Fibrin/Thrombin Patches and Glues in a Pre-Clinical Model of Endoscopic Skull Base Hemorrhage

Introduction: As indications and approaches in endoscopic skull base surgery expand, the potential for major vessel hemorrhage in areas that are relatively anatomically constrained increases. These expanded endonasal approaches can carry risks of cavernous carotid injury of up to 5–9%. This study examines methods to expand the surgeon’s armamentarium when dealing with these potentially catastrophic bleeds.

Aim: To demonstrate efficacy, ease of application and safety of a fibrin/thrombin patch (TachoSil [Baxter]) and fibrin/thrombin glue (Evicel [Johnson & Johnson]) combined with oxidized cellulose (Surgicel snow [Johnson & Johnson]) in the acute management of major vessel hemorrhage in endoscopic skull base surgery using an endoscopic model of carotid artery bleeding in sheep, and compare these with muscle patch and anastoclip controls.

Methods: Twelve merino sheep underwent neck dissection and application of an endoscopic trainer over the carotid artery. Standardized 4-mm linear incisions were made in the artery and the experimental patches used to control the hemorrhage with a 2 surgeon endoscopic technique. Hemodynamic changes, time to hemostasis and volume loss were measured. Animals were recovered for 3 months and underwent MRI angiography to determine incidence of pseudoaneurysm formation. Histology and electron microscopy of the site of injury was then performed.

Results: Fibrin/thrombin patch was able to control hemorrhage with no animals exsanguinating and mean time to hemostasis of 124 seconds. Fibrin/thrombin glue and Surgicel snow controlled hemorrhage with mean time to hemostasis of 79.8 seconds. Mean blood volume loss was 281 mL in the fibrin/thrombin patch group and 150 ml in the fibrin/thrombin glue group. Mean arterial blood pressure at commencement was 67.7 mm Hg in the patch group and 69.8 mm Hg in the glue group. Mean arterial blood pressure at hemostasis was 64.3 mm Hg in the patch group and 62.5 mm Hg in the glue group. One animal in the patch group died day 11 postoperatively from rupture of a histologically confirmed pseudoaneurysm. Historical muscle patch controls from our group showed mean time to hemostasis of 928 seconds and mean volume loss 850 mL. Historical controls using anastoclip had mean time to hemostasis of 146 seconds and mean volume loss of 249 mL.

Conclusion: Fibrin/thrombin patch and fibrin/thrombin glue with oxidized cellulose are potentially valuable adjuncts to the control of major vessel hemorrhage in endoscopic surgery. They are able to be introduced and manipulated trans-nasally with endoscopic instruments, result in significantly lower time to hemostasis, less blood loss, and potentially have a lower rate of pseudoaneurysm formation than muscle patch. They also have the advantage of being immediately available and do not require harvesting by a second surgeon.