Keigo Yasumasa

Carbon dioxide insufflation attenuates parietal blood flow obstruction in distended colon : Potential advantages of carbon dioxide insufflated colonoscopy

BackgroundBowel distention after colonoscopy has been considered as a cause of blood flow disturbance. Carbon dioxide (CO2), with its higher absorbability and vasodilating effect, may reduce parietal blood flow disturbance of distended colon when used for intraluminal insufflation instead of air. The purpose of this study was to assess parietal blood flow of the colon distended with intraluminal air/CO2 insufflation.MethodsA 5-cm segment of rat colon was insufflated with either air (air group) or CO2 (CO2 group). Two insufflation methods were employed: temporary insufflation up to an intraluminal pressure of 60 mmHg and continuous insufflation at a pressure of 5, 15, and 30 mmHg. Bowel distention and parietal blood flow measured by laser Doppler imaging were evaluated.ResultsFor temporary insufflation, bowel distention was prolonged in the air group, whereas it rapidly resolved in the CO2 group. Parietal blood flow decreased in both groups; however, it recovered within 5 min in the CO2 group. For continuous insufflation, under 5 mmHg insufflation, blood flow decreased in the air group, whereas it increased in the CO2 group. Blood flow decreased in both groups under 15 mmHg insufflation; however, it decreased less in the CO2 group. There was a reverse relationship between insufflation pressure and blood flow difference. Inhibition of nitric oxide synthase, ATP-sensitive K+ channel, or heme oxygenase was ineffective against a CO2-induced increase in blood flow.ConclusionCO2 insufflation preserved parietal blood flow not only by rapid resolution of bowel distention but also by its potential vasodilative effect.

Primary colorectal signet-ring cell carcinoma: Clinicopathological features and postoperative survival

PurposeThe objective of this study was to investigate the clinicopathological features and postoperative survival of primary colorectal signet-ring cell carcinoma.MethodsNineteen patients with primary colorectal signet-ring cell carcinoma were identified from a database of 5884 surgical patients with colorectal cancers treated surgically at Osaka University Hospital and affiliated hospitals between 1993 and 2007. The clinicopathological data of those patients were compared with those of 5792 patients with non-signet-ring cell colorectal carcinoma (5417 with well or moderately differentiated adenocarcinoma and 375 with poorly differentiated adenocarcinoma or mucinous carcinoma).ResultsAll patients showed a tumor depth of over T3. Lymph node involvement occurred in 14 patients. Seven of 19 patients presented with distant metastasis at the time of diagnosis. The overall 5-year survival rate in primary signet-ring cell carcinoma was significantly lower at 24.1%, in comparison to 77.5% in well or moderately differentiated adenocarcinoma and 57.7% in poorly differentiated adenocarcinoma or mucinous carcinoma. Likewise, the postoperative survival in Stage III was also significantly worse. On the other hand, no significant difference was observed in Stage II or IV.ConclusionThe most important feature of primary colorectal signet-ring cell carcinoma is the advanced stage at the time of diagnosis. In addition, the postoperative survival is worse than for other types of colorectal cancer.

A versatile dual-channel carbon dioxide (CO2) insufflator for various CO2)applications. The prototype.

BackgroundCarbon dioxide (CO2), with its rapid absorptive nature, has been proven superior to atmospheric air as an insufflating agent in various clinical settings. However, CO2 insufflation has not gained wide clinical acceptance, mainly because there has been no suitable feeding system. The authors therefore have developed a versatile “dual-channel” CO2 insufflator that facilitates wider use of CO2. The objectives of this study were to introduce the authors’ prototype insufflator, to evaluate its safety and performance, and to validate CO2 application using the prototype.MethodsThe prototype insufflator provides one CO2 inlet connected to a regular CO2 gas cylinder and two CO2 outlets positioned on the front and back of the device, respectively. The CO2 gas fed from the cylinder is pressure-regulated and divided into two independent conduits inside the device. The front outlet feeds CO2 gas for pneumoperitoneum at an electronically controlled pressure and flow rate. The back channel supplies CO2 gas at a fixed flow rate, allowing manual control of insufflation for various purposes. The device was evaluated with canine models.ResultsThe prototype was safe and performed well. The CO2 application (colonoscopy in this series) using the back channel was feasible while intact CO2 pneumoperitoneum was simultaneously maintained via the front channel. There were no device malfunctions. The serial abdominal x-rays indicated that intraluminal CO2 insufflation such as that used for CO2 colonoscopy caused less residual intestinal gas than conventional air insufflation.ConclusionsThe dual-channel CO2 insufflator enabled two different modes of CO2 insufflation at the same time from a single CO2 cylinder. The authors are now improving the prototype to allow safer and wider usage of CO2 in the operating room.

A Simple Application Technique of Fibrin-Coated Collagen Fleece (TachoComb) in Laparoscopic Surgery

A fibrin-coated collagen fleece (TachoComb, Nycomed, Denmark) is a powerful topical hemostatic agent, which has been aggressively used in conventional open surgery with a favorable clinical outcome. However, the use of TachoComb in laparoscopic surgery has not yet gained wide clinical acceptance, because a simple and well-functioning application system is not available. The authors have newly developed a quick, simple, and effective laparoscopic TachoComb application technique: housing a small strip of TachoComb in a rubber tube, then conveying it into the peritoneal cavity, and applying it using standard laparoscopic forceps. The repeated application of TachoComb strips is feasible and of practical value especially in laparoscopic surgery, since a small TachoComb never compromises either the application procedure or laparoscopic visualization.

Subcutaneous emphysema along cutaneous striae after laparoscopic surgery: a unique complication.

A case of postlaparoscopic subcutaneous emphysema developed along cutaneous striae was reported. A 35-year-old male patient with marked cutaneous striae underwent hand-assisted laparoscopic proctocolectomy for steroid-dependent ulcerative colitis. After an uneventful surgery, he developed subcutaneous emphysema, which was noted along the cutaneous striae in the bilateral thigh. The localization of emphysema suggested that Pfannensteil mini-laparotomy for hand access was most responsible for the development of subcutaneous emphysema.

A case of retroperitoneal liposarcoma after delivery with expression of estrogen receptor: Report of a case.

Highlights • Retroperitoneal liposarcoma related pregnancy is rare.• Liposarcoma is sometimes positive for hormone receptor.• Additional therapy for liposarcoma is important to improve prognosis.

Predicting prolonged hospital stay after laparoscopic cholecystectomy.

Widespread application of laparoscopic cholecystectomy (LC) has resulted in a high complication rate and leads to prolonged hospital stays. This study aimed to investigate the preoperative and intraoperative clinical factors that relate to prolongation of hospital stay.