O46 SUTURABLE MESH IMPROVES OUTCOMES FOR LAPAROTOMY CLOSURE IN COMPARISON TO POLYPROPYLENE SUTURE IN A REALISTIC PORCINE MODEL

Aim Laparotomy closures fail due to suture pull-through. We hypothesize that a novel suturable mesh device may limit pull-through via mechanisms of force distribution at the suture-tissue interface and fibrous encapsulation of the device filaments. This new tissue approximation device may lead to improved outcomes for laparotomy closure. Material and Methods Fifteen domestic swine 74 kg in size were randomly allocated to three groups for epigastric laparotomy closure with either size 0 suturable mesh, number 1 suturable mesh, or number 1 polypropylene. All three devices were placed in running fashion with 1 cm bites and 1 cm travels. Primary endpoints were hernia formation at 13 weeks and a semiquantitative analysis of the histological tissue response. Secondary endpoints included adhesions, surgical site occurrence (SSO), and documentation of “loose sutures”. Results There were numerically fewer hernias in the number 1 suturable mesh group. Nine of the 10 suturable mesh devices were well encapsulated within the tissues and could not be pulled away, while 4 of the 5 polypropylene sutures were loose. Adhesions were least for number 1 suturable mesh. Histologically, the suturable mesh implanted devices showed good fibrovascular ingrowth and were judged to be “non-irritants”. The soft tissue response was statistically greater (p = .006) for the number 1 suturable mesh than for the number 1 polypropylene. Conclusions The mechanism of how meshes support closure sites is clearly demonstrated with this model. Suturable mesh has the potential to change surgical algorithms for abdominal wall closure.

Full bandwidth electrophysiology of seizures and epileptiform activity enabled by flexible graphene micro-transistor depth neural probes

ABSTRACTMapping the entire frequency bandwidth of neuronal oscillations in the brain is of paramount importance for understanding physiological and pathological states. The ability to record simultaneously infraslow activity (<0.1 Hz) and higher frequencies (0.1-600 Hz) using the same recording electrode would particularly benefit epilepsy research. However, commonly used metal microelectrode technology is not well suited for recording infraslow activity. Here we use flexible graphene depth neural probes (gDNP), consisting of a linear array of graphene microtransistors, to concurrently record infraslow and high frequency neuronal activity in awake rodents. We show that gDNPs can reliably record and map with high spatial resolution seizures, post-ictal spreading depolarisation, and high frequency epileptic activity through cortical laminae to the CA1 layer of the hippocampus in a mouse model of chemically-induced seizures. We demonstrate functionality of chronically implanted devices over 10 weeks by recording with high fidelity spontaneous spike-wave discharges and associated infraslow activity in a rat model of absence epilepsy. Altogether, our work highlights the suitability of this technology for in vivo electrophysiology research, in particular, to examine the contributions of infraslow activity to seizure initiation and termination.

Needle Insertion Difficulty Algorithm (NIDA): A novel pilot study to predict Huber needle insertion difficulty in totally implanted devices

Safeguarding of venous assets in cancer patients provides for positioning vascular devices. In totally implanted central venous access devices, hereinafter referred as TIVADs, it’s necessary introducing Huber needle, into subcutaneous port, to use it. This procedure is not easy for all implanted devices. The procedural difficulty is to be attributed both to the type of the implanted port and to the skill of the clinician. The degree of patient satisfaction is variable and related with the clinician performing the maneuver. It follows a professional dissatisfaction of the clinician and a hesitation of the patient. Moreover, the incorrect positioning of the Huber needle into the port, could lead to the infusion of antiblastic drugs into the subcutaneous tissue with the consequent tissue damage due to extravasation of the drugs. Evaluation of different characteristics of TIVADs, allowed grouping them, in different types, setting up the S.P.I.A. method (Subcutaneous Port Investigator Assessment). Collected data from medical records concerning: primary pathology, port’s permanence and using, Huber needle insertion failed events, if a vascular access expert/specialist clinician has been called, weight gain or loss were recruited. These data made it possible to determine the types of implanted ports that were most difficult to insert the Huber needle, creating the N.I.D.A. (Needle Inserting Difficulty Algorithm) as a prognostic index of Huber needle inserting into the port. In particular, the type of implanted port, that is, if it was a brachial or thoracic implant ( p < 0.001), the SPIA type, if type 1, 2, or 3 ( p < 0.001) and the experience of the clinician ( p < 0.001) were considered as predictors of a successful first attempt and then can perform the NIDA. The relevant aspects in the success of the procedure are therefore the type of port (thoracic or brachial), the SPIA type, and the experience of the clinician in the successful insertion of the Huber needle into the port at the first attempt.

Where the infection is isolated rather than the specific species correlates with adherence strength, whereas biofilm density remains static in clinically isolated Candida and arthroconidial yeasts

To colonize and infect the host, arthroconidial yeasts must avoid being killed by the host’s defenses. The formation of biofilms on implanted devices allows fungi to avoid host responses and to disseminate into the host. To better study the mechanisms of infection by arthroconidial yeasts, adherence and biofilm formation were assayed using patient samples collected over 10 years. In clinical samples, adherence varies within species, but the relative adherence is constant for those samples isolated from the same infection site. Herein we document, for the first time, in-vitro biofilm formation by Trichosporon dohaense, T. ovoides, T. japonicum, T. coremiiforme, Cutaneotrichosporon mucoides, Cutaneotrichosporon cutaneum, Galactomyces candidus, and Magnusiomyces capitatus on clinically relevant catheter material. Analysis of biofilm biomass assays indicated that biofilm mass changes less than 2-fold, regardless of the species. Our results support the hypothesis that most pathogenic fungi can form biofilms, and that biofilm formation is a source of systemic infections.