Evaluation of the Effectiveness of Peritoneal Adhesion Prevention Devices in a Rat Model.

BACKGROUND: Abdominal operations are followed by adhesions, a prevalent cause of abdominal pain, and the most frequent cause for bowel obstruction and secondary female infertility. This rat study addresses adhesion prevention capability of Adept(®), Interceed(®), Seprafilm(®), and a novel device, 4DryField(®) PH which is provided as powder and generates its effect as gel. METHODS: Sixty-eight male Lewis rats had cecal abrasion and creation of an equally sized abdominal wall defect, and were grouped randomly: A control group without treatment (n=10); two groups treated with 4DryField(®) PH using premixed gel (n=15) or in-situ gel technique (n=16); one group each was treated with Seprafilm(®) (n=8), Interceed(®) (n=9), or Adept(®) (n=10). Sacrifice was on day 7 to evaluate incidence, quality, and quantity of adhesions, as expressed via adhesion reduction rate (AR). Histologic specimens were evaluated. Statistical analyses used ANOVA and unpaired t-tests. RESULTS: 4DryField(®) PH significantly reduced incidence and severity of adhesions both as premixed gel (AR: 85.2%) and as in-situ made gel (AR: 100%), a comparison between these two application techniques showed no differences in efficacy. Seprafilm(®) did not reduce incidence but severity of adhesions significantly (AR: 53.5%). With Interceed(®) (AR: 3.7%) and Adept(®) (AR: 16.1%) no significant adhesion-reduction was achieved. Except for inflammatory response with Interceed(®), histopathology showed good tissue compatibility of all other devices. CONCLUSION: 4DryField(®) PH and Seprafilm(®) showed significant adhesion prevention capabilities. 4DryField(®) PH achieved the highest adhesion prevention effectiveness without restrictions concerning mode of application and compatibility and, thus, is a promising strategy to prevent abdominal adhesions.

Impairment of the Peritoneal Surface as a Decisive Factor for Intestinal Adhesions in Intraperitoneal Onlay Mesh Surgery - Introducing a New Rat Model.

BACKGROUND: Meshes implanted intraperitoneally are known to cause adhesions potentially resulting in complications such as chronic pain, enterocutaneous fistula, or mesh infection. This study introduces a model for investigation of intestine-to-mesh adhesions and evaluates as to whether missing of visceral peritoneum is causative. METHODS: In 18 rats, rectangular 1.5 x 2 cm patches of an uncoated polypropylene mesh (Ultrapro(®)) were sewn to the inner abdominal wall next to the cecum. Additionally, a meso-suture ensured contact between cecum and mesh. Rats were assigned to 2 groups: in 8 rats the peritoneum was left intact, in 10 the cecum was depleted from peritoneum with abrasion. Sacrifice was on day 7. Macroscopic evaluation used two adhesion scores. Specimens were evaluated microscopically, statistical analyses employed student's t-test. RESULTS: On day 7, rats with mesh implantation combined with locally de-peritonealization by cecal abrasion mostly showed severe cecum-to-mesh agglutination (mean Lauder score 92%, mean total Hoffmann score 90%), whereas meshes of most animals without cecal abrasion only had some coverage with intraabdominal fat (33%, 24%; p = 0.0002). Histological work-up showed adequate wall ingrowth of mesh in all rats. In animals with cecal abrasion, meshes were mostly adhesive with cecal wall. However, when the peritoneum of cecum was unimpaired, abdominal wall above the mesh as well as cecum usually revealed sub-peritoneal tissue and a mono-layer cell coverage as seen in normal peritoneum. CONCLUSION: This study introduces a model mimicking a clinical situation of e.g. hernia repair by intraperitoneally implanted meshes when mesh has contact with normal and with de-peritonealized intestine. The model might be useful for testing mesh types and coatings as well as other devices for their efficacy in adhesion prevention. The high adhesion scores of rats with local de-peritonealization compared with the low scores of animals with intact peritoneum indicate that the integrity of intestinal peritoneum is a decisive factor for adhesion formation.

[Late stage stenoses of bile ducts after iatrogenic bile duct injuries following cholecystectomy]. / Spätstenosen der Gallengänge im Rahmen von iatrogenen Gallengangsverletzungen nach Cholezystektomie.

INTRODUCTION: Iatrogenic bile duct injuries represent a severe complication after cholecystectomy. For the attending physician therapy and management of these injuries are a challenge. Inadequate and delayed treatment can lead to stenoses at a late stage, which can necessitate further surgical intervention. METHODS: In a study data of 74 patients, who were treated in our clinic for bile duct injuries following cholecystectomy, were analysed retrospectively. RESULTS: A total of 8 patients with late stage bile duct strictures following iatrogenic bile duct injury including the subsequent therapy could be identified. The data of these patients were analysed in respect of cause and strategies to prevent late stage stenoses. In 62 patients the bile duct injury occurred following laparoscopic and in 12 patients following open cholecystectomy. In 16 patients the injury was combined with a vascular lesion. The interval between primary intervention and definitive therapy was 11 days in 53 patients and 1-15 years in 21 patients. In 8 patients the reason for the re-operation after a long interval (1-15 years) was a late stage stenosis. A hepatico-jejunostomy was performed subsequently and during follow-up 5 / 8 patients were symptom-free; 7 patients were re-operated due to a stenosed primary biliodigestive anastomosis and 3 patients each due to atrophy of the right liver lobe and recurrent cholangitis. One patient complained of recurrent cholangitis and a further patient of symptoms due to adhesions. DISCUSSION: If treated inadequately bile duct injuries occurring during cholecystectomy can in the long-term lead to considerable problems such as recurrent cholangitis, late stage stenoses and even to secondary biliary cirrhosis. Therefore, a complex inter-disciplinary therapeutic concept aiming at timely treatment is necessary.

Surgical treatment and outcome of iatrogenic bile duct lesions after cholecystectomy and the impact of different clinical classification systems.

BACKGROUND: Different injury patterns of iatrogenic bile duct lesions after cholecystectomy have prompted the proposal of several different clinical classification systems. The aim of this study was to validate these systems comparatively. METHODS: Results after surgical intervention for iatrogenic bile duct lesions in 74 consecutive patients at a tertiary referral centre were reviewed retrospectively. A new classification (Hannover classification) for iatrogenic bile duct lesions is proposed and compared with four other systems using the present clinical data. RESULTS: Additional vascular lesions were found in 19 per cent. The hospital mortality rate was 3 per cent and the overall hospital complication rate after repair was 26 per cent. Sixteen of 74 patients required early surgical reintervention. The Hannover classification demonstrated a highly significant association between the discrimination of classifiable injury patterns and the different surgical treatments chosen (P < 0.005). The Strasberg and Neuhaus classifications do not consider vascular involvement, whereas the Stewart-Way, Siewert and Neuhaus systems do not discriminate between lesions at or above the bifurcation of the hepatic duct. CONCLUSION: Additional vascular involvement and location of the lesion at or above the bifurcation of the hepatic duct have a major impact on the extent of surgical intervention required and should be reflected in any classification of bile duct injuries.

Major secondary surgery in blunt trauma patients and perioperative cytokine liberation: determination of the clinical relevance of biochemical markers.

BACKGROUND: The aim of this study is to assess the associations between the timing of secondary definitive fracture surgery on inflammatory changes and outcome in the patient with multiple injuries. The study population consists of a series of patients with multiple injuries who were managed using a strategy of primary temporary skeletal stabilization followed by delayed definitive fracture fixation. METHODS: In a prospective cohort study performed at a Level I trauma center, the patients' injuries and operative details as well as immune markers and clinical outcomes were studied. The patients were split into an early secondary surgery group (group ESS, surgery at days 2-4) and a late secondary surgery group (group LSS, surgery at days 5-8). During the posttraumatic course, inflammatory markers (interleukin [IL]-6, tumor necrosis factor-alpha) were determined on a daily basis. Perioperatively, these markers were additionally evaluated at 30 minutes, 7 hours, and 24 hours after initiation of surgery. RESULTS: Secondary surgery on days 2 to 4 was associated with a higher incidence of postoperative organ dysfunction (n = 33 [46.5%]) than secondary surgery on days 5 to 8 (n = 9 [15.7%], p = 0.01). A significant association between the combination of initial IL-6 values > 500 pg/dL plus surgery on days 2 to 4 and the development of multiple organ failure (r = 0.96, p < 0.001) occurred. A correlation between the initial IL-6 values > 500 pg/dL and surgery on days 5 to 8 (r = 0.57, p < 0.07) could not be found. IL-6 also demonstrated a predictive value for the development of multiple organ failure: IL-6 > 500 pg/dL in group ESS, r = 0.96, p < 0.001; IL-6 > 500 pg/dL in group LSS, r = 0.57, p < 0.07. CONCLUSION: According to our data, no distinct clinical advantage in carrying out secondary definitive fracture fixation early could be determined. In contrast, in patients who demonstrated initial IL-6 values above 500 pg/dL, it may be advantageous to delay the interval between primary temporary fracture stabilization and secondary definitive fracture fixation for more than 4 days. In patients with blunt multiple injuries undergoing primary temporary fixation of major fractures, the timing of secondary definitive surgery should be carefully selected, because it may act as a second hit phenomenon and cause a deterioration of the clinical status.

Long term results after multiple injuries including severe head injury.

OBJECTIVE: To describe the long term results in patients with multiple injuries including severe head injury. DESIGN: Retrospective and prospective clinical study. SETTING: Level I trauma centre, Germany. PATIENTS: Patients aged 16-60 years who had been injured more than 2 years before, whose Injury Severity Score was over 20 and whose cranial Abbreviated Injury Score (AIS) was over 3. MAIN OUTCOME MEASURES: Glasgow Outcome Scale (GOS), functional, neuropsychological, vocational and social outcomes. RESULTS: 58 patients, median age 24 (range 16-53, interquartile range (IQR) 21-32) years were investigated 5 (3-9; IQR 4-7) years after their injury. Median ISS was 34 (21-57; IQR 26-41) and GCS 6 (3-8; IQR 4-7). Duration of coma was 10 (2-51; IQR 7-22) days and neurological rehabilitation lasted 169 (10-830; IQR 80-300) days. Movements of the elbow and ankle was most impaired by injury. All psychometric tests showed deficits, particularly in speed of processing, concentration, recent memory, and learning performance. The social environment had been changed in half and vocational rehabilitation was dependent on age. 24 (42%) returned to their former profession, 18 (31%) were retrained to another profession, 16 (27%) were unemployed or retired on a pension. 31 (53%) made a good recovery with moderate disability, 19 (33%) had severe disability, and 8 (14%) remained in a persistent vegetative state assessed by the GOS. CONCLUSION: Early and concentrated rehabilitation facilitates functional, social, and neuropsychological reintegration.