Intestinal fatty acid-binding protein (I-FABP) as biomarker of ischemic damage in experimentally induced 12-h small bowel obstruction.

Laboratory tests have low diagnostic specificity for strangulated intestinal obstruction. The diagnostic potential of the intestinal fatty acid-binding protein (I-FABP) expressed in the tips of the intestinal villi continues to be explored. The number of white blood cells, blood plasma levels of L-lactate, C-reactive protein (CRP) and I-FABP were measured in rats with experimentally induced 12-h strangulated and non-strangulated intestinal obstruction. The results of the laboratory tests were compared with the changes in the morphology of the intestinal wall. The studied diagnostic markers, except for CRP, were elevated by 12-h L-lactate and I-FABP concentrations were significantly higher in the strangulated obstruction group than in other groups. L-lactate (cutoff value: 3.01 mmol/L) had 86.1% sensitivity and 66.7% specificity for strangulated obstruction (AUC 0.815, p < 0.001). I-FABP levels above 5.432 ng/ml indicated strangulated obstruction with 83.33% sensitivity and 88.9% specificity (AUC 0.906, p < 0.001). Villi destruction was observed at 2 h in the strangulated obstruction group. I-FABP levels peaked at 4 h and plateaued at 12 h. Functional changes were observed in the non-strangulated group; they were accompanied by a significant increase in I-FABP concentrations that lasted until 12 h. Compared with traditional diagnostic markers of strangulated intestinal obstruction, I-FABP demonstrated higher accuracy in the first 12 h, although its concentrations reached the plateau already at 4 h and did not increase thereafter. The functional changes in small bowel wall in non-strangulated obstruction were accompanied by continuous increase in I-FABP concentrations up to 12 h, which may have influenced the diagnostic accuracy of the marker.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.

Adhesion prevention comparing liquid and solid barriers in the rabbit uterine horn model.

OBJECTIVE: The purpose of this study was to assess the ability of four different either solid or fluid barriers to reduce adhesions in an established model of gynecological surgery. STUDY DESIGN: 50 Chinchilla rabbits underwent bilateral deperitonealization and devascularization of the uterine horns (DUH). Afterwards solid membranes of either hyaluronic acid-carboxymethylcellulose (HA-CMC) or lactide-caprolactone-copolymer (LCC) were placed around the injured uterine horns or fluids (icodextrin (ID) or phospholipids (PL)) were intraperitonealy administered. The control group went without protection. After 10 days, adhesions were measured by planimetry. RESULTS: Phospholipids (median 49.8 mm2) significantly reduced adhesion areas in comparison to all other groups: surgical controls (median 230.6 mm2), HA-CMC (median 194.9 mm2), LCC (median 327.1 mm2), and icodextrin (median 242.1 mm2). CONCLUSIONS: These results prove the efficacy of phospholipids to reduce primary adhesion formation in the Chinchilla double uterine horn model compared to HA-CMC, LCC and icodextrin. Future clinical studies are recommended.

Tension banding closure of laparotomies: results of an experimental study in dogs.

BACKGROUND: Conventional laparotomy closure may cause ischemia, edema, and necrosis of the incisional edges, weakening of the tissue, and incisional hernia formation. Two experimental closure techniques were established to investigate laparotomy healing without suturing the incisional edges. METHODS AND MATERIALS: In 24 dogs median laparotomies were closed applying two techniques following the principle of tension banding. Investigations after 3, 9, and 15 months were laparoscopy, tensiometry, light and electron microscopy and measurement of collagen fibril diameters. RESULTS: Incisions healed without incisional hernias with only minimal adhesion formation. At all time points the tensile strength after the bridging technique (BT) did not differ significantly from that in the control group. Mean tensile strength after BT was higher than after the onlay technique (OT) at all time points but did not reach statistical significance. After 3 months the incisions after OT were significantly weaker than the control group. At all time points fibril diameters after OT were significantly smaller than in the control group. After 3 and 9 months the fibril diameters after OT were significantly smaller than after BT. Incisions healed with little scar formation in spite of a chronic inflammatory reaction. This reaction was more pronounced after OT and made access to the fascia difficult after 3 months. Both techniques led to early postoperative seroma formation. CONCLUSIONS: Applying the principle of tension banding, laparotomies healed without suturing the incisional edges. The effect of foreign material on the ultrastructure of regenerating tissue in direct contact to the incisional region was demonstrated by the OT, in which chronic inflammation disturbed the adequate formation of collagen. Further development of both techniques might allow laparotomy closure according to the physiological requirements of wound healing.

Phospholipids reduce adhesion formation in the rabbit uterine horn model.

OBJECTIVE: To access the ability of intraperitoneal phospholipids to reduce adhesions in a standardized model for gynecologic operations. DESIGN: A randomized, experimental, blinded study using the double uterine horn model. SETTING: Academic animal research laboratory. ANIMAL(S): Thirty-three Chinchilla rabbits. INTERVENTION(S): Phospholipids or Ringer's lactate were intraperitoneally administered after bilateral uterine horn injury. MAIN OUTCOME MEASURE(S): After 10 days, adhesions were evaluated concerning area and strength as well as scores describing tenacity and degree. RESULT(S): Phospholipids (median 102.1 mm2) significantly reduce adhesion areas in comparison to surgical controls (median 392.2 mm2) and Ringer group (median 323.8 mm2). Scores reflecting severity and degree of adhesions support this finding. CONCLUSION(S): These results prove the efficacy of phospholipids in the double uterine horn model. Future clinical studies are recommended.

Influence of early drainage of intraperitoneal phospholipids on efficacy of adhesion prevention.

Postoperative peritoneal adhesions impose a long-term risk of morbidity and mortality. Adjunctive means are needed to prevent these complications. In previous studies we could demonstrate the efficacy and safety of intraperitoneally applied phospholipids with regard to adhesion prevention and wound healing, respectively. The assumption is that phospholipids rapidly adhere to the peritoneal surface and to the mesothelial lesions. This study was designed to evaluate the influence of early drainage of the administered fluid volume on the control of adhesion formation. Forty chinchilla rabbits underwent median laparotomy and standardized abrasion of circumscript areas of the ventral abdominal wall, the cecum, and the ileum. The animals randomly received either 75 mg/kg body weight of phospholipids in a volume of 5.0 mL/kg body weight (n = 20) or the same volume of Ringer's lactate solution (n = 20) prior to closing the laparotomy wounds. In 50% of the rabbits with either medication, 80% of the volume was recovered after 30 min before final closure of the abdominal wall ("drainage"). In the remaining animals the intraabdominal fluid load was not evacuated ("no drainage"). At day 10 after surgery all rabbits were sacrificed for evaluation of adhesion areas by computer-aided planimetry and histopathologic examination. The mean areas of adhesion in both Ringer's lactate groups were significantly larger than in the comparable phospholipid groups (p < .05). In the Ringer's lactate groups, adhesions averaged 341.7 (318.6) mm2 without and 263.3 (275.5) mm2 with drainage. In the phospholipid groups the respective mean areas reached only 24.6 (36.7) mm2 without drainage and 27.0 (49.7) mm2 following evacuation of the fluid 30 min after administration (median, mean in parentheses). These results prove the efficacy of phospholipids after a limited contact period of 30 min. The frequent use of drains in abdominal surgery will not impair the beneficial effect of phospholipids on prevention of adhesions.