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111.
Hayato Sasaki Yoshiaki Murakami Kenichiro Uemura Takeshi Sudo Yasushi Hashimoto Naru Kondo Taijiro Sueda 《International surgery》2015,100(6):1084-1088
Postpancreatectomy hemorrhage is a potentially life-threatening complication. We report herein our experience with a 65-year-old man with locally advanced pancreatic adenocarcinoma who underwent pancreatoduodenectomy with lymphadenectomy following neoadjuvant chemoradiotherapy. On postoperative day 45, he developed massive hematemesis. Angiography revealed active bleeding from the common hepatic artery, and transcatheter coil embolization of that vessel was successfully performed. On postoperative day 64, he again developed massive hematemesis. Angiography revealed active bleeding from the proximal superior mesenteric artery. Immediately after coil embolization of that vessel, bypass grafting between the superior mesenteric artery and the right common iliac artery was performed, using a greater saphenous vein graft. The combination of embolization and bypass grafting is an option for treatment of bleeding from the superior mesenteric artery in an emergent situation.Key words: Superior mesenteric artery, Bleeding, Bypass, Pancreatoduodenectomy, Postpancreatectomy hemorrhagePostpancreatectomy hemorrhage (PPH) is a rare but life-threatening complication, often associated with the presence of a pancreatic fistula or intraabdominal abscess.1 The mortality associated with arterial bleeding after pancreatoduodenectomy is reportedly between 14.3% and 30.7%.2–6 With recent advances in interventional radiology techniques, transcatheter arterial embolization (TAE) has become an alternative to surgical treatment.3,5,7,8 However, it may be difficult to treat these patients with interventional radiology techniques alone, given their often unstable condition. In addition, the inappropriate use of TAE for arterial bleeding, especially after pancreatoduodenectomy, can lead to end-organ infarction and subsequent infection. We report herein our experience with a patient who had bleeding from the superior mesenteric artery (SMA) after pancreatoduodenectomy. This patient was successfully treated using SMA coil embolization followed by creation of an SMA-iliac artery bypass using a greater saphenous vein graft. 相似文献
112.
Cell-contracted collagen gels could provide rejection-free biomaterials for tissue engineering, but their application is limited by relatively low mechanical strength. We developed a special type I collagen construct (based on embedded fibroblasts) that was formed into a gel thread by using two anchors to constrain gel contraction in one direction. Each gel thread contained 2 mg of type I collagen and 1.0 x 10(6) fibroblasts, and had an initial volume of 3 mL. After 9 days in culture, this preparation was transformed into a thread-like construct measuring 26 x 2.3 x 0.21 mm. Investigation of the microstructure showed that the collagen fibrils longitudinally between two cells had most aligned with the direction of the constraint stress and had assumed higher density than those in the freely contracted controls. During culturing, the constraint stress first increased then decreased, with implications for the nature of the interaction between the embedded cells and collagen matrix. Under uniaxial tensile testing, the ultimate stress and material modulus increased by factors of 6 and 16, respectively, compared with controls, while the maximal strain decreased by 590%. Compared with the similar constructs in the literature, the thread gel was fabricated by means of a novel mold configuration so that it contracted to thread shape much faster, and more importantly, the constraint force was firstly reported in this article. The improved mechanical properties show that the gel thread could be an effective biomaterial for such tissue engineering applications as the fabrication of blood vessels, ligaments, and tendon grafts. 相似文献
113.
Mitsuru Takahashi Hidenobu Takahashi Tetsushi Itoh Masaharu Nomura Akihiko Ogata Sachio Maehara Harubumi Kato 《Annals of thoracic and cardiovascular surgery》2006,12(1):50-52
Postoperative empyema and aspergillosis were diagnosed in a 66-year-old man. Since non-operative therapy was not effective, we performed surgery. On the 8th postoperative day, a covered Ultraflex expandable stent (Boston Scientific, Galway, Ireland) was implanted to make a one-way airway for blocking a major air leak from a bronchopleural fistula causing respiratory distress. His general condition improved gradually, and he was discharged 30 days after stenting. In conclusion, we used a covered Ultraflex expandable stent to make an airway to block an air leak. This may be a new application for this stent. 相似文献
114.
Wakai T Shirai Y Tsuchiya Y Nomura T Akazawa K Hatakeyama K 《World journal of surgery》2008,32(6):1067-1074
BACKGROUND: This study aimed to define the role of combined major hepatectomy and pancreaticoduodenectomy in the surgical management of biliary carcinoma and to identify potential candidates for this aggressive procedure. METHODS: A retrospective analysis was conducted on 28 patients who underwent a combined major hepatectomy and pancreaticoduodenectomy for extrahepatic cholangiocarcinoma (n = 17) or gallbladder carcinoma (n = 11). Major hepatectomy was defined as hemihepatectomy or more extensive hepatectomy. Altogether, 11 patients underwent a Whipple procedure, and 17 had a pylorus-preserving pancreaticoduodenectomy. The median follow-up time was 169 months. RESULTS: Morbidity and in-hospital mortality were 82% and 21%, respectively. Overall cumulative survival rates after resection were 32% at 2 years and 11% at 5 years (median survival time 9 months). The median survival time was 6 months with a 2-year survival rate of 0% in 11 patients with residual tumor, whereas the median survival time was 26 months with a 5-year survival rate of 18% in 17 patients with no residual tumor (P = 0.0012). Residual tumor status was the only independent prognostic factor of significance (relative risk 4.65; P = 0.003). There were three 5-year survivors (two with diffuse cholangiocarcinoma and one with gallbladder carcinoma with no bile duct involvement) among the patients with no residual tumor. CONCLUSIONS: Combined major hepatectomy and pancreaticoduodenectomy provides survival benefit for some patients with locally advanced biliary carcinoma only if potentially curative (R0) resection is feasible. Patients with diffuse cholangiocarcinoma and gallbladder carcinoma with no bile duct involvement are potential candidates for this aggressive procedure. 相似文献
115.
Xie XQ Shinozawa Y Sasaki J Takuma K Akaishi S Yamanouchi S Endo T Nomura R Kobayashi M Kudo D Hojo N 《The Journal of surgical research》2008,146(2):298-303
BACKGROUND: Sepsis is an arginine-deficient state and is associated with overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). It has been indicated that low plasma levels of arginine are related to high mortality rates in sepsis. Arginine, however, is also known to be a precursor of NO. Therefore, administration of arginine in septic patients remains controversial. We examined the effects of co-administration of arginine and aminoguanidine, a selective iNOS inhibitor, on sepsis, using rat models. METHOD: Sepsis was induced in rats by cecal ligation and puncture (CLP). Effects of separate and combined administration of arginine and aminoguanidine were investigated by comparing plasma levels of arginine, expressions of heme oxygenase (HO)-1 and HO-2 in liver and lung, and nitrite + nitrate (NOx) excretion in urine, as well as neuroendocrine responses in urine in the early phase of sepsis. Seven-day survival rates were also examined. RESULTS: A combination of arginine and aminoguanidine recovered the plasma level of arginine at 6 h post-CLP, decreased expression of HO-1 in liver and lung at 24 h post-CLP, decreased urinary excretion of epinephrine, norepinephrine, dopamine, and 17-hydroxycorticosteroid in the first 24 h post-CLP, and increased 7-d survival. CONCLUSION: It is demonstrated that administration of arginine together with the selective iNOS inhibitor in the early phase of sepsis restores plasma arginine, reduces oxidative stress by probably maintaining NO derived from constitutive NOS, and attenuates neuroendocrine stress responses. This co-administration may be a beneficial treatment approach against sepsis. 相似文献
116.
BACKGROUND: Terminal warm blood cardioplegia, "Hot shot", is the method for providing an energy replenishment and/or early recovery of aerobic metabolism without electromechanical activity at initial reperfusion. The mechanism of beneficial effects of this Hot Shot is multifactorial. This study was designed to assess the effects of terminal warm blood cardioplegia by comparing with oxygenated terminal warm crystalloid cardioplegia. METHODS: In Group HS-B, n=8 (oxygenated blood; 37 degrees C, Ht: 20%, K+ 20 mEq/l, pH 7.237, PO2 219 mmHg) and in Group HS-C, n=8 (bloodless oxygenated (5% CO2+95%O2) crystalloid, 37 degrees C, K+ 20 mEq/l, pH 7.435, PO2 624 mmHg), terminal warm cardioplegia (20 ml/kg for 5 minutes) was studied in the isolated blood perfused neonatal lamb heart following 2 hr of cardioplegic ischemia. Another eight hearts served as control without any kind of terminal cardioplegia. After 60 min of reperfusion, LV function was measured. Coronary blood flow (CBF), oxygen content, and oxygen consumption (MVO2) were measured and the oxygen extraction ratio was calculated in Group HS-B and HS-C during terminal cardioplegia and/or reperfusion. Results are given as % recovery of preischemic values. RESULTS: HS-B as well as HS-C groups showed better functional recovery in maximum developed pressure (DP: 78.0+/-8.3 in HS-B vs 65.2+/-9.2%; p=0.018), maximum dp/dt (67.3+/-6.2 in HS-B, 65.3+/-7.4 in HS-C vs 55.8+/-5.0%; p=0.003, p=0.02), DP V10 (87.1+/-8.5 in HS-B vs 67.2+/-9.9%; p=0.0001), and peak dp/dt V10 (76.4+/-7.6 in HS-B, 69.8+/-8.1 in HS-C vs 58.6+/-6.9 %; p=0.0001) than the control group. Between the HS-B and HS-C groups, HS-B showed better functional recovery in terms of DP V10 (p=0.01). Oxygen delivery of terminal cardioplegia was almost four times higher in HS-B group (90.4+/-17.7 vs 18.7+/-1.1 mcl/ml), contrarily, HS-C group showed four times higher oxygen extraction ratio compared to HS-B group (0.78+/-0.06 vs 0.18+/-0.11), thus oxygen consumption during hot shot was maintained at the same level in both groups. CBF in the control group was lower than that in the other groups at 60 min of reperfusion. CONCLUSIONS: Reperfusion with both terminal warm cardioplegia including blood and oxygenated crystalloid cardioplegia resulted in better recovery of function and higher levels of CBF with slightly better function in terminal warm blood cardioplegia. 相似文献
117.
BACKGROUND: The inhibitory effect of allopurinol on calcium oxalate urolithiasis has been reported, but its effect on stone matrix proteins has not been studied in vivo. To clarify the effect of allopurinol on the matrix, we investigated its effect on the expression of osteopontin (OPN), which we previously identified as an important stone matrix protein. METHODS: Control rats were not treated. Rats of the stone group were given ethylene glycol (EG) and vitamin D(3), while the allopurinol groups (low-dose group and high-dose group) were treated with allopurinol in addition to receiving EG and vitamin D(3). RESULTS: The rate of renal stone formation was lower in the allopurinol groups than in the stone group. This was associated with a low expression of OPN mRNA in allopurinol-treated rats relative to that in the stone group. CONCLUSION: Allopurinol was effective in preventing calcium oxalate stone formation and reduced OPN expression in rats. Our results suggest that allopurinol prevents renal stone formation by acting against not only the control of oxalate but also OPN expression. 相似文献
118.
The risks and benefits of percutaneous nucleotomy for lumbar disc herniation. A 10-year longitudinal study 总被引:5,自引:0,他引:5
Mochida J Toh E Nomura T Nishimura K 《The Journal of bone and joint surgery. British volume》2001,83(4):501-505
Percutaneous nucleotomy is a relatively new technique for treating lumbar disc herniation. There is no agreement as to the volume of disc material to be removed. A long-term study of clinical and radiological data from patients treated by percutaneous nucleotomy was designed to identify the factors associated with favourable and unfavourable outcomes. We studied 42 patients for at least ten years; the mean follow-up was 10.9 years. They were divided into two subgroups to assess the value of preserving the nucleus pulposus in the central area of the disc. The overall success rate for both subgroups was 50%. A decrease in disc height on plain radiography and a decrease in signal intensity on MRI were observed more infrequently in patients in whom the nucleus pulposus in the central area of the disc had been preserved, than in those in whom it had been extensively removed. These adverse radiological findings correlated closely with increased low back pain during the first one to two years after operation and a poorer overall outcome. We conclude that percutaneous nucleotomy is most likely to be successful when the central area of the disc is preserved. 相似文献
119.
An 81-year-old female presented with a giant aneurysm of the distal anterior cerebral artery (A3) which grew from a small saccular aneurysm to a huge aneurysm within 36 months before manifesting as a mass lesion. The thrombosed portion of the aneurysm showed growth, whereas the aneurysmal cavity did not change in size. Computed tomography and magnetic resonance imaging showed new bleeding in the thrombosed portion. Hemorrhage into the thrombus and/or aneurysmal wall might have caused the aneurysmal growth. She refused surgery and was discharged with no deficits. Distal anterior cerebral artery aneurysm which shows neuroimaging signs of growth requires regular follow up as such lesions may become giant before manifesting clinical symptoms. 相似文献
120.
Kiyozo Morita Hiromi Kurosawa Koji Nomura Yoshihiro Ko Makoto Hanai Noriyasu Kawada Yokoh Matsumura Takahiro Inoue 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2001,49(4):207-215
OBJECTIVES: We conducted an acute experimental study to test the feasibility of dynamic cardiomyoplasty in a setting of modified Fontan procedure for univentricular heart with pulmonary hypertension to obtain a possible proxy for high-risk Fontan candidates. METHODS: After electrical preconditioning of the left latissimuss dorsi for 6 weeks in 8 dogs, the right ventricular cavity was totally obliterated with concomittent closure of the tricuspid valve and right pulmonary artery. Modified Fontan circulation was established with the aortic homograft anastomosed between the right atrium and pulmonary trunk, incorporated with a pericardial pouch as a compression chamber (neoright ventricle) fixed onto the epicardial surface of the ventricle. After cardiopulmonary bypass termination, a latissimus dorsi was applied to wrap the pericardial pouch and ventricle clockwise and stimulated with a trained-pulse (25 Hz) at 1:1 synchronization ratio with cardiac beats. RESULTS: Profound right heart failure was noted during Fontan circulation in increased pulmonary vascular resistance (11 +/- 3.2 Wood units), whereas graft pacing showed significant augmentation of systolic pulmonary pressure by 54 +/- 12%, the mean pulmonary flow by 68 +/- 23%, and aortic pressure by 23 +/- 5% at a physiological range of central venous pressure (13.2 +/- 0.7 mmHg). Right heart function curve analysis confirmed marked augmentation of right heart performance, restoring almost normal pulmonary circulation. These functional benefits were sustained up to 4 hours in 4 animals until experiments were terminated. CONCLUSIONS: Dynamic cardiomyoplasty in a modified Fontan procedure is a viable surgical option for univentricular heart, not a Fontan candidate. 相似文献