The influence of blood on the efficacy of intraperitoneally applied phospholipids for prevention of adhesions

<p>Abstract</p> <p>Background</p> <p>The formation of adhesions following abdominal surgery is a well known problem. In previous studies we demonstrated the efficacy and safety of intraperitoneally applied phospholipids in order to prevent adhesion formation. This study evaluates the influence of blood on the efficacy of intraperitoneally applied phospholipids for prevention of adhesions.</p> <p>Methods</p> <p>In 40 Chinchilla rabbits adhesions were induced by median laparotomy, standardized abrasion of the visceral and parietal peritoneum in defined areas of the ventral abdominal wall and the caecum. The animals were randomly divided into four groups. They received either phospholipids 3.0% or normal saline (NaCl 0,9%) (5 ml/kg body weight). In 50% of the rabbits we simulated intraperitoneal bleeding by administration of blood (1,5 ml/kg body weight). The other half served as control group. Ten days following the operation the animals were sacrificed and adhesion formation was assessed by computer aided planimetry and histopathologic examination.</p> <p>Results</p> <p>The median adhesion surface area in the NaCl-group (n = 9) amounted to 68,72 mm², in the NaCl+Blood-group (n = 10) 147,68 mm². In the Phospholipid (PhL)-group (n = 9) the median adhesion surface area measured 9,35 mm², in the PhL+Blood-group (n = 9) 11,95 mm². The phospholipid groups had a significantly smaller adhesion surface area (p < 0.05).</p> <p>Conclusion</p> <p>Again these results confirm the efficacy of phospholipids in the prevention of adhesions in comparison to NaCl (p = 0,04). We also demonstrated the adhesion preventing effect of phospholipids in the presence of intraperitoneal blood.</p

Different tissue reaction of oesophagus and diaphragm after mesh hiatoplasty. Results of an animal study

<p>Abstract</p> <p>Background</p> <p>Laparoscopic mesh-reinforcement of the hiatal region in the treatment of gastroesophageal reflux disease (GERD) and paraesophageal hernia (PEH) reduces the risk of recurrence. However, there are still controversies about the technique of mesh placement, shape, structure and material. We therefore compared tissue integration and scar formation after implantation of two different polypropylene-meshes in a rabbit model.</p> <p>Methods</p> <p>A total of 20 female chinchilla rabbits were included in this study. Two different meshes (Polypropylene PP, Polyglecaprone 25 Composite PP-PG) were implanted on the abdominal diaphragm around the oesophagus. After 3 months the implanted meshes were excised en-bloc. Histological and morphological analyses were carried out accordingly proliferation rate, apoptosis and collagen type I/III ratio.</p> <p>Results</p> <p>Regarding proliferation rate of oesophagus PP (9.31 ± 3.4%) and PP-PG (13.26 ± 2.54%) differ in a significant (p = 0.0097) way. In the diaphragm we found a significant (p = 0.00066) difference between PP (9.43 ± 1.45%) and PP-PG (18.73 ± 5.92%) respectively. Comparing oesophagus and diaphragm we could prove a significant difference within PP-PG-group (p = 0.0195). Within PP-group the difference reached no statistical significance (p = 0.88). We found analogous results regarding apoptosis.</p> <p>Furthermore, there is a significant (p = 0.00013) difference of collagen type I/III ratio in PP-PG (12.28 ± 0.8) compared to PP (8.44 ± 1,63) in case of oesophageal tissue. Concerning diaphragm we found a significant difference (p = 0.000099) between PP-PG (8.85 ± 0.81) and PP (6.32 ± 1.07) as well.</p> <p>Conclusion</p> <p>The histologic and morphologic characteristics after prosthetic enforcement of the hiatus in this animal model show a more distinct tissue integration using PP-PG compared to PP. Additionally, different wound healing and remodelling capability influence tissue integration of the mesh in diaphragm and oesophagus.</p

Reduction of peritoneal carcinomatosis by intraperitoneal administration of phospholipids in rats

<p>Abstract</p> <p>Background</p> <p>Intraperitoneal tumor cell attachment after resection of gastrointestinal cancer may lead to a developing of peritoneal carcinosis. Intraabdominal application of phospholipids shows a significant decrease of adhesion formation even in case of rising tumor cell concentration.</p> <p>Methods</p> <p>In experiment A 2*10⁶colonic tumor cells (DHD/K12/Trb) were injected intraperitonely in female BD-IX-rats. A total of 30 rats were divided into three groups with treatments of phospholipids at 6% or 9% and the control group. In experiment B a total of 100 rats were divided into ten groups with treatments of phospholipids at 9% and the control group. A rising concentration of tumor cells (10,000, 50,000, 100,000, 250,000 and 500,000) were injected intraperitonely in female BD-IX-rats of the different groups. After 30 days, the extent of peritoneal carcinosis was determined by measuring the tumor volume, the area of attachment and the Peritoneal Cancer Index (PCI).</p> <p>Results</p> <p>In experiment A, we found a significant reduction (control group: tumor volume: 12.0 ± 4.9 ml; area of tumor adhesion: 2434.4 ± 766 mm²; PCI 28.5 ± 10.0) of peritoneal dissemination according to all evaluation methods after treatment with phospholipids 6% (tumor volume: 5.2 ± 2.2 ml; area of tumor adhesion: 1106.8 ± 689 mm²; PCI 19.0 ± 5.0) and phospholipids 9% (tumor volume: 4.0 ± 3.5 ml; area of tumor adhesion: 362.7 ± 339 mm²; PCI 13.8 ± 5.1). In experiment B we found a significant reduction of tumor volume in all different groups of rising tumor cell concentration compared to the control. As detected by the area of attachment we found a significant reduction in the subgroups 1*10⁴, 25*10⁴and 50*10⁴. The reduction in the other subgroups shows no significance. The PCI could be reduced significantly in all subgroups apart from 5*10⁴.</p> <p>Conclusion</p> <p>In this animal study intraperitoneal application of phospholipids resulted in reduction of the extent of peritoneal carcinomatosis after intraperitoneal administration of free tumor cells. This effect was exceptionally noticed when the amount of intraperitoneal tumor cells was limited. Consequently, intraperitoneal administration of phospholipids might be effective in reducing peritoneal carcinomatosis after surgery of gastrointestinal tumors in humans.</p