The oral disposition index calculated from a meal tolerance test is a crucial indicator for evaluating differential normalization of postprandial glucose and triglyceride excursions in morbidly obese patients after laparoscopic sleeve gastrectomy.

To determine the normalization of postprandial blood glucose (PG) and triglyceride (TG) excursions in 30 morbidly obese patients with or without diabetes mellitus (DM) 1-year after they underwent a laparoscopic sleeve gastrectomy (LSG) vs. their pre-surgery data, we administered the 75-g oral glucose tolerance test (OGTT) and a meal tolerance test (MTT) using a 75-g glucose-equivalent carbohydrate- and fat-containing meal. The results were as follows; (i) Postoperative body-weight reduction was associated with DM remission and reduced multiple cardiometabolic risks. (ii) OGTT data showing postprandial hyper-insulinemic hypoglycemia in many post-surgery patients were associated with overdiagnosis of improved glucose tolerance. However, postoperative MTT data without hypoglycemia showed no improvement in the glucose tolerance vs. pre-surgery data. (iii) The disposition index (DI) i.e., [Matsuda index] × (Glucose-induced insulin secretion) was progressively worsened from normal glucose tolerance to DM patients after LSG. These post-surgery DI values measured by the MTT were correlated with 2h-plasma glucose levels and were not normalized in DM patients. (iv) The baseline, 2h-TG, and an increase in 2h-TG values above baseline were correlated with the insulin resistance index, DI, or HbA1c; These TG values were normalized post-LSG. In conclusion, the glucose tolerance curve measured by the MTT was not normalized in T2DM patients, which was associated with impaired normalization of the DI values in those patients 1-year after the LSG. However, the baseline TG and a fat-induced 2h-TG values were normalized postoperatively. The MTT can be used to assess normalization in postprandial glucose and TG excursions after LSG.

Effects of a new 75 g glucose- and high fat-containing cookie meal test on postprandial glucose and triglyceride excursions in morbidly obese patients.

A new meal tolerance test (MTT) using a 75 g glucose- and high fat-containing meal was applied to classify glucose intolerance in morbidly obese patients. According to the MTT data, the concordance rate of diagnosis was 82.5% compared to the 75 g oral glucose tolerance test (OGTT) in patients with normal glucose tolerance (NGT, n = 40). In the NGT patients, the insulinogenic index (r = 0.833), Matsuda index (r = 0.752), and disposition index (r = 0.845) calculated from the MTT data were each significantly (p < 0.001) correlated with those derived from the OGTT data. However, in patients with impaired glucose tolerance (IGT, n = 23) or diabetes mellitus (DM, n = 17), the postprandial glucose levels post-MTT were significantly lower than those post-OGTT, without increases in the postprandial insulin levels post-MTT. Thus, the severity of glucose intolerance measured by the MTT was milder than that indicated by the OGTT. Plasma levels of both glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) were increased at the postprandial state, but only the GIP levels post-MTT were significantly higher than those post-OGTT. The enhancement of glucose disposal rates in patients with NGT or IGT after the MTT was associated with increased GIP levels. The postprandial hypertriglyceridemia induced by the MTT was associated with insulin resistance, but it was not associated with the impaired insulinogenic index or the disposition index. These results indicate that the new MTT is clinically useful to evaluate both abnormal glucose and triglyceride excursions caused by abnormal insulin sensitivity and secretions of insulin and gut hormones in morbidly obese patients.

Anti-adhesive effects of a newly developed two-layered gelatin sheet in dogs.

AIM: Adhesion after pelvic surgery causes infertility, ectopic pregnancy, and ileus or abdominal pain. The materials currently available for clinical use are insufficient. The purpose of this study was to develop an anti-adhesive material that overcomes the limitations of conventional anti-adhesive agents. METHODS: The adhesion prevention effects of three methods - a two-layered sheet composed of gelatin film and gelatin sponge, Seprafilm and INTERCEED - were evaluated in 37 dogs. Anti-adhesive effects were investigated macroscopically and microscopically in a cauterized uterus adhesion model. Cell growth on the materials in vitro using human peritoneal mesothelial cells, fibroblasts and uterine smooth muscle cells were also evaluated. RESULTS: The two-layered gelatin sheet had significantly superior anti-adhesive effects compared to the conventional materials (Seprafilm and INTERCEED). A single-cell layer of mature mesothelium formed three weeks after surgery in the gelatin group. Peritoneum regeneration in the Seprafilm and INTERCEED groups was delayed and incomplete in the early phase. Little inflammation around the materials occurred and cell growth was significantly proliferated with the gelatin sheet. CONCLUSION: The anti-adhesive effects of a two-layered gelatin sheet were superior to conventional agents in a cauterized canine uterus model, demonstrating early regeneration of the peritoneum, little inflammation and material endurance. The newly developed two-layered gelatin sheet is a useful option as an anti-adhesive agent for deeply injured and hemorrhagic sites.

Sialic acid level is significantly elevated in IgM enriched protein fraction in sera of cancer patients.

Serum sialic acid (SA) levels are important for diagnosis, follow-up, and mechanistic analysis of malignant diseases. However, little is known about the levels of SA bound to serum IgM. Here, we isolated IgM from sera of healthy individuals and patients with cancer using DEAE chromatography and 8% polyethylene glycol precipitation. In this fraction, which contained partially purified IgM (recovery; 52%; purity: 25%), SA was quantified with fluorescence detection-HPLC (detection limit: 0.08 µM). SA levels in the IgM-enriched fraction was significantly higher in cancer patients (104 ± 27 µM) than in healthy individuals (81 ± 11 µM; P = 0.003).

Development of gelatin flakes, a new type of anti-adhesive material: a preliminary study of in vivo rat adhesion models.

To overcome the problems associated with sheet- or film-type anti-adhesive materials, we developed a new type of anti-adhesive material, gelatin flakes. We made two types of gelatin flakes with or without thermal cross-linking, and preliminarily examined their basic properties and the anti-adhesive efficacy using a rodent adhesion model. Both types of the gelatin flakes rapidly turned into gel and tightly attached the injured surfaces, absorbing the moisture and blood, when applied onto the abraded sites of rats. In addition, these flakes could be sprayed into the desired area by compressed air through a device with a long, thin tube, which could be used in laparoscopic surgery. The anti-adhesive effects of both types of gelatin flakes were similar, and both types were significantly superior compared to the non-treated group. Although further investigations are necessary, the gelatin flakes have unique and useful properties and satisfactory anti-adhesive effects, which indicate that they may be applicable in laparoscopic surgery.

[A new strategy for locally advanced rectal cancer using a nerve-regeneration tube].

In surgery for the treatment of locally advanced rectal cancers affecting the intrapelvic nerves, when an affected nerve is resected in extended surgery to achieve radical cure, the resection results in functional disturbance in the organ it controls. On the other hand, when the nerve remains intact after function-preserving surgery, the risk of local recurrence is high because of possible remnant cancer cells. Thus in performing surgery to treat such cancers, there is a dilemma between the selection of extended surgery or function-preserving surgery. To resolve this, we devised a new strategy in which the cancer is removed radically in extended surgery and organ function is recovered by regeneration of the resected nerve using a nerve-regenerating tube. After animal experiments had confirmed the regeneration of nerve functions with nerve-regenerating tubes, we followed this new strategy to treat 17 patients with locally advanced cancers who underwent extended surgery plus the regeneration of the resected nerve using the nerve-regenerating tube. Nerve function was restored to a significant degree in 16 of the 17 patients.

Regeneration of Functional Bladder Using Cell-seeded Amnion and P(LA/CL) Scaffolds.

Long-term bladder regeneration has not been successful instead of augmentation with gastrointestinal segments, as is commonly performed for bladder reconstruction. To evaluate whether or not cell-seeded bioabsorbable materials regenerate half-resected bladder in a rabbit model. Female Japanese white rabbits were divided two groups: cell-seeded material (CSM) group and Control (n = 6 each). Control rabbits underwent resection of half the bladder. CSM rabbits were sutured with cell-seeded amniotic membrane and P(LA/CL) material after bladder resection. After 6, 12, and 18 months, rabbits underwent X-ray and cystometry, and bladder tissues after 18 months were subjected to functional and histological analyses. X-ray confirmed the peristaltic movements of the reconstructed bladders in the CSM group. On cystometry, the mean maximum bladder volume, maximum bladder pressure, and 25 mL bladder volume compliance in the CSM group were significantly greater than in the Control group at 6, 12, and 18 months. In addition, organ bath studies showed good contraction under electrical stimulation with increasing stimulation frequency in the CSM group, while, the Control group showed weak contraction on both tests in the central marginal zone. Furthermore, the rates of neovascularization, urothelial and smooth muscle formation, and neurofilamentation in the CSM group were significantly greater than in the Control group. Oral mucosal cell-seeded amniotic membrane and stomach smooth muscle cell-seeded P(LA/CL) scaffold with omentum after abdominal implantation regenerated functional bladder with satisfactory epithelium and smooth muscle without scarring more than 1 year. Impact Statement Regeneration of functional bladder without using gastrointestinal segments has been a huge challenge to urological reconstruction. Various materials, such as nonbioabsorbable materials and biomaterials have been attempted to reconstruct bladder in animal models. However, the long-term results more than a year failed due to the low biocompatibility, high risks, and difficulty creating the materials. In this study, we revealed long-term bladder regeneration using cell-seeded amniotic membrane and P(LA/CL) material in a rabbit model. The new method of bladder reconstruction seems able to regenerate functional bladder with satisfactory bladder epithelium and bladder smooth muscle function without scarring for more than 1 year successfully.

Development of a novel antiadhesive material, alginate flakes, ex vivo and in vivo.

PURPOSE: Postoperative intra-abdominal adhesion sometimes causes significant morbidity. The aim of this study was to compare the efficacy of our newly developed antiadhesive material, alginate flakes, to the most commonly used combination of hyaluronic acid and carboxymethyl cellulose film. METHODS: Sodium alginate was formed into a gel, powder, or flakes. In the ex vivo study, these different alginate forms were attached onto pig skin and their antisolubility properties in saline and attachment stability were compared. In the in vivo study, a rat surgical adhesion model was used to study the properties of the alginates, and the rats were euthanized on day 14 after surgery. The efficacy of the antiadhesive materials was evaluated using an adhesion scoring system, and the locations that were treated with the antiadhesives were histologically examined. RESULTS: In the alginate groups, the alginate flakes were superior with respect to the antisolubility and the attachment stability ex vivo as well as with respect to the antiadhesive efficacy in vivo. The adhesion score was almost the same as that observed in the alginate flake and cellulose film groups. CONCLUSIONS: We developed an alginate flake material and demonstrated its antiadhesive effects both ex vivo and in vivo. This is the first reported study using this flake-like material, which has a unique characteristic in that it can be applied by spraying in compressed air. Alginate flakes may therefore be especially useful in the field of laparoscopic surgery.

The performance of heparin modified poly(ε-caprolactone) small diameter tissue engineering vascular graft in canine-A long-term pilot experiment in vivo.

Long-term in vivo observation in large animal model is critical for evaluating the potential of small diameter tissue engineering vascular graft (SDTEVG) in clinical application, but is rarely reported. In this study, a SDTEVG is fabricated by the electrospinning of poly(ε-caprolactone) and subsequent heparin modification. SDTEVG is implanted into canine's abdominal aorta for 511 days in order to investigate its clinical feasibility. An active and robust remodeling process was characterized by a confluent endothelium, macrophage infiltrate, extracellular matrix deposition and remodeling on the explanted graft. The immunohistochemical and immunofluorescence analysis further exhibit the regeneration of endothelium and smooth muscle layer on tunica intima and tunica media, respectively. Thus, long-term follow-up reveals viable neovessel formation beyond graft degradation. Furthermore, the von Kossa staining exhibits no occurrence of calcification. However, although no TEVG failure or rupture happens during the follow-up, the aneurysm is found by both Doppler ultrasonic and gross observation. Consequently, as-prepared TEVG shows promising potential in vascular tissue engineering if it can be appropriately strengthened to prevent the occurrence of aneurysm.

Effects of Fiber Diameter and Spacing Size of an Artificial Scaffold on the In Vivo Cellular Response and Tissue Remodeling.

By mimicking the extracellular matrix, nonwoven fabrics can function as scaffolds for tissue engineering application ideally, and they have been characterized regarding their fiber diameter and fiber spacing (spacing size) in vitro. We chronologically examined the in vivo effects of these fabrics on the cellular response and tissue remodeling. Four types of nonwoven polyglycolic acid fabrics (Fabric-0.7, Fabric-0.9, Fabric-3, and Fabric-16 with fiber diameters of 0.7, 0.9, 3.0, and 16.2 µm and spacing sizes of 2.0, 19.3, 19.0, and 825.4 µm, respectively) were implanted into the rat dorsum and subjected to histologic and immunohistochemical analyses from day 3 to 70. With Fabric-0.7, inflammatory cells (mainly M1 macrophages) and myofibroblasts with collagen type III accumulated mainly on the surface of the fabric and did not infiltrate inside the fabric initially, likely due to the narrow fiber space. Massive formation of collagen type I then appeared with the degradation of the fabrics, and finally, the remodeled tissue turned into a dense scar. With Fabric-0.9 and Fabric-3, inflammatory cells (predominantly M2 macrophages) were seen in all layers of the fabric initially. A mild increase in collagen type I was then seen, with few myofibroblasts, and the remodeled tissue ultimately showed a relatively little scar with an adequate thickness of the tissue induced by the fabrics. With Fabric-16, inflammatory cells (predominantly M1 macrophages) infiltrated into all layers of the fabric initially along with many myofibroblasts, especially in the hole. Lately, massive formation of collagen type I was noted due to the slow degradation of the fabric, with the shrinking of the fabric substantially, and the remodeled tissue finally turned to a dense scar. These findings suggest that optimizing the spacing size as well as the fiber diameter of artificial scaffolds may control the cellular response and tissue remodeling and facilitate favorable tissue regeneration without scar formation.

Indication of peritonectomy for peritoneal dissemination.

A total of 521 patients with peritoneal carcinomatosis (PC) were treated by peritonectomy and perioperative chemotherapy. Each of the 95, 58, 316, 31, 10 and 11 patients were from gastric, colorectal, appendiceal, ovarian, small bowel cancer and mesothelioma, respectively. The distribution and volume of PC are recorded by the Sugarbaker peritoneal carcinomatosis index (PCI). Peritonectomy was performed with a radical resection of the primary tumor and all gross PC with involved organs, peritoneum, or tissue that was deemed technically feasible and safe for the patient. The postoperative major complication of grade 3 was found in 14%, and total 30-day mortality was 2.7%. The survival of gastric cancer patients with a PCI score ≤ 6 was significantly better than those with a PCI score ≥ 7. In appendiceal neoplasm, patients with PCI score less than 28 showed significantly better survival than those with PCI score greater than 29. The survival of colorectal cancer patients with a PCI score ≥ 11 was significantly poorer than those with a PCI score ≤ 10. Among the various prognostic factors in appendiceal neoplasm and gastric cancer patients, CC-0 complete cytoreduction was the most important independent prognostic factor. Peritonectomy is done to remove macroscopic disease and perioperative intraperitoneal chemotherapy to eradicate microscopic residual disease aiming to remove disease completely with a single procedure. Peritonectomy combined with perioperative chemotherapy may achieve long-term survival in a selected group of patients with PC. The higher mortality rate underlines this necessarily strict selection that should be reserved to experienced institutions.

Thoracoscopic radical surgery for a morbidly obese patient with early lung cancer after laparoscopic sleeve gastrectomy: a case report.

BACKGROUND: We experienced a case of early stage lung cancer involving a morbidly obese patient. Obesity is associated with a higher incidence of surgical complications. We examined the effectiveness of laparoscopic sleeve gastrectomy as a primary weight loss procedure in a morbidly obese patient who required oncological surgery. CASE PRESENTATION: A 64-year-old morbidly obese female with a body mass index of 43.5 kg/m2 was referred to our hospital to undergo weight loss. A right-sided lung mass was found incidentally on computed tomography conducted in preparation for laparoscopic sleeve gastrectomy, which was performed prior to tumor surgery. As a result, weight loss was achieved within 2.5 months after the laparoscopic sleeve gastrectomy, and the patient's type-2 diabetes, hypertension, and dyslipidemia, which are linked to obesity, were markedly ameliorated. After a quick intraoperative pathological inspection revealed that the tumor was malignant, thoracoscopic right lung superior lobe resection was performed safely. CONCLUSIONS: Laparoscopic sleeve gastrectomy proved to be a powerful approach in a case in which a morbidly obese patient with early stage cancer needed to lose weight rapidly.

The usefulness of re-attachability of anti-adhesive cross-linked gelatin film and the required physical and biological properties.

BACKGROUND: To overcome the unfavorable issues associated with conventional anti-adhesive HA/CMC film, we developed an anti-adhesive thermally cross-linked gelatin film. OBJECTIVE: We tried to clarify the re-attachability of the film and the required properties concerning the film thickness, stiffness and anti-adhesion effect. METHODS: To determine the optimal thickness, 5 kinds of the thickness of gelatin film and the conventional film were analyzed by the tensile test, shearing test, buckling test and tissue injury test. Finally, using the optimal film thickness, we tried to clarify the anti-adhesion effect of the reattached film. RESULTS: The tensile and shearing test showed gelatin films ≥30 µm thick had greater tensile strength and a smaller number of film fractures, than the conventional film. The buckling and tissue injury test showed gelatin films ≥60 µm thick had higher buckling strength and worse injury scores than the conventional film. The anti-adhesive effect of re-attached gelatin film using optimal thickness (30-40 µm) found the anti-adhesion score was significantly better than that of the control. CONCLUSIONS: Provided it has an optimal thickness, gelatin film can be reattached with enough physical strength not to tear, safety stiffness not to induce tissue injury, and a sufficient anti-adhesion effect.

Laparoscope-assisted superlow anterior resection combined with inter sphincteric rectal dissection for very low advanced rectal cancers combined with preoperative chemotherapy.

Transanal intersphincteric resection (ISR) has been increasingly used as a surgical treatment for extremely low rectal cancer. We hypothesized that high quality less invasive surgery could be achieved if ISR and laparoscopic surgery were combined. The patient was a 46-year-old male with advanced rectal cancer on the lower rectum adjacent to the dentate line. The patient refused abdomino-perineal resection (APR), so we performed laparoscope-assisted ISR after preoperative chemotherapy. Previous dissection of this patient facilitated the muscle layer-oriented curative dissection, and more importantly, made the subsequent laparoscopic rectal excision effortless. This patient showed favorable recovery including postoperative anal function with no complications or recurrent disease. This procedure is feasible and has favorable short-term results for the radical treatment of very low rectal disease, while preserving anal function. This operative procedure may be appropriate for locally advanced rectal cancers to avoid a permanent colostomy.

Regeneration of peritoneum using amniotic membrane to prevent postoperative adhesions.

BACKGROUND/AIMS: Adhesions following intraperitoneal surgery are frequent causes of small bowel obstruction. Attempts to prevent postoperative adhesions have mostly proven disappointing clinically. Currently used by ophthalmologists in ocular surface disorders, amniotic membrane transplantation can reduce inflammation and promote re-epithelization. We used amniotic membrane for facilitating peritoneal regeneration and prevention of adhesions with surgical trauma. METHODOLOGY: 20 rats were randomized in equal number into treatment or control groups. Seven days after operation, the incidence and severity of adhesions were evaluated. Histologic and immunohistochemical analyses were examined at 1, 4, 10 weeks after operation. RESULTS: While severe adhesions were observed after 1 week between the cecum and surrounding organs in the control group, adhesion formation was significantly reduced in the amniotic membrane group. Histologic examination demonstrated that free-floating myofibroblasts in the peritoneal cavity attached to surfaces of amniotic membrane grafts to form a layered structure. Free-floating mesothelial cells were incorporated into the regenerating mesothelium on the myofibroblast layer in 4 weeks, while implanted amniotic membrane grafts were absorbed by 10 weeks. In the amniotic membrane group the cecum appeared nearly normal. CONCLUSIONS: Amniotic membrane grafts reduced intraperitoneal adhesions after surgical trauma, were well absorbed, and served as a substrate for regenerating mesothelium.

Outcomes of total pelvic exenteration for colorectal cancer.

BACKGROUND/AIMS: Pelvic recurrence occurs in 4-33% of patients who have undergone a curative resection of primary rectal cancer and is thus a serious problem. However, the best treatment for primary rectal cancer remains unclear. In the present study was assessed the outcomes of total pelvic exenteration for colorectal cancer retrospectively. METHODOLOGY: In the present study was investigated the medical charts of 25 patients who underwent total pelvic exenteration for primary colorectal cancer (n = 12) or postoperative local recurrence of colorectal cancer (n = 13) at the Department of Surgery (Division of Digestive Surgery) of the Kyoto Prefectural University of Medicine between the years 1997-2005. RESULTS: The mean disease-free time interval between the first operation for primary colorectal cancer and total pelvic exenteration for the recurrence was 919 days (range, 203-3460 days). Total pelvic exenteration required a mean operation time of 940 minutes (range, 540-1395 minutes). The mean carcinoembryonic antigen (CEA) value was 25.5 ng/ml (range, 1-171.8 ng/ml). Five-year survival was achieved in 9 patients (36%) and inhospital death occurred in 3 patients (12%). The patients with curative resection survived significantly longer than the patients with non-curative resection. CONCLUSIONS: When curative resection is achieved, total pelvic exenteration for colorectal cancer can result in long-term survival.

Efficacy of prophylactic extended lymphadenectomy with gastrectomy for patients with node-negative advanced gastric carcinoma.

BACKGROUND/AIMS: Extended lymphadenectomy with gastrectomy is widely performed for patients with advanced gastric carcinoma. However, the therapeutic value of prophylactic extensive lymphadenectomy in patients with node-negative advanced gastric cancer is controversial. METHODOLOGY: We retrospectively analyzed 221 patients who underwent curative gastrectomy for advanced gastric carcinoma without lymph node metastasis to evaluate the effect of prophylactic extended lymphadenectomy on postoperative survival. The postoperative survival rate of patients who underwent extended lymphadenectomy was compared with that of patients who underwent limited lymphadenectomy. Predictive risk factors for tumor recurrence and recurrent patterns also were analyzed. RESULTS: Extended lymphadenectomy improved the postoperative survival rate of patients with advanced tumors even when lymph node spread was absent. Whether or not prophylactic extended lymphadenectomy was performed significantly affected tumor recurrence in patients with node-negative advanced gastric carcinoma. CONCLUSIONS: Extensive lymphadenectomy with gastrectomy prolongs survival of patients with node-negative advanced tumors.

Two-layer sheet of gelatin: A new topical hemostatic agent.

BACKGROUND/OBJECTIVE: Uncontrolled surgical bleeding is associated with increased morbidity, mortality, and hospital cost. Topical hemostatic agents available today have problems controlling hemostatic effects; furthermore, their handling is difficult and they are unsafe. METHODS: We devised a new hemostatic agent comprising gelatin sponge and film designed to be applied to the bleeding site, thereby creating a topical hemostatic agent made of gelatin alone. The gelatin was prepared by alkali treatment to eliminate viral activity. Hemostatic effects, surgical handling, and tissue reactions of the materials, namely a two-layer sheet of gelatin, TachoSil, and gelatin sponge, were evaluated using 21 dogs' spleens. RESULTS: The two-layer gelatin sheet and gelatin sponge exhibited superior hemostatic effects (100% hemostasis completed) compared with TachoSil (0-17% hemostasis). The gelatin matrix immediately absorbed blood flowing from wounds and activated the autologous components in the absorbed blood that promoted coagulation at the bleeding site. The two-layer gelatin sheet had the best surgical handling among the evaluated materials. Materials made of gelatin were associated with fewer inflammatory reactions compared with materials of TachoSil. CONCLUSION: The two-layer sheet of gelatin is a useful topical agent because of its superior hemostatic effects and usability, and is associated with a lower risk of transmitting diseases and inflammatory reactions.

Reduction of Pulmonary Air Leaks with a Combination of Polyglycolic Acid Sheet and Alginate Gel in Rats.

Postoperative air leaks remain a major cause of morbidity after lung resection. This study evaluated the effect of a combination of polyglycolic acid (PGA) sheet and alginate gel on pulmonary air leaks in rats. Four pulmonary sealing materials were evaluated in lung injury: fibrin glue, combination of PGA sheet and fibrin glue, alginate gel, and combination of PGA sheet and alginate gel. With the airway pressure maintained at 20 cmH2O, a 2 mm deep puncture wound was created on the lung surface using a needle. Lowering the airway pressure to 5 cmH2O, each sealing material was applied. The lowest airway pressure that broke the seal was measured. The seal-breaking pressure in each experimental group was fibrin, 10.4 ± 6.8 cmH2O; PGA + fibrin, 13.5 ± 6.5 cmH2O; alginate gel, 10.3 ± 4.9 cmH2O; and PGA + alginate, 35.8 ± 11.9 cmH2O, respectively. The seal-breaking pressure was significantly greater in the PGA + alginate gel group than in the other groups (p < 0.01). There were no significant differences among the other three groups. Alginate gel combined with a PGA sheet is a promising alternative to fibrin glue as a safe and low-cost material for air leak prevention in pulmonary surgery.

New polyglycolic acid fabric for the prevention of postoperative pancreatic fistulas.

BACKGROUND: The incidence of postoperative pancreatic fistula (POPF) after distal pancreatectomy is approximately 30%. The most serious complications of pancreatic resection, such as mortality and prolonged hospitalization, are unresolved despite the proposal of various surgical procedures. We developed a new polyglycolic acid (PGA) fabric composed of fine diameter fibers to prevent POPF, and macroscopically and microscopically evaluated the effects of applying it to the pancreatic remnant. METHODS: The ventral pancreatic surface was cauterized to create the experimental model of POPF in 33 female Wistar/ST rats. The injured sites were wrapped with nonwoven PGA fabrics of different fiber diameters and porosities in the treated rats; one group of rats remained untreated. Survival, incidence of generalized peritonitis, and microscopic findings around the pancreas were investigated. RESULTS: The PGA fabrics acted as a scaffold for tissue repair and resulted in superior survival. Generalized peritonitis was milder in the PGA treated groups. With the new PGA fabric, abundant fibroblast infiltration and a uniformly-developed, self-organized barrier wall prevented both pancreatic leak and spread of inflammation. CONCLUSION: Application of the newly developed PGA fabric to the pancreatic remnant prevented POPF, and the essential factor for preventing pancreatic leak was the early formation of a self-organized barrier.