Efficacy of a novel polyoxazoline-based hemostatic patch in liver and spleen surgery.

Background: A new hemostatic sealant based on a N-hydroxy-succinimide polyoxazoline (NHS-POx) polymer was evaluated to determine hemostatic efficacy and long-term wound healing and adverse effects in a large animal model of parenchymal organ surgical bleeds.

Methods: Experiment 1 included 20 pigs that were treated with two NHS-POx patch prototypes [a gelatin fibrous carrier (GFC) with NHS-POx and an oxidized regenerated cellulose (ORC) with poly(lactic-co-glycolic acid)-NHS-POx:NU-POx (nucleophilically activated polyoxazoline)], a blank gelatin patch (GFC Blank), TachoSil and Veriset™ to stop moderate liver and spleen punch bleedings. After various survival periods (1-6 weeks), pigs were re-operated to evaluate patch degradation and parenchymal healing.

A novel ex vivo perfusion-based mandibular pig model for dental product testing and training.

Background: A translational ex vivo perfusion-based mandibular pig model was developed as an alternative to animal experiments, for initial assessment of biomaterials in dental and maxillofacial surgery and training. This study aimed to assess the face and content validity of the novel perfusion-based model.

Methods: Cadaveric porcine heads were connected to an organ assist perfusion device for blood circulation and tissue oxygenation.

New polyoxazoline loaded patches for hemostasis in experimental liver resection.

A new cost-effective NHS functionalized polyoxazoline (POx) loaded polymer with strong hemostatic properties has been developed. In this study, we investigate POx loaded hemostatic patches regarding hemostatic efficacy, local inflammatory reaction and wound-healing, as compared to the non-POx treated blanks and commercially available hemostatic products. Hundred and ten rats divided into 11 groups of 10 animals underwent partial liver lobe resection.

The Efficacy of an Ultrapure Alginate Gel in Reducing Adhesion Formation in a Rat Model of Blood Contamination.

Background: Formation of peritoneal adhesions is the most frequent complication of abdominal and pelvic surgery and comprises a lifelong risk of adhesion-related morbidity and mortality. Some of the existing antiadhesive barriers are less effective in the presence of blood. In this study, we investigate the efficacy and safety of ultrapure alginate gel in the presence of blood.

Innate glycosidic activity in metallic implants for localized synthesis of antibacterial drugs.

Iron-containing metallic implants are shown herein to mediate hydrolysis of glycosidic linkages. Using glucuronide prodrugs for broad-spectrum fluoroquinolone antibacterial agents, we capitalize on this behaviour and perform localized synthesis of antimicrobials which affords a significant zone of inhibition of bacterial growth around the metallic material.

Self-expandable tubular collagen implants.

Collagen has been extensively used as a biomaterial, yet for tubular organ repair, synthetic polymers or metals (e.g., stents) are typically used.

Microbial Glucuronidase Inhibition Reduces Severity of Diclofenac-Induced Anastomotic Leak in Rats.

Background: The non-steroidal anti-inflammatory drug diclofenac has been associated with intestinal anastomotic leakage, although the underlying pathophysiology is unclear. Previous data suggest that reactivation of biliary diclofenac metabolites by microbial β-glucuronidases in the gut plays a role in harming the intestinal mucosa, and that microbiome-targeted glucuronidase inhibition prevents this damage. Here, the microbial glucuronidase inhibitor Inh1 was examined for its ability to reduce diclofenac-induced anastomotic leakage in rats.

Safety and Efficacy of Alginate Adhesion Barrier Gel in Compromised Intestinal Anastomosis.

Background: For any anti-adhesive barrier developed for abdominal surgery, the use under conditions in which anastomotic healing is compromised needs to be investigated. The current study evaluates the effect of a new ultrapure alginate gel on early healing of high-risk anastomoses in the ileum and compares this with the gold standard used in clinical practice.

Materials And Methods: In 75 adult male Wistar rats, a 5 mm ileal segment was resected and continuity was restored by construction of an inverted anastomosis.

Repeated remote ischemic preconditioning and isoflurane anesthesia in an experimental model of renal ischemia-reperfusion injury.

Background: In animal studies, remote ischemic preconditioning (RIPC) and anesthetic preconditioning are successful in reducing renal ischemia reperfusion injury (IRI), however the protective effect of RIPC may be improved by repeating the RIPC stimulus.

Methods: Sprague-Dawley rats underwent unilateral nephrectomy followed by 30 min of renal pedicle clamping. Animals were allocated into six groups: sham, control (IRI), RepISO (daily isoflurane anesthesia), RIPC (single dose isoflurane anesthesia and single dose RIPC), RepISO + RIPC (7-day isoflurane anesthesia and single dose RIPC) and RepISO + RepRIPC (7-day isoflurane anesthesia with 7-day RIPC).

Efficacy and Safety of Ultrapure Alginate-Based Anti-Adhesion Gel in Experimental Peritonitis.

Background: Intra-abdominal infection may lead to adhesion and abscess formation. An adhesion barrier can reduce these complications but also aggravate intra-peritoneal infection, causing the opposite effects. The fear of infection propagation has limited clinical adhesion barrier use in a contaminated or infected abdomen.

ARE INTRAVITREAL INJECTIONS WITH ULTRATHIN 33-G NEEDLES LESS PAINFUL THAN THE COMMONLY USED 30-G NEEDLES?

Purpose: This study investigated whether pain from intravitreal injections (IVIs) can be reduced by injecting with a 33-G needle instead of the commonly used 30-G needle. Additionally, several pain-related psychological factors were explored as predictors of outcome.

Methods: This randomized crossover trial included 36 patients who received injections with both needles in randomized order.

Diclofenac causes anastomotic leakage in the proximal colon but not in the distal colon of the rat.

Background: Nonsteroidal anti-inflammatory drugs have been associated with anastomotic leakage. It was studied if diclofenac affects anastomoses differently depending on the location in the gut.

Methods: Ninety-five rats were randomized to 6 groups with an anastomosis in either ileum (IL), proximal colon (PC), or distal colon (DC).

Serosal abrasion of bowel ends does not enhance anastomotic healing.

Background: Anastomotic leakage rates remain unacceptably high, warranting reconsideration of current anastomotic technique. Anastomotic healing may improve by abrading the serosal surface of bowel ends that are invertedly anastomosed, based on the concept that serosal damage evokes inflammatory adherent processes. It is studied if local abrasion leads to stronger anastomoses and reduces leakage.

Ultrapure alginate gel reduces adhesion reformation after adhesiolysis.

Purpose: Adhesiolysis at repeat surgery induces adhesion reformation which seems more virulent than development of de novo adhesions. We studied the effect of a new ultrapure alginate gel on adhesion reformation.

Methods: In 46 male Wistar rats, adhesion formation was induced using the cecal abrasion and peritoneal sidewall excision procedure.

Ultrapure alginate anti-adhesion gel does not impair colon anastomotic strength.

Background: Ultrapure alginate gel is promising in terms of adhesion prevention. Because anti-adhesive barriers have been shown to disturb healing of bowel anastomoses, the effect of ultrapure alginate gel on the repair of colon anastomoses was studied.

Materials And Methods: In 102 male Wistar rats, a 0.

Tacrolimus does not affect early wound healing in a rodent model of bowel anastomoses and abdominal wall closure.

Background: Use of immunosuppressant drugs has been associated with complications in wound healing. The calcineurin inhibitor tacrolimus is thought to have a relatively low complication rate, but preclinical research has yielded contradictory data, prompting the current comprehensive study.

Methods: Three groups of 33 male Wistar rats received a daily subcutaneous dose of 0,5, 2 or 5 mg/kg tacrolimus.

Carprofen for perioperative analgesia causes early anastomotic leakage in the rat ileum.

Background: There is increasing evidence that perioperative use of NSAIDs may compromise the integrity of intestinal anastomoses. This study aims to characterize the negative effects of carprofen on early anastomotic healing in the rat ileum.

Results: In 159 male Wistar rats an anastomosis was constructed in the ileum.

Paracetamol does not compromise early wound repair in the intestine or abdominal wall in the rat.

Background: Paracetamol is a cornerstone for perioperative pain relief. Its mechanism of action may include a local anti-inflammatory effect with inhibition of cyclooxygenase isoenzymes. The scarce literature available on its effects on wound healing consists of preclinical studies into the effect of paracetamol on healing of the musculoskeletal system.

The effect of fibrin glue on the early healing phase of intestinal anastomoses in the rat.

Purpose: Protecting the anastomotic integrity using suture or staple line reinforcement remains an important goal for ongoing research. The present comprehensive study aims to establish the effects of fibrin glue on the early phase of anastomotic healing in the rat intestine.

Methods: One hundred and eight young adult male Wistar rats underwent resection and anastomosis of both the ileum and colon.

Everolimus-induced loss of wound strength can be prevented by a short postoperative delay in its administration.

The use of mammalian target of rapamycin inhibitors coincides with an increased incidence of surgical complications. In previous experiments, serious negative effects of postoperative everolimus on anastomotic strength were found. This study aims to investigate if delayed drug administration can prevent loss of wound strength.

Intraoperative versus early postoperative intraperitoneal chemotherapy after cytoreduction for colorectal peritoneal carcinomatosis: an experimental study.

Background: Perioperative intraperitoneal chemotherapy is used as an adjunct to cytoreductive surgery (CS) for peritoneal carcinomatosis (PC) in order to prolong survival. Worldwide, hyperthermic intraperitoneal chemotherapy (HIPEC), early postoperative intraperitoneal chemotherapy (EPIC), and combinations of the two are used. It remains unclear which regimen is most beneficial.

Hyperthermia and intraperitoneal chemotherapy for the treatment of peritoneal carcinomatosis: an experimental study.

Objective: Hyperthermic intraperitoneal chemotherapy (HIPEC) with mitomycin C can improve survival if used as an adjunct to cytoreductive surgery (CS) for treatment of peritoneal carcinomatosis (PC). It remains unclear if both hyperthermia and chemotherapy are essential for the reported survival benefit.

Methods: Eighty WAG/Rij rats were inoculated intraperitoneally with the rat colon carcinoma cell line CC-531.

Peritoneal cytokines predict mortality after surgical treatment of secondary peritonitis in the rat.

Background: The study aimed to analyze if peritoneal cytokine levels can predict survival in an experimental model for peritonitis. Early identification of patients most at risk for adverse outcomes would facilitate the decision for aggressive therapy in order to maximally exploit their chance for survival.

Study Design: Peritonitis was induced by intraperitoneal injection of a feces/bacteria mixture in 175 rats.

Persistent effects of everolimus on strength of experimental wounds in intestine and fascia.

The introduction of mTOR-inhibitors in transplantation surgery has been associated with an increase in wound complications. We have previously reported a massive negative effect of everolimus on anastomotic strength in rat intestine at 7 days postoperatively. Because it is clinically important to know if this effect persists and occurs generally, repair in both intestine and abdominal wall has been investigated over a period of 4 weeks.

Reduction of oxygenation and blood flow in pedicled bowel segments in the rat and its consequences for anastomotic healing.

Purpose: Experimental studies indicate that perioperative hypoperfusion impairs anastomotic healing. In bowel surgery, the part of bowel that will be anastomosed is often pedicled, leaving the blood supply dependent on the marginal artery only. Little is known about the blood supply in such a segment, and whether anastomotic strength is affected when flow would be reduced.