Evolution of hemostatic agents in surgical practice

Injectable, Antibacterial, and Hemostatic Tissue Sealant Hydrogels

Hemorrhage and bacterial infections are major hurdles in the management of life-threatening surgical wounds. Most bioadhesives for wound closure lack sufficient hemostatic and antibacterial properties. Furthermore, they suffer from weak sealing efficacy, particularly for stretchable organs, such as the lung and bladder. Accordingly, there is an unmet need for mechanically robust hemostatic sealants with simultaneous antibacterial effects. Here, an injectable, photocrosslinkable, and stretchable hydrogel sealant based on gelatin methacryloyl (GelMA), supplemented with antibacterial zinc ferrite (ZF) nanoparticles and hemostatic silicate nanoplatelets (SNs) for rapid blood coagulation is nanoengineered. The hydrogel reduces the in vitro viability of Staphylococcus aureus by more than 90%. The addition of SNs (2% w/v) and ZF nanoparticles (1.5 mg mL-1 ) to GelMA (20% w/v) improves the burst pressure of perforated ex vivo porcine lungs by more than 40%. Such enhancement translated to ≈250% improvement in the tissue sealing capability compared with a commercial hemostatic sealant, Evicel. Furthermore, the hydrogels reduce bleeding by ≈50% in rat bleeding models. The nanoengineered hydrogel may open new translational opportunities for the effective sealing of complex wounds that require mechanical flexibility, infection management, and hemostasis.

Reviewing the Impact of Topical and Intravenous Tranexamic Acid Use in Breast Plastic Surgery

BACKGROUND

Topical and intravenous uses of tranexamic acid (TXA) have been shown to reduce bleeding and ecchymosis in various surgical fields. However, there is a lack of data evaluating the efficacy of TXA in breast surgery. This systematic review evaluates the impact of TXA on hematoma and seroma incidence in breast plastic surgery.

METHODS

A systematic review of the literature was performed for all studies that evaluated the use of TXA in breast surgery including reduction mammoplasty, gynecomastia surgery, masculinizing chest surgery, or mastectomy. Outcomes of interest included rate of hematoma, seroma, and drain output.

RESULTS

Thirteen studies met the inclusion criteria with a total of 3297 breasts, of which 1656 were treated with any TXA, 745 with topical TXA, and 1641 were controls. There was a statistically significant decrease in hematoma formation seen in patients who received any form of TXA compared with control (odds ratio [OR], 0.37; P < 0.001), and a similar tendency toward decreased hematoma with topically treated TXA (OR, 0.42; P = 0.06). There was no significant difference in seroma formation with any TXA (OR, 0.84; P = 0.33) or topical TXA (OR, 0.91; P = 0.70). When stratified by surgery, there was a 75% decrease in the odds of hematoma formation with any TXA compared with the control for oncologic mastectomy (OR, 0.25; P = 0.003) and a 56% decrease in nononcologic breast surgery (OR, 0.44; P = 0.003).

CONCLUSIONS

This review suggests that TXA may significantly reduce hematoma formation in breast surgery and may also decrease seroma and drain output. Future high-quality prospective studies are required to evaluate the utility of topical and intravenous TXA in decreasing hematoma, seroma, and drain output in breast surgery patients.

Advances in haemostatic sponges: Characteristics and the underlying mechanisms for rapid haemostasis

In traumatized patients, the primary cause of mortality is uncontrollable continuous bleeding and unexpected intraoperative bleeding which is likely to increase the risk of complications and surgical failure. High expansion sponges are effective clinical practice for the treatment of wound bleeding (irregular/deep/narrow) that are caused by capillaries, veins and even arterioles as they possess a high liquid absorption ratio so can absorb blood platelets easily in comparison with traditional haemostasis treatments, which involve compression, ligation, or electrical coagulation etc. When in contact with blood, haemostatic sponges can cause platelet adhesion, aggregation, and thrombosis, preventing blood from flowing out from wounds, triggering the release of coagulation factors, causing the blood to form a stable polymerized fibre protein, forming blood clots, and achieving the goal of wound bleeding control. Haemostatic sponges are found in a variety of shapes and sizes. The aim of this review is to facilitate an overview of recent research around haemostatic sponge materials, products, and technology. This paper reviews the synthesis, properties, and characteristics of haemostatic sponges, together with the haemostasis mechanisms of haemostatic sponges (composite materials), such as chitosan, cellulose, gelatin, starch, graphene oxide, hyaluronic acid, alginate, polyethylene glycol, silk fibroin, synthetic polymers silver nanoparticles, zinc oxide nanoparticles, mesoporous silica nanoparticles, and silica nanoparticles. Also, this paper reviews commercial sponges and their properties. In addition to this, we discuss various in-vitro/in-vivo approaches for the evaluation of the effect of sponges on haemostasis.

Short Peptide Nanofiber Biomaterials Ameliorate Local Hemostatic Capacity of Surgical Materials and Intraoperative Hemostatic Applications in Clinics

Short designer self-assembling peptide (dSAP) biomaterials are a new addition to the hemostat group. It may provide a diverse and robust toolbox for surgeons to integrate wound microenvironment with much safer and stronger hemostatic capacity than conventional materials and hemostatic agents. Especially in noncompressible torso hemorrhage (NCTH), diffuse mucosal surface bleeding, and internal medical bleeding (IMB), with respect to the optimal hemostatic formulation, dSAP biomaterials are the ingenious nanofiber alternatives to make bioactive neural scaffold, nasal packing, large mucosal surface coverage in gastrointestinal surgery (esophagus, gastric lesion, duodenum, and lower digestive tract), epicardiac cell-delivery carrier, transparent matrix barrier, and so on. Herein, in multiple surgical specialties, dSAP-biomaterial-based nano-hemostats achieve safe, effective, and immediate hemostasis, facile wound healing, and potentially reduce the risks in delayed bleeding, rebleeding, post-operative bleeding, or related complications. The biosafety in vivo, bleeding indications, tissue-sealing quality, surgical feasibility, and local usability are addressed comprehensively and sequentially and pursued to develop useful surgical techniques with better hemostatic performance. Here, the state of the art and all-round advancements of nano-hemostatic approaches in surgery are provided. Relevant critical insights will inspire exciting investigations on peptide nanotechnology, next-generation biomaterials, and better promising prospects in clinics.

The effect of different hemostatic agents following dental extraction in patients under oral antithrombotic therapy: a network meta-analysis

This network meta-analysis was done to thoroughly evaluate the available literature on the use of different hemostatic agents for dental extraction in patients under oral antithrombotic therapy, aiming to identify the agent with the best/worst performance in bleeding control. Considering that such patients have a higher risk of bleeding, choosing the right hemostatic is essential. Twenty-three randomized clinical trials articles were included after completing the literature search. Cyanoacrylate tissue adhesive showed a reduction in the odds of postoperative bleeding events compared with conventional methods (i.e., gauze/cotton pressure, sutures), with a tendency toward a statistical significance (OR 0.03, P = 0.051). Tranexamic acid was the only agent that demonstrated a significantly lower risk of developing postoperative bleeding events (OR 0.27, P = 0.007). Interestingly, chitosan dental dressing and collagen plug had the shortest time to reach hemostasis. However, they ranked last among all hemostatic agents, regarding bleeding events, revealing higher odds than conventional measures. Therefore, it is concluded that the use of cyanoacrylate tissue adhesive and tranexamic acid gives favorable results in reducing postoperative bleeding events following dental extractions. Although chitosan dental dressing and collagen exhibited a faster time to reach hemostasis, they led to a higher occurrence of bleeding events.

The novel use and feasibility of hemostatic oxidized regenerated cellulose agent (SurgiGuard®): multicenter retrospective study

Background

SurgiGuard® is an absorbent hemostatic agent based on oxidized regenerated cellulose. The efficacy, effects and safety of SurgiGuard® are equivalent to existing hemostatic agents in animal experiments. This study was designed to confirm that the use of SurgiGuard® alone is effective, safe and feasible compared to combination with other hemostatic methods.

Methods

We retrospectively reviewed clinical data from 12 surgery departments in seven tertiary centers in South Korea nationwide. All surgeries were performed between January and December 2018.

Results

A total of 807 patients were enrolled; 447 patients (55.4%) had comorbidities. The rate of major surgery (operative time ≥4 hours) was 44% (n=355 patients). Regarding the type of SurgiGuard® used in surgery, more than 70% of minor surgeries used non-woven types. In major surgery, more than five SurgiGuards® were used in 7.3% (26 patients), and the proportion of co-usage (with four other hemostatic products) was 19.7% (70 patients). The effectiveness score was higher when SurgiGuard® was used alone in both major (5.3±0.5 vs. 5.1±0.6, P=0.048) and minor surgery (5.4±0.6 vs. 5.2±0.4, P<0.001). Seven patients had immediate re-bleeding, and all of them used SurgiGuard® and other products together. Nine patients reported adverse effects, such as abscess, bleeding, or leg swelling, but we found no direct correlation with SurgiGuard®.

Conclusions

SurgiGuard® exhibited greater effectiveness when used alone. No direct adverse effects associated with SurgiGuard® use were reported, and SurgiGuard® had stable feasibility. Prospective comparative studies are needed in the future.

The role of hemostatic agents after tooth extractions: A systematic review and meta-analysis

BACKGROUND

Hemostatic agents are used to control bleeding after tooth extraction and have been compared with conventional measures (that is, sutures or gauze pressure) in several studies. The objective of this systematic review was to evaluate the benefits of topical hemostatic agents for controlling bleeding after tooth extractions, especially in patients receiving antithrombotic therapy.

TYPES OF STUDIES REVIEWED

The authors conducted a literature search in MEDLINE (PubMed), Scopus, and the Cochrane Central Register of Controlled Trials, including prospective human randomized clinical trials in which researchers compared hemostatic agents with conventional methods and reported the time to achieve hemostasis and postoperative bleeding events.

RESULTS

Seventeen articles were eligible for inclusion. Hemostatic agents resulted in a significantly shorter time to achieve hemostasis in both healthy patients and patients taking antithrombotic drugs (standardized mean difference, -1.02; 95% CI, -1.70 to -0.35; P = .003 and standardized mean difference, -2.30; 95% CI, -3.20 to -1.39; P < .00001, respectively). Significantly fewer bleeding events were noted when hemostatic agents were used (risk ratio, 0.62; 95% CI, 0.44 to 0.88; P = .007). All forms of hemostatic agents (that is, mouthrinse, gel, hemostatic plug, and gauze soaked with the agent) had better efficacy in reducing the number of postoperative bleeding events than conventional hemostasis measures, except for hemostatic sponges. However, this was based on a small number of studies in each subgroup.

CONCLUSIONS

The use of hemostatic agents seemed to offer better bleeding control after tooth extractions in patients on antithrombotic drugs than conventional measures.

PRACTICAL IMPLICATIONS

Findings of this systematic review may help clinicians attain more efficient hemostasis in patients requiring tooth extraction. This systematic review is registered in the PROSPERO database. The registration number is CRD42021256145.

Effect of Gelatin-Based Hemostats on Fibroblasts and Relevant Growth Factors in Wound Healing

Gelatin-based hemostats have been used in various surgical fields and showed advantageous effects on central aspects of wound healing when compared to cellulose-based hemostats. Nevertheless, the influence of gelatin-based hemostats on wound healing has not been fully explored yet. Hemostats were applied to fibroblast cell cultures for 5, 30, 60 min, 24 h, 7 and 14 days and measurements were taken at 3, 6, 12, 24 h and 7 or 14 days, respectively. Cell proliferation was quantified after different exposure times and a contraction assay was conducted to measure the extent of the extracellular matrix over time. We further assessed quantitative levels of vascular endothelial growth factor and basic fibroblast growth factor using enzyme-linked immunosorbent assay. Fibroblast counts decreased significantly at 7 and 14 days independent of the application duration (p < 0.001 for 5 min application). The gelatin-based hemostat did not have a negative impact on cell matrix contraction. After application of gelatin-based hemostat, the basic fibroblast growth factor did not change; yet, the vascular endothelial growth factor significantly increased after a prolonged 24 h application time when compared to controls or to a 6 h exposure (p < 0.05). Gelatin-based hemostats did not impair contraction of the extracellular matrix or growth factor production (vascular endothelial growth factor and basic fibroblast growth factor), while cell proliferation diminished at late time points. In conclusion, the gelatin-based material seems to be compatible with central aspects of wound healing. For further clinical assessment, future animal and human studies are necessary.

Defining the incidence and management of postoperative scrotal hematoma after primary and complex three-piece inflatable penile prosthesis surgery

Scrotal hematoma is a challenging complication of penile prosthesis surgery. We characterize the risk of hematoma formation with implementation of standardized techniques to mitigate hematomas and assess for any associated factors in a large multi-institutional penile implant cohort. This was a retrospective review from February 2018 to December 2020 of all patients who underwent inflatable penile prosthesis implantation at 2 high volume implant centers. Cases were defined as "complex" if they involved revision, salvage with removal/replacement, or were performed with concurrent penile, scrotal or intra-abdominal surgeries. The incidence of scrotal hematoma among primary and complex IPP recipients was measured and modifiable and innate risk factors associated with hematoma formation within the two cohorts were tracked. Of 246 men who underwent penile prosthesis surgery, 194 (78.9%) patients underwent primary implantation and 52 (21.1%) were complex. Although hematoma formers in the complex group had comparable drain outputs to primary patients on postoperative day 0 (66.8cc ± 32.5 vs 48.4 ± 27.7, p = 0.470) and postoperative day 1 (40.3cc ± 20.8vs 21.8 ± 11.3 p = 0.125), hematomas in the complex group had a higher propensity for OR evacuation (p = 0.03). Difference in duration of temporary device inflation between 2 (64, 26%) and 4 weeks (182, 74%) did not contribute to hematoma formation (p = 0.562). The incidence of postoperative hematoma formation in complex cases was 9.6% (5/52) and 3.6% in primary cases (7/194) (HR = 2.61, p = 0.072). Complex IPP surgery performed for revision or with ancillary procedures are more likely to result in clinically significant hematomas that require surgical management, suggesting a need for heightened caution in managing these individuals.

Tissue adhesive hemostatic microneedle arrays for rapid hemorrhage treatment

Blood loss by hemorrhaging wounds accounts for over one-third of ∼5 million trauma fatalities worldwide every year. If not controlled in a timely manner, exsanguination can take lives within a few minutes. Developing new biomaterials that are easy to use by non-expert patients and promote rapid blood coagulation is an unmet medical need. Here, biocompatible, and biodegradable microneedle arrays (MNAs) based on gelatin methacryloyl (GelMA) biomaterial hybridized with silicate nanoplatelets (SNs) are developed for hemorrhage control. The SNs render the MNAs hemostatic, while the needle-shaped structure increases the contact area with blood, synergistically accelerating the clotting time from 11.5 min to 1.3 min in vitro. The engineered MNAs reduce bleeding by ∼92% compared with the untreated injury group in a rat liver bleeding model. SN-containing MNAs outperform the hemostatic effect of needle-free patches and a commercial hemostat in vivo via combining micro- and nanoengineered features. Furthermore, the tissue adhesive properties and mechanical interlocking support the suitability of MNAs for wound closure applications. These hemostatic MNAs may enable rapid hemorrhage control, particularly for patients in developing countries or remote areas with limited or no immediate access to hospitals.

Time-dependent effects of cellulose and gelatin-based hemostats on cellular processes of wound healing

INTRODUCTION

Oxidized regenerated cellulose-based (ORC - TABOTAMP), oxidized non-regenerated cellulose-based (ONRC - RESORBA CELL), and gelatin-based (GELA - GELITA TUFT-IT) hemostats are commonly used in surgery. However, their impact on the wound healing process remains largely unexplored. We here assess time-dependent effects of exposure to these hemostats on fibroblast-related wound healing processes.

MATERIAL AND METHODS

Hemostats were applied to fibroblast cell cultures for 5-10 (short-), 30 and 60 min (intermediate-) and 24 h (long-term). Representative images of the hemostat degradation process were obtained, and the pH value was measured. Cell viability, apoptosis and migration were analyzed after the above exposure times at 3, 6 and 24 h follow-up. Protein levels for tumor necrosis factor α (TNF-α) and transforming-growth factor β (TGF-β) were assessed.

RESULTS

ORC and ONRC reduced pH values during degradation, while GELA proved to be pH-neutral. Hemostat structural integrity was prolonged for GELA (vs. ORC and ONRC). TGF-β and TNF-α levels were reduced for ORC and ONRC (vs. GELA and control) (p < 0.05). Further, exposure of ORC and ONRC for longer than 5-10 min reduced cell viability vs. GELA and control at 3 h post-exposure (p < 0.05). Similarly, cell migration was impaired with ORC and ONRC exposure longer than 60 min at 24 h follow-up (p < 0.05).

CONCLUSIONS

Short-term exposure to ORC and ONRC impairs relevant wound healing-related processes in fibroblasts, and alters protein levels of key mediating cytokines. GELA does not show similar effects. We conclude that GELA may be preferred over ORC and ONRC over short-, intermediate- and long-term exposures. Future validation of the clinical relevance is warranted.

Gelatin-based hemostatic agents for medical and dental application at a glance: A narrative literature review

Uncontrolled bleeding is linked to higher treatment costs, risk of post-surgical infection and increased disease and death. Hemostatic agents are used to treat excessive bleeding. A good hemostatic agent controls bleeding effectively, reduces the need for blood transfusion, removes the need for systemic drugs to control bleeding, results in shorter surgery time, and reduces the cost and length of hospital stay of the patient. Gelatin-based hemostatic agents have been widely used in medical and dental procedures, owing to their biodegradability and biocompatibility, as well as availability and low cost of raw materials. In this narrative literature review, we discuss the background and different types of gelatin-based hemostatic agents in medical and dental procedures, the comparison of gelatin-based and non-gelatin-based hemostatic agents, and the usage and development of enhanced or novel gelatin-based hemostatic agents. Gelatin-based hemostatic agents are effective and important part of bleeding control, as evidenced by its wide application in medicine and dentistry. The development of novel combination gelatin-based hemostatic agents has much potential for effective control of excessive bleeding.

Bioabsorbable Carboxymethyl Starch-Calcium Ionic Assembly Powder as a Hemostatic Agent

In contrast to hemostatic fabrics, foams, and gels, hemostatic spray powders may be conveniently applied on narrow and complex bleeding sites. However, powdered hemostatic agents are easily desorbed from the bleeding surface because of blood flow, which seriously decreases their hemostatic function. In this study, the hemostatic performance of a bioabsorbable powder with decreased desorption was investigated. The proposed hemostatic powder (OOZFIXTM) is an ionic assembly of carboxymethyl starch and calcium. The microstructure and chemical properties of the hemostatic powder were analyzed. The hemostatic performance (blood absorption, blood absorption rate, and coagulation time), thromboelastography (TEG), rheology, adhesion force, and C3a complement activation of the OOZFIXTM were evaluated and compared with those of the carboxymethyl starch-based commercial hemostatic powder (AristaTM AH). The in vivo rat hepatic hemorrhage model for hemostasis time and bioabsorption of the OOZFIXTM showed quick biodegradation (<3 weeks) and a significantly improved hemostasis rate (78 ± 17 s) compared to that of AristaTM AH (182 ± 11) because of the reduced desorption. The bioabsorbable hemostatic powder OOZFIXTM is expected to be a promising hemostatic agent for precise medical surgical treatments.

Oxidized Regenerated Cellulose Mimicking a Retained Laparotomy Sponge

Oxidized regenerated cellulose (ORC) is an absorbable hemostat commonly used during gynecologic surgery. We present a case in which ORC was used in a patient undergoing posterior pelvic exenteration with ureteroneocystostomy for excision of a malignant pelvic mass. At the conclusion of these procedures, the laparotomy pad count was reported as incomplete likely due to the large number of laparotomy pads used and changes in nursing staff. Abdominal radiographs were obtained to verify no pads were retained in the abdominal cavity. These identified a poorly defined radiolucency deep in the patient's pelvis, requiring the surgical incision be reopened. Upon reexploration, no evidence of a retained surgical sponge could be identified. However, ORC was identified at the site of the radiolucency in question. Radiographs of this material, once removed, confirmed its radiolucent appearance. This experience clearly demonstrates that oxidized regenerated cellulose can mimic a retained surgical sponge on intraoperative radiographs. Dissemination of this knowledge will hopefully help to avoid radiographic misidentification of ORC in the perioperative window and minimizing the risk of unnecessary surgical interventions in the future.

Prevention of bleeding after percutaneous biopsy with a small intestinal submucosa hemostatic plug

Percutaneous biopsies (PBs) are the gold standard diagnostic procedures indicated for renal and hepatic disorders. Nevertheless, they can cause hemorrhages and are contraindicated for coagulopathic patients. In this study we designed, fabricated, and evaluated a small intestinal submucosa (SIS) plug to reduce, and potentially cease, bleeding to decrease death risk after percutaneous hepatic and renal biopsies in healthy and coagulopathic in vivo models. First, the plug's blocking capacity was determined with an increase in its diameter of 24 ± 11% after immersion in human blood, and the capacity to induce clotting on its surface. The plug's in vivo performance was evaluated in a healthy porcine model, which showed minimal inflammatory reaction without side effects confirmed by histological results after 30 days. The plug's response in the coagulopathic model was assessed using heparinized swine for 2 days, which revealed localized microhemorrhages and mild inflammatory response without any lesions to the surrounding tissue. No major adverse events nor macroscopic hemorrhages were detected in the animal models. Furthermore, we assessed the plug's efficacy to reduce and stop bleeding using a transplant-discarded human liver model (n = 14). In this case, the mass of blood lost was 43.8 ± 21.8% lower in plugged transplant-discarded human liver biopsies compared to control biopsies without a plug. The bleeding was stopped within three minutes in 92% of plugged cases, but only in 8% of non-plugged cases. We demonstrated the feasibility of making a hemostatic SIS plug, which does not induce major inflammatory reaction and can effectively reduce and stop bleeding after PBs in non-coagulopathic and coagulopathic in vivo models, and in a transplant-discarded human liver model. STATEMENT OF SIGNIFICANCE: Percutaneous biopsy (PB) is a gold standard diagnostic procedure, but it can provoke life-threatening complications and is contraindicated for patients with coagulopathic disorders. This study demonstrates that small intestinal submucosa (SIS) can be manufactured into a biocompatible thrombogenic plug, insertable through a commercial Tru-Cut needle sheath. This device takes advantage of the collagen-rich composition of SIS to stop and reduce bleeding more effectively than the traditional PB, indicating that it could be routinely employed in a traditional biopsy to increase safety, or as a cost and time-reducing alternative to transjugular biopsy for coagulopathic patients.

Polymeric Materials for Hemostatic Wound Healing

Hemorrhage is one of the greatest threats to life on the battlefield, accounting for 50% of total deaths. Nearly 86% of combat deaths occur within the first 30 min after wounding. While external wound injuries can be treated mostly using visual inspection, abdominal or internal hemorrhages are more challenging to treat with regular hemostatic dressings because of deep wounds and points of injury that cannot be located properly. The need to treat trauma wounds from limbs, abdomen, liver, stomach, colon, spleen, arterial, venous, and/or parenchymal hemorrhage accompanied by severe bleeding requires an immediate solution that the first responders can apply to reduce rapid exsanguinations from external wounds, including in military operations. This necessitates the development of a unique, easy-to-use, FDA-approved hemostatic treatment that can deliver the agent in less than 30 s and stop bleeding within the first 1 to 2 min at the point of injury without application of manual pressure on the wounded area.

Engineered Bio-inspired Multifunctional Peptide- and Protein-based Therapeutic Biomolecules for Better Wound Care

Developing non-immunogenic therapeutic biomolecules for facilitating blood clotting followed by wound healing via therapeutic angiogenesis, still remains a formidable challenge. Excessive blood loss of accident victims and battalions cause a huge number of deaths worldwide. Patients with inherited bleeding disorders face acute complications during injury and post-surgery. Biologically-inspired peptide-based hemostat can act as a potential therapeutic for handling coagulopathy. Additionally, non-healing wounds for patients having ischemic diseases can cause severe clinical complications. Advancement in stabilized growth-factor-based proangiogenic therapy may offer effective possibilities for the treatment of ischemic pathology. This review will discuss nature-inspired biocompatible stabilized peptide- and protein-based molecular medicines to serve unmet medical challenges for handling traumatic coagulopathy and impaired wound healing.

Hemostatic materials in wound care

Blood plays an essential role in the human body. Hemorrhage is a critical cause of both military and civilian casualties. The human body has its own hemostatic mechanism that involves complex processes and has limited capacity. However, in emergency situations such as battlefields and hospitals, when the hemostatic mechanism of the human body itself cannot stop bleeding effectively, hemostatic materials are needed for saving lives. In this review, the hemostatic mechanisms and performance of the most commonly used hemostatic materials, (including fibrin, collagen, zeolite, gelatin, alginate, chitosan, cellulose and cyanoacrylate) and the commercial wound dressings based on these materials, will be discussed. These materials may have limitations, such as poor tissue adhesion, risk of infection and exothermic reactions, that may lessen their hemostatic efficacy and cause secondary injuries. High-performance hemostatic materials, therefore, have been designed and developed to improve hemostatic efficiency in clinical use. In this review, hemostatic materials with advanced performances, such as antibacterial capacity, superhydrophobicity/superhydrophilicity, superelasticity, high porosity and/or biomimicry, will be introduced. Future prospects of hemostatic materials will also be discussed in this review.

Local Hemostatic Agents in Surgical Practice

At present, in emergency surgery, great importance is attached to reliable intraoperative hemostasis, for the achievement of which local hemostatic agents are used. The use of these funds tends to increase. The hemostatic agents are divided on 3 main groups. In turn, each group has its own physical and chemical characteristics and different ways of application. The surgeon have task of choosing and correctly using a specific hemostatic agent in a specific clinical situation, especially an emergency one. 

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.

Tissue Adhesives: From Research to Clinical Translation

Sutures, staples, clips and skin closure strips are used as the gold standard to close wounds after an injury. In spite of being the present standard of care, the utilization of these conventional methods is precarious amid complicated and sensitive surgeries such as vascular anastomosis, ocular surgeries, nerve repair, or due to the high-risk components included. Tissue adhesives function as an interface to connect the surfaces of wound edges and prevent them from separation. They are fluid or semi-fluid mixtures that can be easily used to seal any wound of any morphology - uniform or irregular. As such, they provide alternatives to new and novel platforms for wound closure methods. In this review, we offer a background on the improvement of distinctive tissue adhesives focusing on the chemistry of some of these products that have been a commercial success from the clinical application perspective. This review is aimed to provide a guide toward innovation of tissue bioadhesive materials and their associated biomedical applications.

Hemostatic strategies for uncontrolled bleeding: A comprehensive update

Uncontrolled bleeding remains the leading cause of morbidity and mortality across the entire macrocosm. It refers to excessive loss of blood that occurs inside of body, due to unsuccessful platelet plug formation at the injury site. It is not only limited to the battlefield, but remains the second leading cause of death amongst the civilians, as a result of traumatic injury. Startlingly, there are no effective treatments currently available, to cater the issue of internal bleeding, even though early intervention is of utmost significance in minimizing the mortality rates associated with it. The fatal issue of uncontrolled bleeding is ineffectively being dealt with the use of pressure dressings, tourniquet, and surgical procedures. This is not a practical approach in combat arenas or in emergency situations, where the traumatic injury inflicted is deep inside the body, and cannot be addressed externally, by the application of topical dressings. This review focuses on the traditional hemostatic agents that are used to augment the process of hemostasis, such as mineral zeolites, chitosan based products, biologically active agents, anti-fibrinolytics, absorbable agents, and albumin and glutaraldehyde, as well as the micro- and nano-based hemostatic agents such as synthocytes, thromboerythrocytes, thrombosomes, and the synthetic platelets.

Epidural hemostasis by autologous fat graft in minimally invasive surgery for lumbar spinal stenosis: In vivo experimental study

BACKGROUND

Epidural hemostasis needs to use small, adapted material in minimally invasive surgery, including bilateral decompression via a unilateral approach for lumbar spinal stenosis. Most surgeons avoid external material for hemostasis because of possible neural tissue damage or complications. We compared epidural hemostasis in minimally invasive surgery by fat graft versus gelatin sponge.

METHODS

The design was a prospective randomized controlled in-vivo human experimental study. The 24 levels operated on for lumbar spinal stenosis were evaluated in two groups: Group A (control group: gelatin sponge) and Group B (experimental group: fat graft). International Normalized Ratio and Prothrombin Time were assessed preoperatively. Number of cotton hemostats and systolic and diastolic blood pressure were assessed intraoperatively. Epidural hemorrhage area, spinal cord size and ratio of epidural hemorrhage area to spinal cord size were evaluated on early postoperative lumbar MRI.

RESULTS

Mean epidural hemorrhage area in groups A and B was respectively 1.3±0.5 and 1.2±0.6cm², and mean spinal cord size 1.2±0.6 and 1.8±0.6cm² on early postoperative axial lumbar MRI. The two groups did not significantly differ in ratio of epidural hemorrhage/spinal cord size or number of intraoperative hemostats (P=0.36, and P=0.71).

CONCLUSIONS

The autologous fat graft ensured sufficient and safe epidural hemostasis without serious adverse events in minimally invasive spinal surgery, and is preferable as autologous tissue is easily and quickly harvested. The surgeon feels safe with this technique and does not need external hemostatic agents.

Peptide-based topical agents and intravenous hemostat for rapid hemostasis

Traumatic coagulopathy due to severe external injury and internal hemorrhage is life-threatening to accident victims and soldiers on the battlefield, causing considerable number of deaths worldwide. Patients with inherited bleeding disorders (such as haemophilia, von Willebrand disease, inherited qualitative platelet defects, and afibrinogenemia) also contribute to the vast number of deaths due to abnormal bleeding, and these patients are difficult to handle during surgery. Platelets and different plasma proteins play an essential role in blood coagulation and in the maintenance of the body's hemostatic balance. The improper function or deficiency of these factors cause abnormal bleeding. To address such bleeding disorders, external clotting agents (such as extracellular protein-inspired natural and synthetic peptide-based sealants and peptide-functionalized polymer/liposome-based sealants) have been developed by different groups of researchers. The primary focus of this review is to provide molecular insights into the existing biologically inspired peptide-based sealants, highlighting the advantages and limitations of such reported designed sealants to handle blood clotting, and also provide insights into the design of improved next-generation surgical sealants.

Article Commentary: 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.

Use of hemostatic agents for surgical bleeding in laparoscopic partial nephrectomy: Biomaterials perspective

In recent years, there was an abrupt increase in the incidence of renal tumors, which prompt up the appearance of cutting-edge technology, including minimally invasive and organ-preserving approaches, such as laparoscopic partial nephrectomy (LPN). LPN is an innovative technique used to treat small renal masses that have been gaining popularity in the last few decades due to its promissory results. However, the bleeding control remains the main challenge since the majority of currently available hemostatic agents (HAs) used in other surgical specialities are inefficient in LPN. This hurried the search for effective HAs adapted for LPN surgical peculiarities, which resulted on the emergence of different types of topical HAs. The most promising are the natural origin HAs because of their inherent biodegradability, biocompatibility, and lowest toxicity. These properties turn them top interests' candidates as HAs in LPN. In this review, we present a deep overview on the progress achieved in the design of HAs based on natural origin polymers, highlighting their distinguishable characteristics and providing a clear understanding of their hemostat's role in LPN. This way it may be possible to establish a structure-composition properties relation, so that novel HAs for LPN can be designed to explore current unmet medical needs.

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.

An update on oxidized regenerated cellulose (fibrillar™) in reducing postoperative corporal bleeding following inflatable penile prosthesis surgery

Background

Scrotal hematoma formation is a dreaded complication of penile prosthesis surgery that increases patient pain and healthcare costs, as well the risk for eventual device infection and failure. The efficacy of hemostatic agents in reducing the incidence of scrotal hematoma development has not been extensively studied in urologic prosthetic surgery. In this paper we further evaluate our experience with oxidized regenerated cellulose (ORC; Surgicel Fibrillar™) as an adjunct to standard hemostatic practices in inflatable penile prosthesis (IPP) implantation.

Methods

From April 2016 onward, intracorporal ORC pledgets were placed during corporotomy closure in all patients undergoing IPP implantation or revision by a single surgeon using an identical surgical technique. Perioperative parameters and outcomes-primarily postoperative cumulative drain output, secondarily patient phone calls in the postoperative period-were compared among successive cases with ORC (April 2016 to February 2019) and without ORC (April 2013 to March 2016).

Results

A total of 274 men underwent IPP implantation during the study period; 175 (64%) had ORC included in their corporotomy closures. Median drain output was significantly reduced in the ORC patients relative to the non-ORC group (50 vs. 65 mL; P=0.0001). A significant reduction in patient-initiated phone calls regarding scrotal pain, swelling, or discomfort in the first 4 weeks following surgery was also observed in the ORC group (average 0.69 vs. 1.1 calls per patient; P=0.03). A total of 9 patients underwent IPP explantation during the study period, all due to device infection; 5 of these were in the ORC group, while 4 were in the non-ORC group (P=0.73). ORC use did not constitute any additional infection risk.

Conclusions

Bilateral incorporation of ORC pledgets during corporotomy closure in IPP surgery significantly decreases postoperative scrotal drain output, a well-documented risk factor for scrotal hematoma formation.

Endoscopic Therapy for Acute Diverticular Bleeding

Diverticular bleeding accounts for approximately 26%–40% of the cases of lower gastrointestinal bleeding. Rupture of the vasa recta at the neck or dome of the diverticula can be the cause of this bleeding. Colonoscopy aids in not only the diagnosis but also the treatment of diverticular bleeding after a steady bowel preparation. Endoscopic hemostasis involves several methods, such as injection/thermal contact therapy, clipping, endoscopic band ligation (EBL), hemostatic powder, and over-the-scope clips. Each endoscopic method can provide a secure initial hemostasis. With regard to the clinical outcomes after an endoscopic treatment, the methods reportedly have no significant differences in the initial hemostasis and early recurring bleeding; however, EBL might prevent the need for transcatheter arterial embolization or surgery. In contrast, the long-term outcomes of the endoscopic treatments, such as a late bleeding and recurrent bleeding at 1 and 2 years, are not well known for diverticular bleeding. With regard to a cure for diverticular bleeding, there should be an improvement in both the endoscopic methods and the multilateral perspectives, such as diet, medicines, interventional approaches, and surgery.

In vitro and in vivo evaluation of the duck's feet collagen sponge for hemostatic applications

Recently different hemostatic agents have been developed, but most of them are ineffective in severe bleeding and expensive or cause safety concerns. In this study, we fabricated duck's feet collagen-based porous sponges and investigated its use as a hemostatic agent. We determined the sponge's physical and biological characteristics and compared with Avitene via scanning electron microscope analysis, water-uptake abilities and porosity test, and cytotoxicity assay. The duck's feet collagen/silk sponge showed a larger interconnected porous structure compared to others sponges. The duck's feet collagen/silk sponge also exhibited significantly higher porosity than Avitene. Hemostatic properties of the sponges were evaluated by whole blood clotting and rat femoral artery hemorrhage experiment. The addition of silk to duck's feet collagen showed better blood clotting ability than Avitene in vitro. However, rat femoral artery hemorrhage test showed a similar hemostatic property between the duck's feet collagen-based sponges and Avitene. We suggest that duck's feet collagen-based sponge can be effectively used for hemostatic applications.

Agentes hemostáticos tópicos em cirurgia: revisão e perspectivas

RESUMO A hemostasia tem papel crítico e importância fundamental em todos os procedimentos cirúrgicos. Seu manejo possui diversos pontos chaves, que se iniciam por boa técnica operatória e adequado suporte anestésico. Determinadas situações, como hemorragias graves resultantes de trauma penetrante, por exemplo, não dependem exclusivamente do controle da equipe cirúrgica e necessitam do apoio de novas soluções que diminuam ou controlem a hemorragia. Desde os tempos antigos, um marco da medicina é atuar no controle da hemorragia e, mais recentemente, na facilitação da hemostasia pela aplicação de agentes tópicos, seja por compressão manual ou agentes modernos. Na última década, o número de diferentes agentes hemostáticos tópicos cresceu drasticamente. Para que o cirurgião moderno escolha o agente correto no momento correto, é essencial que conheça o mecanismo de ação, entenda a eficácia e os possíveis efeitos adversos relacionados a cada agente. Assim, a grande variedade de hemostáticos tópicos, somada à ausência de um artigo de revisão na literatura nacional sobre este tópico, nos estimulou a elaborar este manuscrito. Aqui relatamos uma revisão detalhada sobre os agentes hemostáticos tópicos mais comumente utilizados nas especialidades cirúrgicas.

Hemostatic Agents and Tissue Sealants: Potential Mimics of Abdominal Abnormalities

OBJECTIVE

Topical tissue sealants and hemostatic agents, seen on postoperative imaging in a variety of intraabdominal and pelvic locations, have the potential to be mistaken for abdominal abnormalities, especially if the radiologist is not aware of the patient's surgical history. The normal appearance of these agents may mimic abscesses, tumors, enlarged lymph nodes, or retained foreign bodies. Therefore, it is important to be familiar with their typical imaging appearances and to review the surgical records when needed to avoid misdiagnoses. The purpose of this article is to increase the radiologist's familiarity with various types of topical tissue sealants and hemostatic agents used during surgical and percutaneous procedures in the abdomen and pelvis along with their radiologic appearances.

CONCLUSION

Various types of hemostatic agents are now commonly used during surgery and percutaneous procedures in the abdomen and pelvis, and it is important to recognize the various appearances of these agents. Although there are suggestive features outlined in this article, the most important factor for the radiologist is to be aware of the patient's history and the possibility that a hemostatic agent may be present. On postoperative imaging, hemostatic agents may mimic abscesses, tumors, enlarged lymph nodes, or retained foreign bodies, and accurate diagnosis can save a patient unnecessary treatment. It is therefore crucial to incorporate knowledge of the patient's surgical history with recognition of the typical imaging appearances of hemostatic agents and other pseudolesions to avoid misdiagnoses.

Chitosan Pad, Cellulose Membrane, or Gelatin Sponge for Peridural Bleeding: An Efficacy Study on a Lumbar Laminectomized Rat Model

Study Design

Experimental study in an animal model.

Purpose

This study aims to evaluate the hemostatic properties of four common hemostatic materials including the chitosan clot pad, absorbable gelatin sponge, cellulose membrane, and gauze on peridural bleeding using a rat model.

Overview of Literature

Intraoperative bleeding during spinal surgery can lead to morbidities. Hemostatic materials have been developed, but the efficacy of these materials on peridural bleeding remains unclear.

Methods

Forty 8-week-old Sprague-Dawley rats were used in this study. Under adequate anesthesia, each rat was posteriorly dissected to their L5 and L6 spinous processes. Bleeding from muscles and soft tissue dissections was stopped before lumbar bone cutting. Immediately after the L5-L6 laminae were cut and removed, the rats were randomly allocated to receive one of the abovementioned hemostatic materials. All hemostatic materials were placed over the raw surface of cut bone and dura and changed every 60 seconds. The procedure was stopped when there was no further bleeding. Time to staunching and amount of bleeding were recorded for statistical analysis.

Results

The respective mean±standard deviation hemorrhage volume and time for the cellulose membrane, gelatin sponge, chitosan pad, and gauze were 1.19±0.44, 1.03±0.72, 0.96±0.57, and 1.98±0.62 mL, respectively, and 2.9±0.6, 2.1±0.6, 1.7±0.5, and 2.9±1.0 minutes, respectively. The overall bleeding volumes for the cellulose membrane, gelatin sponge, and chitosan pad were significantly lower than the overall bleeding volume for gauze.

Conclusions

Chitosan clot pads, gelatin sponges, and cellulose membranes have better hemostatic properties than gauze. The chitosan pad had the lowest average bleeding volume, followed by gelatin sponge and cellulose membrane.

Use of oxidized regenerated cellulose to achieve hemostasis during laparoscopic cholecystectomy: a retrospective cohort analysis

OBJECTIVE

Laparoscopic cholecystectomy is the first-choice treatment for symptomatic cholelithiasis. Though generally safe, this procedure is not without complications, with bleeding the most frequent cause of conversion to open cholecystectomy. Oxidized regenerated cellulose (ORC) added to conventional hemostatic strategies, is widely used to control bleeding during surgery despite limited evidence supporting its use. This retrospective study analyzed patients undergoing laparoscopic cholecystectomy in an Italian center over a 16-month period, between October 2014 and February 2016, who experienced uncontrollable bleeding despite the use of conventional hemostatic strategies, requiring the addition of ORC gauze (Emosist®).

RESULTS

Of the 530 patients who underwent laparoscopic cholecystectomy, 24 (4.5%) had uncontrollable bleeding from the liver bed. Of these, 62.5% had acute cholecystitis and 33.3% chronic cholecystitis; 1 patient was diagnosed with gallbladder carcinoma, postoperatively. Most patients had comorbidities, 16.7% had liver cirrhosis, and 37.5% used oral anticoagulants. The application of ORC rapidly controlled bleeding in all patients. Patients were discharged after a mean duration of 2.2 days. ORC was easy to use and well tolerated. Bleeding complications remain a relevant issue in laparoscopic cholecystectomy. ORC was able to promptly stop bleeding not adequately controlled by conventional methods and appears, therefore, to be a useful hemostat.

Apprising the diverse facets of Platelet rich fibrin in surgery through a systematic review

CONTEXT

Comprehensive reviews on clinical applications of Platelet rich fibrin (PRF) in surgery are limited despite its extensive utilization resulting in a dearth of knowledge on its effectiveness. Hence this article focuses on shedding light to the various applications of PRF pertaining to surgery through a systematic review.

OBJECTIVE

The systematic review is aimed at evaluating the value of PRF in different areas of surgery.

DATA SOURCES

A systematic review of articles sourced from MEDLINE-pubmed (2008-2017(July)) was done. Additional articles were searched through GOOGLE SCHOLAR and SCIENCE DIRECT. Search terms such as Platelet rich fibrin; Platelet rich fibrin, surgery; Platelet concentrate; second generation concentrate; Applications of PRF in surgery were used.

STUDY SELECTION

Systematic reviews, Randomized control trials, Pilot studies and Case reports were included. Non English articles, in-vitro and animal studies were excluded.

DATA EXTRACTION

Independent sourcing of articles by 3 authors using a set of predefined criteria.

DATA SYNTHESIS

Out of the 25 articles covering various surgical procedures that met the inclusion criteria, positive outcomes were noted in most. Although categorization into one specific type of study was not done, the overall success rate with PRF usage was 78%.No differences between test and control groups were observed in 2 studies and 3 studies showed no significant improvements with the usage of PRF.

LIMITATIONS

The systematic review did not categorize the study designs while evaluating success rates which might be considered as a shortcoming as case reports were also included.

CONCLUSIONS

The future propositions are vast and point towards innovative applications of this bio-material possibly in transplant and burn cases if a method of obtaining large amounts can be devised. However since we rely on evidence-based results, further long term studies are needed in distinct areas of applications to decisively prove its effectiveness.

Oxidized Regenerated Cellulose (Fibrillar) Reduces Risk of Postoperative Corporal Bleeding Following Inflatable Penile Prosthesis Surgery

OBJECTIVE

To report our initial experience with oxidized regenerated cellulose (ORC; Surgicel Fibrillar) as a hemostatic adjunct during inflatable penile prosthesis (IPP) surgery.

MATERIALS AND METHODS

Beginning in April 2016, ORC pledgets were placed within the corporotomy closures of all men undergoing IPP insertion. Perioperative characteristics and outcomes including cumulative postoperative drain output were evaluated among consecutive cases with (April 2016 to October 2016) and without ORC (December 2015 to March 2016) using an identical surgical technique by a single surgeon.

RESULTS

During the study period, 64 men underwent IPP implantation, of whom 32 (50%) received ORC. There was a significant reduction in median drain output relative to controls (33 mL vs 65 mL; P = .01). Postoperatively, ORC use was associated with a reduction in the number of patient phone calls for scrotal-related concerns in the immediate postoperative period (average 0.5 vs 1.1; P = .03). There were 3 IPP explantations in the non-ORC group (2/3 for infection)-one of which was directly related to an infected hematoma. After controlling for other clinical features, the use of ORC (β -32, 95% confidence interval: -61 to -5; P = .02) was independently associated with a reduction in drain output.

CONCLUSION

ORC use during IPP corporotomy closure reduces postoperative drain output, a known risk factor for hematoma-related complications.

The Physiological Incubation Biosimulator (PIBS): An Improved Ex Vivo Experimental Setup for the Mechanical Stability of Biological Sealants in Surgical Procedures

BACKGROUND

Tissue-bound fibrin sealants are used in a wide array of surgical procedures. The microenvironmental interaction between sealant and application site is often poorly evaluated due to a lack of suitable experimental models.

METHODS

A physiological incubation biosimulator (PIBS) was developed to test biological sealants in an ex vivo setup under physiological conditions comparable to the microenvironment at application site (temperature, humidity, pressure). PIBS was validated by a study on the effectiveness of TachoSil for leak closure at pancreatic resection sites. Defined defects in a thoracic membrane of porcine origin were sealed by TachoSil. Integrity of the sealing was tested in the presence of active pancreatic fluid over 60 minutes. Heat-inactivated pancreatic fluid and electrolyte solution served as controls. The time to leakage was recorded and experimental groups were analyzed by Kaplan-Meier analysis.

RESULTS

PIBS produced reliable results. TachoSil lead to a leakage rate of 96% after incubation with active pancreatic fluid (p = 34), which was significantly higher compared with heat-inactivated pancreatic fluid (p = 34, 52%) or electrolyte solution (p = 20, 19%).

CONCLUSION

PIBS is an effective tool to evaluate microenvironmental effects on the adhesive strength of biomaterials. Tissue sealing effect of TachoSil is diminished in a "pancreatic" microenvironment rich with pancreatic enzymes. Our results might therefore explain the reason of the findings of randomized controlled trials recently published on this subject.

A randomized controlled trial on effects of different hemostatic sponges in posterior spinal fusion surgeries

Background

Spinal fusion surgery is associated with significant blood loss, which may result in potential clinical complications, it is necessary to take safe and effective measures to reduce blood loss in surgery. We perform this study to assess the impact of three different hemostatic materials on perioperative blood loss.

Methods

We performed a Randomized Controlled Trial research and recruited patients with lumbar disease into the study between November 2013 and March 2015. All the participants were randomly assigned to 3 groups using a simple equal probability randomization scheme: Group A (Stypro hemostatic sponge), Group B (Collagen hemostatic sponge) and Group C (gelatin sponge). We compared postoperative blood loss between these 3 groups.

Results

In our study, drainage volume in the first 24 h of patients in Group A and B is significantly smaller, as well as total postoperative volumes of drainage (p < 0.05) during their hospital stay. The drainage volumes in the second 24 h were similar in the 3 groups. We also found that the average drainage Hematocrit (HCT) reduced over time, the average HCT of drainage is 18.04% and 11.72% on the first day and on the second day respectively.

Conclusions

Hemostatic collagen sponge demonstrated better hemostasis effects than gelatin sponge with lower volume of postoperative drainage volume and blood loss in posterior spinal fusion surgery.

Trial registration

The trial registration number (TRN) of the study is ISRCTN29254316 and date of registration is 25/10/2016. Our trial was registered retrospectively.

Collagen–carboxymethyl cellulose–tricalcium phosphate multi-lamellar cryogels for tissue engineering applications: Production and characterization

Collagen–carboxymethyl cellulose–tricalcium phosphate cryogels were prepared for diverse biomedical applications. Further chemical and structural characterizations were performed by Fourier transform infrared spectra, thermogravimetric analysis, X-ray crystallography, and scanning electron microscopy. The mechanical properties were tested by unconfined compression test. Moreover, hemocompatibility of the cryogels was also evaluated by basic biochemical blood testing. Chemical and structural analysis results demonstrate the achievement of the cross-linking without any major alteration in collagen and carboxymethyl cellulose with a thermally and structurally stable blend formation. Scanning electron micrographs demonstrate the multi-lamellar formation with macro- and micro-pore compositions which can correlate with water uptake results of the cryogels. Hemocompatibility evaluations exhibited that the cryogels are non-toxic and blood-compatible. The overall results including mechanical testing of these tricalcium phosphate–consisting collagen/carboxymethyl cellulose cryogels may have potential use as a material for hard tissue regeneration.

Observed outcomes on the use of oxidized and regenerated cellulose polymer for breast conserving surgery - A case series

BACKGROUND

Oxidized regenerated cellulose polymer (ORCP) may be used for reshaping and filling lack of volume in breast-conserving surgery (BCS). The study aimed to observe both the aesthetic and diagnostic outcomes in patients with different age, BMI, breast volume, and breast tissue composition over 36 months after BCS with ORCP.

PATIENTS AND METHODS

18 patients with early breast cancer and with proliferative benign lesions underwent BCS with ORCP that was layered in three-dimensional wafer, and placed into the Chassaignac space between the mammary gland and the fascia of pectoralis major with no fixation. After surgery, patients started a clinical and instrumental 36-month follow-up with mammography, ultrasonography, magnetic resonance imaging (MRI) and cytological examination with fine needle aspiration when seroma occurred.

RESULTS

Below the median age of 66 years old no complications were observed even in case both of overweight, and large breasts with low density. Over the median age seromas occurred with either small or large skin retraction, with the exception of 1 patient having quite dense breasts and low BMI, which had no complications. In elderly patients, 1 case with quite dense breasts and high BMI showed severe seroma and skin retraction, while 1 case with low BMI and less dense breasts highlighted milder complications.

CONCLUSION

During 36 months after BCS with ORCP, a significant correlation between positive diagnostic and aesthetic outcomes and low age, dense breasts, and low BMI of patient was observed. Despite of the few number of cases, either low BMI, or high breast density improved the aesthetic outcomes and reduced the entity of complications even in the elderly patients.

Variation in hospital resource use and cost among surgical procedures using topical absorbable hemostats

Background

Adjunctive hemostats are used to assist with the control of intraoperative bleeding. The most common types are flowables, gelatins, thrombins, and oxidized regenerated celluloses (ORCs). In the US, Surgicel^® products are the only US Food and Drug Administration-approved ORCs.

Objective

To compare the outcomes of health care resource utilization (HRU) and costs associated with using ORCs compared to other adjunctive hemostats (OAHs are defined as flowables, gelatins, and topical thrombins) for surgical procedures in the US inpatient setting.

Patients and methods

A retrospective, US-based cohort study was conducted using hospital inpatient discharges from the 2011–2012 calendar years in the Premier Healthcare Database. Patients with either an ORC or an OAH who underwent a cardiovascular procedure (valve surgery and/or coronary artery bypass graft surgery), carotid endarterectomy, cholecystectomy, or hysterectomy were included. Propensity score matching was used to create comparable groups of ORC and OAH patients. Clinical, economic, and HRU outcomes were compared.

Results

The propensity score matching created balanced patient cohorts for cardiovascular procedure (22,718 patients), carotid endarterectomy (10,890 patients), cholecystectomy (6,090 patients), and hysterectomy (9,348 patients). In all procedures, hemostatic agent costs were 28%–56% lower for ORCs, and mean hemostat units per discharge were 16%–41% lower for ORCs compared to OAHs. Length of stay and total procedure costs for patients treated with ORCs were lower for carotid endarterectomy patients (0.3 days and US$700) and for cholecystectomy patients (1 day and US$3,350) (all P<0.001).

Conclusion

Costs and HRU for patients treated with ORCs were lower than or similar to patients treated with OAHs. Proper selection of the appropriate hemostatic agents has the potential to influence clinical outcomes and treatment costs.

Computer aided biomanufacturing of mechanically robust pure collagen meshes with controlled macroporosity

Reconciliation of high strength and high porosity in pure collagen based structures is a major barrier in collagen's use in load-bearing applications. The current study developed a CAD/CAM based electrocompaction method to manufacture highly porous patterned scaffolds using pure collagen. Utilization of computerized scaffold design and fabrication allows the integration of mesh-scaffolds with controlled pore size, shape and spacing. Mechanical properties of fabricated collagen meshes were investigated as a function of number of patterned layers, and with different pore geometries. The tensile stiffness, tensile strength and modulus ranges from 10-50 N cm(-1), 1-6 MPa and 5-40 MPa respectively for all the scaffold groups. These results are within the range of practical usability of different tissue engineering application such as tendon, hernia, stress urinary incontinence or thoracic wall reconstruction. Moreover, 3-fold increase in the layer number resulted in more than 5-fold increases in failure load, toughness and stiffness which suggests that by changing the number of layers and shape of the structure, mechanical properties can be modulated for the aforementioned tissue engineering application. These patterned scaffolds offer a porosity ranging from 0.8 to 1.5 mm in size, a range that is commensurate with pore sizes of repair meshes in the market. The connected macroporosity of the scaffolds facilitated cell-seeding such that cells populated the entire scaffold at the time of seeding. After 3 d of culture, cell nuclei became elongated. These results indicate that the patterned electrochemical deposition method in this study was able to develop mechanically robust, highly porous collagen scaffolds with controlled porosity which not only tries to solve one of the major tissue engineering problems at a fundamental level but also has a significant potential to be used in different tissue engineering applications.

Hemostatic Powders in Gastrointestinal Bleeding: A Systematic Review

Topical hemostatic agents and powders are an emerging modality in the endoscopic management of upper and lower gastrointestinal bleeding. This systematic review demonstrates the effectiveness and safety of these agents with special emphasis on TC-325 and Ankaferd Blood Stopper. The unique noncontact/nontraumatic application, ability to cover large areas of bleed, and ease of use make these hemostatic agents an attractive option in certain clinical situations, such as massive bleeding with poor visualization, salvage therapy, and diffuse bleeding from luminal malignancies.

Fatal intraoperative cardiac arrest after application of surgifoam into a bleeding iliac screw defect

STUDY DESIGN

Case report.

OBJECTIVE

To describe the presentation, management, and autopsy findings in a case of a fatal intraoperative cardiac arrest after application of an absorbable hemostatic agent into a bleeding iliac bone screw defect.

SUMMARY OF BACKGROUND DATA

To the authors' knowledge, this represents the first reported complication of intraoperative death associated with Surgifoam (Ethicon) thromboembolization to the heart and lung microcirculation after its application into a bleeding bone defect.

METHODS

A 56-year-old male was undergoing revision fusion surgery for pseudarthrosis after multilevel thoracolumbosacral fusion with pelvic fixation for degenerative scoliosis. Intraoperatively, upon removal of the right iliac screw, heavy venous bleeding was encountered, which was stopped after application of 10 mL of Surgifoam into the screw defect. Approximately 5 minutes later, the patient's end tidal CO2 dropped, and his pulse was lost. Epinephrine was administered and the patient was immediately turned to supine position and cardiopulmonary resuscitation initiated. Cardiopulmonary resuscitation was performed unsuccessfully for 30 minutes at the end of which the patient was pronounced dead.

RESULTS

Autopsy findings revealed angulated particles of hemostatic agent with entrapped red blood cells partially to completely occluding small-to-medium-sized vessels of the heart and lungs. The cause of death was pulmonary and cardiac embolization of foreign material from the surgical screw defect to the vessels of the heart and lungs, significantly compromising respiration and blood flow causing sudden death.

CONCLUSION

Although Surgifoam is an excellent hemostatic agent for use in spinal surgery, it must be used with extreme caution in the setting of heavily bleeding bone defects after pedicle cannulation or removal of instrumentation. In cases when brisk venous bleeding is encountered, signifying potential compromise of an emissary vein, use of other hemostatic agents such as bone wax may be a safer option.

LEVEL OF EVIDENCE

N/A.

Economic and outcomes consequences of TachoSil®: a systematic review

BACKGROUND

TachoSil(®) is a medicated sponge coated with human fibrinogen and human thrombin. It is indicated as a support treatment in adult surgery to improve hemostasis, promote tissue sealing, and support sutures when standard surgical techniques are insufficient. This review systematically analyses the international scientific literature relating to the use of TachoSil in hemostasis and as a surgical sealant, from the point of view of its economic impact.

METHODS

We carried out a systematic review of the PubMed literature up to November 2013. Based on the selection criteria, papers were grouped according to the following outcomes: reduction of time to hemostasis; decrease in length of hospital stay; and decrease in postoperative complications.

RESULTS

Twenty-four scientific papers were screened, 13 (54%) of which were randomized controlled trials and included a total of 2,116 patients, 1,055 of whom were treated with TachoSil. In the clinical studies carried out in patients undergoing hepatic, cardiac, or renal surgery, the time to hemostasis obtained with TachoSil was lower (1-4 minutes) than the time measured with other techniques and hemostatic drugs, with statistically significant differences. Moreover, in 13 of 15 studies, TachoSil showed a statistically significant reduction in postoperative complications in comparison with the standard surgical procedure. The range of the observed decrease in the length of hospital stay for TachoSil patients was 2.01-3.58 days versus standard techniques, with a statistically significant difference in favor of TachoSil in eight of 15 studies.

CONCLUSION

This analysis shows that TachoSil has a role as a supportive treatment in surgery to improve hemostasis and promote tissue sealing when standard techniques are insufficient, with a consequent decrease in postoperative complications and hospital costs.