we demonstrate the effect of two oxygen free radical scavengers on acute rejection in a histocompatible miniature swine model. Materials and Methods: To conduct this study, we used our well-established myocutaneous flap model in a major histocompatibility complex (MHC)-defined miniature swine. MHC class I and II antigens were matched between donors and recipients. Myocutaneous allografts consisted of an isolated skin pad with the underlying gracilis muscle. All flaps were treated with similar concentrations of either Saline (9mg/ml, n=2), Sodium Iodide (10mg/ml, n=3) or Hydrogen Sulfide (H2S) (11.6mg/ml). Flaps were subjected to an intermediate ischemia time of 3 hours at 4°C immediately after harvest. End of ischemia time was marked by unclamping the anastomosis. Daily blood draws were performed on postoperative day (POD) 0 to 7, 14 and end of study. Biopsies for histological analysis were collected on POD 4, 10, 14 and end of study. Rejection was assessed by an independent pathologist following the Banff criteria (Grade 0-IV) for skin containing VCA. Results: On POD 4, flaps treated with H2S showed Grade 0 of rejection according to the Banff classification, compared to Grade I in the Sodium Iodide group and Grade II in the Saline. There was no significant difference in grade of rejection between these three groups on or after POD 10.Discussion: Treatment of ischemic myocutaneous flaps with oxygen free radical scavengers delayed acute rejection when compared to saline treated controls. Currently, standard immunosuppression regimens and techniques for graft preservation of VCA do not enable preconditioning of the donor or ischemic-free storage. Therefore, IRI is unavoidable in VCA so far. Diminishing the impact of IRI could reduce local secretion of pro-inflammatory cytokines and sequester recruitment of alloreactive immune cells to the transplant, delaying acute rejection episodes during the immediate post-operative period. Conclusion: With this study we demonstrate the impact of oxygen free radical scavengers on IRI in an immunocompetent and genetically well-defined large animal model. Treating myocutaneous flaps accordingly abrogates early rejection histopathologically at POD 4. Further experiments are ongoing to titrate the impact of these scavengers across later timepoints.

The effects of optimizing blood inflow in the pedicle on perforator flap survival: A pilot study in a rat model.

BackgroundPerforator flaps have led to a revolution in reconstructive surgery by reducing donor site morbidity. However, many surgeons have witnessed partial flap necrosis. Experimental methods to increase inflow have relied on adding a separate pedicle to the flap. The aim of our study was to experimentally determine whether increasing blood flow in the perforator pedicle itself could benefit flap survival.MethodsIn 30 male Lewis rats, an extended posterior thigh perforator flap was elevated and the pedicle was dissected to its origin from the femoral vessels. The rats were assigned to three groups: control (group I), acute inflow (group II) and arterial preconditioning (group III) depending on the timing of ligation of the femoral artery distal to the site of pedicle emergence. Digital planimetry was performed on postoperative day (POD) 7 and all flaps were monitored using laser Doppler flowmetry perioperatively and postoperatively in three regions (P1-proximal flap, P2-middle of the flap, P3-distal flap).ResultsDigital planimetry showed the highest area of survival in group II (78.12%±8.38%), followed by groups III and I. The laser Doppler results showed statistically significant higher values in group II on POD 7 for P2 and P3. At P3, only group II recorded an increase in the flow on POD 7 in comparison to POD 1.ConclusionsOptimization of arterial inflow, regardless if performed acutely or as preconditioning, led to increased flap survival in a rat perforator flap model.

An Investigation of Factors Related to Food Intake Ability and Swallowing Difficulty After Surgery for Thoracic Esophageal Cancer

Swallowing difficulty is among the major complications that can occur after surgery for thoracic esophageal cancer. Recurrent laryngeal nerve paralysis (RLNP) has been considered the most significant cause of a postoperative swallowing difficulty, but association between the two has not been adequately explained. We investigated the relation between postoperative RLNP and swallowing difficulty by means of video fluoroscopy. Our study included 32 patients who underwent subtotal esophagectomy for thoracic esophageal cancer at St. Marianna University School of Medicine between April 2014 and March 2017. We evaluated patients’ age and sex, disease stage, preoperative presence of a swallowing difficulty, nutritional status, extent and duration of surgery, blood loss volume, and postoperative presence of RLNP and/or hoarseness. Patients were divided into two groups according to whether oral food intake was possible when video fluoroscopy was performed on postoperative day (POD) 7, and we analyzed the associated factors. Postoperative RLNP occurred in 21 patients (65.6%); hoarseness occurred in 19 (59.4%). Eleven patients (34.4%) suffered swallowing difficulty that prevented food intake. No significant association was found between postoperative swallowing difficulty and postoperative RLNP or hoarseness, but a significant relation was found between the prognostic nutritional index and intraoperative lymph node dissection. Multivariable analysis revealed a significant relation between postoperative swallowing difficulty and only one factor: cervical lymph node dissection (P = 0.0075). There appears to be no relation between RLNP pursuant to esophageal cancer surgery and swallowing difficulty that prevents oral food intake.

Using functional magnetic resonance imaging to evaluate an acute allograft rejection model in rats

PurposeTo assess the longitudinal changes of allograft pathophysiology by intravoxel incoherent motion (IVIM) and blood oxygen level-dependent (BOLD) MRI in a rat model of acute renal allograft rejection. Materials and methodsAcute rejection (AR) was induced by transplantation of Dark Agouti donor kidneys into Lewis recipients (n = 18). A Lewis-Lewis rat syngeneically transplanted (sTX) model served as the control (n = 6). Acute tubular necrosis (n = 6) and acute calcineurin inhibitor toxicity (n = 6) groups were established using Lewis rats. MRI was performed on postoperative day (POD) 1, 4 and 7 in the allogeneically transplanted (aTX) group and on POD4 in the other groups. Histological evaluation and PCR were performed. ResultsAfter the allogenic transplantation, all MRI parameters of allograft further decreased until POD7, and the D and ADC values in the cortex were significantly lower than that in the sTX group (1.03 ± 0.09 vs 1.52 ± 0.09 × 10−3 mm2/s, Padj < 0.05; 1.21 ± 0.03 vs 1.78 ± 0.07 × 10−3 mm2/s, Padj < 0.05). The D*, f and R2* values of the aTX group in the cortex and medulla were significantly lower than those in the sTX group on POD7 (cortex, D*: 25.60 ± 4.78 vs 69.32 ± 9.79 × 10−3 mm2/s, Padj < 0.05; f: 7.84 ± 1.83 vs 20.34 ± 3.08%, Padj < 0.05; R2*: 16.61 ± 4.18 vs 31.48 ± 6.43 1/s, Padj < 0.05; medulla, D*: 13.59 ± 6.08 vs 62.75 ± 9.20 × 10−3 mm2/s, Padj < 0.05; f: 7.46 ± 1.62 vs 14.68 ± 2.05%, Padj < 0.05; R2*: 21.59 ± 3.45 vs 39.53 ± 4.34 1/s, Padj < 0.05). AR grafts presented serve interstitial inflammation, tubulitis and infiltration of T-lymphocytes and macrophages. The MRI parameters, including D, ADC, D*, f and R2*, were significantly correlated with the histological changes, cell infiltration and inflammatory cytokine mRNA levels. ConclusionsIVIM coupled with BOLD MRI allows longitudinal assessment of allograft diffusion, perfusion and oxygen consumption impairment caused by acute renal allograft rejection in rat model.

Effect of Lens Fragmentation Patterns on Phacoemulsification Parameters and Postoperative Inflammation in Femtosecond Laser-Assisted Cataract Surgery

ABSTRACTPurpose: To evaluate intraoperative and postoperative outcomes with “chop” or “matrix” lens fragmentation patterns in femtosecond laser-assisted cataract surgery.Methods: Prospective comparative study of 66 eyes with grade III–IV nuclear sclerosis was conducted at an apex tertiary care ophthalmic center. Cases were randomly allocated to undergo femtosecond laser pretreatment using matrix pattern (group I; n = 33) or chop pattern (group II; n = 33) of lens fragmentation (LenSx laser platform), followed by phacoemulsification. The primary outcome measures were intraoperative phacoemulsification parameters and postoperative anterior chamber (AC) flare. Secondary outcome measures were intraoperative complications, postoperative central macular thickness, visual acuity, and endothelial cell counts. Follow-up was performed on postoperative day (POD) 1 and 30.Results: Phacoemulsification parameters including cumulative dissipated energy (p = 0.008), ultrasonic time (p = 0.001), aspiration time (p < 0.001), and total duration (p = 0.001) were significantly less in group I. The AC flare was 9.8 ± 4.6 in group I and 15.4 ± 6.0 in group II (p < 0.001) on POD 1, and the difference persisted at 1 month. A highly significant positive correlation was observed between the total duration of phacoemulsification and AC flare (p < 0.001). No case developed cystoid macular edema. The postoperative specular counts were significantly less in group II on POD 1 (p = 0.036) and POD 30 (p = 0.02). There was no difference in visual acuity between the two groups, and intraoperative complications were not observed in any case.Conclusion: A decrease in phacoemulsification time and energy is observed after femtosecond laser pretreatment with the matrix pattern of lens fragmentation as compared to the chop pattern. The endothelial cell loss and postoperative inflammation is significantly less with the matrix pattern, and the inflammation correlates with the duration of phacoemulsification.

Vascular endothelial growth factor accelerates compensatory lung growth by increasing the alveolar units.

BackgroundDeficiency of vascular endothelial growth factor (VEGF) is associated with hypoplastic lung diseases such as congenital diaphragmatic hernia (CDH). Provision of VEGF has been demonstrated to be beneficial in hyperoxia-induced bronchopulmonary dysplasia and thus could induce lung growth and improve outcome in hypoplastic lung diseases. We aimed to determine the effects of exogenous VEGF in a rodent model of compensatory lung growth after left pneumonectomy.MethodsEight-ten-week-old C57Bl6 male mice underwent left pneumonectomy followed by daily intra-peritoneal injections of saline or VEGF (0.5 mg/kg). Lung volume measurement, pulmonary function tests, and morphometric analyses were performed on post-operative day (POD) 4 and 10. Pulmonary expression of angiogenic factors was analyzed by quantitative polymerase chain reaction and western blot.ResultsLung volume on POD 4 was higher in the VEGF-treated mice (P = 0.03). On morphometric analyses, VEGF increased parenchymal volume (P = 0.001), alveolar volume (P = 0.0003), and alveolar number (P < 0.0001) on POD 4. The VEGF group displayed higher levels of phosphorylated-VEGFR2/VEGFR2 (P = 0.03) and epidermal growth factor (EGF) mRNA (P = 0.01).ConclusionVEGF accelerated compensatory lung growth in mice by increasing alveolar units. These changes may be mediated by VEGFR2 and EGF-dependent mechanisms.

Isolated Common Hepatic Duct Injury after Blunt Abdominal Trauma

Extrahepatic bile duct injury is commonly associated with hepatic, duodenal, or pancreatic injuries, and isolated extrahepatic bile duct injury is rare. We report a patient who presented with an isolated extrahepatic bile duct injury after blunt trauma. A 50-year-old man was referred to our hospital after having suffered a fall down injury. His laboratory findings showed hyperbiliribinemia with elevated aspartate aminotransferase and alanine aminotransferase level. Initial abdominal computed tomography (CT) showed a mild degree of hemoperitoneum without evidence of abdominal solid organ injury. On the 3rd day of hospitalization, the patient complained of dyspnea and severe abdominal discomfort. Follow-up abdominal CT showed no significant interval change. Owing to the patient’s condition, Emergency laparotomy revealed a large amount of bile-containing fluid collection and about 1 cm in size laceration on the left lateral side of the common hepatic duct. Primary repair of the injured bile duct with T-tube insertion was performed On postoperative day (POD) 30, endoscopic retrograde cholangiopancreatography showed minimal bile leakage and endoscopic sphincteroplasty and endoscopic retrograde biliary drainage were performed. On POD 61, the T-tube was removed and the patient was discharged. Keywords: Abdominal injuries; Hepatic duct

Percutaneous Microwave Ablation Liver Partition and Portal Vein Embolization for Rapid Liver Regeneration: A Minimally Invasive First Step of ALPPS for Hepatocellular Carcinoma.

Percutaneous Microwave Ablation Liver Partition and Portal Vein Embolization for Rapid Liver Regeneration: A Minimally Invasive First Step of ALPPS for Hepatocellular Carcinoma.

Reducing Colorectal Anastomotic Leakage with Tissue Adhesive in Experimental Inflammatory Bowel Disease

Anastomotic leakage after gastrointestinal surgery remains a challenging clinical problem. This study aimed to investigate the effectiveness of TissuCol (fibrin glue), Histoacryl Flex (n-butyl-2-cyanoacrylate), and Duraseal (polyethylene glycol) on colorectal anastomotic healing during experimental colitis. We first performed colectomy 7 days after 10 mg trinitrobenzene sulfonic acid (TNBS)-induced colitis to validate a rat TNBS-colitis-colectomy model. Subsequently, this TNBS-colitis-colectomy model was used in 73 Wistar rats that were stratified into a colitis group (CG, no adhesive), a TissuCol group (TG), a Histoacryl group (HG), and a Duraseal group (DG). Anastomotic sealant was applied with one adhesive after constructing an end-to-end hand-sewn anastomosis. Clinical manifestations, anastomotic bursting pressure, and immunohistochemistry of macrophage type-one (M1) and type-two (M2) was performed on postoperative day (POD)3 or POD7. TNBS-caused mucosal and submucosal colon damage and compromised anastomotic healing (i.e., abscess formation and low anastomotic bursting pressure). On POD3, higher severity of abscesses was seen in CG. Average anastomotic bursting pressure was 53.2 ± 35.5 mm Hg in CG, which was significantly lower than HG (134.4 ± 27.5 mm Hg) and DG (95.1 ± 54.3 mm Hg) but not TG (83.4 ± 46.7 mm Hg). Furthermore, a significantly higher M2/M1 index was found in HG. On POD7, abscesses were only seen in CG (6/9) but not in other groups; HG had the lowest severity of adhesion. We describe the first surgical IBD model by performing colectomy in rats with TNBS-induced colitis, which causes intra-abdominal abscess formation and compromises anastomotic healing. Anastomotic sealing with Histoacryl Flex prevents these complications in this model. Alternative activation of macrophages seems to be involved in its influence on anastomotic healing.

Is Routine Imaging Necessary After Pancreatic Resection?

This study aimed to assess whether routine transabdominal ultrasonography (US) is clinically helpful for the early detection of postoperative pancreatic fistula (PF). In a prospective cohort of patients undergoing partial pancreatectomy, US was performed on postoperative day (POD) 3. Potential predictors of PF, including amylase value in drains (AVD) on POD 1, were investigated. A tree-based classification model of the independent predictors of PF was also performed. One hundred seventy-three patients were analyzed. A peripancreatic collection on US and an AVD 5000 U/L or greater on POD 1 were predictors of PF. In the tree-based classification model, patients were stratified by AVD on POD 1. For values less than 5000 U/L (incidence of PF, 11.3%), US had a sensitivity of 23.1% and a specificity of 97.5%. For AVD 5000 U/L or greater (incidence of PF, 70.7%), sensitivity was 46.3% and specificity was 100%. Despite the presence of a peripancreatic collection as a predictor of PF, US-as a diagnostic test-resulted to be highly specific but poorly sensitive even in the tree-based classification model. Therefore, its role does not seem to be clinically relevant and does not add value to AVD on POD 1, which remains the most powerful and relevant early predictor of PF.

Abstract 18310: Therapeutic Use of Encapsulated Genetically Engineered Mesenchymal Stem Cells for Vascular Regeneration

Background: We have previously shown that encapsulation of mesenchymal stem cells (MSCs) in alginate improves cell retention and efficacy of stem cell therapies in the hind limb model of vascular insufficiency. Erythropoietin (EPO), a hematopoietic cytokine, is also known as an angiogenic factor. The purpose of this study is to evaluate the efficacy of encapsulated, gene transfected MSCs as therapeutic strategy for enhancing collateral formation in hind limb ischemia model by using EPO transfected MSCs (MSC-EPO). Methods and Results: MSCs and MSCs-EPO were encapsulated into alginate microcapsules. Hind limb ischemia was induced by ligating and excising both the super facial femoral artery and vein in the left leg. The mice were implanted with either empty capsules, encapsulated 1 X 10 6 MSCs (MSC group), encapsulated 0.9 X 10 6 MSCs + 0.1 X 10 6 MSCs-EPO (low EPO group), or encapsulated 0.5 X 10 6 of MSC + 0.5 X 10 6 of MSCs-EPO (high EPO group). Blood analysis was performed on post-operative day (POD) 14 and 28 and histological evaluation with immunohistochemistry was performed on POD 14 (n=4/group). To evaluate the functional recovery, a spontaneous running wheel test was performed between POD 14 to POD 21. On POD 14, there was no significant change in hematocrit in 4 groups. On POD 28, the hematocrit in the high EPO group was significantly increased (57.2±4.6%) Histological evaluation revealed that the density of collateral vessels was increased in both the low and high EPO groups. (0.7±0.04, 0.84±005, 0.98±0.05 and 1.06±0.06 respectively) Although the high EPO group had a much higher density of collateral vessels, the running distance was significantly reduced to two third of the other groups.(6507±208.3, 6223±294.0, 6067±510.5 and 3952±322.1m/day, respectively) Conclusion: The use of alginate encapsulation of MSCs is a viable strategy for site directed gene therapy. Our data show that EPO can be effectively delivered resulting in an improvement in collateral vessel formation. However, chronic over-expression of EPO may cause adverse effects likley as a result of increased blood viscosity.

Postoperative Swallow Study as a Predictor of Intermediate Weight Loss after Sleeve Gastrectomy

Laparoscopic sleeve gastrectomy (LSG) is an accepted bariatric procedure. Swallow studies (SS) after LSG are not uniform and display different patterns with regard to contrast passage through the gastric sleeve. The impact of immediate postoperative contrast transit time on weight loss has not been studied. The influence of immediate fluid tolerance on weight loss after LSG is herein reported. Ninety-nine patients after LSG were included. There were 67 females, mean age 41 (range 17-67), mean BMI 44.4 (range 37-75). A routine SS was performed on postoperative day (POD) 1. Pattern of contrast transit was noted. Patients were followed-up in our bariatric clinic. Percent excess weight loss was significantly lower in the patients with rapid contrast passage (Group 1, n = 50) than those with delayed passage (Group 2, n = 49). Group 1 achieved 62, 58, and 53% at 1, 2, and 3years, respectively, while Group 2 attained 69, 74, and 75% at the same time points (p = 0.05, 0.001, and 0.04, respectively). Group 1 patients displayed a negative weight loss trend after 1year whereas Group 2 patients plateaued after 2years. Tolerance of fluid intake after LSG is crucial for patient recovery and discharge. Distinct radiologic appearance on POD 1 helps predict this behavior. Mid-term weight loss after LSG appears to be dependent on immediate postoperative contrast transit time, whereas patients with slow contrast passage tend to lose more weight. Long-term follow-up will reveal whether this finding will hold true.

Partial hepatectomy improves the outcome of intraportal islet transplantation by promoting revascularization

Revascularization of grafts is one of the important key factors for the success of islet transplantation. After partial hepatectomy, many growth factors such as hepatocyte growth factor and vascular endothelial growth factor are increased in the remnant liver. These growth factors have properties that promote angiogenesis. This might be an optimal environment for revascularization of islets transplanted intraportally. To verify this hypothesis, syngeneic islets (330 per recipient) were transplanted into the right hepatic lobes of streptozotocin-induced diabetic Balb/c mice with (hepatectomy group) or without (control group) left liver resection. Blood glucose was monitored for 28 d after transplantation. Glucose tolerance test was performed on post-operative day (POD) 30, and histological assessments were performed on POD 7 and 30 respectively. Analysis revealed that 36.7% of the control and 90.0% of the hepatectomy mice attained normoglycemia during the observation period (*p = 0.0142). Glucose tolerance was improved in the hepatectomy group (Area under the curve of intraperitoneal glucose tolerance tests on POD 30, Control; 47,700 ± 5,890 min*mg/dl, Hepatectomy; 26,000 ± 2,060 min*mg/dl: **p = 0.00314). Revascularization of grafted islets was more pronounced in the hepatectomy group (Vessel number per islet area on POD 7, Control; 3.20 ± 0.463 × 10−4/µm2, Hepatectomy; 7.08 ± 0.513 × 10−4/µm2: **p < 0.01). In the present study, partial hepatectomy (30%) improved the outcome of intraportal islet transplantation. Revascularization of islets transplanted into the liver may have been promoted by the induction of liver regeneration.