Thrombin use in surgery: an evidence-based review of its clinical use

A Case of Intraoperative Anaphylaxis Caused by Bovine-Derived Thrombin

Intraoperative bovine-derived topical thrombin is still widely used for hemostasis during surgery. A 38-year-old woman with chronic spontaneous urticaria was referred to the orthopedic surgery department for herniated disk and myelopathy. During the first stage of operation, bovine-derived thrombin powder soaked in Gelfoam was used as a hemostatic aid. After 30 minutes, the patient developed anaphylactic shock with systemic skin rash and angioedema. Repeated intravenous bolus and infusion of vasopressor were carried out, and her blood pressure normalized. Skin test and specific immunoglobulin E test showed positive results for bovine thrombin and beef, respectively. During the second stage of operation (After 10 days from first stage of operation), bovine-derived thrombin powder was excluded and the operation was successful without any unexpected events. Therefore, bovine thrombin should be used with caution because it might cause anaphylaxis.

Biomaterials and Advanced Technologies for Hemostatic Management of Bleeding

Bleeding complications arising from trauma, surgery, and as congenital, disease-associated, or drug-induced blood disorders can cause significant morbidities and mortalities in civilian and military populations. Therefore, stoppage of bleeding (hemostasis) is of paramount clinical significance in prophylactic, surgical, and emergency scenarios. For externally accessible injuries, a variety of natural and synthetic biomaterials have undergone robust research, leading to hemostatic technologies including glues, bandages, tamponades, tourniquets, dressings, and procoagulant powders. In contrast, treatment of internal noncompressible hemorrhage still heavily depends on transfusion of whole blood or blood's hemostatic components (platelets, fibrinogen, and coagulation factors). Transfusion of platelets poses significant challenges of limited availability, high cost, contamination risks, short shelf-life, low portability, performance variability, and immunological side effects, while use of fibrinogen or coagulation factors provides only partial mechanisms for hemostasis. With such considerations, significant interdisciplinary research endeavors have been focused on developing materials and technologies that can be manufactured conveniently, sterilized to minimize contamination and enhance shelf-life, and administered intravenously to mimic, leverage, and amplify physiological hemostatic mechanisms. Here, a comprehensive review regarding the various topical, intracavitary, and intravenous hemostatic technologies in terms of materials, mechanisms, and state-of-art is provided, and challenges and opportunities to help advancement of the field are discussed.

Bioengineering the Endocrine Pancreas: Intraomental Islet Transplantation Within a Biologic Resorbable Scaffold

Transplantation of pancreatic islets is a therapeutic option to preserve or restore β-cell function. Our study was aimed at developing a clinically applicable protocol for extrahepatic transplantation of pancreatic islets. The potency of islets implanted onto the omentum, using an in situ-generated adherent, resorbable plasma-thrombin biologic scaffold, was evaluated in diabetic rat and nonhuman primate (NHP) models. Intraomental islet engraftment in the biologic scaffold was confirmed by achievement of improved metabolic function and preservation of islet cytoarchitecture, with reconstitution of rich intrainsular vascular networks in both species. Long-term nonfasting normoglycemia and adequate glucose clearance (tolerance tests) were achieved in both intrahepatic and intraomental sites in rats. Intraomental graft recipients displayed lower levels of serum biomarkers of islet distress (e.g., acute serum insulin) and inflammation (e.g., leptin and α2-macroglobulin). Importantly, low-purity (30:70% endocrine:exocrine) syngeneic rat islet preparations displayed function equivalent to that of pure (>95% endocrine) preparations after intraomental biologic scaffold implantation. Moreover, the biologic scaffold sustained allogeneic islet engraftment in immunosuppressed recipients. Collectively, our feasibility/efficacy data, along with the simplicity of the procedure and the safety of the biologic scaffold components, represented sufficient preclinical testing to proceed to a pilot phase I/II clinical trial.

Application of Functional Genomics for Bovine Respiratory Disease Diagnostics

Bovine respiratory disease (BRD) is the most common economically important disease affecting cattle. For developing accurate diagnostics that can predict disease susceptibility/resistance and stratification, it is necessary to identify the molecular mechanisms that underlie BRD. To study the complex interactions among the bovine host and the multitude of viral and bacterial pathogens, as well as the environmental factors associated with BRD etiology, genome-scale high-throughput functional genomics methods such as microarrays, RNA-seq, and proteomics are helpful. In this review, we summarize the progress made in our understanding of BRD using functional genomics approaches. We also discuss some of the available bioinformatics resources for analyzing high-throughput data, in the context of biological pathways and molecular interactions. Although resources for studying host response to infection are avail-able, the corresponding information is lacking for majority of BRD pathogens, impeding progress in identifying diagnostic signatures for BRD using functional genomics approaches.

Efficacy of a topical bovine-derived thrombin solution as a hemostatic agent in a rodent model of hepatic injury

Hemorrhage is a major concern in patients undergoing hepatic surgery or in those with hepatic trauma. In these cases, employing traditional hemostatic strategies can be problematic due to the diffuse nature of hepatic hemorrhage and limited opportunities for direct hemostasis. This study assessed the efficacy of a bovine-derived thrombin solution, (BT), as a topical liquid agent to augment hemostasis and survival following severe hepatic hemorrhage in a rat model. Heart rate (HR), arterial blood pressure (ABP), packed cell volume (PCV), and overall survival were evaluated in 54 rats randomly assigned to receive topical application of BT, saline, or suture ligation applied immediately to a liver lobe following controlled laceration. Six additional rats received liver laceration with no applied treatment. Intravenous fluid resuscitation was initiated and HR and ABP were recorded for 60 min, after which survivors were recovered from anesthesia. Rats were then monitored for 72 h, after which survivors were euthanized. There was no significant difference in survival time, percentage survival, intra-operative ABP or HR, or post-operative PCV between treatment groups. There is insufficient evidence to recommend BT as the sole therapy using this delivery method for mitigating severe hemorrhage from liver injury.