Prevention of SSI in Cardiac Surgery by Using Intraoperative Measures for High-Risk Patients as Standard Precautions against Mediastinitis / 日本心臓血管外科学会雑誌

Background : Risk factors for surgical site infection (SSI) are thought to include poorly controlled diabetes mellitus, dialysis, and a long operating time, but patients without risk factors can also develop infection. Therefore, it is possible that SSI could be prevented by routinely using the precautions against SSI developed for high-risk patients. We investigated the route and pathogenetic mechanism of mediastinitis, which is the most frequent SSI after cardiac surgery. We hypothesized that mediastinitis occurred when the deep sternal marrow was contaminated by skin bacteria. Based on this hypothesis, we investigated the efficacy of various intraoperative prophylactic methods for preventing mediastinitis. Methods : We evaluated 658 patients undergoing cardiac surgery at our institution between April 2011 and July 2016. They were classified into two groups. Group C comprised 406 patients who received standard insertion of a sternal retractor after sternotomy. Group S was 252 patients in whom a retractor was inserted after covering the sternal marrow with oxidized cellulose hemostats and belt-like thin towels, with surplus parts of the towels being used to fill subcutaneous dead space at the superior and inferior margins of the midline wound. We investigated the following 10 risk factors for mediastinitis: diabetes (HbA1c≥7.5), renal failure (Cr≥2), smoking, obesity (BMI≥30), reoperation, urgent/emergency operation, intubation in the preoperative period, long operating time (≥8 h), reopening the chest for hemostasis, and coronary artery bypass grafting (CABG). Factors associated with mediastinitis were determined using univariate modeling analysis followed by multi-variate logistic regression analysis. Results : Mediastinitis occurred in 13 patients (2.0%). The significant risk factor for mediastinitis were urgent/emergency operation and CABG, but 1 patient had no risk factors. A univariate analysis showed statistical significance in CABG, presence of maneuver covering the sternal marrow, JapanSCORE-II in mortality and deep sternum infection (DSI). Reopening the chest for hemostasis, CABG, aortic aneurysm, plural risk factors, and JapanSCORE-II in DSI were identified as a risk factor by multiple logistic regression, not all factors showed a significant difference. Mediastinitis only occurred in group C, and it was significantly less frequent in group S with additional precautions against infection including propensity score matching analysis (p<0.05). Conclusion : When the bone marrow of the transected sternum was covered tightly to protect it from contamination by skin bacteria during cardiac surgery, the frequency of postoperative mediastinitis was significantly reduced.

Study on Degradation of Oxidized Regenerated Cellulose Absorbable Hemostatic Products / 中国医疗器械杂志

<p><b>OBJECTIVE</b>To study the degradation of oxidized regenerated cellulose absorbable hemostatic products.</p><p><b>METHODS</b>The morphology of the oxidized regenerated cellulose hemostatic products before and after degradation was observed by FTIR and SEM. The degradation products were determined by GPC and HILIC-ELSD.</p><p><b>RESULTS</b>In the initial stage of degradation, there was a great change in morphology. GPC determined its degradation end point was 10 d; it was determined that its degradation products contained glucose (0.13%) and cellobiose (0.17%) and other components.</p><p><b>CONCLUSIONS</b>A method was established for determining the end point of degradation of oxidized regenerated cellulose, which provided a new idea and reference for the study of the degradation end point.</p>

Efficacy of Oxidized Regenerated Cellulose, SurgiGuard®, in Porcine Surgery

PURPOSE: Adequate hemostasis is important for postoperative outcomes of abdominal surgery. This study evaluated the hemostatic effects and accompanying histopathological changes of a novel oxidized regenerated cellulose, SurgiGuard®, during abdominal surgery. MATERIALS AND METHODS: Ten pigs underwent wedge resection of the spleen (1×1 cm) and liver (1.5×1.5 cm). The resected surface was covered with Surgicel® fabric or fibril type (Group A) or SurgiGuard® fabric or fibril type (Group B). Surgicel® and SurgiGuard® were randomized for attachment to the resected surface by fabric type (n=5) or fibril type (n=5). Blood loss was measured 5, 7, and 9 min after resection. Pigs were necropsied 6 weeks postoperatively to evaluate gross and histopathological changes. RESULTS: There was no significant difference in total blood loss between groups [spleen fabric: Group A vs. Group B, 4.38 g (2.74–6.43) vs. 3.41 g (2.46–4.65), p=0.436; spleen fibril: Group A vs. Group B, 3.44 g (2.82–6.07) vs. 3.60 g (2.03–6.09), p=0.971; liver fabric: Group A vs. Group B, 4.51 g (2.67–10.61) vs. 6.93 g (3.09–9.95), p=0.796; liver fibril: Group A vs. Group B, 3.32 g (2.50–8.78) vs. 3.70 g (2.32–5.84), p=0.971]. Histopathological analysis revealed no significant difference in toxicities related to Surgicel® or SurgiGuard® [inflammation, fibrosis, foreign bodies, and hemorrhage (spleen: p=0.333, 0.127, 0.751, and 1.000; liver: p=0.155, 0.751, 1.000, and 1.000, respectively)]. CONCLUSION: SurgiGuard® is as effective and non-toxic as Surgicel® in achieving hemostasis after porcine abdominal surgery.

Efficacy evaluation of SurgiGuard® in partially hepatectomized pigs

BACKGROUNDS/AIMS: This study evaluated the hemostatic effects of a novel oxidized regenerated cellulose, SurgiGuard®, during liver surgery, using a reproducible and clinically relevant animal model. METHODS: Fifteen mini-pigs underwent left partial hepatectomy. They were randomized to treatment of the resected surface with SurgiGuard® (Group C [test], n=5), Surgicel® (Group B [reference], n=5), or nothing (Group A [control], n=5). Blood loss was measured 5, 7 and 9 min after resection. Time to hemostasis was recorded. Mini-pigs were necropsied 4 or 6 weeks postoperatively to evaluate toxicity changes and material dissolution. RESULTS: The median resected liver weight was 2.13 g (2.02-2.20) in control group, 2.04 g (2.01-2.13) in reference group, and 2.01 g (1.99-2.12) in test group (p=0.024). Median total blood loss was 57.18 g (52.02-59.54) in control group, 32.52 g (27.66-35.10) in reference group, and 35.52 g (25.70-38.71) in test group (p=0.008). Blood loss at 0-5 minutes and 7-9 minutes was significantly different between groups (p=0.009 and p=0.006, respectively). At necropsy, no hematomas, granulomas, or adhesions were noted in any group. Histopathological analysis revealed no changes suggesting toxicity related to SurgiGuard®. CONCLUSIONS: SurgiGuard® is as effective as Surgicel® in achieving hemostasis after porcine partial liver resection.

Antiadhesive effect and safety of oxidized regenerated cellulose after thyroidectomy: a prospective, randomized controlled study / 대한외과학회지

PURPOSE: To evaluate the antiadhesive effects and safety of an oxidized regenerated cellulose (Interceed) after thyroidectomy. METHODS: Seventy-six thyroidectomized patients were prospectively randomized into two groups with regard to the use of Interceed. We evaluated each group for their adhesive symptoms using four subjective and four objective items at the 2nd week, 3rd and 6th month after thyroidectomy. All patients were examined for vocal cord motility by indirect laryngoscope at each period. RESULTS: Total adhesion scores at each postoperative follow-up period decreased with time, but were not significantly different in each group. The median score for swallowing discomfort for liquid was significantly lower in the Interceed group than in the control group 2 weeks after surgery. In addition, the severity of skin adhesion to the trachea was reduced in the Interceed group compared with the control group 6 months after surgery. During the study, there were no adverse effects or significant differences in postoperative complications between the groups. CONCLUSION: Interceed appeared to be safe and effective in improving neck discomfort at early postoperative periods and preventing skin adhesion to the trachea 6 months after thyroidectomy.

Assessment of combination techniques in enhancing the regenerative potential of tricalcium phosphate graft in treatment of infrabony periodontal defects.

Aims: The purpose of the present study was to evaluate and compare the clinical outcome of infrabony defects following reconstructive surgery with the use of tricalcium phosphate (TCP) alone; TCP and citric acid (CA) root conditioning; and TCP, CA, and oxidized regenerated cellulose (ORC) membrane. Materials and Methods: Thirty-nine systemically healthy subjects with vertical infrabony defect were initially selected based on intraoral periapical radiographs and clinical examination to record probing pocket depth (PPD) and clinical attachment level (CAL). Only 21 defects revealed two-walled configuration on surgical debridement. These defects were selected and randomly allotted to the study groups. Group 1 defects were treated with TCP, group 2 with TCP+CA, and group 3 with TCP+CA+ORC. PPD, CAL, defect depth (DD), and level of alveolar crest (AC) were evaluated at the time of initial surgery and after 6 months at surgical re-entry. These measurements were utilized to calculate PPD reduction, CAL gain, defect fill (DF), %defect fill (%DF), and crestal resorption (CR). Statistical Analysis: A paired t-test was used for assessing changes in each group. Unpaired t-test was used for intergroup comparisons. Results: All three groups showed statistically significant PPD reduction, CAL gain, DF, and %DF, but insignificant CR at the end of 6 months. On intergroup comparison, no statistically significant differences were noted between the groups for all the parameters. Conclusion: Efficacy of combination techniques using TCP+CA; TCP+CA+ORC in treatment of periodontal infrabony defects is at least equal to that of TCP alone.