Fatal intraoperative anaphylaxis related to aprotinin after local application of fibrin glue

Conjunctival Granulomas More Common than Recurrence in an 11-year Series of Pterygium Surgery

OBJECTIVES

To present an 11-year case series of pterygia.

METHODS

We conducted a retrospective case review of all pterygium surgeries performed at Dartmouth Hitchcock Medical Center between April 2011 and July 2022. Eighty-six cases were identified through a chart review identifying procedures with the code «Excision of Pterygium W/Transplant» on our electronic medical record system, obtained per a protocol approved by the Dartmouth-Hitchcock Health Human Research Protection Program (IRB study 02002030).

RESULTS

Of 86 cases, 84 were performed with conjunctival autografting (CAG) with fibrin glue, one was performed with just amniotic membrane transplant (AMT) with fibrin glue, and one was performed with both CAG and AMT with fibrin glue. No intraoperative mitomycin C or 5FU were used. Three patients with postoperative complications were identified, including two cases of postoperative conjunctival granulomas and one case of recurrent pterygium. Both conjunctival granulomas were treated with surgical excision without recurrence and sent to pathology for analysis. Histopathological findings are discussed herein. The recurrent pterygium was treated with 5FU injections, after which there were minimal symptoms and no progression at the last follow-up.

CONCLUSIONS

Although recurrence is the most commonly discussed complication of pterygium surgery, in our cases, over an 11-year span, we found that postoperative conjunctival granulomas were more common than recurrence.

In Vitro Evaluation of a Semi-Autologous Fibrin Sealant for Surgical Applications

Surgical success relies on precise tissue approximation using sutures, clips, or staples. Fibrin sealant provides a user-friendly alternative, saving time and maintaining tissue integrity. Yet, its cost and potential bioburden risk are notable drawbacks. To address these concerns, a semi-autologous fibrin sealant is produced from human cryoprecipitate and compared it to a commercial fibrin sealant. The microstructure of the semi-autologous sealant closely resembles the commercial one. Initially, the commercial sealant has superior bonding strength, however, over time, both demonstrate strong adhesive properties. Moreover, when the two sealants contain equivalent fibrinogen concentrations, they show similar bonding strength and rheological properties, including thixotropic behavior, which is essential for their application as bioadhesives. Notably, it is discovered that the mechanical properties of the adhesive are mainly governed by the fibrinogen concentration, with minimal impact of other blood components. This understanding paves the way for the development of an efficient method to boost fibrinogen in blood without extensive separation. This study indicates semi-autologous fibrin glue matches commercial sealant in adhesive properties. This may offer several advantages, such as reduced bioburden, costs, improved immunomodulation, and reduced hypersensitivity and virus transmission risks. These findings hold promising prospects for enhancing the wound healing process in various medical conditions.

Efficacy of Fibrin Sealant in Submental Liposuction: A Prospective Randomized Study

BACKGROUND

The incidence rate of submental liposuction has been increasing in recent years. Although this procedure is relatively simple, serious complications, including fatalities, have been reported, primarily owing to intraoperative and postoperative bleeding.

METHODS

To enhance the safety of liposuction, we examined the efficacy of Beriplast® P (CSL Behring, Melbourne, Australia), a physiological tissue adhesive fibrin sealant, in reducing postoperative swelling. Swelling was measured using the image analysis software VECTRA® (Vectra AI, Inc., CA, USA). Twenty-nine cases of submental liposuction performed from February to August 2024 were analyzed for tissue volume changes immediately postoperatively and at the time of suture removal, comparing those who received the fibrin sealant to those who did not.

RESULTS

The group using the fibrin sealant had significantly less postoperative swelling compared to the group that did not use the fibrin sealant (p<0.001).

CONCLUSIONS

The fibrin sealant may be used to effectively suppress postoperative swelling, reducing the risk of complications and improving patient satisfaction, thereby enhancing the overall safety and effectiveness of cosmetic surgery.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Phase 3, Randomized, Active-controlled, Single-blind Clinical Trial to Evaluate the Efficacy of Fibrin Sealant Grifols in Achieving Hemostasis in Pediatric Surgery

BACKGROUND

In this study, two fibrin sealant products, Fibrin Sealant Grifols (FS Grifols 80 mg/mL fibrinogen; 500 IU/mL thrombin) and Evicel (fibrinogen 55-85 mg/mL; thrombin 800-1200 IU/mL) were studied for efficacy in achieving hemostasis at a targeted bleeding site (TBS) on parenchymous or soft tissue in pediatric surgeries.

METHODS

This phase 3, single-blind, active comparator, non-inferiority trial compared the number of patients achieving hemostasis at a TBS at four (T4 - primary endpoint), seven (T7) and 10 (T10) minutes after application, Safety and tolerability were assessed by recording adverse events during and after procedures. Eligible patients were <18 years old undergoing elective, open, non-cardiac thoracic, abdominal or pelvic surgeries. Preterm (<37 weeks gestation) and newborn (0-27 days) infants were eligible.

RESULTS

At T4, 98.7% of FS Grifols group (n = 91) and 95.4% of the Evicel group (n = 87) achieved hemostasis. All patients with residual bleeding at T4 were undergoing soft tissue surgery. All patients achieved hemostasis by T7. At T10, all patients achieved hemostasis except one (FS Grifols (no observation recorded)). There were no incidents of persistent bleeding. For FS Grifols, 26.5% of patients had treatment-emergent adverse events (TEAEs) and 18.4% for Evicel. One TEAE (moderate procedural pain - FS Grifols group) was considered possibly related to study treatment. Three patients died for reasons unrelated to the study medications.

CONCLUSIONS

FS Grifols was safe and effective at achieving hemostasis in pediatric patients having parenchymous or soft tissue surgeries. The efficacy of FS Grifols was non-inferior to Evicel.

LEVEL OF EVIDENCE

I.

The use of Fibrin Sealants in Reducing Drain Output in Abdominoplasty: Is it Useful?

Background

Abdominoplasty is a common surgical procedure in which excess abdominal skin and fat are reduced to improve body contouring. Fibrin sealant has been proposed to reduce postsurgical bleeding and exudation. In this study, we evaluated whether there was a significant statistical difference in surgical output between the use of fibrin glue and its nonuse in abdominoplasty surgery, specifically in reducing bleeding and exudation.

Material and methods

A retrospective chart review of 68 postbariatric abdominoplasty patients (58 females, 10 males) was performed. We divided the patients into Group A (30 cases, 44%), in which we used fibrin sealant, and Group B (38 cases, 56%), in which we did not use fibrin glue. We calculated the total amount of liquid in suction drainages until the day of their removal. Statistical analysis included the independent t-test with a significance level of 0.05.

Results

The average drainage output in Group A was 620.0 ± 375.0 mL, whereas in Group B, it was 500.0 ± 290.0 mL. Results indicate an insignificant correlation between the use of fibrin glue and the amount of liquid in the surgical drains (t = 1.52, p = 0.13). The result is not significant at p <.05 according to the independent t-test.

Conclusion

The use of fibrin sealant surely has a high value in all surgical branches to reduce postoperative complications, but in our study, we did not find any advantages in its use for reducing surgical drain output in abdominoplasty patients.

Polyphosphate-loaded silk fibroin membrane as hemostatic agent in oral surgery: a pilot study

PURPOSE

Post-interventional hemorrhage can result in serious complications, especially in patients with hemostatic disorders. Identification of safe and efficient local hemostatic agents is important, particularly in the context of an ageing society and the emergence of new oral anticoagulants. The aim of this in vitro study was to investigate the potential of silk fibroin membranes coated with the inorganic polymer polyphosphate (polyP) as a novel hemostatic device in oral surgery.

METHODS

Cocoons of the silkworm Bombyx mori were degummed and dissolved. Varying amounts of long-chain polyP (2-2000 µg/mm2) were adsorbed to the surface of silk fibroin membranes. Analysis of the procoagulant effect of polyP-coated silk membranes was performed using real-time thrombin generation assays in human plasma. Increasing concentrations of polyP (0.15-500 µg/ml) served as a positive control, while uncoated silk fibroin membranes were used as negative control.

RESULTS

PolyP-coated silk fibroin membranes triggered coagulation when compared to plasma samples and pure silk fibroin membranes. A polyP-dose-dependent effect of thrombin generation could be found with a maximum (ETP = 1525.7 nM⋅min, peak thrombin = 310.1 nM, time to peak = 9.8 min, lag time = 7.6 min.) at 200 µg/mm2 of polymer loading on the silk fibroin membrane surface.

CONCLUSIONS

In this study, it was demonstrated that silk fibroin membranes coated with polyP have the potential to act as a promising novel hemostatic device.

Bioadhesive patch as a parenchymal sparing treatment of acute traumatic pulmonary air leaks

INTRODUCTION

Traumatic pulmonary injuries are common in chest trauma. Persistent air leaks occur in up to 46% of patients depending on injury severity. Prolonged leaks are associated with increased morbidity and cost. Prior work from our first-generation pectin patches successfully sealed pulmonary leaks in a cadaveric swine model. We now test the next-generation pectin patch against wedge resection in the management of air leaks in anesthetized swine.

METHODS

A continuous air leak of 10% to 20% percent was created to the anterior surface of the lung in intubated and sedated swine. Animals were treated with a two-ply pectin patch or stapled wedge resection (SW). Tidal volumes (TVs) were recorded preinjury and postinjury. Following repair, TVs were recorded, a chest tube was placed, and animals were observed for presence air leak at closure and for an additional 90 minutes while on positive pressure ventilation. Mann-Whitney U test and Fisher's exact test used to compare continuous and categorical data between groups.

RESULTS

Thirty-one animals underwent either SW (15) or pectin patch repair (PPR, 16). Baseline characteristics were similar between animals excepting baseline TV (SW, 10.3 mL/kg vs. PPR, 10.9 mL/kg; p = 0.03). There was no difference between groups for severity of injury based on percent of TV loss (SW, 15% vs. PPR, 14%; p = 0.5). There was no difference in TV between groups following repair (SW, 10.2 mL/kg vs. PPR, 10.2 mL/kg; p = 1) or at the end of observation (SW, 9.8 mL/kg vs. PPR, 10.2 mL/kg; p = 0.4). One-chamber intermittent air leaks were observed in three of the PPR animals, versus one in the SW group ( p = 0.6).

CONCLUSION

Pectin patches effectively sealed the lung following injury and were noninferior when compared with wedge resection for the management of acute traumatic air leaks. Pectin patches may offer a parenchymal sparing option for managing such injuries, although studies evaluating biodurability are needed.

Pectin based biologic Velcro effectively seals traumatic solid organ and small bowel injuries

INTRODUCTION

Injuries to the liver and small bowel are common in multiple injuries. While there are currently a variety of accepted damage-control techniques to expeditiously manage such injuries, morbidity and mortality remain high. Pectin polymers have previously been shown to effectively seal visceral organ injuries ex vivo through physiochemical entanglement with the glycocalyx. We sought to compare the standard of care for the management of penetrating liver and small bowel injuries with a pectin-based bioadhesive patch in a live animal model.

METHODS

Fifteen adult male swine underwent a laparotomy with standardized laceration to the liver. Animals were randomized to one of three treatment arms: packing with laparotomy pads (n = 5), suture repair (n = 5), or pectin patch repair (n = 5). Following 2 hours of observation, fluid was evacuated from the abdominal cavity and weighed. Next, a full-thickness small bowel injury was created, and animals were randomized to either a sutured repair (n = 7) or pectin patch repair (n = 8). The segment of bowel was then pressurized with saline, and the burst pressure was recorded.

RESULTS

All animals survived the protocol to completion. There were no clinically significant differences between groups regarding baseline vitals or laboratory studies. On one-way analysis of variance, there was a statistically significant difference between groups regarding blood loss after liver repair (26 mL suture vs. 33 mL pectin vs. 142 mL packing, p < 0.01). On post hoc analysis, there was no statistically significant difference between suture and pectin ( p = 0.9). After repair, small bowel burst pressures were similar between pectin and suture repair (234 vs. 224 mm Hg, p = 0.7).

CONCLUSION

Pectin-based bioadhesive patches performed similarly to the standard of care for the management of liver lacerations and full-thickness bowel injuries. Further testing is warranted to assess the biodurability of a pectin patch repair, as it may offer a simple option to effectively temporize traumatic intra-abdominal injuries.

Diagnosis and treatment evaluation in patients with spontaneous intracranial hypotension

Spontaneous intracranial hypotension is characterized by an orthostatic headache and audiovestibular symptoms alongside a myriad of other non-specific symptoms. It is caused by an unregulated loss of cerebrospinal fluid at the spinal level. Indirect features of CSF leaks are seen on brain imaging as signs of intracranial hypotension and/or CSF hypovolaemia as well as a low opening pressure on lumbar puncture. Direct evidence of CSF leaks can frequently, but not invariably, be observed on spinal imaging. The condition is frequently misdiagnosed due to its vague symptoms and a lack of awareness of the condition amongst the non-neurological specialities. There is also a distinct lack of consensus on which of the many investigative and treatment options available to use when managing suspected CSF leaks. The aim of this article is to review the current literature on spontaneous intracranial hypotension and its clinical presentation, preferred investigation modalities, and most efficacious treatment options. By doing so, we hope to provide a framework on how to approach a patient with suspected spontaneous intracranial hypotension and help minimize diagnostic and treatment delays in order to improve clinical outcomes.

Medical Adhesives and Their Role in Laparoscopic Surgery—A Review of Literature

Laparoscopic surgery is undergoing rapid development. Replacing the traditional method of joining cut tissues with sutures or staples could greatly simplify and speed up laparoscopic procedures. This alternative could undoubtedly be adhesives. For decades, scientists have been working on a material to bond tissues together to create the best possible conditions for tissue regeneration. The results of research on tissue adhesives achieved over the past years show comparable treatment effects to traditional methods. Tissue adhesives are a good alternative to surgical sutures in wound closure. This article is a review of the most important groups of tissue adhesives including their properties and possible applications. Recent reports on the development of biological adhesives are also discussed.

Fibrin Sealants: Challenges and Solutions

Intraoperative bleeding and postoperative bleeding are major surgical complications. Tissue sealants, hemostats, and adhesives provide the armamentarium for establishing hemostatic balance, including the tissue sealant fibrin. Fibrin sealants combine advantages including instantaneous effect, biocompatibility, and biodegradability. However, several challenges remain. This review summarizes current fibrin product generations and highlights new trends and potential strategies for future improvement.

Intraoperative anaphylaxis due to aprotinin after local application of fibrin sealant diagnosed by skin tests and basophil activation tests: a case report

Background

There are few cases of anaphylaxis after local application of fibrin sealant diagnosed by skin tests.

Case presentation

A 49-year-old woman underwent partial lung resection under general anesthesia. Anesthesia was induced uneventfully. Shortly after applying absorbable suture reinforcement felt that contained fibrin sealant, her systolic blood pressure fell to approximately 70 mmHg, along with facial flushing. Anaphylaxis was diagnosed based on the clinical symptoms and high serum tryptase levels. Three months after the event, skin tests were performed with all agents and were positive only for fibrin sealant vial no. 2, whose main component is aprotinin. Subsequently, basophil activation tests using fibrin sealant vial no. 2 and pure aprotinin demonstrated that the causative agent was likely aprotinin.

Conclusions

We diagnosed aprotinin-induced anaphylaxis using skin tests and basophil activation tests. The occurrence of anaphylaxis should be considered when changes in vital signs are observed after the use of fibrin sealant.

Review of topical gelatin-based haemostatic agents; an insidious culprit of intraoperative anaphylaxis?

BACKGROUND

An under-recognized complication of gelatin-based haemostatic agents is their potential to cause anaphylactic reactions. This review aims to collate and analyse case in the literature of intraoperative anaphylaxis secondary to locally applied haemostatic agents.

METHODS

An electronic search was performed on databases Medline, Embase, Pubmed and ProQuest. A total of 7671 articles were reviewed from title and abstract. After exclusion criteria and duplicates removed, 19 articles with 21 cases were included for analysis. Data extracted from each of the articles included patient demographics, haemostatic agent used, surgery type, known allergies and any objective evidence of hypersensitivity post anaphylactic episode, that is tryptase levels, IgE levels, skin prick testing.

RESULTS

Fifty-seven percent of cases involved patients <18 years of age; 57% of cases involved spinal surgery; 100% of cases displayed objective evidence of hypersensitivity (tryptase levels, bovine or porcine IgE levels, or skin prick testing). Thirty-three percent of patients had exposure preoperatively to a known agent causing anaphylaxis or allergy which would preclude the use of a gelatin-based haemostat. These products included vaccines, spam meats, red meat, Jell-O and CollaPlug. Gelatin-based haemostat agents included Floseal, Gelfoam, Surgiflo, fibrin glue, Avitene, haemofibrine sponge, topical bovine thrombin and thrombin-soaked gelatin.

CONCLUSION

Increased awareness of allergy to gelatin-based haemostats for surgical and anaesthetic is imperative, with 33% of cases having a known contraindication to gelatin-based haemostat. This review highlights important aspects in the pre-operative patient history and post-event patient investigation that could assist anaesthetists and surgeons in the prevention of future events.

A novel antimicrobial coating to prevent periprosthetic joint infection

Aims

Periprosthetic joint infection (PJI) is a debilitating condition with a substantial socioeconomic burden. A novel autologous blood glue (ABG) has been developed, which can be prepared during surgery and sprayed onto prostheses at the time of implantation. The ABG can potentially provide an antimicrobial coating which will be effective in preventing PJI, not only by providing a physical barrier but also by eluting a well-known antibiotic. Hence, this study aimed to assess the antimicrobial effectiveness of ABG when impregnated with gentamicin and stem cells.

Methods

Gentamicin elution from the ABG matrix was analyzed and quantified in a time-dependent manner. The combined efficiency of gentamicin and ABG as an anti-biofilm coating was investigated on titanium disks.

Results

ABG-gentamicin was bactericidal from 10 μg/ml and could release bactericidal concentrations over seven days, preventing biofilm formation. A concentration of 75 μg/ml of gentamicin in ABG showed the highest bactericidal effect up to day 7. On titanium disks, a significant bacterial reduction on ABG-gentamicin coated disks was observed when compared to both uncoated (mean 2-log reduction) and ABG-coated (mean 3-log reduction) disks, at days 3 and 7. ABG alone exhibited no antimicrobial or anti-biofilm properties. However, a concentration of 75 μg/ml gentamicin in ABG sustains release over seven days and significantly reduced biofilm formation. Its use as an implant coating in patients with a high risk of infection may prevent bacterial adhesion perioperatively and in the early postoperative period.

Conclusion

ABG’s use as a carrier for stem cells was effective, as it supported cell growth. It has the potential to co-deliver compatible cells, drugs, and growth factors. However, ABG-gentamicin’s potential needs to be further justified using in vivo studies.

Cite this article: Bone Joint Res 2020;9(12):848–856.

Comparison and application of commercially available fibrin sealants in ophthalmology

Fibrin glues carry many advantages over traditional suture as a tissue adhesive and have been increasingly used in a variety of ophthalmic procedures over the past 15 years. Several fibrin sealants are commercially available worldwide, each of which differs slightly in its composition and mechanism of delivery. The focus of our review is to briefly discuss the reported uses of fibrin in ophthalmic surgery and provide a broad overview of the properties associated with each commercially available fibrin sealant.

Feasibility of autologous fibrin glue in general thoracic surgery

Background

Fibrin glue effectively controls air leakage in lung surgery; however, allogenic fibrin glue cannot eliminate the risks of infection and allergy despite current sterilization methods. Autologous fibrin glue (AFG) could be a good alternative, but is not commonly used worldwide because of its limited availability and lack of evidence. Herein, we report clinical outcomes of AFG in thoracic surgery.

Methods

We retrospectively analyzed patients who underwent lobectomies or segmentectomies between November 2016 and September 2017 in our institution. We used two types of AFGs. One was a partially-autologous fibrin glue (PAFG), the components of which are largely autologous but which contains allogenic thrombin. The other was a completely-autologous fibrin glue (CAFG) which has no allogenic components. PAFG was used in the first half of the study period, after which CAFG was used from March 2017 onward. Patients who did not undergo AFG generation were categorized as the non-AFG group. The perioperative outcomes of the three groups were evaluated.

Results

A total of 207 patients underwent lung surgery, including 118 lobectomies and 89 segmentectomies. Among them, 83 patients received PAFG, 94 received CAFG, and 30 received non-AFG. The mean postoperative drainage period was within a few days in each group (PAFG vs. CAFG vs. non-AFG: 3.23±3.91 vs. 3.16±4.04 vs. 3.17±4.16 days, respectively; P=0.405), and the incidence of postoperative prolonged air leakage was within an acceptable range (PAFG vs. CAFG vs. non-AFG: 13.3% vs. 12.8% vs. 16.7%, respectively; P=0.821).

Conclusions

The use of AFG is clinically feasible for patients who undergo lobectomies or segmentectomies. AFGs could be a viable alternative to conventional allogenic fibrin glues.

Comparative epidemiology of suspected perioperative hypersensitivity reactions

Suspected perioperative hypersensitivity reactions are rare but contribute significantly to the morbidity and mortality of surgical procedures. Recent publications have highlighted the differences between countries concerning the respective risk of different drugs, and changes in patterns of causal agents and the emergence of new allergens. This review summarises recent information on the epidemiology of perioperative hypersensitivity reactions, with specific consideration of differences between geographic areas for the most frequently involved offending agents.

Use of a Sprayed Fibrin Hemostatic Sealant after Laser Therapy for Hereditary Hemorrhagic Telangiectasia Epistaxis

Background

Hereditary hemorrhagic telangiectasia (HHT) is a relatively common autosomal dominant condition. Epistaxis is a frequent manifestation, often occurring daily and requiring iron and blood transfusions. Surgery often is bloody and difficult. The aim of this study was to evaluate the effectiveness of a sprayed fibrin, hemostatic sealant in preventing postoperative epistaxis after laser treatment of nasal mucosa in HHT. Fibrin sealant was compared with nasal packing for likelihood of postoperative epistaxis and financial impact including material costs and hospitalization fees.

Methods

Retrospective review was performed of 64 individual laser treatments for epistaxis in HHT patients at the University of California, San Diego, Medical Center between 2002 and 2005. Nasal packing was used in 30 procedures and fibrin sealant was used in 34 procedures.

Results

Six of 30 (20%) procedures using postoperative nasal packing required admission with an average hospital expense of $5914. One of 34 patients (3%) in the fibrin sealant group required hospitalization (p = 0.04).

Conclusion

Aerosolized fibrin sealant prevents postoperative epistaxis after nasal laser treatment in HHT patients. Compared with traditional nasal packing we found improved patient comfort and recovery with substantial cost savings.

Native and synthetic scaffolds for limbal epithelial stem cell transplantation

Limbal stem cell deficiency (LSCD) is a complex blinding disease of the cornea, which cannot be treated with conventional corneal transplants. Instead, a stem cell (SC) graft is required to replenish the limbal epithelial stem cell (LESC) reservoir, which is ultimately responsible for regenerating the corneal epithelium. Current therapies utilize limbal tissue biopsies that harbor LESCs as well as tissue culture expanded cells. Typically, this tissue is placed on a scaffold that supports the formation of corneal epithelial cell sheets, which are then transferred to diseased eyes. A wide range of biological and synthetic materials have been identified as carrier substrates for LESC, some of which have been used in the clinic, including amniotic membrane, fibrin, and silicon hydrogel contact lenses, each with their own advantages and limitations. This review will provide a brief background of LSCD, focusing on bio-scaffolds that have been utilized in limbal stem cell transplantation (LSCT) and materials that are being developed as potentially novel therapeutics for patients with this disease.

STATEMENT OF SIGNIFICANCE

The outcome of patients with corneal blindness that receive stem cell grafts to restore eye health and correct vision varies considerably and may be due to the different biological and synthetic scaffolds used to deliver these cells to the ocular surface. This review will highlight the positive attributes and limitations of the myriad of carriers developed for clinical use as well as those that are being trialled in pre-clinical models. The overall focus is on developing a standardized therapy for patients, however due to the multiple causes of corneal blindness, a personal regenerative medicine approach may be the best option.

Efficacy, Reliability, and Safety of Completely Autologous Fibrin Glue in Neurosurgical Procedures: Single-Center Retrospective Large-Number Case Study

OBJECTIVE

Commercially available fibrin glue (Com-FG), which is used commonly worldwide, is produced with pooled human plasma from multiple donors. However, it has added bovine aprotinin, which involves the risk of infection, allogenic immunity, and allergic reactions. We evaluate the efficacy, reliability, and safety of completely autologous fibrin glue (CAFG).

METHODS

From August 2014 to February 2016, prospective data were collected and analyzed from 153 patients. CAFG was prepared with the CryoSeal System using autologous blood and was applied during neurosurgical procedures. Using CAFG-soaked oxidized regenerated cellulose and/or polyglycolic acid sheets, we performed a pinpoint hemostasis, transposed the offending vessels in a microvascular decompression, and covered the dural incision to prevent cerebrospinal fluid leakage.

RESULTS

The CryoSeal System had generated up to a mean of 4.51 mL (range, 3.0-8.4 mL) of CAFG from 400 mL autologous blood. Com-FG products were not used in our procedures. Only 6 patients required an additional allogeneic blood transfusion. The hemostatic effective rate was 96.1% (147 of 153 patients). Only 1 patient who received transsphenoidal surgery for a pituitary adenoma presented with the complication of delayed postoperative cerebrospinal fluid leakage (0.65%). No patient developed allergic reactions or systemic complications associated with the use of CAFG.

CONCLUSIONS

CAFG effectively provides hemostatic, adhesive, and safety performance. The timing and three-dimensional shape of CAFG-soaked oxidized regenerated cellulose and/or polyglycolic acid sheets solidification can be controlled with slow fibrin formation. The cost to prepare CAFG is similar compared with Com-FG products, and it can therefore be easily used at most institutions.

Novel synthetic adhesive as an effective alternative to Fibrin based adhesives

AIM

To compare a novel, fully synthetic, polyurethane based glue (MAR-1) to fibrin sealant in a partial liver resection rat model.

METHODS

After 50% resection of the lateral left liver lobe in male Wistar rats (n = 7/group/time point), MAR-1, Fibrin or NaCl was applied. After 14, 21 and 90 postoperative days, sealant degradation, intra-abdominal adhesions were scored, and histological examination of liver tissue was performed.

RESULTS

(Mean ± SEM) (MAR-1 vs Fibrin vs NaCl). Bleeding mass was significantly higher in NaCl (3.36 ± 0.51 g) compared to MAR-1 (1.44 ± 0.40 g) and Fibrin (1.16 ± 0.32 g). At 14 and 90 d, bleeding time was significantly lower in MAR-1 (6.00 ± 0.9 s; 13.57 ± 3.22 s) and Fibrin (3.00 ± 0.44 s; 22.2 ± 9.75 s) compared to NaCl (158.16 ± 11.36 s; 127.5 ± 23.3 s). ALT levels were significantly higher in MAR-1 (27.66 ± 1 U/L) compared to Fibrin (24.16 ± 0.98 U/L) and NaCl (23.85 ± 0.80 U/L). Intrabdominal adhesions were significantly lower in MAR-1 (11.22% ± 5.5%) compared to NaCl (58.57% ± 11.83%). Degradation of the glue was observed and MAR-1 showed almost no traces of glue in the abdominal cavity as compared to the Fibrin (10% ± 5% 14 d; 7% ± 3% 21 d). Survival showed no significant differences between the groups.

CONCLUSION

Compared to Fibrin, MAR-1 showed similar hemostatic properties, no adverse effects, and is biocompatible. Further studies on adhesion strength and biodegradability of synthetic sealants are warranted.

Sutureless, Glue-less Conjunctival Autograft versus Conjunctival Autograft with Sutures for Primary, Advanced Pterygia: An Interventional Pilot study

INTRODUCTION

Conjunctival Autograft (CAG) in pterygium surgery can be attached by sutures or fibrin glue or autologous in situ blood coagulum. Recurrence rate and other parameters related to pterygium surgery between CAG with sutures and autologous in situ blood coagulum have not been compared uniformly in advanced pterygia alone.

AIM

To compare and evaluate the outcome of sutureless, glue-less CAG with autologous in situ blood coagulum versus CAG with sutures for primary, advanced pterygium.

MATERIALS AND METHODS

Thirty eyes of 30 patients with primary, nasal, advanced, Grade 3 pterygia (as per Tan et al's., classification) were randomized into Group 1 (n=15) (sutureless, glue-less CAG with autologous in situ blood coagulum) and Group 2 (n=15) (conjunctival autograft with 8-0 vicryl sutures) as a pilot study. The outcome parameters evaluated were graft stability and symptoms of pain, foreign body sensation and watering at day 1, day 7, day 14, one month, three months and six months and recurrence at six months.

RESULTS

The mean age in the study was 44.77±13.74 years. Overall, Group 1 had better scores in symptom parameters than Group 2 (p<0.05). Graft stability was better in Group 2 (p<0.05). In Group 1, 3 (20%) patients had one side displacement and 3 (20%) patients had full displacement of graft. At six months, 4 (26.6%) patients in Group 1 had recurrence whereas in Group 2, 5 patients (33.3%) had recurrence (p=0.446).

CONCLUSION

In primary, advanced pterygia, sutureless, glue-less pterygium surgery with autologous in situ blood coagulum was better in symptom scores but graft stability was better in the suture group. Sutureless, glue-less pterygium surgery with autologous in situ blood coagulum was unpredictable in graft stability. There was no statistically significant difference in the recurrence rate between the two groups.

Safety of Cultivated Limbal Epithelial Stem Cell Transplantation for Human Corneal Regeneration

Ex vivo cultivated limbal stem cell transplantation is a promising technique for the treatment of limbal stem cell deficiency. While the results of the clinical trials have been extensively reported since the introduction of the technique in 1997, little has been reported regarding the potential health risks associated with production processes and transplantation techniques. Culture procedures require the use of animal and/or human-derived products, which carry the potential of introducing toxic or infectious agents through contamination with known or unknown additives. Protocols vary widely, and the risks depend on the local institutional methods. Good manufacturing practice and xeno-free culture protocols could reduce potential health risks but are not yet a common practice worldwide. In this review, we focus on the safety of both autologous- and allogeneic-cultivated limbal stem cell transplantation, with respect to culture processes, surgical approaches, and postoperative strategies.

Applications of Fibrin Sealant in Surgery

Fibrin sealant has been used with increasing frequency in a variety of surgical field for its unique hemostatic and adhesive abilities. Fibrin sealant mimics the last step of the coagulation cascade and takes place independently of the patient's coagulation status. With rapid advances in minimally invasive surgery, the potential uses for this type of biologic and synthetic material are expanding exponentially. This article reviews the data associated with the application of fibrin sealant in various surgical procedures. From reinforcing gastrointestinal anastomosis to repair perforated duodenal ulcers to mesh fixation in laparoscopic inguinal hernia repair, fibrin sealant is gaining increasing acceptance among surgeons. The applications of fibrin sealant are expanding, and new preparations of fibrin sealant are currently being evaluated.

Clinical evaluations of autologous fibrin glue and polyglycolic acid sheets as oral surgical wound coverings after partial glossectomy

Polyglycolic acid (PGA) sheets and commercial fibrin glue are commonly used to cover open wound surfaces in oral surgery. Compared to commercial fibrin glue composed of pooled allogeneic blood, autologous fibrin glue is less expensive and poses lower risks of viral infection and allergic reaction. Here, we evaluated postoperative pain, scar contracture, ingestion, tongue dyskinesia, and postoperative bleeding in 24 patients who underwent partial glossectomy plus the application of a PGA sheet and an autologous fibrin glue covering (autologous group) versus 11 patients in whom a PGA sheet and commercial fibrin glue were used (allogeneic group). The evaluated clinical measures were nearly identical in both groups. Remarkable wound surface granulation was recognized in two cases in the autologous group. No complications were observed in either group, including viral infection or allergic reaction. Abnormal postoperative bleeding in the wound region was observed in one case in the allogeneic group. Coagulation and adhesion of the autologous fibrin glue were equivalent to those of conventional therapy with a PGA sheet and commercial fibrin glue. Thus, our results show that covering wounds with autologous fibrin glue and PGA sheets may help avoid the risks of viral infection and allergic reaction in partial glossectomy cases.

Ophthalmic use of blood-derived products

There is a wide spectrum of blood-derived products that have been used in many different medical and surgical specialties with success. Blood-derived products for clinical use can be extracted from autologous or allogeneic specimens of blood, but recombinant products are also commonly used. A number of blood derivatives have been used for a wide range of ocular conditions, from the ocular surface to the retina. With stringent preparation guidelines, the potential risk of transmission of blood-borne diseases is minimized. We review blood-derived products and how they are improving the management of ocular disease.

Hypersensitivity to sub-Tenon's topotecan in fibrin adhesive in patients with retinoblastoma

Sub-Tenon's space delivery of topotecan in a fibrin sealant was used as an adjunct to laser therapy for small retinoblastoma tumors in 25 children (77 injections). We report serious hypersensitivity reactions in 2 children on their third sub-Tenon's injection of topotecan in fibrin sealant. One child subsequently had topotecan in an autologous blood clot with no allergic reaction. Although allergic reaction to topotecan has been reported in the literature, fibrin glue reactions are more common and are likely due to aprotinin hypersensitivity.

Comparison between sutureless and glue free versus sutured limbal conjunctival autograft in primary pterygium surgery

PURPOSE

To compare and evaluate the safety and efficacy of two surgical techniques for the management of primary pterygium.

DESIGN

Prospective randomized clinical trial using the CONSORT 2010 Statement (Consolidated Standards of Reporting Trials) for parallel group randomized trials.

SETTING

Department of Ophthalmology, Al-Minya University, Faculty of Medicine, Egypt.

METHODS

The study included 150 eyes of 150 patients with primary pterygium. The mean age was 49 ± 12 years (range 24-74 years). Simple excision under local anesthesia was performed followed by closure of the bare sclera by suture less and glue free conjunctival autograft in 50 eyes of 50 patients (group 1), versus the conventional method of a sutured conjunctival autograft in 100 eyes of 100 patients (group 2).

RESULTS

The pterygium recurrence rate was 6% for group 1, 8% for group 2. Graft dehiscence occurred in 4 eyes out of 50 (8%) in group 1. Graft retraction occurred in 6 (12%) out of 50 eyes for group 1 versus 6 eyes (6%) in group 2. Pyogenic granuloma occurred in 3 (3%) eyes out of 100 in group 2. No other serious complications were noted. At the 3 week visit the overall patient satisfaction score was statistically significantly higher for group 1 (P < 0.002) compared to group 2. At 3 months postoperatively, the gain in uncorrected visual acuity (UCVA) ranged from 0.2 to 0.5 Log MAR in 10 eyes.

CONCLUSION

Sutureless and glue free conjunctival autograft technique is easy, safe, effective, prevents potential adverse reactions encountered with the use of foreign materials. This technique has an acceptable pterygium recurrence rate that is comparable to conventional sutured conjunctival autograft for primary pterygium.

Prospective randomized controlled trial: fibrin sealant reduces split skin graft donor-site pain

BACKGROUND

Pain at split skin graft donor sites is common. Fibrin sealant has been demonstrated to reduce time to hemostasis at wound sites, and patients receiving this treatment were incidentally noted to report less pain. This study aimed to evaluate pain and incapacity in split skin graft donor sites treated with and without fibrin sealant.

METHODS

Fifty patients requiring thigh donor-site split skin grafts were prospectively randomized to receive either a self-adhesive fabric dressing alone or fibrin sealant plus the self-adhesive fabric dressing as primary donor-site dressings. External secondary dressings were the same. Patients were blinded with regard to treatment group. Using visual analogue scales (scored 0 to 5), patients rated their donor-site pain and incapacity for 14 days postoperatively. Secondary endpoints were length of hospital stay and duration of requirement for dressings.

RESULTS

Forty patients were included in the study analysis and completed self-reported pain and incapacity scores. Twenty received the fibrin sealant plus self-adhesive fabric dressing and 20 received the fabric dressing only (controls). Patients using the fibrin sealant plus the dressing reported significantly less pain (mean score, 0.42 versus 1.60, p < 0.001) and significantly less incapacity (mean score, 0.48 versus 1.71, p < 0.001). Patients allocated to the fibrin sealant group recorded shorter lengths of stay and faster time to discontinuation of dressing, though statistical significance was not achieved.

CONCLUSION

Patients whose split skin graft donor sites were dressed with fibrin sealant plus self-adhesive fabric dressing experienced significantly less pain and incapacity than patients with self-adhesive fabric dressings alone, allowing a more rapid return to normal activity.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Conjunctival autografting without fibrin glue or sutures for pterygium surgery

PURPOSE

A prospective randomized case-control study conducted at a tertiary level eye care center to compare the outcomes of conjunctival autograft (CAG) with fibrin glue and CAG with patients' own blood acting as a bioadhesive in treating pterygium after surgical excision.

METHODS

Twenty eyes of 20 patients with pterygium were randomly divided into 2 groups: group I (10 eyes) underwent CAG with fibrin glue and group II (10 eyes) underwent CAG with the patients' own blood coagulum acting as a bioadhesive or fixative.

RESULTS

The time required for the surgery was compared. The patients were then closely followed up for a period of 12 months for anatomy, outcomes of graft, recurrence rate, graft displacement, retraction, inflammatory reaction, if any, graft failure, or any other complications. The duration of surgery was less in group I (mean duration, 14.74 ± 2.35 minutes) than group II (mean duration, 17.45 ± 2.89 minutes). We found that although the rate of recurrences was equal in grafts with the glue (10%) and the grafting with autologous blood (10%), the complications regarding graft displacement and graft retraction were more common in patients with grafting with autologous blood (10%) than in those with grafting with the glue. However, the difference was not found to be statistically significant (P = 0.3185). These complications were associated with larger grafts.

CONCLUSIONS

This study suggests that autologous fibrin in blood is a useful alternative method for graft fixation in pterygium surgery. We found the newer procedure of autografing free of any untoward complication in small- to average-sized grafts.

A method to screen and evaluate tissue adhesives for joint repair applications

BACKGROUND

Tissue adhesives are useful means for various medical procedures. Since varying requirements cause that a single adhesive cannot meet all needs, bond strength testing remains one of the key applications used to screen for new products and study the influence of experimental variables. This study was conducted to develop an easy to use method to screen and evaluate tissue adhesives for tissue engineering applications.

METHOD

Tissue grips were designed to facilitate the reproducible production of substrate tissue and adhesive strength measurements in universal testing machines. Porcine femoral condyles were used to generate osteochondral test tissue cylinders (substrates) of different shapes. Viability of substrates was tested using PI/FDA staining. Self-bonding properties were determined to examine reusability of substrates (n = 3). Serial measurements (n = 5) in different operation modes (OM) were performed to analyze the bonding strength of tissue adhesives in bone (OM-1) and cartilage tissue either in isolation (OM-2) or under specific requirements in joint repair such as filling cartilage defects with clinical applied fibrin/PLGA-cell-transplants (OM-3) or tissues (OM-4). The efficiency of the method was determined on the basis of adhesive properties of fibrin glue for different assembly times (30 s, 60 s). Seven randomly generated collagen formulations were analyzed to examine the potential of method to identify new tissue adhesives.

RESULTS

Viability analysis of test tissue cylinders revealed vital cells (>80%) in cartilage components even 48 h post preparation. Reuse (n = 10) of test substrate did not significantly change adhesive characteristics. Adhesive strength of fibrin varied in different test settings (OM-1: 7.1 kPa, OM-2: 2.6 kPa, OM-3: 32.7 kPa, OM-4: 30.1 kPa) and was increasing with assembly time on average (2.4-fold). The screening of the different collagen formulations revealed a substance with significant higher adhesive strength on cartilage (14.8 kPa) and bone tissue (11.8 kPa) compared to fibrin and also considerable adhesive properties when filling defects with cartilage tissue (23.2 kPa).

CONCLUSION

The method confirmed adhesive properties of fibrin and demonstrated the dependence of adhesive properties and applied settings. Furthermore the method was suitable to screen for potential adhesives and to identify a promising candidate for cartilage and bone applications. The method can offer simple, replicable and efficient evaluation of adhesive properties in ex vivo specimens and may be a useful supplement to existing methods in clinical relevant settings.

Adverse effects of fibrin sealants in thoracic surgery: the safety of a new fibrin sealant: multicentre, randomized, controlled, clinical trial

OBJECTIVES

The safety of fibrin sealants (FS) has been questioned in the light of recent reports of adverse effects. We evaluated the safety of a new FS in a randomized controlled trial (RCT).

METHODS

Multicentre, open-label Phase II/III RCT to evaluate the safety of the new FS. The trial was approved by the Ethic Committee of each three participating Centre. FS includes two components (component 1: fibrinogen; component 2: thrombin), each of them subjected to two viral inactivation procedures. Out of 200 screened patients, 185 eligible patients (49 females, 136 males), aged between 18 and 75 years, undergoing major thoracic surgery were randomized to receive FS (#91 patients) as an adjuvant for air leak control or no treatment (#94 patients, control group). Safety variables were: percentage of subjects with adverse events associated with the therapy; formation of antibodies against bovine aprotinin; vital signs (blood pressure, body temperature, heart and respiratory rate); laboratory parameters.

RESULTS

Overall operative mortality was 3.2% (6/185), 1.1% in the FS group and 5.3% in the control group, respectively. Twenty patients (22%) had adverse events in the FS group and 22 (23.4%) in the control group. Atrial fibrillation (five patients in the FS group and four in the control group) and hyperpyrexia (five and seven patients, respectively, in the two groups) were the most common adverse events. No patient reported thromboembolic events (pulmonary embolism or deep vein thrombosis) during the in hospital stay or within 1 month from discharge. None of the adverse events was considered as treatment related. The formation of bovine aprotinin antibodies was reported in a total of 34 patients (37.4%) in the FS group and was not related to any adverse effect.

CONCLUSIONS

The present RCT did not show any increased risk of adverse events, and of surgical complications, related to the use of the new FS.

Allogeneic single-donor cryoseal produced from fresh-frozen quarantine apheresis plasma as alternative for multidonor or autologous fibrin sealants

BACKGROUND

Fibrin sealant is a human blood product consisting of two components: cryoprecipitate and thrombin. Commercial fibrin sealants are produced from multidonors, increasing the viral risk, and contain fibrinolytic inhibitors such as tranexamic acid or bovine aprotinin. Autologous fibrin sealants reduce the viral risk and are mostly produced during a surgical procedure or well in advance. Alternatively, the allogeneic single-donor fibrin sealant cryoseal can be used. In this study cryoseal was characterized and the manufacturing consistency of the production process was investigated.

STUDY DESIGN AND METHODS

Cryoseal was produced from plasma collected on apheresis machines using a commercial device. In a research setting the protein composition and recovery were determined. Also, the manufacturing consistency of the production process was tested in a research setting as well as in a routine setting.

RESULTS

In the research setting all produced cryoseal met the quality control requirements of a clotting time of less than 10 seconds and the presence of Factor (F)XIII (qualitative). In the routine setting, one procedure per year did not meet these requirements. The protein composition showed the following mean ± standard deviation (%recovery) results: thrombin 25.7 ± 11.1 IU/mL, fibrinogen 19.9 ± 4.6 (15%) mg/mL, FVIII 15.6 ± 5.4 (44%) IU/mL, FXIII 2.7 ± 0.7 (6%) IU/mL, and plasminogen 1.8 ± 0.2 (4%) U/mL. In both research and routine settings the production process resulted in a consistent product.

CONCLUSION

The cryoseal manufacturing process resulted in a consistent product, which meets the predetermined specifications. The single-donor origin and the absence of fibrinolytic inhibitors make cryoseal a good alternative for multidonor and autologous fibrin sealants.