New Products on Horizon for Prehospital Hemorrhage
By Damian McNamara
Elsevier Global Medical News
CHICAGO -- Research on how to stop or minimize bleeding in patients en route to the hospital is expected to yield strategies in the near future that will improve upon existing products, according to Dr. George Velmahos.
Exsanguination plays a role in more than 50% of trauma deaths, and because current products are "fundamentally flawed," there is still an unmet need for preventing deaths prior to patients' arrival at the hospital, Dr. Velmahos said at the annual clinical congress of the American College of Surgeons.
"People are more likely to die from excessive blood loss in rural areas, during battle, and even just a few minutes away from a trauma center," Dr. Velmahos explained.
A portable abdominal insufflator that could minimize bleeding through maintenance of internal pressure is more promising than current topical wound products such as Quikclot Zeolite or HemCon Chitosan dressings, said Dr. Velmahos, chief of the division of trauma, emergency surgery, and surgical critical care at Massachusetts General Hospital and professor of surgery at Harvard Medical School, both in Boston.
He became interested in prehospital use of insufflation after experiencing difficulty with bleeding during the early years of laparoscopic surgery.
For example, when a laparoscopic gallbladder procedure failed and had to be converted to open surgery, it took 10-15 minutes to stop internal bleeding. Dr. Velmahos realized that abdominal insufflation could keep blood loss in check.
Multiple animal studies support the use of insufflation, including work by Dr. Velmahos and his colleagues demonstrating 61% less blood loss in pigs that were insufflated during surgery (J. Trauma 2003;54:590-4).
The Massachusetts Institute of Technology is developing a portable abdominal insufflator for the prehospital setting. The device is smaller than a laptop computer, Dr. Velmahos said.
"My hope in the next 5 years is [for] an insufflator that can fit in the pocket of an [emergency medical technician]," he noted.
A product that combines an expandable, hemostatic polymer with a superabsorbent core also appears promising. These devices look like tea bags of different sizes and self-expand when they come into contact with blood, Dr. Velmahos said. In another study, he and his colleagues found that the technology reduced blood loss in a study of pigs with exsanguinating extremity injuries (J. Trauma. 2009;66:984-8).
There are tradeoffs to many of the current products, Dr. Velmahos said.
Quikclot is a granular zeolite product that dehydrates blood (Z-Medica Corp.). But it is an off-the-shelf product with no need for preparation, and zeolite has improved survival in animal studies in a laboratory setting by almost 100%, Dr. Velmahos said.
"There are mixed results, however, in civilian practice," he cautioned. "There were anecdotal reports of zeolite working in the Navy and Army. I had some injuries where the bleeding did not stop," he noted.
Chitosan dressings (HemCon Bandage, HemCon Medical Technologies) are designed to promote clotting. Although there are no burns associated with their use, these dressings are expensive and have some geometric limitations with getting them into wounds, he said.
"We can save lives if we push our ability to control bleeding in the prehospital scenario, whether it's internal bleeding or proximal external bleeding," Dr. Velmahos said.
Dr. Velmahos said that he had no relevant disclosures.