New hemostatic device for grade IV-V liver injury in porcine model: a proof of concept

A Novel Approach to Noncompressible Torso Hemorrhage Using a Silicone-Based Polymer Universal Combat Matrix

INTRODUCTION

Battlefield trauma necessitates prompt hemostatic intervention to mitigate fatalities resulting from critical blood loss. Insights from Operation Enduring Freedom and Operation Iraqi Freedom emphasize the limitations of conventional methods, such as tourniquets, especially in noncompressible torso hemorrhage. Despite advancements in hemostatic agents, the evolving dynamics of multidomain operations necessitate novel, lightweight strategies for hemorrhage control. This study investigates the Silicone-Based Polymer (SBP) Universal Combat Matrix (UCM) by SiOxMed, a multimodal matrix exhibiting efficacy in lethal hemorrhage models. The study evaluates UCM's multiday hemostatic capabilities in a noncompressible torso hemorrhage model, offering pivotal insights for potential deployment in battlefield trauma.

MATERIALS AND METHODS

This research was performed under Institutional Animal Care and Use Committee approval and was designed to replicate austere conditions in an off-site enclosed facility. Yorkshire Hampshire swine underwent baseline assessments and anesthesia induction (n = 3). A Grade IV liver injury was made by incising X-shaped lesions, each measuring 4 cm × 2.5 cm, into the diaphragmatic surface of the left and right middle lobes using a scalpel blade, resulting in a lesion region of approximately 3 cm × 6 cm × 3 cm, followed by 30 seconds of uncontrolled bleeding. The injuries were then treated with SBP. Intensive care unit monitoring for 1 hour ensured sustained hemostasis, followed by 48 hours of postanesthesia monitoring and then a return to the operating table to visualize sustained hemostasis. Posteuthanasia, liver tissue underwent histological assessments to evaluate the hemorrhagic interface and liver tissue reactivity.

RESULTS

The average time to hemostatic control was 247.3 ± 71.3 seconds. Stable heart rate (81.3 ± 10.0) and respiratory rate (31.7 ± 16.5) were maintained during intensive care unit monitoring. All swine survived the 1-hour anesthesia monitoring period and the subsequent 48-hour monitoring (average survival time, 48.0 hours ± 0.0, n = 3). Visualization of the abdominal cavity at 48 hours revealed no hemorrhage. Histological assessment demonstrated aligned red blood cells and stratified layers of fibrin at the hemorrhagic interface. Masson's Trichrome analysis demonstrated a reactive and regenerative scenario 48 hours postinjury, with a collagen membrane demarcating uninjured and exposed liver regions, along with a comprehensive stromal response.

CONCLUSIONS

In conclusion, our investigation into the SBP UCM hemostatic efficacy in a grade IV liver laceration model demonstrates its rapid and reliable action in controlling bleeding, showcasing practicality with an average mass of 4.0 ± 1.0 g. Silicone-Based Polymer sustained hemostasis without adverse physiological effects, as evidenced by stable parameters and the survival of all swine during and after anesthesia. Macroscopic examination at 48 hours revealed durable adherence with no indications of hemorrhage. Histological evaluations highlighted SBP's role in stable clot formation, fibrinogenesis, and tissue regeneration, indicating its potential as a multimodal wound dressing. Although promising, the study has limitations, emphasizing the need for future research with larger samples and controls. This work sets the stage for exploring SBP's clinical implications, particularly in scenarios where lightweight, multimodal technologies are crucial for addressing traumatic injuries and enhancing military medical capabilities.

Experimental Models of Traumatic Injuries: Do They Capture the Coagulopathy and Underlying Endotheliopathy Induced by Human Trauma?

Trauma-induced coagulopathy (TIC) is a major cause of morbidity and mortality in patients with traumatic injury. It describes the spectrum of coagulation abnormalities that occur because of the trauma itself and the body's response to the trauma. These coagulation abnormalities range from hypocoagulability and hyperfibrinolysis, resulting in potentially fatal bleeding, in the early stages of trauma to hypercoagulability, leading to widespread clot formation, in the later stages. Pathological changes in the vascular endothelium and its regulation of haemostasis, a phenomenon known as the endotheliopathy of trauma (EoT), are thought to underlie TIC. Our understanding of EoT and its contribution to TIC remains in its infancy largely due to the scarcity of experimental research. This review discusses the mechanisms employed by the vascular endothelium to regulate haemostasis and their dysregulation following traumatic injury before providing an overview of the available experimental in vitro and in vivo models of trauma and their applicability for the study of the EoT and its contribution to TIC.

Inflammatory response to the ischaemia-reperfusion insult in the liver after major tissue trauma

BACKGROUND

Polytrauma is often accompanied by ischaemia-reperfusion injury to tissues and organs, and the resulting series of immune inflammatory reactions are a major cause of death in patients. The liver is one of the largest organs in the body, a characteristic that makes it the most vulnerable organ after multiple injuries. In addition, the liver is an important digestive organ that secretes a variety of inflammatory mediators involved in local as well as systemic immune inflammatory responses. Therefore, this review considers the main features of post-traumatic liver injury, focusing on the immuno-pathophysiological changes, the interactions between liver organs, and the principles of treatment deduced.

METHODS

We focus on the local as well as systemic immune response involving the liver after multiple injuries, with emphasis on the pathophysiological mechanisms.

RESULTS

An overview of the mechanisms underlying the pathophysiology of local as well as systemic immune responses involving the liver after multiple injuries, the latest research findings, and the current mainstream therapeutic approaches.

CONCLUSION

Cross-reactivity between various organs and cascade amplification effects are among the main causes of systemic immune inflammatory responses after multiple injuries. For the time being, the pathophysiological mechanisms underlying this interaction remain unclear. Future work will continue to focus on identifying potential signalling pathways as well as target genes and intervening at the right time points to prevent more severe immune inflammatory responses and promote better and faster recovery of the patient.

A novel inflatable device for perihepatic packing and hepatic hemorrhage control: A proof-of-concept study

INTRODUCTION

Uncontrolled bleeding is the primary cause of death in complex liver trauma and perihepatic packing is regularly utilized for hemorrhage control. The purpose of this study was to investigate the effectiveness of a novel inflatable device (the airbag) for perihepatic packing using a validated liver injury damage control model in swine.

MATERIAL AND METHODS

The image of the human liver was digitally isolated within an abdominal computerized tomography scan to produce a silicone model of the liver to mold the airbag. Two medical grade polyurethane sheets were thermal bonded to the configuration of the liver avoiding compression of the hepatic pedicle, hepatic veins, and the suprahepatic vena cava after inflation. Yorkshire pigs (n = 22) underwent controlled hemorrhagic shock (35% of the total blood volume), hypothermia, and fluid resuscitation to reproduce the indications for damage control surgery (coagulopathy, hypothermia, and acidosis) prior to a liver injury. A 3 × 10 cm rectangular segment of the left middle lobe of the liver was removed to create the injury. Subsequently, the animals were randomized into 4 groups for liver damage control (240 min), Sponge Pack (n = 6), Pressurized Airbag (n = 6), Vacuum Airbag (n = 6), and Uncontrolled (n = 4). Animals were monitored throughout the experiment and blood samples obtained.

RESULTS

Perihepatic packing with the pressurized airbag led to significantly higher mean arterial pressure during the liver damage control phase compared to sponge pack and vacuum airbag 52 mmHg (SD 2.3), 44.9 mmHg (SD 2.1), and 32 mmHg (SD 2.3), respectively (p < 0.0001), ejection fraction was also higher in that group. Hepatic hemorrhage was significantly lower in the pressurized airbag group compared to sponge pack, vacuum airbag, and uncontrolled groups; respectively 225 ml (SD 160), 611 ml (SD 123), 991 ml (SD 385), 1162 ml (SD 137) (p < 0001). Rebleeding after perihepatic packing removal was also significantly lower in the pressurized airbag group; respectively 32 ml (SD 47), 630 ml (SD 185), 513 ml (SD 303), (p = 0.0004). Intra-abdominal pressure remained similar to baseline, 1.9 mmHg (SD 1), (p = 0.297). Histopathology showed less necrosis at the border of the liver injury site with the pressurized airbag.

CONCLUSION

The pressurized airbag was significantly more effective at controlling hepatic hemorrhage and improving hemodynamics than the traditional sponge pack technique. Rebleeding after perihepatic packing removal was negligible with the pressurized airbag and it did not provoke hepatic injury.

Related substances method development and validation of an LCMS/MS method for quantification of selexipag and its related impurities in rat plasma and its application to pharmacokinetic studies

The present application wish to seem at the event of validation of bio analytical method and pharmacokinetic study of selexipag and its related impurities in rat plasma using LC–MS/MS. The optimized method contains gradient elution of selexipag with a flow rate of 1 ml/min and X-Bridge phenyl column (150 × 4.6 mm, 3.5 µ). A buffer of 1 mL formic acid in l liter water and acetonitrile mixture is used as mobile phase. 30 min run time was used for separation of selexipag and its related impurities with Ambrisentan as internal standard and impurity-D as active metabolite. The linearity curves are linear in between the percentages of 10 to 200% of rat plasma and R2 value of each analyte was observed as 0.999. This application denotes all the parameters like precision, accuracy, recovery and stability were got the results within the limit of USFDA guidelines. This method applies effectively for the investigation of pharmacokinetic studies using rat plasma.

Comparison of hemostatic efficacy of topical Ankaferd Blood Stopper on heparinized and nonheparinized rats in bleeding related to liver injury

PURPOSE

In this study, hemostatic efficacy of Ankaferd Blood Stopper (ABS), a new generation hemostatic agent, was compared in the presence of heparin effect.

METHODS

Forty-eight Wistar albino rats were divided into two main groups as heparinized and nonheparinized, and these two main groupswere divided into six subgroups as control, Surgicel and ABS (n = 8). Grade 2 liver injury was performed on rats as standard. All groups were compared in terms of weight, laceration surface area, prothrombin time (PT), activated partial thromboplastin time (aPTT), international normalized ratio (INR), bleeding time, bleeding amount, hemoglobin (Hb) levels, macroscopic and microscopic reactions to the agent used.

RESULTS

Whereas there was no statistically significant difference between weight, laceration surface area, PT, INR and preoperative Hb values in the heparinized and nonheparinized groups, postoperative Hb, bleeding time, bleeding amount and aPTT values were statistically different (p < 0.05). In the heparin-hemostat interaction, the ABS group had the lowest bleeding in the heparinized group in terms of the amount of bleeding compared to the control and Surgicel groups (F = 0.764; p = 0.047). In macroscopic and microscopic comparison, there was no difference between the groups in terms of cell necrosis andfresh bleeding (p > 0.05), it was found that the Surgicel group had statistical significantly higher reaction scores (p < 0.05) than the other groups in terms of other parameters.

CONCLUSIONS

Ankaferd Blood Stopper can be safely and effectively used in surgical practice and in patients with additional diseases requiring heparinization, since it causes minimal reaction in the liver and decreases the amount of bleeding especially in the heparinized group.