Sosuke Tadano

Effects of Platelet-Rich Plasma on Intestinal Anastomotic Healing in Rats: PRP Concentration is a Key Factor

BACKGROUND Few studies have examined the effects of platelet-rich plasma (PRP) on intestinal anastomotic healing. The applied preparation methods and PRP concentrations used in the few studies that have been carried out varied markedly. Therefore, the positive effects of PRP on the anastomotic healing process remain unclear. The aim of this study is to examine the effects of different concentrations of PRP on intestinal anastomotic healing. MATERIAL AND METHODS From SD rat blood, three different concentrations of plasma were prepared: high-concentrated PRP (H-PRP: platelet count 5 × 10(6)/mm(3)), low-concentrated PRP (L-PRP: 2 × 10(6)/mm(3)), and platelet-poor plasma (PPP). Male SD rats underwent proximal jejunal anastomosis and central venous catheterization. Rats were divided into four groups (n = 12 for each group): control, PPP, L-PRP, and H-PRP groups. Two types of PRP and PPP (0.21 mL) were applied to each anastomosis line, with the exception of the control group. Total parenteral nutrition (TPN) solutions were administered (151 kcal/kg/d). Five days after surgery, anastomotic bursting pressure (ABP) in situ and hydroxyproline concentration (HYP) in anastomotic tissue were evaluated. RESULTS The ABP values of control, PPP, L-PRP, and H-PRP groups were 171 ± 20, 174 ± 23, 189 ± 17, and 148 ± 25 mmHg, respectively. The HYP values of each group were 516 ± 130, 495 ± 123, 629 ± 120, and 407 ± 143 μg/g dry tissue. Compared with the other groups, the L-PRP group exhibited a significant increase in both ABP and HYP, while the H-PRP group exhibited a significant decrease in these two variables. As a result, L-PRP was considered to promote anastomotic wound healing, but H-PRP was considered to inhibit it. There was no significant difference between the PPP group and the control group. CONCLUSIONS PRP concentration plays a crucial role in the efficacy of PRP. PRP might exert positive effects on intestinal anastomotic healing in a dose-dependent manner up to a certain level, but adverse effects occur when it is highly concentrated. The essential PRP action appears to be driven by the platelets themselves.

Platelet dynamics in the early phase of postischemic liver in vivo.

BACKGROUND In liver surgery, ischemia/reperfusion injury occasionally leads to liver failure by activating Kupffer cells (KCs) and leukocytes. However, few reports have demonstrated a relationship between KCs and platelets in vivo. This study investigated the relationship between these cells using intravital microscopy. MATERIALS AND METHODS Male Wistar rats were divided into two groups: (1) KC+ group, receiving 1 mL saline; and (2) KC- group, intravenously injected with liposome-encapsulated dichloromethylene disphosphonate for elimination of KCs. At 48 h after administration, 20 min of total normothermic hepatic ischemia was induced. Rhodamine-6G-labeled platelets and sinusoidal alterations were monitored using intravital microscopy up to 120 min after reperfusion. P-selectin, accumulated leukocytes and morphological damage, and alanine aminotransferase were evaluated. RESULTS In the KC+ group, numbers of adherent platelets increased significantly within 30 min after reperfusion. Endothelial cells of sinusoids in which KCs were mainly located were destroyed and the sinusoids were significantly constricted after reperfusion. Conversely, in the KC- group, adherent platelets in sinusoids were suppressed, and sinusoidal perfusion, endothelial cell damage and serum alanine aminotransferase levels were significantly improved. P-selectin on sinusoidal endothelial cells was not observed up to 120 min after reperfusion in either group. CONCLUSIONS Adherent platelets appear to reflect activation of KCs and lead to leukocyte accumulation, resulting in sinusoidal perfusion disturbance and liver failure. Evaluation of adherent platelets in the microcirculation offers an important marker of hepatic injury.

Platelets prevent acute liver damage after extended hepatectomy in pigs

Background/PurposePlatelets develop tissue repair and promote liver regeneration. We investigated whether platelets prevented acute liver damage after extended hepatectomy in pigs.MethodsThrombocytosis was induced by the following two methods; afterwards 80% hepatectomy was performed in pigs. In the first method, the pigs received administration of thrombopoietin [TPO (+) group], and they were compared with a control group [TPO (−) group]. In the second method, the pigs received a splenectomy [Sp (+) group], and theywere compared with another control group [Sp (−) group]. Platelet counts, biochemical examination of blood, and histopathological findings of the residual liver were examined.ResultsSerum aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and total bilirubin (T-Bil) levels were significantly decreased in the thrombocytotic groups compared with the control groups in the early period after hepatectomy. In the histopathological findings, hemorrhagic necrosis with a bile plug was observed in the control groups, but this phenomenon was not observed in the thrombocytotic groups. On transmission electron microscopy, the sinusoidal endothelial lining was destroyed and detached into the sinusoidal space with enlargement of Disse’s spaces in the thrombocytotic groups, but these findings were not observed in the control groups.ConclusionAn increased number of platelets prevents acute liver damage after extended hepatectomy.

Early Postoperative Oral Intake Accelerates Upper Gastrointestinal Anastomotic Healing in the Rat Model

BACKGROUND In our previous study, we reported that early postoperative oral feeding accelerated upper gastrointestinal anastomotic healing in rats. To investigate its underlying mechanism, we performed in vivo and in vitro experiments. MATERIALS AND METHODS Rats that received proximal jejunal anastomosis were divided into four groups: the enteral nutrition (EN) group were fed via gastrostomy, the total parental nutrition (TPN alone) group were fed via a venous catheter, the TPN + saline group received an additional administration of normal saline solution via gastrostomy, and the TPN + water group received an additional administration of distilled water via gastrostomy. The anastomotic bursting pressure (ABP) and the hydroxyproline content of the anastomotic tissue were measured 5 d postoperatively. In an in vitro setting, the rat gastrointestinal fibroblasts were subjected to uniaxial stretching for 60 min, and the expression of type I and type III collagen mRNA was evaluated. RESULTS The ABP and hydroxyproline content in the EN group, the TPN + saline group, and the TPN + water group were significantly higher than those in the TPN alone group (ABP; 214.6 ± 42, 199.4 ± 36, and 187.3 ± 29 versus 149.5 ± 49 mmHg; P < 0.01, hydroxyproline; 63.5 ± 10, 67.8 ± 13, and 64.1 ± 14 versus 50.5 ± 12 μmol/g dry tissue; P < 0.01). The mRNA levels of type I and type III collagen were increased by stretch stimulation. CONCLUSIONS These results suggest that mechanical loading plays a key role in anastomotic healing. Further investigations are necessary to confirm this suggestion.

An Experimental Study on the Relationship Among Airway Pressure, Pneumoperitoneum Pressure, and Central Venous Pressure in Pure Laparoscopic Hepatectomy.

Objectives:To determine optimal settings for airway pressure (AWP), pneumoperitoneum pressure (PPP), and central venous pressure (CVP) in pure laparoscopic hepatectomy. Background:High PPP is often employed to control bleeding from the hepatic vein during pure laparoscopic hepatectomy; however, there is a risk of pulmonary gas embolism. We noted that decreases in AWP were often effective. Methods:After establishing carbon dioxide pneumoperitoneum in 6 male piglets and maintaining PPP at 25 mmHg, CVP was measured 3 times at each of 9 levels of airway pressure, which was increased in increments of 5 cmH2O from 0 to 40 cmH2O. CVP was measured in the same manner by maintaining PPP at 20, 15, 10, 5, and 0 mmHg, and in laparotomy. Correlation and regression analyses were performed among airway pressure, CVP, and pneumoperitoneum pressure. Results:Positive correlations were observed between AWP and CVP and between PPP and CVP (P < 0.001). Under high airway pressure, CVP was persistently higher than pneumoperitoneum pressure. Under low airway pressure, CVP did not increase or often decreased when PPP was higher than CVP. Conclusions:By increasing pneumoperitoneum pressure, bleeding from the hepatic vein cannot be controlled under high airway pressure, but can be controlled under low airway pressure. However, under low airway pressure, the risk of pulmonary gas embolism increases when PPP is higher than CVP. We consider that reducing AWP is also effective for controlling bleeding from the hepatic vein and safer than increasing pneumoperitoneum pressure.

The manner of the inflammation-boosting effect caused by acute hyperglycemia secondary to overfeeding and the effects of insulin therapy in a rat model of sepsis

BACKGROUND The aim of the study was to investigate both the inflammation-boosting effect and the metabolic stress induced by acute hyperglycemia secondary to overfeeding with excessive glucose infusion and the effects of insulin therapy on those events in a rat model of sepsis. MATERIALS AND METHODS Sprague-Dawley rats underwent cecal ligation and puncture (CLP) or sham operation. Preestablished continuous intravenous glucose infusion was initiated immediately after surgery. First, rats with CLP-inducing sepsis were divided into three groups on the basis of the target blood glucose (BG) levels: high glucose (HG) group (overfed, >300 mg/dL), moderate glucose group (moderate hyperglycemia, 200-300 mg/dL), and no glucose group (100-150 mg/dL). The sham group received the same glucose infusion as that of the HG group. BG and plasma interleukin (IL) 6 levels were monitored over time. All rats were sacrificed 9 h after surgery to evaluate lung histology and measure hepatic total glutathione and malondialdehyde contents. Based on the results, the high glucose and insulin (HI) group was added to septic groups as a model of insulin therapy, in which insulin with the same HG dose as that in the HG group was administered to maintain moderate hyperglycemia. RESULTS BG level in all groups remained in the preestablished target range throughout the experiment. Plasma IL-6 level in all septic groups increased in a time-dependent manner, whereas that in the sham group with moderate hyperglycemia hardly increased. Nine hours after CLP, plasma IL-6 level in the HG group rose to 7407.5 ± 1987.3 pg/mL, which was three times higher than that in the other septic groups. There was no significant difference among moderate glucose, no glucose, and HI groups, in which BG level remained constant at <300 mg/dL. The HG group showed the worst consequences of lung injury and oxidative stress in the liver, which were completely stable in HI group. CONCLUSIONS Acute severe hyperglycemia in critical illness might excessively boost the existing systemic inflammatory response in a threshold-based manner. Insulin therapy under overfeeding could strongly inhibit such a boosting effect and oxidative stress in the liver.

The impact of three-dimensional reconstruction on laparoscopic-assisted surgery for right-sided colon cancer

Introduction During laparoscopic-assisted colorectal surgery (LACS) for right-sided colon cancer patients, we performed three-dimensional (3D) surgical simulation to investigate vascular anatomy, including the ileocolic artery (ICA), right colic artery (RCA) and superior mesenteric vein (SMV). Aim We also used 3D imaging to examine the shortest distance from the root of the ileocolic vein (ICV) to the gastrocolic trunk (GCT). Material and methods We analyzed 46 right-sided colon cancer patients who underwent 3D-simulated LACS. We also examined a control group of 20 right-sided colon cancer patients who underwent LACS without 3D imaging. Patients who received such assessments were classified into the following two groups based on the vessel arrangement patterns of the ICA and SMV: the type A group, in which the ICA crosses anterior to the SMV, and the type B group, in which the ICA crosses posterior to the SMV. The shortest length from the root of the ICV to the GCT (D mm) was measured via 3D imaging. Patient characteristics and perioperative outcomes for these three groups were compared. Results The mean D mm for all cases was 29.2 ±5.21 mm. Mean D mm values for the type A and type B groups were 27.8 ±4.21 and 30.5 ±5.53 mm, respectively. Intraoperative blood loss was lower in the type A group (41.8 ±27.5 g) and the type B group (44.5 ±31.6 g) than that in the control group (86.8 ±27.5 g) (p = 0.013). Conclusions 3D imaging was useful for understanding anatomical relationships during LACS.

The Impact of Laparoscopic-assisted Colorectal Surgery Using 3-dimensional Reconstruction for Highly Obese Patients With Colorectal Cancer

Objectives: During laparoscopic-assisted colorectal surgery (LACS), precise recognition of the anatomic variations and relationships among tumor and vessels is required. However, in highly obese patients, it is more difficult to grasp the surgical anatomy due to the presence of dense mesenteric fat tissue. We utilized a 3-dimensional (3D) reconstructed image for preoperative simulation and intraoperative navigation for LACS. In this study, we examined the correlation between patient obesity and 3D-simulated perioperative outcomes. Materials and Methods: We retrospectively analyzed 124 patients who underwent LACS using 3D surgical simulation at Tsukuba Medical Center Hospital. We sequentially divided our cohort into 2 groups: patients with a low body mass index (BMI<25 kg/m2, n=60) and patients with a high BMI (BMI ≥25 kg/m2, n=64). Patient characteristics and perioperative outcomes, including conversion rate, postoperative complications, operating time, intraoperative blood loss, and length of postoperative hospital stay, were compared for these 2 groups. Results: There were no significant differences in patient background between the 2 groups. We found it more difficult to grasp the surgical anatomy, including vessel arrangement, for high-BMI patients than for low-BMI patients because of the dense mesenteric fat tissue in high-BMI patients. There were no significant differences between the 2 groups with respect to perioperative outcomes. Conclusions: The utilized reconstructed 3D images were useful for understanding anatomic relationships, including vessel arrangement, during LACS, particularly in highly obese patients.

Minimally invasive direct coronary artery bypass in a patient with combined severe coronary artery disease and pancreatic ductal adenocarcinoma

Treatment of severe coronary artery disease in patients with a malignancy is challenging. A 74-year-old man was presented in critical condition because of cardiac rupture after inferior myocardial infarction. Pericardiocentesis rescued the patient from shock. A pancreatic tumor, which was suspected to be malignant, was an incidental discovery on computed tomography (CT). Coronary artery angiography revealed severe stenosis of the left anterior descending (LAD) artery and moderate stenosis of the left circumflex (LCX) artery. Minimally invasive direct coronary artery bypass (MIDCAB) for the LAD artery was performed, and 3 months after the MIDCAB, the patient underwent distal pancreatectomy. Pathological evaluation revealed pancreatic ductal adenocarcinoma. Both surgical treatments were successfully performed and the postoperative course was uneventful. MIDCAB for the LAD artery prior to surgical tumor resection is an effective and reliable myocardial revascularization in patients with combined severe coronary artery disease and a malignancy.

Neutrophil-to-lymphocyte ratio (NLR) to predict the short-term and long-term outcomes of gastric cancer patients.

e15560Background: Preoperative NLR was well known as highly repeatable, cost-effective and widely available long-term postoperative prognostic marker of gastric cancer patients. However, the utilit...