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This study describes a novel technique for skeletonization and isolation of Glissonean and venous branches during liver surgery using a harmonic scalpel (HS). Hepatic resections with HS were performed with the skeletonization and isolation technique in 50 patients (HS group). Variables evaluated were blood loss, operative time, biliary leak, and morbidity. The results were compared with 50 hepatic resections that were performed using a previously established technique: Cavitron ultrasonic surgical aspirator with electric cautery, ligatures, and hemoclips (NHS group). The HS group had shorter total operative times (285 versus 358 minutes; P = 0.01), less blood loss (389 versus 871 mL; P = 0.034), and less crystalloid infusion (2744 versus 3299 mL; P = 0.027) compared with the NHS group. Postoperative liver function and complication rates were similar when comparing the two groups. These data demonstrate that HS is a simple, easy, and effective instrument for the skeletonization and isolation of vessels during liver transection.Key words: Liver resection, Ultrasonic scalpel, Skeletonization, Cavitation effectVarious devices are available for liver transection, but the availability of comparative data for transection techniques is limited by the diversity of operative procedures. Clamp crushing (CC) and a Cavitron ultrasonic surgical aspirator are widely used for splitting the liver parenchyma,1,2 and hemostasis is achieved by bipolar coagulation, ligatures, or hemoclips. Various coagulating devices, such as Ligasure,3 Tissuelink,4 and the Harmonic Scalpel (HS),57 have recently been developed to aid in liver splitting. The choice of instrument is often based on individual surgeon preference. Higami et al8,9 described a novel technique to skeletonize and harvest the internal thoracic artery with the HS, and the present study capitalizes on their experience to describe a unique method to skeletonize and isolate the Glissonean and venous branches using an HS.  相似文献   
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“Soft pancreas” has often been reported as a predictive factor for postoperative pancreatic fistula (POPF) after pancreatectomy. However, pancreatic stiffness is judged subjectively by surgeons, without objective criteria. In the present study, pancreatic stiffness was quantified using intraoperative ultrasound elastography, and its relevance to POPF and histopathology was investigated. Forty-one patients (pancreatoduodenectomy, 30; distal pancreatectomy, 11) who underwent intraoperative elastography during pancreatectomy were included. The elastic ratio was determined at the pancreatic resection site (just above the portal vein) and at the remnant pancreas (head or tail). Correlations between the incidence of POPF and patient characteristics, operative variables, and the elastic ratio were examined. In addition, the relationship between the elastic ratio and the percentage of the exocrine gland at the resection stump was investigated. For pancreatoduodenectomy patients, main pancreatic duct diameter < 3.2 mm and elastic ratio < 2.09 were significant risk factors for POPF. In addition, the elastic ratio, but not main pancreatic duct diameter, was significantly associated with the percentage of exocrine gland area at the pancreatic resection stump. Pancreatic stiffness can be quantified using intraoperative elastography. Elastography can be used to diagnose “soft pancreas” and may thus be useful in predicting the occurrence of POPF.Key words: Elastography, Exocrine gland, Pancreatectomy, Pancreatic stiffness, Postoperative pancreatic fistulaDespite current advances in surgical techniques, pancreatectomy is a very difficult procedure associated with the risk of multiple postoperative complications. The morbidity and mortality are reported to be 20–50% and 1–5%, respectively.1 In particular, a postoperative pancreatic fistula (POPF) can sometimes lead to life-threatening complications, such as hemoperitoneum and sepsis. The worldwide incidence of POPF is reported to be 5–50%. Several predictive factors for POPF have been reported to date, and, of these, “soft pancreas” has often been mentioned.24 However, in all of these reports, evaluation of pancreatic stiffness has depended on subjective judgment by the surgeon, without objective parameters as criteria.Elastography has recently been developed to enable real-time visualization of the relative stiffness of tissue elasticity, and its usefulness in various clinical disciplines for tumor diagnosis and differential diagnosis has been described.5 In gastroenterology, evaluation of liver fibrosis and diagnosis of pancreatic tumors and chronic pancreatitis using endoscopic ultrasound (EUS) have been reported,6,7 but the use of elastography in surgery has not been reported. An objective assessment of pancreatic stiffness as a predictive risk factor for POPF can help in choosing the intraoperative surgical technique and in planning the postoperative management strategy. Therefore, in the present study, pancreatic stiffness was quantified using intraoperative ultrasound elastography, and its relevance to POPF and histopathology was investigated.  相似文献   
945.
It is well known that host immunity plays an important role in the defense against colorectal cancer (CRC) progression. The effects of autoimmune diseases, such as rheumatic disease (RD) in which the immune system is deregulated, on this immunity have not been fully investigated. The medical records of 1299 consecutive patients diagnosed with primary colorectal cancer who underwent surgical resection were retrospectively reviewed. The clinicopathologic factors of 28 subjects with RD (RD group) were compared with those of 1271 patients without RD (non-RD group). Compared to the non-RD group, the RD group was typified by a predominance of females (P < 0.01), older age (P < 0.01), and a lower incidence of rectal cancer (P = 0.02). Although no difference was observed between the groups in terms of TNM classification, disease-free and overall survival were significantly poorer in the RD group in both univariate and multivariate analyses. Subjects who had RD for more than 10 years tended to have a higher frequency of lymph node metastasis (P = 0.06) and a significantly higher incidence of synchronous distant metastasis (P = 0.035) at the time of cancer diagnosis. RD was associated with a significantly poorer prognosis of colorectal cancer, suggesting that deregulation of the immune system by autoimmune diseases may adversely affect the host immune defense against colorectal cancer progression.Key words: Colorectal cancer, Rheumatic disease, Host immunity, PrognosisIt is well known that host immunity plays an important role in defenses against the development and progression of cancer. The degree of lymphocyte infiltration into tumors has been reported to correlate with improvements of patient survival.1 In carcinogen-induced mouse models of cancer, primary tumor susceptibility has been found to be enhanced in immunocompromised mice; conversely, the capacity for such tumors to grow after transplantation into wild-type mice is reduced.2,3 Although cancer cells originate from autologous normal tissue, the immune system can recognize even minimal cellular alterations, distinguish cancerous from normal cells, and elicit an immune response.In autoimmune diseases represented by rheumatic disease (RD), the immune system loses the ability to distinguish nonself from self, eliciting an immune response against self-antigens; in this process, there is a possibility that immune defenses against non-normal cells are lost or impaired, facilitating the development and progression of cancer. In addition, the development of RD associated with cancer has been reported, and as its development is dependent on the production of substances such as hormones, peptides, autocrine and paracrine mediators, and antibodies or the stimulation of cytotoxic lymphocytes, the condition is known as paraneoplastic rheumatic syndrome. In such cases, RD tends to be less responsive to therapy than its nonparaneoplastic equivalents, and instead, treatment of the underlying cancer usually results in regression of RD.4,5 Thus, it is postulated that RD and cancer are closely associated. However, only a few reports on the incidence and risk of cancer among patients with RD exist,6,7 and the characteristics and prognosis of colorectal cancer (CRC) in these patients remain to be elucidated.In the present study, we investigated the development of CRC in the background of an immunologic disorder caused by RD, with the hypothesis that patients with CRC and autoimmune diseases such as RD will have a poorer prognosis than those without RD, as a result of depressed antitumor immunity caused by immune system incompetence. Thus, we aimed to clarify the features and prognosis of CRC-associated RD, and for this purpose, we compared the clinicopathologic features of patients with CRC with or without underlying RD.  相似文献   
946.
Allogeneic blood transfusion (ABT) has been reported as a major risk factor for surgical site infection (SSI) in patients undergoing colorectal surgery. However, the association of ABT with SSI in patients undergoing abdominoperineal resection (APR) and total pelvic exenteration (TPE) still remains to be evaluated. Here, we aim to elucidate this association. The medical records of all patients undergoing APR and TPE at our institution in the period between January 2000 and December 2012 were reviewed. Patients without SSI (no SSI group) were compared with patients who developed SSI (SSI group), in terms of clinicopathologic features, including ABT. In addition, data for 262 patients who underwent transabdominal rectal resection at our institution in the same period were also enrolled, and their data on differential leukocyte counts were evaluated. Multivariate analysis showed that intraoperative transfusion was an independent predictive factor for SSI after APR and TPE (P = 0.004). In addition, the first–operative day lymphocyte count of patients undergoing APR, TPE, and transabdominal rectal resection was significantly higher in nontransfusion patients compared with transfusion ones (P = 0.026). ABT in the perioperative period of APR and TPE may have an important immunomodulatory effect, leading to an increased incidence of SSI. This fact should be carefully considered, and efforts to avoid allogeneic blood exposure while still achieving adequate patient blood management would be very important for patients undergoing APR and TPE as well.Key words: Colorectal cancer, Abdominoperineal resection, Surgical site infection, Allogeneic blood transfusion, Patient blood managementPostoperative surgical site infection (SSI) is one of the most frequent complications associated with various surgical procedures, and it results in adverse outcomes, including longer hospital stay, higher health care costs, and increased surgical mortality.1 It is one of the most frequent nosocomial complications, accounting for almost one fifth of all health care–associated infections.2 Colon surgery and rectal surgery are associated with higher SSI rates compared with most other abdominal procedures, with 5% to 25% of colon and rectal surgery patients developing incisional and organ/space SSI.35 Moreover, the incidence of overall SSI was reported to be higher in rectal surgery patients (17%–28%) than in colonic surgery patients (9%–23%),3,5,6 with especially higher overall SSI rates observed in patients undergoing abdominoperineal resection (APR; 12%–51%).79 These are attributed to the high infection rates of the perineal wound, reported to be as high as 21%.10 Thus, the incidence of SSI associated with APR should be the highest among the various abdominal operative procedures.Various risk factors for postoperative SSI in colorectal surgery were reported previously. Open surgery,1012 perioperative allogeneic blood transfusion (ABT),4,10,12 and prolonged operation time4,9 have been found to be risk factors for SSI in a number of studies. Although several preceding reports have investigated the risk factors for SSI associated with APR, the reported independent risk factors varied among the studies. Although a number of studies have reported on the role of ABT as a strong risk factor for incisional SSI in colorectal surgery,13,14 only one study has investigated on its relevance to the onset of incisional SSI after APR procedure; but this study failed to demonstrate a significant association. Presently, therefore, the role of ABT as a potential risk factor for incisional SSI in APR remains to be elucidated, and doing so will be very important for the implementation of measures to achieve patient blood management in this group of patients.In this study, we aimed to elucidate the risk factors for SSI in patients receiving APR, especially focusing on ABT.  相似文献   
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