A comprehensive review of topical hemostatic agents: The good, the bad, and the novel

Safety and effectiveness of Merizelle oxidised regenerated cellulose in achieving haemostasis in surgical procedures: a surveillance study

OBJECTIVE

Topical haemostatic materials applied to bleeding sites during surgery play an important role in intraoperative haemostasis. This study aimed to evaluate the clinical safety and efficacy of Merizelle oxidised regenerated cellulose (ORC) (Meril Life Sciences Pvt. Ltd., India) in achieving haemostasis across various surgical procedures.

METHOD

This was a prospective, multicentre, single-arm, observational, post-marketing surveillance study. The primary endpoint was the proportion of patients achieving haemostasis within 10 minutes of application of ORC at target bleeding sites. The secondary endpoints were the absence of proven infection and the absence of bleeding-related adverse events (AEs) until six months after surgery. Patients were followed up at discharge, two weeks, one month, three months and six months after the index procedure.

RESULTS

In all, 189 patients were screened and enrolled, and 188 patients completed the study. The mean±standard deviation (SD) age of patients was 43.00±12.79 years and 59.79% were female. Neurological surgeries, nephrectomy and lower segment caesarean section were the most common surgeries performed. The mean±SD length of hospital stay was 6.28±4.08 days and the mean±SD coagulation time was 2.57±1.12 minutes. Haemostasis was achieved in all patients with the use of Merizelle ORC, with 94.68% of patients achieving it within 10 minutes. Almost 80% of patients had mild-to-moderate bleeding. There were no cases of bleeding-related AEs, proven infection or death at the end of all follow-ups.

CONCLUSION

The ORC demonstrated excellent safety with no occurrence of bleeding-related AEs, proven infections or postoperative death.

Tuning chitosan properties to enhance blood coagulation

The search for new hemostatic materials remains a priority for researchers, as the problem of uncontrolled hemorrhage during surgical interventions or traumatic injuries represents a significant challenge. The objective of the study was to identify novel polysaccharide structures with enhanced hemostatic properties based on chitosan. The number of chitosan derivatives with two substituents was synthesized and characterized by 1H NMR, FTIR. One of these was a structural analogue of L-DOPA - N-(3,4-dihydroxybenzyl), while the other comprised fragments of different nature, including hydrophobic N-(4-(tetradecyloxy)benzyl), negatively charged groups N-(4-carboxybenzyl) and aminocaproic acid residue. The hemostatic potential of the novel compounds was evaluated in vitro/in vivo on human blood and in mouse model of tail bleeding. Solutions of chitosan derivatives showed the ability to aggregate with blood about 3-5 times higher than chitosan in a neutral saline medium (0.9 % NaCl) and slightly acidic conditions both when (Ca2+) was added and in the case of citrated blood. Chitosan derivatives demonstrated low toxicity (3T3, HepG2 and Huh7) and did not induce plasma coagulation or platelet aggregation at low concentrations. The novel compounds can be used to modify the surface of biomaterials in order to improve their hemostatic properties.

Bottom-up reconstitution design of a biomimetic atelocollagen microfibril for enhancing hemostatic, antibacterial, and biodegradable benefits

Powdered collagen is emerging as a promising topical hemostat owing to its adaptability to various wounds, active hemostatic abilities, and biosafety. The reproduction of a bionic structure similar to natural collagen is crucial for effective hemostasis and bioactivity. Additional factors relevant to clinical application include antimicrobial properties, minimal immune response, and straightforward preparation. However, current developments in collagen hemostatic powders often lack comprehensive integration of these multidimensional attributes. In this study, atelocollagen molecules and antimicrobial peptide (ε-polylysine) were successfully employed to achieve the simultaneous expression of biomimetic structures and antimicrobial functions through a bottom-up reconstruction design. The synergistic effects of low temperature and mechanical processing facilitated the dispersion of collagen fibrils without leading to a stiffened network. The resultant atelocollagen microfibril (BCF-10) exhibited biomimetic D-periodicity and a fluffy morphology. BCF-10 demonstrated excellent antimicrobial properties and biocompatibility. Notably, BCF-10 could absorb blood up to 12 times its own weight within 15 s and significantly activate platelets to promote coagulation. In both a rat tail amputation model and a liver multi-point puncture model, BCF-10 exhibited significantly improved hemostatic capability compared to commercially available gauze (****P < 0.0001) and was found to be comparable to the well-established microfibrillar collagen hemostat, Avitene. Immune response assessments indicated that BCF-10 could be biodegraded within 30 days without eliciting a severe inflammatory response, and could serve as a scaffold for cellular infiltration to promote tissue regeneration. This research presents a straightforward and effective strategy for preparing a biomimetic atelocollagen microfibril that is efficient in hemostasis, infection prevention, and rapid biodegradability, positioning BCF-10 as a promising candidate for clinical translation and application.

Development of a 50% (w/v) aluminium chloride hexahydrate solution as haemostatic agent

OBJECTIVES

Acceleration of the haemostasis process after dermatological surgery predominantly relies on mechanical methods, such as the use of sutures or staples. To our knowledge, there is currently no commercialised haemostatic agent for this specific application. Due to the protein precipitation properties of the 50% (w/v) aluminium chloride hexahydrate solution, its physicochemical stability and maintenance of sterility over a 6 month period were assessed.

METHODS

Aluminium chloride hexahydrate was dissolved in sterile water to obtain a 50% (w/v) solution, which was subsequently sterilised through filtration. The solution was then placed in brown glass vials and kept at 20-25°C. The physicochemical stability and sterility of the solution were assessed at four different time points (D0, M1, M3 and M6). At each time point, pH and osmolality were measured, the chloride concentration of the sample was evaluated using the Mohr method, and aluminium identification was carried out through a precipitation method. In addition, the sterility of the solution was also assessed at each time point, according to the European Pharmacopoeia method.

RESULTS

The pH, osmolality and chloride concentration values remained stable and were concordant with the expected values throughout the study. Aluminium was identified in each sample. The sterility of the solution was maintained over the study period.

CONCLUSIONS

The physicochemical stability and sterility of the 50% (w/v) aluminium chloride hexahydrate solution were maintained for 6 months. These results indicate that the solution can be prepared in advance.

Comparative analyses of the hemostatic efficacy and surgical device performance of powdered oxidized regenerated cellulose and starch-based powder formulations

Background

Hemostatic powders offer unique therapeutic advantages over other formulations, including ease of application and rapid distribution over large bleeding surfaces. The efficacy of powder-based hemostats is dependent on device performance, which is rarely investigated independently from efficacy.

Objectives

The current study aimed to compare the hemostatic efficacy of an oxidized regenerated cellulose agent (Surgicel, Ethicon, Inc) and 3 starch-based biopolymers (Arista, Becton Dickinson; PerClot, Baxter International; and 4DryField, PlantTec Medical GmbH) and the performance of their delivery device applicators.

Methods

Efficacy was evaluated in a porcine model of bleeding using 2 study designs where the powder was delivered with (experiment 1) and without (experiment 2) device applicators. Device performance (powder expression) was examined in vitro at 3 device positions/angles: 90° (vertical, downward), 45° (slanted, downward), and 180° (horizontal).

Results

Surgicel efficacy rate was noninferior (P ≤ .0002) and superior (P ≤ .004) to that of any of the 3 starch-based agents regardless of whether the powder was delivered with their devices (experiment 1) or directly applied onto the bleeding sites (experiment 2). Surgicel required fewer applications (P ≤ .0002) and less powder (P < .0001) to achieve hemostasis. The Surgicel device was the only one that consistently delivered precise amounts of powder over a critical range of applications in the 3 positions tested.

Conclusion

The oxidized regenerated cellulose powder was the most efficacious hemostat, and the Surgicel applicator exhibited the highest performance compared with any of the 3 starch-based devices investigated. The current study highlights the relevance of combining high-efficacy powder hemostats with innovative, high-performance applicators to effectively manage bleeding control in surgical settings.

A Study of Safety and Effectiveness of Evicel Fibrin Sealant as an Adjunctive Hemostat in Pediatric Surgery

INTRODUCTION

 Data on the use of fibrin sealants to control intraoperative bleeding in children are scarce. Evicel Fibrin Sealant (Ethicon Inc., Raritan, New Jersey, United States) was found safe and effective in clinical trials of adults undergoing various surgery types. We evaluated the safety and efficacy of Evicel versus Surgicel Absorbable Hemostat (Ethicon Inc.) as adjunctive topical hemostats for mild/moderate raw-surface bleeding in pediatric surgery.

METHODS

 A phase III randomized clinical trial was designed as required by the European Medicines Agency's Evicel Pediatric Investigation Plan: 40 pediatric subjects undergoing abdominal, retroperitoneal, pelvic, or thoracic surgery were randomized to Evicel or Surgicel, to treat intraoperative mild-to-moderate bleeding. Descriptive analyses included time-to-hemostasis and rates of treatment success (4, 7, 10 minutes), intraoperative treatment failure, rebleeding, and thromboembolic events.

RESULTS

 Forty of 130 screened subjects aged 0.9 to 17 years were randomized 1:1 to Evicel or Surgicel. Surgeries were predominantly open abdominal procedures. The median bleeding area was 4.0 cm2 for Evicel and 1.0 cm2 for Surgicel. The median time-to-hemostasis was 4.0 minutes for both groups. The 4-, 7-, and 10-minute treatment success rates were 80.0% versus 65.0%, 100.0% versus 80.0%, and 95.0% versus 90.0%, whereas treatment failure rates were 5.0% versus 25.0%, for Evicel and Surgicel, respectively. No deaths or thrombotic events occurred. Re-bleeding occurred in 5.0% of Evicel and 10.0% of Surgicel subjects.

CONCLUSIONS

 In accordance with adult clinical trials, this randomized study supports the safety and efficacy of Evicel for controlling mild-to-moderate surgical bleeding in a broad range of pediatric surgical procedures.

Potential novel role of the human amniotic membrane as a sustainable hemostat

OBJECTIVES

Acute hemorrhage can cause significant morbidity and mortality arising from trauma, bleeding disorders, surgical procedures, or obstetric complications. Surgical hemostasis methods may fail to stop acute bleeding due to the complex bleeding dynamics of each bleeding type. Therefore, developing safe and effective topical hemostatic agents remains crucial. The human amniotic membrane (hAM) has established clinical evidence of effectiveness in promoting wound healing and tissue regeneration. Despite its unique biological and immunologic properties and its structural composition of established hemostatic elements, the hemostatic role of hAM has not been yet explored. The present study aimed to investigate this potential role and to describe the development protocol and characterization of hAM-derived topical hemostat.

METHODS

Surface electron microscope (SEM) imaging and Fourier transform infrared (FTIR) spectroscopy were used for characterization, and mouse models with induced peritoneal and tail wound bleeding were employed to evaluate the hemostatic effectiveness using physiological studies, in comparison to a chitosan-based combat-scale hemostat.

RESULTS

The hAM hemostat showed a distinctive composition by SEM and FTIR. Applying equal masses of the hAM hemostat, the commercial hemostat, or a combination reduced peritoneal wound bleeding time to averages of 108.4, 86.2, and 76.8 s, respectively, compared to the control group (300 s). Tail wound bleeding times were similarly reduced with no significant difference between the hAM and the commercial hemostat (P values = 0.29, 0.34 in peritoneal and tail wounds, respectively). Neither hemostat affected coagulation time.

CONCLUSION

This study describes a simple cost-effective preparation protocol for a hAM-based hemostatic agent. The long-recognized safety, sustainability, and immunotolerance advantages of hAM can establish superiority over commercial hemostats with reported safety concerns. Robust research validation in larger-scale bleeding models is required for wider applications and severe bleeding types.

Pregelatinized hydroxypropyl distarch phosphate-reinforced calcium sulfate bone cement for bleeding bone treatment

Considering the shortcomings of known medical hemostatic materials such as bone wax for bleeding bone management, it is essential to develop alternative bone materials capable of efficient hemostasis and bone regeneration and adaptable to clinical surgical needs. Thus, in the current work, a calcium sulfate hemihydrate and starch-based composite paste was developed and optimized. Firstly, it was found that the use of hydroxypropyl distarch phosphate (HDP) coupled with pregelatinization could generate an injectable, malleable and self-hardening paste with impressive anti-collapse ability in a dynamic aqueous environment, suggesting its potential applicability in both open and minimally invasive clinical practice. The as-hardened matrix exhibited a compressive strength of up to 61.68 ± 5.13 MPa compared to calcium sulfate cement with a compressive strength of 15.16 ± 2.42 MPa, making it a promising candidate for the temporary mechanical stabilization of bone defects. Secondly, the as-prepared paste revealed superior hemostasis and bone regenerative capabilities compared to calcium sulfate cement and bone wax, with greatly enhanced bleeding management and bone healing outcomes when subjected to testing in in vitro and in vivo models. In summary, our results confirmed that calcium sulfate bone cement reinforced with the selected starch can act as a reliable platform for bleeding bone treatment, overcoming the limitations of traditional bone hemostatic agents.

Review of Evidence Supporting the Arista™ Absorbable Powder Hemostat

Background

Uncontrolled and diffuse bleeding is a dreaded event during open and laparoscopic surgery that may lead to postoperative complications, obstruction of the surgical field that reduces visualization, and prolonged operating times. Powder hemostats can be used to control bleeding and are easy to use, have a safe profile, and can achieve broad coverage area at a low cost.

Methods

A strategic literature search of peer-reviewed, English language studies was conducted to capture evidence on the clinical efficacy and safety of a Microporous Polysaccharide Hemosphere (MPH) based Hemostat (Arista™ Absorbable Hemostat (Arista™ AH)).

Results

Six preclinical studies were found which supported the use of MPH in various animal models of laparoscopic and open surgery, all of which demonstrated its safety and efficacy. Five single-arm and 11 comparative clinical studies similarly supported the efficacy and safety of MPH in various surgery types, including cardiac, renal, and dermatologic surgery.

Conclusion

Published evidence supports the safe and effective use of MPH across a variety of surgical settings.

Prediction model for haematoma after tissue expander placement: A retrospective cohort study of 7080 cases over 20 years

Haematoma is an early complication of tissue expander placement and can lead to infection, capsule contracture and various complications, hindering successful reconstruction. However, no scientific models can accurately predict the risk of haematoma following tissue expansion. Therefore, this study aimed to develop and validate a prediction model for haematoma following tissue expander placement. The medical records of patients who underwent expander placement between 2001 and 2021 were obtained from the clinical database of the Department of Plastic Surgery at the Xijing Hospital. A total of 4579 consecutive patients with 7080 expanders and 179 expanded pocket haematomas were analysed. Multivariate logistic regression analysis identified adult age (P = 0.006), male sex (P < 0.001), scar reconstruction (P = 0.019), perioperative hypertension (P < 0.001), face and neck location (P = 0.002) and activated partial thromboplastin time above the normal range (P < 0.001) as risk factors for haematoma. Therefore, these were included in the prediction model, and a nomogram was constructed. The discrimination of the nomogram was robust (area under the curve: 0.78; 95% confidence interval: 0.72-0.83). Further, the prediction model had a strong fit (Hosmer-Lemeshow test, P = 0.066) and maintained similar discrimination after considering performance optimism (bootstrapped area under the curve: 0.79; 95% confidence interval: 0.73-0.84). This clinical prediction model was created using a generalisable dataset and can be utilised to obtain valid haematoma predictions after expander placement, assisting surgeons in implementing preventive measures or interventions to reduce the occurrence of haematoma.

Electrospun organic/inorganic hybrid nanofibers for accelerating wound healing: a review

Electrospun nanofiber membranes hold great promise as scaffolds for tissue reconstruction, mirroring the natural extracellular matrix (ECM) in their structure. However, their limited bioactive functions have hindered their effectiveness in fostering wound healing. Inorganic nanoparticles possess commendable biocompatibility, which can expedite wound healing; nevertheless, deploying them in the particle form presents challenges associated with removal or collection. To capitalize on the strengths of both components, electrospun organic/inorganic hybrid nanofibers (HNFs) have emerged as a groundbreaking solution for accelerating wound healing and maintaining stability throughout the healing process. In this review, we provide an overview of recent advancements in the utilization of HNFs for wound treatment. The review begins by elucidating various fabrication methods for hybrid nanofibers, encompassing direct electrospinning, coaxial electrospinning, and electrospinning with subsequent loading. These techniques facilitate the construction of micro-nano structures and the controlled release of inorganic ions. Subsequently, we delve into the manifold applications of HNFs in promoting the wound regeneration process. These applications encompass hemostasis, antibacterial properties, anti-inflammatory effects, stimulation of cell proliferation, and facilitation of angiogenesis. Finally, we offer insights into the prospective trends in the utilization of hybrid nanofiber-based wound dressings, charting the path forward in this dynamic field of research.

Granular Hemostatic Composite of Alginate, Calcium, and Zinc for Rapid and Effective Management of Post-Traumatic Hemorrhage

Post-traumatic hemorrhage, which can result from accidents or battlefield injuries, is a significant global concern due to the high prehospital mortality rate. Substantial efforts have been made to develop hemostatic agents that can effectively reduce hemorrhage in the immediate aftermath of a traumatic event. The present study investigated the potential efficacy of Ca2+ and Zn2+ supplemented sodium alginate-based dry hemostatic particles (SA-CZ DHP) to manage excessive blood loss or post-traumatic hemorrhage. SA-CZ DHP were developed, followed by their physical and biochemical characterization, cytocompatibility and hemocompatibility testing, and critical evaluation of the hemostatic potential in vitro and in vivo. The safe SA-CZ DHP showed high absorption and accelerated blood clotting kinetics with reduced coagulation time (≈70%, p < 0.0001) in whole human blood, observed with insignificant hemolysis and uninterrupted RBC morphology. SA-CZ DHP significantly reduced the mean blood loss (≈90% in SD rats tail incision), and bleeding time (≈60% in BALB/c mice tail incision) was at par with commercially available Celox hemostatic granules. In conclusion, the biocompatible SA-CZ DHP exhibited rapid and effective management of excessive blood loss. It is also pertinent to note that the developed formulation could be a cost-effective alternative to its commercial counterparts.

In vitro analysis of tantalum-containing mesoporous bioactive glass fibres for haemostasis

Haemorrhage is the leading cause of battlefield deaths and second most common cause for civilian mortality worldwide. Biomaterials-based haemostatic agents are used to aid in bleeding stoppage; mesoporous bioactive glasses (MBGs) are candidates for haemostasis. Previously made Tantalum-containing MBG (Ta-MBG) powders' compositions were fabricated as electrospun fibres for haemostatic applications in the present study. The fibres were fabricated to address the challenges associated with the powder form: difficult to compress without gauze, getting washed away in profuse bleeding, generating dust in the surgical environment, and forming thick callus-difficult to remove for surgeons and painful for patients. Ta-MBGs were based on (80-x)SiO2-15CaO-5P2O5-xTa2O5 mol% compositions with x = 0 (0Ta), 0.5 (0.5Ta), 1 (1Ta), and 5 (5Ta) mol%. The present study details the fibres' in vitro analyses, elucidating their cytotoxic effects, and haemostatic capabilities and relating these observations to fibre chemistry and previously fabricated powders of the same glasses. As expected, when Ta addition is increased at the expense of silica, a new FTIR peak (non-bridging oxygen-silicon, Si-NBO) develops and Si-O-Si peaks become wider. Compared to 0Ta and 1Ta fibres, 0.5Ta show Si-O peaks with reduced intensity. The fibres had a weaker intensity of Si-NBO peaks and release fewer ions than powders. A reduced ion profile provides fibres with a stable matrix for clot formation. The ion release profile for 1Ta and 5Ta fibres was significantly lower than 0Ta and 0.5Ta fibres. Ta-MBGs were not found to be cytotoxic to primary rat fibroblasts using a methyl thiazolyl tetrazolium (MTT) assay. Furthermore, a modified activated partial thromboplastin time assay analysing the fibrin absorbance showed that the absorption increases from physiological clotting < 0Ta < 0.5Ta < 5Ta < commercial haemostat, Surgical SNoWTM, Ethicon, USA < 1Ta. Higher absorption signifies a stronger clot. It is concluded that Ta-MBG fibres can provide stable matrix for clot formation and 1Ta can potentially enhance clotting best among other Ta-MBGs.

Comparison of a gelatin thrombin versus a modified absorbable polymer as a unique treatment for severe hepatic hemorrhage in swine

There are many surgical techniques (packing, Pringle maneuver, etc.) and hemostatic agents to manage hepatic bleeding in trauma surgery. This study compares the effectiveness of two different types of hemostatic agents, one is an active flowable hemostat and the other is a passive hemostat made of modified absorbable polymers [MAP]. Both surgical technique and hemostatic agents can be used together as a means of controlling bleeding. We have hypothesized that a single hemostatic agent might be as effective as a unique hemostatic surgical technique. Twenty swine were prospectively randomized to receive either active Flowable (Floseal) or passive MAP powder (PerClot) hemostatic agents. We used a novel severe liver injury model that caused exsanguinating hemorrhage. The main outcome measure was total blood loss volume. The total volume of blood loss, from hepatic injury to minute 120, was significantly lower in the Flowable group (407.5 cm3; IqR: 195.0-805.0 cm3) compared to MAP group (1107.5 cm3; IqR: 822.5 to 1544.5 cm3) (Hodges-Lehmann median difference: - 645.0 cm3; 95% CI: - 1144.0 to - 280.0 cm3; p = 0.0087). The rate of blood loss was significantly lower in the flowable group compared with the MAP group as measured from time of injury to minutes 3, 9, 12, and 120 (except for 6 min). The mean arterial pressure gradually recovered in the flowable group by 24 h, whereas in the MAP group, the mean arterial pressure was consistently stayed below baseline values. Kaplan-Meier survival analysis indicated similar rates of death between study groups (Logrank test p = 0.3395). Both the flowable and the MAP hemostatic agents were able to effectively control surgical bleeding in a novel severe liver injury model, however, the flowable gelatin-thrombin agent provided quicker and better bleed control.

Progress and future prospects of hemostatic materials based on nanostructured clay minerals

The occurrence of uncontrolled hemorrhage is a significant threat to human life and health. Although hemostatic materials have made remarkable advances in the biomaterials field, it remains a challenge to develop safe and effective hemostatic materials for global medical use. Natural clay minerals (CMs) have long been used as traditional inorganic hemostatic agents due to their good hemostatic capability, biocompatibility and easy availability. With the advancement of science, technology and ideology, CM-based hemostatic materials have undergone continuous innovations by integrating new inspirations with conventional concepts. This review systematically summarizes the hemostatic mechanisms of different natural CMs based on their nanostructures. Moreover, it also comprehensively reviews the latest research progress for CM-based hemostatic hybrid and nanocomposite materials, and discusses the challenges and developments in this field.

Influence of Lavender Essential Oil on the Physical and Antibacterial Properties of Chitosan Sponge for Hemostatic Applications

Uncontrollable bleeding continues to stand as the primary cause of fatalities globally following surgical procedures, traumatic incidents, disasters, and combat scenarios. The swift and efficient management of bleeding through the application of hemostatic agents has the potential to significantly reduce associated mortality rates. One significant drawback of currently available hemostatic products is their susceptibility to bacterial infections at the bleeding site. As this is a prevalent issue that can potentially delay or compromise the healing process, there is an urgent demand for hemostatic agents with antibacterial properties to enhance survival rates. To mitigate the risk of infection at the site of a lesion, we propose an alternative solution in the form of a chitosan-based sponge and antimicrobial agents such as silver nanoparticles (AgNPs) and lavender essential oil (LEO). The aim of this work is to provide a new type of hemostatic sponge with an antibacterial barrier against a wide range of Gram-positive and Gram-negative microorganisms: Staphylococcus epidermidis 2018 and Enterococcus faecalis VRE 2566 (Gram-positive strains) and Klebsiella pneumoniae ATCC 10031 and Escherichia coli ATCC 35218 (Gram-negative strains).

An additive-free multifunctional β-glucan-peptide hydrogel participates in the whole process of bacterial-infected wound healing

Bacterial infections and excessive inflammation can impede the healing of wounds. Hydrogels have emerged as a promising approach for dressing bacterial-infected injuries. However, some antibacterial hydrogels are complex, costly, and even require assistance with other instruments such as light, making them unsuitable for routine outdoor injuries. Here, we developed an in-situ generating hydrogel via hybridizing oxidized β-D-glucan with antimicrobial peptide C8G2 through the Schiff base reaction. This hydrogel is easily accessible and actively contributes to the whole healing process of bacterial-infected wounds, demonstrating remarkable antibacterial activity and biological compatibility. The pH-sensitive reversible imine bond enables the hydrogel to self-heal and sustainably release the antibacterial peptide, thereby improving its bioavailability and reducing toxicity. Meanwhile, the immunoregulating β-D-glucan inhibits the release of inflammatory factors while promoting the release of anti-inflammatory factors. In methicillin-resistant Staphylococcus aureus (MRSA)-infected full-thickness skin wound models, the hybrid hydrogel showed superior antibacterial and anti-inflammatory activity, enhanced the M2 macrophage polarization, expedited wound closure, and regenerated epidermis tissue. These features make this hydrogel an appealing wound dressing for treating multi-drug-resistant bacteria-infected wounds.

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.

Chitosan-Based Biomaterials for Hemostatic Applications: A Review of Recent Advances

Hemorrhage is a detrimental event present in traumatic injury, surgery, and disorders of bleeding that can become life-threatening if not properly managed. Moreover, uncontrolled bleeding can complicate surgical interventions, altering the outcome of surgical procedures. Therefore, to reduce the risk of complications and decrease the risk of morbidity and mortality associated with hemorrhage, it is necessary to use an effective hemostatic agent that ensures the immediate control of bleeding. In recent years, there have been increasingly rapid advances in developing a novel generation of biomaterials with hemostatic properties. Nowadays, a wide array of topical hemostatic agents is available, including chitosan-based biomaterials that have shown outstanding properties such as antibacterial, antifungal, hemostatic, and analgesic activity in addition to their biocompatibility, biodegradability, and wound-healing effects. This review provides an analysis of chitosan-based hemostatic biomaterials and discusses the progress made in their performance, mechanism of action, efficacy, cost, and safety in recent years.

Hemostatic efficacy of a flowable collagen-thrombin matrix during coronary artery bypass grafting: a double-blind randomized controlled trial

BACKGROUND

Flowable hemostatic agents have the advantage of being able to be applied to irregular wound surfaces and difficult to reach areas. We sought to compare the effectiveness and safety of the flowable hemostatic sealants Collastat® (collagen hemostatic matrix, [CHM]) and Floseal® (gelatin hemostatic matrix, [GHM]) during off-pump coronary artery bypass (OPCAB).

METHODS

In this prospective, double-blind, randomized controlled trial, 160 patients undergoing elective OPCAB surgery were enrolled between March 2018 and February 2020. After primary suture of the aortocoronary anastomosis, an area of hemorrhage was identified, and patients received either CHM or GHM (n = 80, each). Study endpoints were the following: proportion of successful intraoperative hemostasis and time required for hemostasis overall postoperative bleeding, proportion of transfusion of blood products, and surgical revision for bleeding.

RESULTS

Of the total patients, 23% were female, and the mean age was 63 years (range 42-81 years). Successful hemostasis proportion within 5 min was achieved for 78 patients (97.5%) in the GHM group, compared to 80 patients (100%) in the CHM group (non-inferiority p = 0.006). Two patients receiving GHM required surgical revision to achieve hemostasis. There were no differences in the mean time required to obtain hemostasis [GHM vs. CHM, mean 1.49 (SD 0.94) vs. 1.35 (0.60) min, p = 0.272], as confirmed by time-to-event analysis (p = 0.605). The two groups had similar amounts of mediastinal drainage for 24 h postoperatively [538.5 (229.1) vs. 494.7 (190.0) ml, p = 0.298]. The CHM group required less packed red blood cells, fresh frozen plasma, and platelets for transfusion than the GHM group (0.5 vs. 0.7 units per patient, p = 0.047; 17.5% vs. 25.0%, p = 0.034; 7.5% vs. 15.0%, p = 0.032; respectively).

CONCLUSIONS

CHM was associated with a lower need for FFP and platelet transfusions. Thus, CHM is a safe and effective alternative to GHM.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04310150.

Current status of hemostatic agents, their mechanism of action, and future directions

The bleeding problem might seem straightforward, but it involves a plethora of complex biochemical pathways and responses. Hemorrhage control remains one of the leading causes of “preventable deaths” worldwide. The past few decades have seen a wide range of biomaterials and their derivatives targeted to serve as hemostatic agents, but none can be deemed as an ideal solution. In this review, we have highlighted the current diversity in hemostatic agents and their modalities. We have enclosed a comprehensive outlook of the proposed solutions and their clinical performance so far. In addition to these, several promising compositions are still in their infancy or developmental phases. The inclusion of novel upcoming nanocomposites has further widened the potencies of existing formulations as well.

The use of sealing hemostat patch (HEMOPATCH®) in laparotomic myomectomy: a prospective case-control study

PURPOSE

Uterine myomas are the most common gynecological disease. In these cases, a myomectomy is performed traditionally laparotomically. However, alternatives have been widely used, including laparoscopic, endoscopic, and robotic surgery. During these techniques, diffuse parenchymatous bleeding remains one of the main intraoperative and postoperative complications and sometimes requires unplanned hysterectomies. Recently, hemostatic agents and sealants have been used to prevent excessive blood loss during surgical repair.

METHODS

We propose a prospective case-control study on the use of a sealing hemostat patch (HEMOPATCH^®) on uterine sutures in laparotomic myomectomy. In the period between July 2016 and April 2017, 46 patients with symptomatic uterine fibromatosis underwent surgery. They were divided into two groups of 23 patients, with different treatments in the hemostatic phase of oozing bleeding. HEMOPATCH^® is applied in group A, and spray electrocoagulation is applied in group B.

RESULTS

In group A, we achieve faster hemostasis (p < 0.05), than in group B. We report a significantly lower C-reactive protein value on the second and third days after surgery for group A compared to group B.

CONCLUSIONS

HEMOPATCH^®, during laparotomic myomectomy, is a valid alternative solution for obtaining rapid hemostasis and consequently intraoperative and postoperative bleeding. Furthermore, we suggest that a lower inflammatory peritoneal state is probably correlated with the barrier effect of the patch on the suture.

Modified cardiopulmonary bypass with low priming volume for blood conservation in cardiac valve replacement surgery

BACKGROUND

The adverse effects of cardiopulmonary bypass during open cardiac surgery, including hemodilution, seem to be inevitable, especially for patients who generally have a relatively lower BMI with relatively small blood volumes. This study reports the modification and use of a cardiopulmonary bypass (CPB) system to reduce priming volume and hemodilution.

METHODS

This is a retrospective study of 462 adult patients who underwent cardiac valve replacement surgery from January 2019 to September 2021 at the General Hospital of Western Theater Command. The modified group consisted of 212 patients undergoing modified CPB. The control group included 250 patients receiving conventional CPB. Evaluated indices included fluid intake and output volumes during CPB, intraoperative indices related to CPB operation, usage of blood products during the peri-CPB period, and postoperative outcomes.

RESULTS

The modified group displayed a significant reduction in the crystalloid (200 mL vs. 600 mL, P < 0.05) and colloid priming volumes (450 mL vs. 1100 mL, P < 0.05), and ultrafiltration solution volume (750 mL vs. 1200 mL, P < 0.05). Furthermore, the modified group had a significantly lower rate of defibrillation (30.2% vs. 41.2%, P < 0.05). The intraoperative urine volume (650 mL vs. 500 mL, P < 0.05) and intraoperative hematocrit (Hct) (26% vs. 24%, P < 0.05) of the modified CPB group were also higher than in the control group. The modified group required a lower infusion volume of packed red blood cells (250 mL vs. 400 mL, P < 0.05) and lower infusion rates of packed red blood cells (17.9% vs. 25.2%, P < 0.05) and fresh frozen plasma (1.41% vs. 5.2%, P < 0.05). In addition, the modified group showed significantly improved indices related to postoperative recovery.

CONCLUSIONS

The modified CPB system effectively conserves blood and shows noteworthy potential for application in cardiac valve replacement surgery.

Safety and Hemostatic Effectiveness of SURGICEL® Powder in Mild and Moderate Intraoperative Bleeding

This postmarket clinical study evaluated the safety and effectiveness of the novel adjunctive topical hemostat SURGICEL® Powder (SURGICEL®-P), a powdered form of oxidized regenerated cellulose. In a prospective, open-label, single-arm multicenter trial, adult surgical subjects with mild-to-moderate bleeding for which conventional hemostatic methods were impractical/ineffective were treated with SURGICEL®-P. Descriptive analyses included hemostatic success rate at 3, 5, and 10 min, rebleeding and thromboembolic events, SURGICEL®-P-related serious adverse events requiring surgical intervention, and SURGICEL®-P ease of use (questionnaire). In 8 centers, 103 subjects were enrolled with a median (range) age of 64.0 (33.0-88.0) years. Surgeries were open (53.4%) or laparoscopic/thoracoscopic (46.6%) and mostly urological (37.9%) and abdominal (32.0%) procedures. Bleeding sites included various tissue types, with a median (range) surface area of 4 (0.02-72.0) cm2. Hemostatic success rates were 77.7%, 87.4%, and 92.2% at 3, 5, and 10 min, respectively. In 7 subjects (6.8%), investigators reverted to standard of care. No safety signals were identified. Two deaths occurred with causes unrelated to SURGICEL®-P. Investigators favorably evaluated the ease of use of the SURGICEL®-P device. SURGICEL®-P is safe and effective in controlling mild-to-moderate bleeding in a broad range of surgical procedures. The trial was registered at https://clinicaltrials.gov as NCT03762200.

Validity of a novel ex vivo porcine liver perfusion model for studying haemostatic products

Introduction

We developed a novel normothermic ex vivo porcine liver perfusion model with whole blood in order to have alternatives for animal experiments in the research and development of new local haemostatic agents. This study aims to assess the construct and content validity of this model.

Methods

In this study we performed two ex vivo experiments using nine livers and one in vivo experiment using six female Norsvin Topigs pigs: (1) ex vivo liver perfusion for establishing physiological blood parameters of the perfused liver and controlled heparinization, (2) ex vivo liver perfusion with a surgical injury and (3) a surgical liver injury in anaesthetized pigs with and without heparin.

Results

Ex vivo coagulation parameters were comparable to in vivo with heparin. Blood gas values and metabolic parameters were comparable between ex vivo and in vivo with heparin, but significantly different compared with in vivo baseline, with the exception of (partial pressure of oxygen (PO2). Activated clotting time (ACT) values significantly differed depending on the heparin doses. The coagulation parameters fibrinogen, activated partial thromboplastin time, prothrombin time and ACT were rather constant during the 4 h ex vivo perfusion. Haemostatic efficacy of commercially available products was comparable between in vivo with heparin and the ex vivo liver perfusion experiment.

Conclusion

This novel ex vivo liver perfusion model demonstrates good construct and content validity for at least 4 h of perfusion. The model is an easily accessible, table-top, tunable and effective alternative for the in vivo testing of (new) haemostatic products on their haemostatic properties. Validité d'un nouveau modèle de perfusion hépatique porcin ex-vivo pour l'étude des produits hémostatiques Résumé

Facing Trauma and Surgical Emergency in Space: Hemorrhagic Shock

Although the risk of trauma in space is low, unpredictable events can occur that may require surgical treatment. Hemorrhage can be a life-threatening condition while traveling to another planet and after landing on it. These exploration missions call for a different approach than rapid return to Earth, which is the policy currently adopted on the International Space Station (ISS) in low Earth orbit (LEO). Consequences are difficult to predict, given the still scarce knowledge of human physiology in such environments. Blood loss in space can deplete the affected astronaut's physiological reserves and all stored crew supplies. In this review, we will describe different aspects of hemorrhage in space, and by comparison with terrestrial conditions, the possible solutions to be adopted, and the current state of the art.

Intraoperative hemostatic agents in orbital surgery

PURPOSE

While preoperative optimization and post-operative management of hemorrhagic complications are increasingly clear, intraoperative control of bleeding during orbital surgery has received less attention. Thanks to advances in other fields, new technologies may be employed during these interventions. This review was designed to discuss these modalities.

METHODS

A literature search was performed to identify manuscripts that are related to the management of intraoperative bleeding. The bibliographies of these studies were also assessed to identify additional references. Data was abstracted from these studies.

RESULTS

Multiple hemostatic agents are currently used in orbital surgery, and related surgical fields have carefully assessed these interventions. Direct mechanical, flowable, and pro-thrombotic medications may all play key roles in achieving hemostasis.

CONCLUSIONS

Orbital surgeons have several potential technologies to facilitate hemostasis, and the armamentarium continues to grow. Future investigations will yield more targeted medications that may be delivered in novel manners to enhance the intraoperative experience.

Hemostatic Efficacy of Absorbable Gelatin Sponges for Surgical Nail Matrixectomy after Phenolization-A Blinded Randomized Controlled Trial

Background: Some studies have recommended combining germinal matrix excision with phenol ablation in the treatment of onychocryptosis. Matrixectomy after phenolization has been shown to be an effective modification to reduce the drawbacks associated with phenolization alone, although it increases the risk of minor postoperative bleeding. The present study aims to assess the effectiveness and safety of gelatin sponges as hemostatic agents in partial matrixectomy after phenolization. Methods: A comparative clinical trial in parallel groups was designed in 74 halluces (44 patients) with stage I, II, and III onychocryptosis. All participants were randomly assigned to 3 groups: Group A (control group), Group B (conventional gelatin sponge), and Group C (high porosity gelatin sponge). Results: The quantified mean blood loss in the first 48 h after surgery in patients in both experimental groups was significantly lower compared to the control group. The lowest mean blood loss was recorded in Group C (p < 0.001) and followed by Group B (p = 0.005). No adverse effects were recorded in any of the patients included in the experimental groups. Conclusions: Hemostatic gelatin sponges were demonstrated to be effective and safe devices for the control of minor postoperative bleeding associated with matrixectomy after segmental phenolization.

In Vitro Evaluation of Real-Time Viscoelastic and Coagulation Properties of Various Classes of Topical Hemostatic Agents Using a Novel Contactless Nondestructive Technology

Hemorrhaging is the main cause of death among combat and civilian injuries and has significant clinical and economic consequences. Despite their vital roles in bleeding management, an optimal topical hemostatic agent (HA) has yet to be developed for a particular scenario. This is partly due to a lack of an overarching quantitative testing technology to characterize the various classes of HAs in vitro. Herein, the feasibility of a novel, contactless, and nondestructive technique to quantitatively measure the shear storage modulus (G') and clotting properties of whole blood in contact with different dosages of eight topical HAs, including particulates and gauze-like and sponge-like systems, was assessed. The real-time G'-time profiles of these blood/HA systems revealed their distinct biomechanical behavior to induce and impact coagulation. These were analyzed to characterize the clot initiation time, clotting rate, clotting time, and apparent stiffness of the formed clots (both immediately and temporally), which were correlated with their reported hemostatic mechanisms of action. Moreover, the HAs that worked independently from the natural blood clotting cascade were identified and quantified through this technology. In sum, this study indicated that the nondestructive nature of the technology may offer a promising tool for accurate, quantitative in vitro measurements of the clotting properties of various classes of HAs, which may be used to better predict their in vivo outcomes.

Engineered Molecular Therapeutics Targeting Fibrin and the Coagulation System: a Biophysical Perspective

The coagulation cascade represents a sophisticated and highly choreographed series of molecular events taking place in the blood with important clinical implications. One key player in coagulation is fibrinogen, a highly abundant soluble blood protein that is processed by thrombin proteases at wound sites, triggering self-assembly of an insoluble protein hydrogel known as a fibrin clot. By forming the key protein component of blood clots, fibrin acts as a structural biomaterial with biophysical properties well suited to its role inhibiting fluid flow and maintaining hemostasis. Based on its clinical importance, fibrin is being investigated as a potentially valuable molecular target in the development of coagulation therapies. In this topical review, we summarize our current understanding of the coagulation cascade from a molecular, structural and biophysical perspective. We highlight single-molecule studies on proteins involved in blood coagulation and report on the current state of the art in directed evolution and molecular engineering of fibrin-targeted proteins and polymers for modulating coagulation. This biophysical overview will help acclimatize newcomers to the field and catalyze interdisciplinary work in biomolecular engineering toward the development of new therapies targeting fibrin and the coagulation system.

Biomaterials as Haemostatic Agents in Cardiovascular Surgery: Review of Current Situation and Future Trends

Intraoperative haemostasis is of paramount importance in the practice of cardiovascular surgery. Over the past 70 years, topical haemostatic methods have advanced significantly and today we deal with various haemostatic agents with different properties and different mechanisms of action. The particularity of coagulation mechanisms after extracorporeal circulation, has encouraged the introduction of new types of topic agents to achieve haemostasis, where conventional methods prove their limits. These products have an important role in cardiac, as well as in vascular, surgery, mainly in major vascular procedures, like aortic dissections and aortic aneurysms. This article presents those agents used for topical application and the mechanism of haemostasis and offers general recommendations for their use in the operating room.

Comparison of modified rapid deployment hemostat dressing with standard haemostat as part of standardized perihepatic packing for major liver trauma in a level 1 trauma center

Introduction

Uncontrolled hemorrhage is a major cause of mortality in surgery and trauma. Damage control surgery (DCS) is essential in the management of these cases. The use of topical hemostatic agents has increased over the last two decades with the evolution of DCS and trauma-induced coagulopathy. The aim of this study was to compare the performance of standard perihepatic packing with the addition of either a MRDH (modified rapid deployment hemostat) or a non-MRDH hemostatic dressing.

Methods

This was a retrospective, comparative analysis of prospectively collected data held in the registry of a level I trauma center in Bologna, Italy, between 2005 and 2019. 33 patients with grade IV/V liver injuries who underwent a standardized perihepatic packing with hemostatic dressings were enrolled in the study. The study group included 21 patients treated with standard packing plus MRDH. The control group included 12 patients treated with standard packing plus a combination of fibrillar absorbable hemostat and human fibrin sealant.

Results

The two groups were homogeneous in terms of age and American Association for the Surgery of Trauma (AAST) grade although the MRDH one seemed to have more severe injury: hemodynamic instability was present in 95% of MRDH patients vs. 83% in the control group. Also, Injury Severity Score (ISS) and New Injury Severity Score (NISS) were 41 vs 35.5 and 47 vs 39.1, respectively. The incidence of re-bleeding requiring repacking at the second-look laparotomy was 4.7% in MRDH patients vs. 16.7% in non-MRDH patients ( p = .5, OR = 4). The overall complication rate was of 23% after the introduction of MRDH vs. 81% in the control group.

Conclusion

Despite the potential effectiveness of MRDH, this study does not seem to confirm a significant superiority of this hemostat over the standard.

Biomaterials for Hemostasis

Uncontrolled bleeding is a major problem in trauma and emergency medicine. While materials for trauma applications would certainly find utility in traditional surgical settings, the unique environment of emergency medicine introduces additional design considerations, including the need for materials that are easily deployed in austere environments. Ideally, these materials would be available off the shelf, could be easily transported, and would be able to be stored at room temperature for some amount of time. Both natural and synthetic materials have been explored for the development of hemostatic materials. This review article provides an overview of classes of materials used for topical hemostats and newer developments in the area of injectable hemostats for use in emergency medicine. Expected final online publication date for the Annual Review of Biomedical Engineering, Volume 24 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Hemoglobin Precipitation: An Index of In Vitro Vasoconstrictive Activities of Methanol Leaf Extracts of Croton megalocarpus Hutch and Lantana camara Linn

The function of innate hemostasis aids the body in bleeding control, preventing the loss of excessive amounts of blood following low-degree injuries. However, injuries of a higher degree may require extrinsic intervention to stop life-threatening blood loss. Astringent agents' actions result in mechanical constriction of small blood vessels and shrinkage of body tissues, thereby stopping blood loss. This enhances the primary phase of hemostasis, where vasoconstriction is the main mechanism at play during the initial response to injury. The effects of plant extracts on protein precipitation have been linked to blood vessel vasoconstriction. Traditionally, the leaves of Croton megalocarpus Hutch and Lantana camara Linn plants are used by communities living in Makueni County, Kenya, for peripheral bleeding control. However, the effects of extracts of both plants on hemoglobin precipitation have not been evaluated scientifically. In the current study, the activities of methanol extracts of C. megalocarpus (H.) and L. camara (L.) on blood protein precipitation were investigated. The leaves were harvested, cleaned, air-dried, milled, and extracted in absolute methanol before being concentrated into dry powders. A qualitative phytochemical screen revealed the presence of terpenoids, steroids, tannins, phenols, flavonoids, reducing sugars, cardiac glycosides, and carbohydrates in the methanol extract of C. megalocarpus (H.). The methanol extracts of L. camara (L.) contained cardiac glycosides, saponins, tannins, phenols, terpenoids, reducing sugars, and carbohydrates. The hemoglobin precipitation ability of various concentrations of extracts using mice samples was presented as relative astringency following the tannic acid external standard method. Methanol extracts C. megalocarpus (H.) and L. camara (L.) had significantly higher relative astringency compared with the normal control, indicating a protein precipitating activity. The relative astringency observed in both plant extracts is linked to the activity of tannins, phenols, flavonoids, and saponins detected during preliminary phytochemical screening.

Highly resilient, biocompatible, and antibacterial carbon nanotube/hydroxybutyl chitosan sponge dressing for rapid and effective hemostasis

Uncontrolled hemorrhage is the leading cause of trauma death. The development of safe and efficient hemostatic agents that can rapidly and effectively control bleeding is of great significance to rescue the injured. However, the mechanical, absorptive, and antibacterial properties of conventional two-dimensional hemostatic agents are not satisfactory. Herein, a series of effective three-dimensional hemostatic dressings (JWCNT/HBC sponges) are developed by chemical modification of joint-welded carbon nanotube (JWCNT) sponges with hydroxybutyl chitosan (HBC) for hemorrhage hemostasis. The JWCNT/HBC sponges exhibit high elasticity, porous structure, and suitable blood-absorption and blood-maintaining performance. Moreover, the introduction of HBC endows the JWCNT/HBC sponges with favorable blood compatibility and good antibacterial activity. The sponge treated with 0.5% HBC (JWCNT/0.5%HBC sponge) displays better antiseptic capability, faster blood clotting ability in vitro and shorter hemostasis time in vivo than the commercial gelatin sponge. The JWCNT/HBC sponges combine the advantages of JWCNT sponges and HBC in the adhesion and activation of platelets and red blood cells, thus becoming a good medical material for trauma hemostasis.

Topical Coagulant Agents

Topical hemostatic agents have continued to develop as knowledge of coagulation physiology and pathophysiology has evolved. The addition of knowledge of hemostatic agents to a surgeon's armamentarium helps to push the boundaries of life-saving care. As the understanding of the complex physiology of coagulation and hemorrhage improves, so will the potential for developing hemostatic agents that are safe, affordable, and readily available. This article discusses topical coagulant agents and hemostatic materials currently available in the surgery. The relevant agents/materials, their characteristics, different utility in surgical hemostasis, and their relevant benefits and drawbacks are reviewed.

Topical hemostatic agents in neurosurgery, a comprehensive review: 15 years update

Hemostasis in neurosurgery is of utmost importance. Bleeding management is one of the crucial steps of each neurosurgical procedure. Several strategies, namely thermal, mechanical, electric, and chemical, have been advocated to face blood loss within the surgical field. Over time, countless hemostatic agents and devices have been proposed. Furthermore, the ever-growing recent technological innovation has made available several novel and interesting tools. Pursuant to their impact on surgical practice, we perceived the imperative to update our previous disclosure paper. Therefore, we reviewed the literature and analyzed technical data sheets of each product in order to provide an updated and comprehensive overview in regard to chemical properties, mechanisms of action, use, complications, tricks, and pitfalls of topical hemostatic agents.

The Use of Hemostatic Agents to Decrease Bleeding Complications in General Plastic Surgery Procedures

Within plastic surgery, hematomas and seromas are frequently reported complications that can negatively impact wound healing and result in significant morbidity in patients. As a result, there has been considerable interest in hemostatic agents to complement traditional methods of hemostasis. The purpose of this study was to evaluate postoperative bleeding complications and duration of Jackson-Pratt (JP) drain use in general plastic surgery procedures with and without hemostatic agents.

Hemostatic dressings based on poly(vinyl formal) sponges

The development of novel hemostatic agents is related to the fact that severe blood loss due to hemorrhage continues to be the leading cause of preventable death of patients with military trauma and the second leading cause of death of civilian patients with injuries. Herein we assessed the hemostatic properties of porous sponges based on biocompatible hydrophilic polymer, poly(vinyl formal) (PVF), which meets the main requirements for the development of hemostatic materials. A series of composite hemostatic materials based on PVF sponges with different porosities and fillers were synthesized by acetalization of poly(vinyl alcohol) with formaldehyde. Nano-sized aminopropyl silica, micro-sized calcium carbonate, and chitosan hydrogel were used to modify PVF matrixes. The physicochemical properties (pore size, elemental composition, functional groups, hydrophilicity, and acetalization degree) of the synthesized composite sponges were studied by gravimetrical analysis, optical microscopy, scanning electron microscopy combined with energy dispersive x-ray spectroscopy, infrared spectroscopy, and nuclear magnetic resonance. Hemostatic properties of the materials were assessed using a model of parenchymal bleeding from the liver of white male Wistar rat with a gauze bandage as a control. All investigated PVF-based porous sponges showed high hemostatic activity: upon the application of PVF-samples the bleeding decreased within 3 min by 68.4-94.4% (р < 0.001). The bleeding time upon the application of PVF-based composites decreased by 78.3-90.4% (p < 0.001) compared to the application of well-known commercial product Celox™.

In vivo Hemostatic Activity of Jatropha mollissima: A Triple-Blinded, Randomized, Controlled Trial in an Animal Model

Objective The objective of this study was to evaluate the hemostatic activity of the sap from Jatropha mollissima (Pohl) Baill. in rats.

Materials and Methods Twenty-four Wistar rats were randomized into four groups ( n = 6): the JM25 and JM40 groups were treated with ethanolic extract from the sap of J. mollissima , in a concentration of 25 and 40 mg·mL ¹ , respectively; the MO group was treated with Monsel’s solution and the control group SC with a 0.9% sodium chloride solution.

Statistical Analysis Data were submitted to the Kurskal–Wallis’ test, followed by Dunn’s post hoc ( p < 0.05).

Results There was a significant reduction in the bleeding time of the group from the JM25 extract ( p = 0.001) when compared with MO and SC. There were no statistically significant differences between groups JM25 and JM40 ( p > 0.05). The JM25 group did not present rebleeding, a result significantly different from the MO group ( p = 0.001). Monsel’s solution showed significant bleeding, six times greater than the control group SC.

Conclusion The J. mollissima extract, in the concentration of 25 mg·mL ¹ , showed the highest hemostatic efficiency and was found to be a promising biomaterial for the elaboration of a hemostatic product.

Thrombin immobilized polydopamine-diatom biosilica for effective hemorrhage control

In this study, an efficient composite hemostatic material (DA-diatom-T) was prepared, using a polydopamine layer as a linker to immobilize thrombin on the surface of diatom biosilica. DA-diatom-T retained the porous structure of the diatom with high water absorption capacity, which can absorb 31 times its own weight of water. The thrombin activity of DA-diatom-T was as high as 5.81 U mg-1 that could be maintained at 67% after 30 days at room temperature. DA-diatom-T exhibited non-toxicity to mouse fibroblast cell lines, favorable hemocompatibility and fast procoagulant ability. DA-diatom-T could promote the initiation of the coagulation process and increase platelet activity and blood clot strength to form a physical barrier at the wound. In an in vivo study, DA-diatom-T could significantly reduce the clotting time and reduce the bleeding volume. The above results showed that DA-diatom-T had potential as a new hemostatic material.

Anaphylaxis after injecting a hemostatic agent containing gelatin into vertebral bone under pressure-a warning

STUDY DESIGN

Case series.

PURPOSE

The use of topical hemostatic agents is common in spinal deformity surgery. While beneficial, emerging case data shows gelatin-containing agents causing intra-operative complications. We present two patients who developed anaphylaxis after injection of these gelatin-containing hemostatic agents into the vertebral body using manual pressure. In the literature, while anaphylactic reactions associated with the use of animal-derived gelatin has been implicated; the risk of injecting these products into the closed vascular cavity of the vertebral body with subsequent embolization into systemic circulation bears emphasis. This report is to meant to make the surgical team aware of the risks of injecting hemostatic agents using manual pressure into the vertebral body and to highlight a plausible mechanism for the phenomenon.

METHODS

Two children with spinal deformity undergoing posterior spinal fusion procedures with the use of gelatin-containing hemostatic agents injected into the vertebral body through the pedicle are described.

RESULTS

Both patients had gelatin-containing hemostatic agent solution injected under manual pressure through the vertebral pedicle to prevent excessive bleeding. Anaphylaxis occurred soon thereafter, resulting in emergent cessation of the surgery and initiation of medical resuscitation. In both cases, tryptase levels obtained just after the event were elevated.

CONCLUSION

Patients with an allergy to or prior history of exposure to zoologic products undergoing spine surgery may be at risk of anaphylaxis if the gelatin-containing hemostatic agent is injected under manual pressure into the closed space of the vertebral body. This allows rapid entry into the venous circulation. We recommend that the surgeon perform a thorough history of a patient's allergies and use extreme caution when injecting these topical hemostatic products into the vertebral body.

LEVEL OF EVIDENCE

IV.

Efficacy and Safety of Bioabsorbable Bone Hemostatic Agent in Total Knee Arthroplasty: A Prospective Randomized Controlled Trial

Although a bioabsorbable bone hemostatic agent (BBHA) was developed approximately 20 years ago to overcome the shortcomings of conventional bone wax, its bleeding control capacity has not yet been studied. This study was aimed at investigating the efficacy and safety of BBHA in total knee arthroplasty (TKA). Sixty-two patients who underwent unilateral primary TKA for knee osteoarthritis were included and randomized to the control or BBHA group. Before releasing the tourniquet, BBHA was applied on the bone-cut surface that was not covered by implants. The primary variable was the drainage volume during the postoperative period. The secondary outcomes were total estimated blood loss (EBL), hemoglobin level, hematocrit level, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, range of motion (ROM), pain visual analog scale (VAS) score, and rate of complications. There were no significant differences in drainage volume or EBL between the 2 groups. Hemoglobin and hematocrit levels were higher in the BBHA group during the 4-week postoperative period; however, the intergroup differences were not significant. The ESR, CRP, ROM, and pain VAS scores in the BBHA group were not significantly different from the corresponding values in the control group. No specific complications were observed. Although BBHA was found to be safe without complications, it did not decrease bleeding after TKA in general cases. Further studies are necessary to evaluate the efficacy of BBHA in patients with coagulation problems.

Battlefield Medicine: Anesthesia and Critical Care in the Combat Zone

The US Military Joint Trauma System has been developed to mitigate the harsh conditions under which medical providers care for combat casualties and provide continuity of care from the battlefield to US medical centers. We review the components of this system with emphasis on combat trauma care under fire and the role of the anesthesiologist and intensivist in this continuum of care. An important link in the chain of survival is the Air Force Critical Care Aeromedical Transport Team, which provides critical care while transporting casualties from the theater to higher levels of care outside the war zone and home.

Hemostatic and Tissue Regeneration Performance of Novel Electrospun Chitosan-Based Materials

The application of chitosan (Ch) as a promising biopolymer with hemostatic properties and high biocompatibility is limited due to its prolonged degradation time, which, in turn, slows the repair process. In the present research, we aimed to develop new technologies to reduce the biodegradation time of Ch-based materials for hemostatic application. This study was undertaken to assess the biocompatibility and hemostatic and tissue-regeneration performance of Ch-PEO-copolymer prepared by electrospinning technique. Chitosan electrospinning membranes (ChEsM) were made from Ch and polyethylene oxide (PEO) powders for rich high-porous material with sufficient hemostatic parameters. The structure, porosity, density, antibacterial properties, in vitro degradation and biocompatibility of ChEsM were evaluated and compared to the conventional Ch sponge (ChSp). In addition, the hemostatic and bioactive performance of both materials were examined in vivo, using the liver-bleeding model in rats. A penetrating punch biopsy of the left liver lobe was performed to simulate bleeding from a non-compressible irregular wound. Appropriately shaped ChSp or ChEsM were applied to tissue lesions. Electrospinning allows us to produce high-porous membranes with relevant ChSp degradation and swelling properties. Both materials demonstrated high biocompatibility and hemostatic effectiveness in vitro. However, the antibacterial properties of ChEsM were not as good when compared to the ChSp. In vivo studies confirmed superior ChEsM biocompatibility and sufficient hemostatic performance, with tight interplay with host cells and tissues. The in vivo model showed a higher biodegradation rate of ChEsM and advanced liver repair.

Design and Preclinical Evaluation of Chitosan/Kaolin Nanocomposites with Enhanced Hemostatic Efficiency

In the current study, hemostatic compositions including a combination of chitosan and kaolin have been developed. Chitosan is a marine polysaccharide derived from chitins, a structural component in the shells of crustaceans. Both chitosan and kaolin have the ability to mediate a quick and efficient hemostatic effect following immediate application to injury sites, and thus they have been widely exploited in manufacturing of hemostatic composites. By combining more than one hemostatic agent (i.e., chitosan and kaolin) that act via more than one mechanism, and by utilizing different nanotechnology-based approaches to enhance the surface areas, the capability of the dressing to control bleeding was improved, in terms of amount of blood loss and time to hemostasis. The nanotechnology-based approaches utilized to enhance the effective surface area of the hemostatic agents included the use of Pluronic nanoparticles, and deposition of chitosan micro- and nano-fibers onto the carrier. The developed composites effectively controlled bleeding and significantly improved hemostasis and survival rates in two animal models, rats and rabbits, compared to conventional dressings and QuikClot^® Combat Gauze. The composites were well-tolerated as demonstrated by their in vivo biocompatibility and absence of clinical and biochemical changes in the laboratory animals after application of the dressings.