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991.
We evaluated the minimum alveolar concentration of sevoflurane required to maintain the bispectral index below 50 in children. We studied 55 children, divided into 1‐year‐old, 2‐ to 4‐year‐old and 5‐ to 9‐year‐old groups and used Dixon's up‐and‐down method and probit analysis. In the 1‐year‐old group, the bispectral index values remained above 50, with the end‐tidal sevoflurane concentration reaching 4.0% or higher. The minimum alveolar concentration of sevoflurane for maintaining the bispectral index below 50 was significantly higher in the 2‐ to 4‐year‐old group (2.33%, 95% CI 2.25–2.57) than in the 5‐ to 9‐year‐old group (2.10%, 95% CI 1.94–2.25; p = 0.005). We conclude that assessing the depth of anaesthesia using bispectral index is unreliable in children aged < 2 years anaesthetised with sevoflurane.  相似文献   
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Bowel strangulation is a common disease and often requires an urgent operation. Our previous report showed that lactate concentration in the blood is a good predictive marker for emergency. However, the alteration in lactate levels during the course of bowel strangulation remains unclear. We have investigated the progressive increase of lactate after induction of bowel strangulation with animal experiments. Thirty-six mice were randomly divided into 6 groups: 0, 8, 16, 24, 48, and 72 hours after operation. Under anesthesia, laparotomy was performed and a 5-cm segment of terminal ileum with the mesenteric artery and veins was ligated to create a strangulation obstruction. After operation, the arterial blood was collected and lactate concentration and pH were measured using a blood gas analyzer. Lactate concentration in the 8-hour group was markedly increased, while pH decreased significantly (P < 0.05). Lactate concentrations were kept at a high level from 8 to 72 hours after operation. The time lag between strangulation and an increase of lactate is 8 hours. Our study is the first report of a bowel strangulation mouse model. Therefore, it would be possible to find a more specific marker of bowel strangulation using our experimental model.Key words: Bowel strangulation, Lactate, Blood gas analyzer, Animal modelBowel strangulation is a common but very serious condition. Although some patients of it can be cured with a safe nonoperative management, others require an emergent operation. Therefore, an accurate and prompt diagnosis is important to consider an effective therapeutic strategy. Several studies have proposed predictive factors including acidosis and serum concentrations of creatine phoshokinase, lactic dehydrogenase, and amylase.13 Nonetheless, the early detection of bowel strangulation is often difficult, and reliable diagnostic information that may suggest its presence is required in clinical practice.Lactate is a product of anaerobic metabolism of glucose, and its concentration in the arterial blood is a good indicator of the severity of metabolic acidosis secondary to tissue hypoperfusion. The time needed to normalize the serum lactate levels is an important prognostic factor for survival.47 In ischemia associated with bowel strangulation, anaerobic metabolism causes an increase in the concentrations of lactate. We previously reported that lactate concentration is a good predictive factor for strangulation obstruction.8However, the alterations of lactate concentration during the course of bowel strangulation remain unclear. In order to reveal various pathophysiological changes, including the alterations of lactate concentration after bowel strangulation, it is very profitable to develop a novel animal model, especially with a genetically controlled mouse. In the present study, the arterial blood was obtained from mice at designated times after they had undergone a procedure to cause the closed loop obstruction, and pH and lactate concentrations in it were measured by using a blood gas analyzer. We focused on the progressive increase of lactate during first 72 hours after induction of bowel strangulation.  相似文献   
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Laparoscopic appendectomy is now widely practiced for the treatment of acute appendicitis. As result of increased demand for minimally invasive surgery, single-incision access was introduced and is being performed in various abdominal surgeries. Conventional laparoscopic appendectomy (LA) is gradually being performed in pregnant women. A 33-year-old woman was referred to our department at 39 weeks and 1 day of gestation due to abdominal pain. She was aware of her gastroepiploic pain even after the delivery. Though it was past 2 days, she was not recovering from right lower abdominal pain, so she was transferred to the Department of Gynecology at our hospital on the same day. Although an antibiotic was administered, the right abdominal pain did not improve, and she was referred to our department from the Department of Gynecology. We performed single-port LA (SP-LA). The total operation time was 63 minutes, and the estimated blood loss was 0 mL. She was discharged with no complications on postoperative day 7. We report our initial experience with single-port LA (SP-LA) using the glove technique for treatment of acute appendicitis in a postpartum woman. SP-LA using the glove technique was performed successfully during the puerperium without prolongation of operation time. This approach is less invasive, offers a much better cosmetic result than with conventional methods, and can be performed safely and at low cost.Key words: PLA (single-port laparoscopic appendectomy), PuerperiumThe advantages of laparoscopic appendectomy (LA) over open appendectomy (OA) are widely known and include decreased pain, shorter convalescence, and earlier return to work. Especially, LA is advantageous for treating acute appendicitis in pregnant women. Because the appendix of a pregnant woman is shifted from its normal position, OA may leave a larger operative scar than normal. In recent years, efforts of laparoscopic surgeons have resulted in a reduction in both the diameter of the access ports and the number of ports needed.1 In addition, natural orifice transluminal endoscopic surgery (NOTES) is being developed as another form of minimally invasive surgery.2 As a part of this process, the single-incision laparoscopic surgery (SILS) technique is presently being developed for various laparoscopic surgeries.3 SILS is a virtually scarless technique in which the single-port access site is hidden in the umbilicus. We think that the primary advantage of single-port laparoscopic appendectomy (SP-LA) is the superior cosmetic result compared with multi-port access LA. We report a very rare case in which SP-LA was performed to treat acute appendicitis during the puerperium. This approach is less invasive, offers a much better cosmetic result than with conventional methods, and can be performed safely and at low cost.  相似文献   
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A 61-year-old female was admitted to our hospital with epigastric pain and fever. The laboratory data showed severe inflammatory reactions. Computed tomography revealed an irregular tumor in the left hepatic lobe and swelling of lymph nodes. 18F-fluorodeoxy-glucose positron emission tomography (FDG-PET) showed high uptake by the tumor, with diffuse uptake in the spine. Based on the elevated leukocyte count and FDG-PET findings, the patient was diagnosed with a granulocyte colony-stimulating factor (G-CSF)-producing tumor (G-CSF, 213 pg/mL). We performed left trisegmentectomy of the liver, bile duct resection, and lymph node dissection. Histologically, the tumor was a poorly differentiated adenocarcinoma with some lymph nodes metastasis. Immunohistochemical staining of the tumor cells was positive for G-CSF. Therefore, the tumor was diagnosed as G-CSF–producing cholangiocellular carcinoma. The inflammatory reactions and serum G-CSF level transiently improved immediately after surgery. However, 1 month later, the leukocyte count and serum G-CSF level increased again, and recurrence was observed in the remnant liver. The patient died 3 months after the operation. G-CSF–producing cholangiocellular carcinoma is rare. This tumor progresses rapidly, and surgical treatment for advanced condition should be carefully selected.Key words: Granulocyte colony-stimulating factor, Cholangiocellular carcinoma, FDG-PET, Immunohistochemistry, LeukocytosisGranulocyte colony-stimulating factor (G-CSF)-producing tumors were first reported in 1977.1 G-CSF-producing cholangiocellular carcinomas (CCCs) are rare, with only 5 other reported cases. We herein report a surgical case of G-CSF–producing CCC with early recurrence and include bibliographic comments.  相似文献   
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