Bleeding Complications during Surgery

Perioperative bleeding and leakage from the site of anastomosis frequently cause severe complications during and after surgery.

Especially cardiovascular surgery carries a high risk of perioperative bleeding.  In cardiac procedures severe bleeding occurs in around 7% of cases1. The current standard of care used to address these issues includes fibrin-based sealants as well as synthetic sealants. Both however lack certain characteristics, making them unsuitable in a great variety of surgical settings. Consequently, bleeding complications and leakage remain unaddressed problems.

A strong, fully synthetic, yet flexible and biodegradable sealant that works in a wet environment and exhibits the necessary properties is urgently needed. Potential application areas for such a sealant include:

  • stopping arterial and venous bleeding
  • aortic root replacement procedures
  • vascular reconstruction procedures
  • suture line sealing and
  • reinforcement in cardiovascular surgery.

Arterial and Venous Bleeding

Cardiovascular surgery carries a high risk of perioperative bleeding.  Severe bleeding occurs in around 7% of cardiac procedures.1

This significantly increases the risk of post-operative mortality2. In order to control bleeding and minimize the risk of mortality, blood transfusions and reoperations are used.  These procedures, however, are often costly and bear considerable risk3.

To address this medical need, surgical sealants are used to seal areas of leakage during or after the operation.  This prevents suture line bleeding as well as postoperative complications due to leakage of other bodily fluids.

Aortic Root Replacement

Aortic root replacement is the surgical treatment for aneurysms in the aortic root, the section of the aorta, which is attached to the heart.

The aortic root is replaced with a graft, which is generally sewn into place using sutures. Major risks of this procedure include perioperative bleeding complications, which could be addressed with the right sealant technology.

Vascular Reconstruction

Most vascular anastomoses are performed with sutures, which are technically challenging.

In addition to this, bleeding at the site of anastomosis and leakage from suture lines is a major complication and a significant cause of morbidity and death.

Vascular reconstruction procedures are one of the common surgical procedures accompanied by bleeding complications during and after surgery. Replacement of the damaged section of an artery or vein with a graft, may result in heavy bleeding from the suture line, as grafts, both synthetic or tissue grafts, are most commonly sutured to the tissue. Massive bleeding from the suture line may be prevented by using a tissue adhesive for reinforcement and protection.

Cardiac and Vascular Surgery

With 7.4 million cardiovascular operations per year in the U.S. alone, there is a high need for blood preservation by minimizing intra- and post-surgical bleeding.

A study has shown that of 103,829 patients in the U.S. undergoing cardiac surgery, 47.4% suffered from bleeding related consequences such as blood transfusion, bleeding events or re-operation to control bleeding. The incremental cost per hospitalization associated with these bleeding-related complications, adjusted for covariates, was $10,279 for patients undergoing cardiac surgery1.

Conventional procedures used to control bleeding include the use of Fibrin sealants and hemostats, which are indicated for cardiac, general, orthopedic and hepatic procedures.  Additionally, products containing bovine serum albumin and glutaraldehyde are available as well as Polyethylene Glycol (PEG)-based hydrogels. These currently used devices either incur the risk of infection (human and bovine plasma-derived products), do not provide for a strong seal, or are ineffective on a wet surface.  The currently used devices can lead to vessel intimal hyperplasia as a complication of a reconstruction procedure or trauma and foreign body reactions which in turn can cause stenosis, thrombosis, and pseudo-aneurysms as the most common complications.  Moreover, the ineffectiveness of many of the current solutions in a wet and/or high-pressure environment, limits their use, particularly in the event of a complication, where having a solution matters most.

[1] Shander: “Financial and clinical outcomes associated with surgical bleeding complications.” Surgery 2007, 142:S20-S25.
[2] Rady et al.: “Perioperative determinants of morbidity and mortality in elderly patients undergoing cardiac surgery.” Critical Care Medicine 1998, 26(2):225-235.
[3] Shander: “Financial and clinical outcomes associated with surgical bleeding complications.” Surgery 2007, 142:S20-S25.
[4] Stokes et al.: “Impact of bleeding-related complications and/or blood product transfusions on hospital costs in inpatient surgical patients.” BMC Health Services Research 2011, 11:135.