Maximization of the sealing effect of fibrin glue in aortic surgery

OBJECTIVES

Fibrin glue is used to reinforce anastomosis in aortic surgery. There has not yet been a consensus on how it should be applied optimally. This study aimed to define the optimal condition of applying fibrin glue.

METHODS

In experiment 1, we determined the optimal condition for spraying fibrin glue using an expanded polytetrafluoroethylene graft within a needle hole. The length and area of the fibrin cap within the hole were measured. In experiment 2, methods for applying fibrinogen were assessed by comparing brushing and spraying. In experiment 3, swine aorta segments sutured with a Dacron graft were divided into the following three groups: nothing was applied; fibrinogen was sprayed and rubbed using brush. The aorta was clamped and blood was infused from an occlusion catheter inserted into the graft. The pressure at the first appearance of blood leak was recorded.

RESULTS

In experiment 1, among the four groups divided by the pressure and distance of spraying, the fibrin cap area in the group with 0.075 MPa and 2-cm spray distance was significantly larger than that in the group with 0.15 MPa and 2 cm (P < 0.01). In experiment 2, the fibrin cap area in the brushing group was significantly larger than that in the spraying group (P < 0.05). In experiment 3, the capacity to resist endoluminal pressure was higher in the brushing and combined spraying group compared with that in the sequential combined spraying group (P < 0.01).

CONCLUSIONS

The brush and spray methods showed excellent hemostatic outcomes.

Fibrin Sealant Derived from Human Plasma as a Scaffold for Bone Grafts Associated with Photobiomodulation Therapy

Fibrin sealants derived from human blood can be used in tissue engineering to assist in the repair of bone defects. The objective of this study was to evaluate the support system formed by a xenograft fibrin sealant associated with photobiomodulation therapy of critical defects in rat calvaria. Thirty-six rats were divided into four groups: BC (n = 8), defect filled with blood clot; FSB (n = 10), filled with fibrin sealant and xenograft; BCPBMT (n = 8), blood clot and photobiomodulation; FSBPBMT (n = 10), fibrin sealant, xenograft, and photobiomodulation. The animals were killed after 14 and 42 days. In the histological and microtomographic analysis, new bone formation was observed in all groups, limited to the defect margins, and without complete wound closure. In the FSB group, bone formation increased between periods (4.3 ± 0.46 to 6.01 ± 0.32), yet with lower volume density when compared to the FSBPBMT (5.6 ± 0.45 to 10.64 ± 0.97) group. It was concluded that the support system formed by the xenograft fibrin sealant associated with the photobiomodulation therapy protocol had a positive effect on the bone repair process.

Heterologous fibrin sealant potentiates axonal regeneration after peripheral nerve injury with reduction in the number of suture points

The use of suture associated with heterologous fibrin sealant has been highlighted for reconstruction after peripheral nerve injury, having the advantage of being safe for clinical use. In this study we compared the use of this sealant associated with reduced number of stitches with conventional suture after ischiatic nerve injury. 36 Wistar rats were divided into 4 groups: Control (C), Denervated (D), ischiatic nerve neurotmesis (6 mm gap); Suture (S), epineural anastomosis after 7 days from neurotmesis, Suture + Fibrin Sealant (SFS), anastomosis with only one suture point associated with Fibrin Sealant. Catwalk, electromyography, ischiatic and tibial nerve, soleus muscle morphological and morphometric analyses were performed. The amplitude and latency values of the Suture and Suture + Fibrin Sealant groups were similar and indicative of nerve regeneration.The ischiatic nerve morphometric analysis in the Suture + Fibrin Sealant showed superior values related to axons and nerve fibers area and diameter when compared to Suture group. In the Suture and Suture + Fibrin Sealant groups, there was an increase in muscle weight and in fast fibers frequency, it was a decrease in the percentage of collagen compared to group Denervated and in the neuromuscular junctions, the synaptic boutons were reestablished.The results suggest a protective effect at the lesion site caused by the fibrin sealant use. The stitches reduction minimizes the trauma caused by the needle and it accelerates the surgical practice. So the heterologous fibrin sealant use in nerve reconstruction should be considered.

Transected Tendon Treated with a New Fibrin Sealant Alone or Associated with Adipose-Derived Stem Cells

Tissue engineering and cell-based therapy combine techniques that create biocompatible materials for cell survival, which can improve tendon repair. This study seeks to use a new fibrin sealant (FS) derived from the venom of Crotalus durissus terrificus, a biodegradable three-dimensional scaffolding produced from animal components only, associated with adipose-derived stem cells (ASC) for application in tendons injuries, considered a common and serious orthopedic problem. Lewis rats had tendons distributed in five groups: normal (N), transected (T), transected and FS (FS) or ASC (ASC) or with FS and ASC (FS + ASC). The in vivo imaging showed higher quantification of transplanted PKH26-labeled ASC in tendons of FS + ASC compared to ASC on the 14th day after transection. A small number of Iba1 labeled macrophages carrying PKH26 signal, probably due to phagocytosis of dead ASC, were observed in tendons of transected groups. ASC up-regulated the Tenomodulin gene expression in the transection region when compared to N, T and FS groups and the expression of TIMP-2 and Scleraxis genes in relation to the N group. FS group presented a greater organization of collagen fibers, followed by FS + ASC and ASC in comparison to N. Tendons from ASC group presented higher hydroxyproline concentration in relation to N and the transected tendons of T, FS and FS + ASC had a higher amount of collagen I and tenomodulin in comparison to N group. Although no marked differences were observed in the other biomechanical parameters, T group had higher value of maximum load compared to the groups ASC and FS + ASC. In conclusion, the FS kept constant the number of transplanted ASC in the transected region until the 14th day after injury. Our data suggest this FS to be a good scaffold for treatment during tendon repair because it was the most effective one regarding tendon organization recovering, followed by the FS treatment associated with ASC and finally by the transplanted ASC on the 21st day. Further investigations in long-term time points of the tendon repair are needed to analyze if the higher tissue organization found with the FS scaffold will improve the biomechanics of the tendons.

Fibrin Glue and Internal Limiting Membrane Abrasion for Optic Disc Pit Maculopathy

BACKGROUND AND OBJECTIVE

To describe a novel surgical technique using pars plana vitrectomy (PPV), internal limiting membrane (ILM) abrasion, and intravitreal fibrin glue for the treatment of optic disc pit maculopathy.

PATIENTS AND METHODS

Surgical case series technique with scanning electron microscopy (SEM) of human post-mortem eyes.

RESULTS

Using SEM, the authors demonstrate the persistent adherence of vitreous fragments to the optic disc following induction of posterior vitreous detachment in human postmortem eyes. The authors describe a surgical technique using PPV, Tano Diamond Dusted Membrane Scraper for an ILM abrasion, intravitreal fibrin glue (Tisseel), and gas-air exchange to seal optic disc pits. The authors report successful long-term visual and anatomical outcomes in three patients.

CONCLUSIONS

Intravitreal fibrin glue, when combined with ILM abrasion, may be a viable treatment option for optic disc pit maculopathy with good short- and long-term visual acuity outcomes. SEM shows that ILM abrasion removes vitreous fragments, which are persistently adherent and may lead to failure with other interventional techniques. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e271-e277.].

Comparison of the regenerative effect of adipose-derived stem cells, fibrin glue scaffold, and autologous bone graft in experimental mandibular defect in rabbit

BACKGROUND/AIMS

One of the main concerns for maxillofacial and orthopedic surgeons is finding a method to improve regeneration of large craniofacial bone defects. The aim of this study was to investigate the healing and regenerative effects of fibrin glue associated with adipose-derived stem cells (ADSCs) and fibrin glue scaffold alone with autologous bone grafts in experimental mandibular defects of the rabbit.

METHODS

Bilateral uni-cortical osteotomies were performed in the mandible of 20 male Dutch rabbits. The animals were randomly divided into 2 equal groups. In one group, the defect on the right side was treated by fibrin glue associated with ADSCs and the defect on the other side remained as the control. In another group, the defect on the right side was treated with fibrin glue and on the left side with autologous bone graft. After 28 and 56 days, five rabbits from each group were evaluated by computed tomography (CT) and histopathological examinations.

RESULTS

Coronal CT showed a remarkable reconstruction of cortical bone in the fibrin glue associated with ADSCs group at 28 and 56 days post-surgery. Histopathologically, new cortical bony bridge formation was seen increasingly in the fibrin glue, fibrin glue associated with ADSCs, and autologous bone graft groups after 28 days. Statistical analysis of the thickness of new cortical bone in the treatment versus control groups showed a significant difference between fibrin glue alone and fibrin glue associated with ADSCs groups (P = 0.02). No significant difference was found between the fibrin glue associated with ADSCs and the autologous bone graft groups (P > 0.05).

CONCLUSIONS

The healing process had a significant increase in the thickness of new cortical bone when fibrin glue scaffold associated with ADSCs was used.

Fibrin Glue-aided, Instant Epicardial Placement Enhances the Efficacy of Mesenchymal Stromal Cell-Based Therapy for Heart Failure

Transplantation of mesenchymal stromal cells (MSCs) is a promising new therapy for heart failure. However, the current cell delivery routes result in poor donor cell engraftment. We therefore explored the role of fibrin glue (FG)-aided, instant epicardial placement to enhance the efficacy of MSC-based therapy in a rat ischemic cardiomyopathy model. We identified a feasible and reproducible method to instantly produce a FG-MSC complex directly on the heart surface. This complex exhibited prompt, firm adhesion to the heart, markedly improving initial retention of donor MSCs compared to intramyocardial injection. In addition, maintenance of retained MSCs was enhanced using this method, together contributing the increased donor cell presence. Such increased donor cell quantity using the FG-aided technique led to further improved cardiac function in association with augmented histological myocardial repair, which correlated with upregulation of tissue repair-related genes. We identified that the epicardial layer was eliminated shortly after FG-aided epicardial placement of MSCs, facilitating permeation of the donor MSC's secretome into the myocardium enabling myocardial repair. These data indicate that FG-aided, on-site, instant epicardial placement enhances MSC engraftment, promoting the efficacy of MSC-based therapy for heart failure. Further development of this accessible, advanced MSC-therapy is justified.

Fibrin glue for wound repair: facts and fancy

In wound repair, fibrin has a multiplicity of activities, some of which are intrinsic to the protein itself and some attributable to other blood constituents associated with the fibrin clot. Fibrin sealants, which have been approved for hemostasis in the US and Europe, are occasionally used wounds to promote healing. However, inconsistency exists in the literature regarding the benefit of these preparations in the healing process. Morecrude fibrinogen preparations, such as cryoprecipitates made from the patient’s own blood on location, appear from the literature to have better utility in wounds than more purified fibrinogen preparations available through commercial sources. These divergent outcomes are likely attributable to additional blood-derived products being associated with cryo-precipitates compared to the relatively purified commercial fibrinogen preparations. Clearly standard preparations and methods of application of fibrin sealant need to be defined for each particular surgical setting to resolve the many ostensible discrepancies in the current literature. A corollary is that different fibrin sealant preparations are likely to be preferable for different clinical situations.

Fixation of Hydrogel Constructs for Cartilage Repair in the Equine Model: A Challenging Issue

OBJECTIVE

To report on the experiences with the use of commercial and autologous fibrin glue (AFG) and of an alternative method based on a 3D-printed polycaprolactone (PCL) anchor for the fixation of hydrogel-based scaffolds in an equine model for cartilage repair.

METHODS

In a first study, three different hydrogel-based materials were orthotopically implanted in nine horses for 1-4 weeks in 6 mm diameter full-thickness cartilage defects in the medial femoral trochlear ridge and fixated with commercially available fibrin glue (CFG). One defect was filled with CFG only as a control. In a second study, CFG and AFG were compared in an ectopic equine model. The third study compared the efficacy of AFG and a 3D-printed PCL-based osteal anchor for fixation of PCL-reinforced hydrogels in three horses for 2 weeks, with a 4-week follow-up to evaluate integration of bone with the PCL anchor. Short-term scaffold integration and cell infiltration were evaluated by microcomputed tomography and histology as outcome parameters.

RESULTS

The first study showed signs of subchondral bone resorption in all defects, including the controls filled with CFG only, with significant infiltration of neutrophils. Ectopically, CFG induced clear inflammation with strong neutrophil accumulation; AFG was less reactive, showing fibroblast infiltration only. In the third study the fixation potential for PCL-reinforced hydrogels of AFG was inferior to the PCL anchor. PCL reinforcement had disappeared from two defects and showed signs of dislodging in the remaining four. All six constructs fixated with the PCL anchor were still in place after 2 weeks. At 4 weeks, the PCL anchor showed good integration and signs of new bone formation.

CONCLUSIONS

The use of AFG should be preferred to xenogeneic products in the horse, but AFG is subject to individual variations and laborious to make. The PCL anchor provides the best fixation; however, this technique involves the whole osteochondral unit, which entails a different conceptual approach to cartilage repair.

Comparison of the wound healing efficacy of polyglycolic acid sheets with fibrin glue and gelatin sponge dressings in a rat cranial periosteal defect model

Oral surgical procedures occasionally require removal of the periosteum due to lesions, and these raw bone surfaces are prone not only to infection but also to scar formation during secondary healing. The objective of this study was to identify successful methods for reconstruction using periosteal defect dressings. We created 1-cm2 defects in the skin and cranial periosteum of 10-week-old male Wistar rats under isoflurane anesthesia. The animals were assigned to three defect treatment groups: (1) polyglycolic acid sheets with fibrin glue dressing (PGA-FG), (2) Spongel® gelatin sponge dressing (GS), and (3) open wound (control). Postoperative wound healing was histologically evaluated at 2, 4, and 6 weeks. The moist conditions maintained by the GS and PGA-FG treatments protected the bone surface from the destructive effects of drying and infection. Complete wound healing was observed in the GS group but not for all animals in the PGA-FG and control groups. Histologically, osteoblast proliferation on bone surfaces and complete epithelialization with adnexa were observed in the GS group at 6 weeks after surgery. In contrast, PGA sheets that had not been absorbed inhibited osteoblast proliferation and delayed wound healing in the PGA-FG group. Wound surface dressings maintain a moist environment that promotes wound healing, but PGA materials may not be suitable for cases involving exposed periosteum or bone surfaces due to the observed scar formation and foreign-body reaction.

Autologous Fibrin-Base Scaffold for Chondrocytes and Bone Marrow Mesenchymal Stem Cells Implantation: The Development and Comparison to Conventional Fibrin Glue

OBJECTIVE

The authors developed the autologous fibrin-base scaffold for chondrocytes and bone marrow mesenchymal stem cells (BM-MSCs) implantation and evaluated cells viability in autologous fibrin-base scaffold comparing to commercial fibrin glue.

MATERIAL AND METHOD

The chondrocytes and BM-MSCs were seeded into autologous fibrin-base scaffold and commercial fibrin glue. The cell viability and proliferation were evaluated at 1 and 7 days. The histology were evaluated with hematoxylineosin (H&E) staining and cartilaginous matrices formation with Alcian blue, Saffanin-0, Toluidine blue, and Collagen type II staining at 6 weeks. The fixation of the scaffolds was observed.

RESULTS

The chondrocytes and BM-MSCs could not survive in commercial fibrin glue. The chondrocytes and BM-MSCs in autologous fibrin-base scaffold could proliferate and synthesize the cartilaginous matrices on Alcian blue, Saffanin-0, Toluidine blue, and Collagen type II staining at 6 weeks. The fixation strength is excellent.

CONCLUSION

The developed autologous fibrin-base scaffold can be used as the scaffold for chondrocytes and BM-MSCs implantation with potential to implant chondrocytes and BM-MSCs arthroscopically.

A Pilot Study of the Effects of Vivostat Patient-derived Fibrin Sealant in Reducing Blood Loss in Primary Hip Arthroplasty

A pilot study evaluated the effectiveness of Vivostat patient-derived fibrin sealant in reducing blood loss in patients who underwent primary hip arthroplasty. Eighty adult patients undergoing elective surgery were randomized to receive either Vivostat sealant or control (no additional hemostatic treatment). Patients allocated Vivostat sealant donated 120 mL of blood, which was then processed perioperatively to produce a fibrin sealant that was applied to the bleeding wound surfaces just before closure. Transfusion requirements, blood loss during surgery, drain volumes, and daily hematocrit and hemoglobin levels were measured. Hospitalization times, adverse events, and postoperative wound complications were also monitored. Blood loss during surgery and wound drainage volume was lower in the Vivostat group than in the control group, although the differences were not significantly different. Transfusion requirements (median, 270 mL of packed red blood cells) and hospitalization times (both median 7 days) were the same for both groups. No adverse events related to the use of Vivostat occurred. There were indications of a possible reduction in the incidence of postoperative wound oozing (15% vs 25%) and hematomas (6% vs 11%) with the use of Vivostat compared with the control group, although differences were not statistically significant. In conclusion, in this pilot study, use of Vivostat patient-derived fibrin in hip arthroplasty was not associated with a significant reduction in blood loss. Further studies, with larger numbers of patients, may be warranted to investigate a possible benefit of Vivostat in reducing postoperative wound complications.

A Biological Tissue Adhesive and Dissolvent System for Intraocular Tumor Plaque Brachytherapy

PURPOSE

To examine a novel technique for simplified placement and removal of plaque brachytherapy by fibrin glue and urokinase (medac Gmbh, Hamburg, Germany).

MATERIALS AND METHODS

In six enucleated porcine eyes, plaques were placed on the episclera and fibrin glue was applied to cover it. Urokinase was used to dissolve the glue in three eyes and saline was used in three eyes. Adhesion strength was measured further on 15 plaques affixed to porcine eyes (glued in five with intact conjunctiva, glued in five with removed conjunctiva, and sutured in five).

RESULTS

Saline had no effect on the glue-plaque-eye complex, whereas the urokinase (0.38 mL ± 0.08 mL) easily dissolved the adhesion between the glue layer and surrounding tissues. The weight required to detach the plaques was 0.349 kg ± 0.173 kg for glued eyes with intact conjunctiva, 0.405 kg ± 0.083 kg for sutured eyes (P = .59), and 0.032 kg ± 0.004 kg for glued eyes without intact conjunctiva (P ≤ .015).

CONCLUSIONS

The usage of the biological adhesive and dissolvent system was applicable for plaque surgery in an ex vivo animal model.

Can tissue adhesives and platelet-rich plasma prevent pharyngocutaneous fistula formation?

OBJECTIVE

One of the frequently encountered disorders of wound healing following laryngectomy is pharyngocutaneous fistula. However, although studies have been performed with the aim of prevention of pharyngocutaneous fistulae, there are very few studies with tissue adhesives and platelet-rich plasma. In this study, our aim was to investigate the histopathologic changes in wound healing caused by various tissue adhesives and platelet-rich plasma, together with their effects on prevention of pharyngocutaneous fistula.

METHODS

40 male rats were randomly divided into five groups: control, platelet-rich plasma, fibrin tissue adhesive, protein-based albumin glutaraldehyde and synthetic tissue adhesive groups. The pharyngotomy procedure was performed and was sutured. Except the control group, tissue adhesives and platelet-rich plasma were applied. Then, the skin was sutured. On the seventh day, the rats were sacrificed. The skin was opened and pharyngotomy site was assessed in terms of fistulae. The pharyngeal suture line was evaluated histopathologically by using Ehrlich Hunt scale.

RESULTS

Inflammatory infiltration was found to be higher in "platelet-rich plasma" group than "fibrin tissue adhesive" and "synthetic tissue adhesive" groups. The fibroblastic activity of "platelet-rich plasma", "fibrin tissue adhesive" and "protein-based albumin glutaraldehyde" groups was higher than the control group. The positive changes created by platelet-rich plasma and fibrin tissue adhesive at the histopathologic level were found together with no detected fistula. Among the study groups, there was no statistical difference for pharyngeal fistula development. This result may be obtained by the small number of animal experiments.

CONCLUSION

These results shed light on the suggestion that platelet-rich plasma and fibrin tissue adhesive can be used in clinical studies to prevent pharyngocutaneous fistula.

The Effect of Bone Marrow-Derived Mesenchymal Stem Cells and Their Conditioned Media Topically Delivered in Fibrin Glue on Chronic Wound Healing in Rats

Bone marrow-derived mesenchymal stem cells (BM-MSCs) represent a modern approach for management of chronic skin injuries. In this work, we describe BM-MSCs application versus their conditioned media (CM) when delivered topically admixed with fibrin glue to enhance the healing of chronic excisional wounds in rats. Fifty-two adult male rats were classified into four groups after induction of large-sized full-thickness skin wound: control group (CG), fibrin only group (FG), fibrin + MSCs group (FG + SCs), and fibrin + CM group (FG + CM). Healing wounds were evaluated functionally and microscopically. Eight days after injury, number of CD68+ macrophages infiltrating granulation tissue was considerably higher in the latter two groups. Although--later--none of the groups depicted a substantially different healing rate, the quality of regenerated skin was significantly boosted by the application of either BM-MSCs or their CM both (1) structurally as demonstrated by the obviously increased mean area percent of collagen fibers in Masson's trichrome-stained skin biopsies and (2) functionally as supported by the interestingly improved epidermal barrier as well as dermal tensile strength. Thus, we conclude that topically applied BM-MSCs and their CM-via fibrin vehicle--could effectively improve the quality of healed skin in chronic excisional wounds in rats, albeit without true acceleration of wound closure.

[Effects of different fibrin glue combination modes on the proliferation and viability of dental follicle cells]

OBJECTIVE

This study explores the effects of different fibrin glue combination modes on the survival, proliferation, and apoptosis of dental follicle cells (DFCs), as well as to evaluate the feasibility and effectiveness of fibrin glue as transplantation material.

METHODS

The membranes of surviving DFCs were marked using 3,3'-dioctadecyloxa carbocyanine perchlorate (DIO), and the cell number was counted by using ImageJ2x software. The apoptotic cells were marked with prodium iodide (PI).

RESULTS

Compared with that of the 3D-2 and 2D-1 groups, the degradation speed of the 3D-1 group was the slowest. DFCs could survive and grow well in fibrinogen with a concentration of 15 mg · mL⁻¹ supplemented with thrombin with a concentration of 2 U · mL⁻¹. In particular, the 3D-1 combination mode was significantly conducive to cell proliferation and stretching.

CONCLUSION

Fibrin glue can be used as an effective cell transplantation material. The different combination modes have certain effects on cell proliferation. The 3D-1 combination mode is more conducive to the survival and proliferation of DFCs than other modes.

S53P4 bioactive glass and fibrin glue for the treatment of osteochondral lesions of the knee - a preliminary in vivo study in rabbits

The role of the subchondral bone and the importance of treating both bone and cartilage in cases of chondral and osteochondral lesions of the knee have been highly emphasized. There are no current studies on the experimental use of bioactive glass S53P4 (BonAlive®) as granules in the treatment of osteochondral lesions of the knee. Our preliminary study was designed to establish an experimental model and assesses the effect of glass granules fixed with fibrin compared to fibrin alone as fillers of the osteochondral defects created in the weight-bearing and partial weight-bearing regions of the distal femur in six adult rabbits. We found that the size of the distal femur in adult domestic rabbits allows the creation of 4 mm diameter and 5 mm deep osteochondral defects on both the medial femoral condyle and the trochlea, bilaterally, without significantly affecting the activity level of the animals. Retention of the glass granules in the defects was achieved successfully using a commercially available fibrin sealant. At five weeks post-implantation, we found macroscopic and microscopic differences between the four types of defects. The use of bioactive glass S53P4 for filling condylar osteochondral defects in rabbit femora led to the initiation of an early bone repair process, observed at five weeks after implantation, while the filling of trochlear defects with fibrin glue resulted in the appearance of cartilaginous tissue characteristic of endochondral ossification.

Thrombin injection for sealing epicardial collateral perforation during chronic total occlusion percutaneous coronary interventions

Epicardial collateral perforation is a serious complication of retrograde chronic total occlusion percutaneous coronary intervention. We describe two cases of epicardial collateral perforation that were successfully sealed with local thrombin injection.

Comparison of a collagen membrane versus a fibrin sealant after a peroneal nerve section and repair: a functional and histological study

BACKGROUND

To date, fibrin sealant is considered to be one of the most effective substitutes to prevent post-operative fibrosis and to limit neuroma formation after nerve suture. Because fibrin sealant presents a number of drawbacks, more suitable techniques should be considered. The aim of this study was to functionally and histologically compare the efficiency of a fibrin sealant to a resorbable semi-permeable porcine type I collagen membrane after a peroneal nerve lesion and repair on rats.

METHODS

Rats were divided into four groups: (1) a SHAM group (n = 10) in which surgery was performed without damaging the nerve, (2) a LESION group (n = 15) in which the nerve was cut and immediately sutured without additional treatment, (3) a MEMBRANE group (n = 30) in which a collagen membrane was wrapped around the lesion site, and (4) a GLUE group (n = 30) in which the peroneal nerve was coated by fibrin sealant. Peroneal Functional Index (PFI), kinematic analysis of locomotion, muscular atrophy, axonal regrowth, and irritant ranking score (IRS) were performed during three months post-surgery.

RESULTS

Our results indicate that at the third month post-surgery, no difference in both the functional recovery and the histological measurement was observed between groups. However, no deleterious effect was observed following the use of the collagen membrane. Indeed, the porcine membrane was well-integrated into the host tissue, with no noticeable foreign body reaction at three months post-surgery.

CONCLUSION

Our preliminary results highlight the fact that the collagen membrane could be used as an alternative to fibrin sealant in peripheral nerve repair surgery. Indeed, animals in which the collagen membrane was used to wrap the lesion site exhibited similar functional and histological results as animals in which a fibrin sealant was used to coat the lesion. The greatest advantage of this membrane is that it could be used as a drug delivery device, regulated by its degradation rate.

Tolerance and osteointegration of TricOs(TM)/MBCP(®) in association with fibrin sealant in mastoid obliteration after canal wall-down technique for cholesteatoma

CONCLUSION

The TricOs™/MBCP(®) and fibrin sealant composite was a convenient, effective, and well-tolerated material for mastoid cavity filling and immediate reconstruction of the external auditory meatus after cholesteatoma surgery with canal wall down (CWD).

OBJECTIVE

To assess the tolerance and osteointegration of a bone graft substitute, TricOs™/MBCP(®), in association with fibrin sealant for filling the mastoid cavity after cholesteatoma surgery using the CWD technique.

METHODS

In this prospective observational study 57 patients with cholesteatoma suitable for CWD were recruited from April 2006 to April 2008 and followed up for 1 year. The mastoid cavity was filled with TricOs™/MBCP(®) followed by immediate reconstruction of the external auditory meatus covered with fascia temporalis and/or cartilage. The main outcome was skin tolerance assessed by a novel weighted score emphasizing long-term results. The typical weighted reference score was 1.67; skin tolerance was considered acceptable if 75% of patients had a score ≤ 1.67. Secondary outcomes were otorrhea and/or otalgia, hearing, and osteointegration assessed through computed tomography scanning at 12 months.

RESULTS

Forty-one patients had a complete follow-up; 34 (82.3%) patients achieved the main end point with scores ≤ 1.67. Otorrhea decreased postoperatively. No otalgia interfering with daily tasks was reported. Ossicular reconstruction was carried out in 29 patients. Absence of cochlear toxicity was confirmed by unimpaired bone conduction. Preoperative and postoperative speech audiometry results were similar. No serious adverse events were observed. Osteointegration was satisfactory with hyperdensity or intermediate density in 95% of patients at 12 months.

Adherence compounds in embryo transfer media for assisted reproductive technologies

BACKGROUND

This is an update of a Cochrane review first published in The Cochrane Library (2010, Issue 7).To increase the success rate of assisted reproductive technologies (ART), adherence compounds such as hyaluronic acid (HA) and fibrin sealant have been introduced into subfertility management. Adherence compounds are added to the embryo transfer medium to increase the likelihood of embryo implantation, with the potential for higher clinical pregnancy and live birth rates.

OBJECTIVES

To determine whether embryo transfer media containing adherence compounds improved live birth and pregnancy rates in ART cycles.

SEARCH METHODS

The Menstrual Disorders and Subfertility Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) and MEDLINE, EMBASE and PsycINFO electronic databases were searched (up to 13 November 2013) to look for publications that described randomised controlled trials on the addition of adherence compounds to embryo transfer media. Furthermore, reference lists of all obtained studies were checked, and conference abstracts were handsearched.

SELECTION CRITERIA

Only truly randomised controlled trials comparing embryo transfer media containing functional (e.g. 0.5 mg/ml HA) concentrations of adherence compounds versus transfer media containing low or no concentrations of adherence compounds were included. The adherence compounds that were identified for evaluation were HA and fibrin sealant.

DATA COLLECTION AND ANALYSIS

Two review authors selected trials for inclusion according to the above criteria, after which two review authors independently extracted the data for subsequent analysis. Statistical analysis was performed in accordance with the guidelines developed by The Cochrane Collaboration.

MAIN RESULTS

Seventeen studies with a total of 3898 participants were analysed. One studied fibrin sealant, and the other 16 studied HA. No evidence was found of a treatment effect of fibrin sealant as an adherence compound. For HA, evidence of a positive treatment effect was identified in the six trials that reported live birth rates (odds ratio (OR) 1.41, 95% confidence interval (CI) 1.17 to 1.69; six RCTs, N = 1950, I(2) = 0%, moderate-quality evidence). Furthermore, the 14 trials reporting clinical pregnancy rates showed evidence of treatment benefit when embryos were transferred in media containing functional concentrations of HA (OR 1.39, 95% CI 1.21 to 1.60; 14 RCTs, N = 3452, I(2) = 46%, moderate-quality evidence) as compared with low or no use of HA. The multiple pregnancy rate (OR 1.86, 95% CI 1.49 to 2.31; five RCTs, N = 1951, I(2) = 0%, moderate-quality evidence) was significantly increased in the high HA group, but no significant differences in adverse event rates were found (OR 0.74, 95% CI 0.49 to 1.12; four RCTs, N = 1525, I(2) = 0%, moderate-quality evidence).

AUTHORS' CONCLUSIONS

Evidence suggests improved clinical pregnancy and live birth rates with the use of functional concentrations of HA as an adherence compound in ART cycles. However, the evidence obtained is of moderate quality. The increase in multiple pregnancy rate may be the result of use of a combination of an adherence compound and a policy of transferring more than one embryo. Further studies of adherence compounds with single embryo transfer need to be undertaken.

Motor recovery and synaptic preservation after ventral root avulsion and repair with a fibrin sealant derived from snake venom

BACKGROUND

Ventral root avulsion is an experimental model of proximal axonal injury at the central/peripheral nervous system interface that results in paralysis and poor clinical outcome after restorative surgery. Root reimplantation may decrease neuronal degeneration in such cases. We describe the use of a snake venom-derived fibrin sealant during surgical reconnection of avulsed roots at the spinal cord surface. The present work investigates the effects of this fibrin sealant on functional recovery, neuronal survival, synaptic plasticity, and glial reaction in the spinal motoneuron microenvironment after ventral root reimplantation.

METHODOLOGY/PRINCIPAL FINDINGS

Female Lewis rats (7 weeks old) were subjected to VRA and root replantation. The animals were divided into two groups: 1) avulsion only and 2) replanted roots with fibrin sealant derived from snake venom. Post-surgical motor performance was evaluated using the CatWalk system twice a week for 12 weeks. The rats were sacrificed 12 weeks after surgery, and their lumbar intumescences were processed for motoneuron counting and immunohistochemistry (GFAP, Iba-1 and synaptophysin antisera). Array based qRT-PCR was used to evaluate gene regulation of several neurotrophic factors and receptors as well as inflammatory related molecules. The results indicated that the root reimplantation with fibrin sealant enhanced motor recovery, preserved the synaptic covering of the motoneurons and improved neuronal survival. The replanted group did not show significant changes in microglial response compared to VRA-only. However, the astroglial reaction was significantly reduced in this group.

CONCLUSIONS/SIGNIFICANCE

In conclusion, the present data suggest that the repair of avulsed roots with snake venom fibrin glue at the exact point of detachment results in neuroprotection and preservation of the synaptic network at the microenvironment of the lesioned motoneurons. Also such procedure reduced the astroglial reaction and increased mRNA levels to neurotrophins and anti-inflammatory cytokines that may in turn, contribute to improving recovery of motor function.

Hemostats, sealants, and adhesives: a practical guide for the surgeon

Hemostats, sealants, and adhesives are useful adjuncts to modern surgical procedures. To maximize their benefit, a surgeon needs to understand the safety, efficacy, usability, and cost of these agents. To be truly added to a surgeon's own toolbox, the operator must also have knowledge of when and how to best use these materials. This commentary is designed to succinctly facilitate this understanding and knowledge. A nomenclature and classification system based on group, category, and class has been created to help with this process and is provided here. By using this system, materials consisting of similar design and for common indications can be compared. For example, in this system, the three functional groups are hemostats, sealants, and adhesives. The hemostats may be divided into four categories: mechanical, active, flowable, and fibrin sealant. These hemostat categories are further subdivided into generic classes based on the composition of the approved materials. Similarly, categories and classes are provided for sealants and adhesives. In this commentary, the salient points with respect to the characteristics of these agents are presented. A discussion of when these agents can be used in specific indications and how they may be applied to achieve the best results is also provided.

Effect of fibrin glue on the biomechanical properties of human Descemet's membrane

Background

Corneal transplantation has rapidly evolved from full-thickness penetrating keratoplasty (PK) to selective tissue corneal transplantation, where only the diseased portions of the patient's corneal tissue are replaced with healthy donor tissue. Descemet's membrane endothelial keratoplasty (DMEK) performed in patients with corneal endothelial dysfunction is one such example where only a single layer of endothelial cells with its basement membrane (10–15 µm in thickness), Descemet's membrane (DM) is replaced. It is challenging to replace this membrane due to its intrinsic property to roll in an aqueous environment. The main objective of this study was to determine the effects of fibrin glue (FG) on the biomechanical properties of DM using atomic force microscopy (AFM) and relates these properties to membrane folding propensity.

Methodology/Principal Findings

Fibrin glue was sprayed using the EasySpray applicator system, and the biomechanical properties of human DM were determined by AFM. We studied the changes in the “rolling up” tendency of DM by examining the changes in the elasticity and flexural rigidity after the application of FG. Surface topography was assessed using scanning electron microscopy (SEM) and AFM imaging. Treatment with FG not only stabilized and stiffened DM but also led to a significant increase in hysteresis of the glue-treated membrane. In addition, flexural or bending rigidity values also increased in FG-treated membranes.

Conclusions/Significance

Our results suggest that fibrin glue provides rigidity to the DM/endothelial cell complex that may aid in subsequent manipulation by maintaining tissue integrity.

The use of autologous platelet and plasma products in salvage neck dissections: a prospective clinical study evaluating early and late wound healing

OBJECTIVES

To evaluate the effect of autologous platelet and plasma adhesives (APA) on postoperative drainage and soft-tissue fibrosis following neck dissections.

DESIGN

This was a blinded comparative prospective cohort study done as two parts: part one evaluated early post-surgical outcomes and part two evaluated late tissue fibrosis.

METHOD

Salvage neck dissections were stratified into two groups based on severity of prior treatment. High risk patients were defined as those who had previously undergone chemoradiation therapy and autologous platelet adhesives were administered to the surgical wound intraoperatively. The low risk group consisted of patients undergoing salvage neck dissections following radiation only and acted as controls. Part one evaluated postsurgical wound drainage as the primary outcome as well as length of hospital stay and complications. Part two evaluated late postoperative tissue fibrosis by comparing neck skin using the Cutometer. R2 and F0 were the specific Cutometer parameters for quantifying the viscoelastic properties of the skin.

RESULTS

Postoperative wound drainage was significantly less (253.7 vs. 345.8) in the autologous platelet adhesive group as compared to the control group (p less than 0.03). Length of stay in the APA group versus the control group was 3.13 and 3.86 days respectively (p less than 0.004). Both R2 and F0 measurements showed improved viscoelastic properties of the skin in the APA group (R2 p less than 0.05, F0 p less than 0.05).

CONCLUSIONS

APA application following salvage neck dissections may reduce early postperative wound drainage and improve long-term skin quality.