摘要:

7 healthy pigs, anesthetized with ketamine/azaperon/thiopen tone and ventilated with O2/N2O by volume control, underwent anterior resection of the descending colon by laparoscopic view. During operation a pneumoperitoneum by inflating CO2 to an abdominal pressure of 14 mm Hg was installed Immediately (+2 min) after the onset of insufflation, both systemic and pulmonary arterial pressure increased. However, pulmonary artery pressure started to decrease after 10 min. whereas systemic arterial pressure remained elevated until the end of the experimental protocol. Left ventricular (LV) pressure and LV dp/dt increased in parallel with the systemic arterial pressure. Peak inspiratory pressure and central venous pressure increased in parallel with the abdominal pressure. Blood gas analysis of arterial and pulmonary blood demonstrated increased pCO2 associated with mild acidosis. Arterial pO2 did not change significantly indicating that the decreased pulmonal distensibility did not endanger the oxygenation. Pulmonary pO2 and pulmonary O2 saturation increased early (+10 min) after start of insufflation and were stable during the 2 h of observation indicating either increased cardiac output or decreased O2 extraction. We conclude that the sharp initial rise of both arterial pressures could be the effect of a mechanical action, whereas sustained hemodynamic alterations would involve complex regulatory mechanisms like an increase of sympathetic activity, baroreceptor control, or a response to acidosis. The acute and, in the systemic circulation, stable increase of ventricular afterload should be considered in patients with underlying cardiac diseases such as ischemic heart disease or valvular dysfunction or in patients taking drugs which interfere with normal compensatory processes.

ISSN:0014-312X    

DOI:10.1159/000129312

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Nitric oxide (NO), an endothelium-derived relaxing factor (EDRF), is released by different types of cells under the influence of endotoxin and various cytokines: a causative role of endothelium-derived NO in the endotoxin-induced hypotension has thus been suggested. To test the hypothesis that NO may be involved in the acute hypotension following endotoxin challenge, we administered a competitive inhibitor of NO synthase, L-N-monomethylarginine (L-NMMA) to anesthetized dogs in the presence and absence of endotoxin. Dogs were randomly allocated to three groups. Group 1 (n = 3) was given Escherichia coli endotoxin (3 mg/kg, i.v.), group 2 (n = 3) was given L-NMMA (5 mg/kg, i.v. bolus) 15 min after endotoxin and group 3 (n = 3) was given L-NMMA only. One additional dog was given L-arginine (100 mg/kg, i.v. bolus) after L-NMMA and endotoxin to reverse the inhibition of NO synthase. In each animal, saline was infused intravenously throughout the experiment to restore and maintain pulmonary artery occluded pressure at baseline level. After L-NMMA, the increases in mean arterial pressure were similar in group 2 (from 55 ± 18 to 75 ± 15 mm Hg, p < 0.01) and in group 3 (from 107 ± 27 to 128 ± 24 mm Hg, p < 0.01). Systemic vascular resistance increased from 2,994 ± 72 to 3,658 ± 673 dyn·s·cm–5 (p < 0.01) in group 3. Group 1 had lower plasma lactate levels than group 2 (3.5 ± 2.3 ± vs. 2.0 ± 1.6 mEq/l, p < 0.05). These results do not support the hypothesis that the early hemodynamic alterations following administrations of bacterial endotoxin are mediated by NO. Nevertheless, inhibition of NO synthesis may improve oxygen utilization early in end

ISSN:0014-312X    

DOI:10.1159/000129313

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0014-312X    

DOI:10.1159/000316394

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The relationship between portal hemodynamics and the energy metabolism of the liver with acute hepatic venous occlusion (HVO) was investigated by assessing the changes in the hepatic blood flow, arterial blood ketone body ratio (AKBR) and adenylate energy charge potential (ECP) of the liver tissue in canine model. Acute HVO was induced by the ligation of both the supra- and infrahepatic inferior vena cava (IVC) over the protruding ends of a heparin-coated polyethylene cannula inserted into the IVC. All dogs with only HVO (n = 5) died within 30 min. HVO dogs with additional mesocaval (MC) shunt (n = 10) survived longer than 7 days, during which time their AKBR were maintained in the normal range (over 1.0). ECP was also maintained above the normal level (over 0.850) during the 28-day period. Along with increasing portal pressure caused by the narrowing of the shunt anastomosis, the hepatic blood flow decrease gradually, resulting in a sudden decrease in AKBR and ECP when the portal pressure increased over 11 mm Hg. It is suggested that the normalization of portal pressure is one of the most important factors for maintaining the hepatic energy metabolism and that MC shunt is an effective therapy for maintaining the function of the liver with HVO, as long as portal pressure can be kept within normal range.

ISSN:0014-312X    

DOI:10.1159/000129314

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0014-312X    

DOI:10.1159/000316395

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Anterior gastric wall stapling combined with posterior truncal vagotomy has been used as a new and adequate gastric acid output-reducing procedure. Severing the posterior vagal trunk as well as stapling the anterior gastric wall could impair gastric emptying. In this study, the gastric emptying rate for solid food, using a radionuclide technique, has been evaluated in 2 series of canine experiments. Compared to the results after conventional highly selective vagotomy, a temporary delay in the gastric emptying rate could be found after this new procedure, however, completely normalizing 1 year later.

ISSN:0014-312X    

DOI:10.1159/000129315

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0014-312X    

DOI:10.1159/000316396

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The influence of deteriorated liver function on the healing process of arterial anastomosis was investigated in rats who underwent arterial reconstruction by the microscopic surgical techniques of conventional sutured vascular anastomosis (CSVA) and laser-assisted vascular anastomosis (LAVA). After 70% hepatectomy, the arterial ketone body ratio, reflecting the hepatic mitochondrial redox state, and the adenylate energy charges of the platelets, polymorphonuclear leukocytes and mononuclear cells, which play an important role in wound healing, were significantly lower in hepatectomized rats than in control. Tensile strength and bursting pressure with CSVA at the abdominal aortic anastomosis were also significantly lower in hepatecomized rats than in control. While CSVA was superior to LAVA in tensile strength, bursting pressure and incidence of aneurysm formation in nonhepatectomized rats, LAVA tended to show a lower degree of disadvantage in hepatectomized rats than CSVA, especially in the incidence of calcification at the anastomotic site. It was concluded that LAVA would be a useful option in vascular anastomosis, even during extended hepatectomy.

ISSN:0014-312X    

DOI:10.1159/000129316

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0014-312X    

DOI:10.1159/000316397

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We have assessed the macrophage response to polypropylene mesh (Marlex®) implanted into the abdominal wall of New Zealand white rabbits, using RAM-11 a monoclonal antibody specific for rabbit macrophages. The response diminishes during the course of the first 90 days after implantation, although the presence of other cell tpyes typical of foreign-body reactions increases. We have also confirmed the high degree of integration of the biomaterial into the wall achieved after 9 weeks. This has been determined using light and scanning electron microscopy. Likewise, we have observed the formation of numerous adhesions between the polypropylene mesh and the viscera of the abdominal cavity

ISSN:0014-312X    

DOI:10.1159/000129317

出版商:S. Karger AG    

年代:1994

数据来源: Karger