How I Do It: Utilization of High-Pressure Sealants in Aortic Reconstruction

Increased blood loss during aortic reconstructive surgery can arise from friable, thin tissue in aneurysms, connective tissues, dissected aortic tissues, and holes/tracks left by large needles. The instability of the patient’s hemostasis is also affected by intraoperative anticoagulation therapy. If hemostasis is not secured, increased blood loss and need for blood products, increased operative time, and reoperation may ensue. The development of high-pressure sealants helps alleviate the perioperative challenges in treating patients with aortic pathology. Elefteriades describes his use of two high-pressure sealants for these procedures. The first is polyethylene glycol (PEG) that provides an adherent, almost clear gel-like clot at the point of application; coagulation mechanisms are not involved at all. PEG can be applied with either a spray device that needs a separate pump or a self-contained standard applicator. The polymers gel within 5 s and set in 60 s. The flexible, clear, degradable gel seals and adheres to tissues, even irregular and anastomotic structures. It keeps a tight seal despite high pressures in vessels such as the aorta. The second material is bovine serum albumin-glutaraldehyde (BSAG) glue, with adhesive and sealant properties and available in a self-contained applicator. It polymerizes in 20-30 s and attains bonding strength in 2 min. It is appropriate for repairing dissected aortic layers and reinforcing fragile aortic tissues. Adverse events include phrenic nerve damage causing diaphragmatic paralysis, false aneurysm, and complications from embolized particles released into the vessel lumen. PEG sealant swells to four times its initial volume within 24 h of application so it becomes a mechanical barrier to cellular infiltration while the inflammation subsides. Because PEG and BSAG cause a chemical reaction between the product and tissue surface, a reaction to the foreign material is to be expected. The degree of response depends on the implantation site, reactivity of the patient, and type and amount of product used. The resorption rate of PEG is rapid, within 30 d of implantation. BSAG degrades by proteolysis and is resorbed slowly, being found 1 y after implantation in a goat model. The author describes general application techniques along with techniques for reconstruction of the ascending aorta and aortic arch replacement. In a retrospective review of 60 major thoracic aortic operations in 57 patients, PEG sealant was used for aortic valve replacement/aortoplasty, root-sparing ascending aorta, composite ascending aorta, root-sparing ascending aorta/hemiarch, composite ascending aorta/arch, and descending aorta/reconstruction. The most common surgeries were aortic valve replacement/aortoplasty in 10 patients and composite ascending aorta in 17. Comparisons with other agents were not done, but bleeding results were favorable for these operations. Topical hemostatic application of PEG sealant to the suture lines can help prevent bleeding, particularly now that aprotinin is no longer available. The high-pressure surgical sealants are a critical adjunct and offer significant advantages.