An anti-adhesive membrane containing a large amount of glycerin was developed for lung surgery and was tested in the pleural cavity of six dogs. The test membranes were put between the lung and the chest wound of the pleural cavity wall to separate them. In five of the animals, no adhesion was observed after 3 weeks in the area where the membrane had been inserted, but the area without the membrane showed firm adhesion between the lung and the pleural cavity wall. A sixth animal observed for 3 months also showed no adhesion. Seprafilm, which is the product of choice for peritoneal surgeries, was used as a control in six dogs. Seprafilm could not prevent adhesion in the pleural cavity of all six animals after 3 weeks observation. The new test membrane contained glycerin, which gathered and dispersed abundant water. Together with this, growth factors are also dispersed, resulting in dilution of excessive growth factors at the wound sites. In general, fibroblasts do not migrate in an extremely hydrous gel matrix. Migration of fibroblasts into the membrane is minimized, resulting in the prevention of formation of adhesion tissue composed of fibroblasts and collagen fibers. From the results, we assume that water can prevent adhesion after surgery.

Background We evaluated the change of cerebral regional tissue oxygen saturation (rSO 2 ) along with the pneumoperitoneum and the Trendelenburg position. We also assessed the relationship between the change of rSO 2 and the changes of mean arterial blood pressure (MAP), heart rate (HR), arterial carbon dioxide tension (PaCO 2 ), arterial oxygen tension (PaO 2 ), or arterial oxygen saturation (SaO 2 ). Methods Forty-one adult patients who underwent a robotic assisted endoscopic prostatic surgery under propofol and remifentanil anesthesia were involved in this study. During the surgery, a pneumoperitoneum was established using carbon dioxide. Measurements of rSO 2 , MAP, HR, PaCO 2 , PaO 2 , and SaO 2 were performed before the pneumoperitoneum (baseline), every 5 min after the onset of pneumoperitoneum, before the Trendelenburg position. After the onset of the Trendelenburg position, rSO 2 , MAP, HR were recorded at 5, 10, 20, 30, 45, and 60 min, and PaCO 2 , PaO 2 , and SaO 2 were measured at 10, 30, and 60 min. Results Before the pneumoperitoneum, left and right rSO 2 were 67.9 ± 6.3% and 68.5 ± 7.0%. Ten minutes after the onset of pneumoperitoneum, significant increase in the rSO 2 was observed (left: 69.6 ± 5.9%, right: 70.6 ± 7.4%). During the Trendelenburg position, the rSO 2 increased initially and peaked at 5 min (left: 72.2 ± 6.5%, right: 73.1 ± 7.6%), then decreased. Multiple regression analysis showed that change of rSO 2 correlated with MAP and PaCO 2 . Conclusions Pneumoperitoneum and the Trendelenburg position in robotic-assisted endoscopic prostatic surgery did not worsen cerebral oxygenation. Arterial blood pressure is the critical factor in cerebral oxygenation. Trial registration Japan Primary Registries Network (JPRN); UMIN-CTR ID; UMIN000026227 (retrospectively registered).

BackgroundGlobal brain ischemia-reperfusion during propofol anesthesia provokes persistent cerebral pial constriction. Constriction is likely mediated by Rho-kinase. Cerebral vasoconstriction possibly exacerbates ischemic brain injury. Because Y-27632 is a potent Rho-kinase inhibitor, it should be necessary to evaluate its effects on cerebral pial vessels during ischemia—reperfusion period. We therefore tested the hypotheses that Y-27632 dilates cerebral pial arterioles after the ischemia-reperfusion injury, and evaluated the time-course of cerebral pial arteriolar status after the ischemia-reperfusion.MethodsJapanese white rabbits were anesthetized with propofol, and a closed cranial window inserted over the left hemisphere. Global brain ischemia was produced by clamping the brachiocephalic, left common carotid, and left subclavian arteries for 15 min. Rabbits were assigned to cranial window perfusion with: (1) artificial cerebrospinal fluid (Control group, n = 7); (2) topical infusion of Y-27632 10−6 mol · L−1 for 30 min before the initiation of global brain ischemia (Pre group, n = 7); (3) topical infusion of Y-27632 10−6 mol · L−1 starting 30 min before ischemia and continuing throughout the study period (Continuous group, n = 7); and, (4) topical infusion of Y-27632 10−6 mol · L−1 starting 10 min after the ischemia and continuing until the end of the study (Post group, n = 7). Cerebral pial arterial and venule diameters were recorded 30 min before ischemia, just before arterial clamping, 10 min after clamping, and 5, 10, 20, 40, 60, 80, 100, and 120 min after unclamping.ResultsMean arterial blood pressure and blood glucose concentration increased significantly after global brain ischemia except in the Continuous group. In the Pre and Continuous groups, topical application of Y-27632 produced dilation of large (mean 18–19%) and small (mean; 25–29%) pial arteries, without apparent effect on venules. Compared with the Control and Pre groups, arterioles were significantly dilated during the reperfusion period in the Continuous and Post groups (mean at 120 min: 5–8% in large arterioles and 11–12% in small arterioles).ConclusionsY-27632 dilated cerebral pial arterioles during reperfusion. Y-27632 may enhance recovery from ischemia by preventing arteriolar vasoconstriction during reperfusion.

We evaluated the direct effects of Y-27632 on pial microvessels. Y-27632 dilates only pial arterioles in a concentration-dependent manner, and most at a concentration of 10(-5) mol l(-1). Y-27632 is a potent cerebral pial arteriolar dilator but is not a venular dilator.

Japan Primary Registries Network (JPRN); UMIN-CTR ID; UMIN000010640.