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| Abominal Aortic Tourniquet AAT™ |
The Abdominal Aortic Tourniquet - AAT™Hemorrhage Stops Here™
The Abdominal Aortic Tourniquet is the first device to provide stable and complete occlusion of flow of blood to the lower extremities. It has 510(k) approval from the FDA for difficult to control inguinal hemorrhage. It is applied to the mid-abdomen, tightened and inflated and may remain on for up to an hour safely.
Available Mid-April 2012
The Abdominal Aortic Tourniquet is the first device to provide stable and complete occlusion of flow of blood to the lower extremities. It has 510(k) approval from the FDA for difficult to control inguinal hemorrhage. It is applied to the mid-abdomen, tightened and inflated and may remain on for up to an hour safely.
Available Mid-April 2012
Abdominal Aortic Tourniquet – AAT™
The project is focused at the number one priority identified by the Institute of Surgical Research for care on the battlefield: how to address uncompressible hemorrhage that is not treatable by a tourniquet in the leg, groin and inguinal region. This encompasses a significant capability gap related to preventable deaths. The solution to this problem must be stable, easy to apply and completely stop the loss of blood. The AAT™ is capable of this, and animal and human studies have demonstrated its safety and efficacy.
The AAT™ provides a rapid application of pneumatic compression to the aorta at the abdominal-pelvic junction to occlude blood flow in the inguinal arteries. The specific claim of the device is to occlude arterial flow through the inguinal region. The target of the compression is the aortic bifurcation, which has historically been identified in relation to the umbilicus or the superior margin of the iliac crests. Difficult bleeds in the inguinal region continue to be a significant source of morbidity and mortality on the battlefield. Providing solutions for treating these wounds have direct life saving results. Wounds to the pelvis and inguinal region are now preventable causes of death.
The AAT™ is a circumferential device that greatly increases the stability of the compression. The pneumatic wedge shaped bladder provides focused pressure to squeeze the blood vessels passing through the lower abdomen and preventing flow. The research referenced below demonstrates the safety of up to one hour of application and its effectiveness in non-invasively cross-clamping the aorta or fully stopping all blood flow to the pelvis and lower extremities. In essence the AAT™ acts as a valve to figuratively ‘turn the faucet off’ and prevent the further flow of blood out of wounds below its application site.
Blood is the vital component to surviving blunt or penetrating trauma in the golden hour. It allows oxygen to be carried to the heart, brain and kidneys. Every drop of blood lost impacts survival. Why let any of it spill to the ground when we can prevent its loss?
Research
Georgia Health Sciences University (formerly the Medical College of Georgia) has conducted research on the device using a swine model in 2009. Flow was undetectable in the femoral catheter during the tourniquet application. For hemodynamic variables, there were no significant differences in MAP or CVP measurements among animals. However, using one way repeated measures analysis of variance, there was a significant difference in MAP (P = 0.008) between 0 and 55 minutes for each subject. Serum potassium did not reach clinically significant numbers. However, serum lactate was significantly different between times 55 minutes (3.6 mmol/L +/- .95) and after tourniquet release 65 minutes 5.9 mmol/L +/- .87) (p <0.001). Gross and histological examination revealed no signs of significant ischemia or necrosis of the small and large intestine. These data were presented at the Advanced Technology Applications for Combat Casualty Care conference in August 2009 and the American College of Emergency Physicians Scientific Assembly in 2009.
Application of the device was studied on humans in 2011 again at the Georgia Health Sciences University and found to be safe and effective during the protocol. The Common Femoral Artery (CFA) was reduced to a no flow state by applying an average of 191 mm Hg. The device was associated with moderate discomfort that resolved completely with device removal. These data were presented at the Advanced Technology Applications for Combat Casualty Care conference in August 2011.
FDA Approval
Compression Works received FDA approval for the AAT™ on October 22, 2011.
The project is focused at the number one priority identified by the Institute of Surgical Research for care on the battlefield: how to address uncompressible hemorrhage that is not treatable by a tourniquet in the leg, groin and inguinal region. This encompasses a significant capability gap related to preventable deaths. The solution to this problem must be stable, easy to apply and completely stop the loss of blood. The AAT™ is capable of this, and animal and human studies have demonstrated its safety and efficacy.
The AAT™ provides a rapid application of pneumatic compression to the aorta at the abdominal-pelvic junction to occlude blood flow in the inguinal arteries. The specific claim of the device is to occlude arterial flow through the inguinal region. The target of the compression is the aortic bifurcation, which has historically been identified in relation to the umbilicus or the superior margin of the iliac crests. Difficult bleeds in the inguinal region continue to be a significant source of morbidity and mortality on the battlefield. Providing solutions for treating these wounds have direct life saving results. Wounds to the pelvis and inguinal region are now preventable causes of death.
The AAT™ is a circumferential device that greatly increases the stability of the compression. The pneumatic wedge shaped bladder provides focused pressure to squeeze the blood vessels passing through the lower abdomen and preventing flow. The research referenced below demonstrates the safety of up to one hour of application and its effectiveness in non-invasively cross-clamping the aorta or fully stopping all blood flow to the pelvis and lower extremities. In essence the AAT™ acts as a valve to figuratively ‘turn the faucet off’ and prevent the further flow of blood out of wounds below its application site.
Blood is the vital component to surviving blunt or penetrating trauma in the golden hour. It allows oxygen to be carried to the heart, brain and kidneys. Every drop of blood lost impacts survival. Why let any of it spill to the ground when we can prevent its loss?
Research
Georgia Health Sciences University (formerly the Medical College of Georgia) has conducted research on the device using a swine model in 2009. Flow was undetectable in the femoral catheter during the tourniquet application. For hemodynamic variables, there were no significant differences in MAP or CVP measurements among animals. However, using one way repeated measures analysis of variance, there was a significant difference in MAP (P = 0.008) between 0 and 55 minutes for each subject. Serum potassium did not reach clinically significant numbers. However, serum lactate was significantly different between times 55 minutes (3.6 mmol/L +/- .95) and after tourniquet release 65 minutes 5.9 mmol/L +/- .87) (p <0.001). Gross and histological examination revealed no signs of significant ischemia or necrosis of the small and large intestine. These data were presented at the Advanced Technology Applications for Combat Casualty Care conference in August 2009 and the American College of Emergency Physicians Scientific Assembly in 2009.
Application of the device was studied on humans in 2011 again at the Georgia Health Sciences University and found to be safe and effective during the protocol. The Common Femoral Artery (CFA) was reduced to a no flow state by applying an average of 191 mm Hg. The device was associated with moderate discomfort that resolved completely with device removal. These data were presented at the Advanced Technology Applications for Combat Casualty Care conference in August 2011.
FDA Approval
Compression Works received FDA approval for the AAT™ on October 22, 2011.
“There is no way to put a tourniquet around it, so soldiers are getting shot
in this area and dying within several minutes,” said Dr. Richard Schwartz,
Chairman of the Department of Emergency Medicine in the Medical College of
Georgia at Georgia Health Sciences University. Police officers wearing chest
protection as well as automobile accident victims can sustain similar
injuries.Efforts to externally compress the injury have been largely ineffective; the inch-round aorta runs parallel to the spine, so it can’t be approached from the back, and is several inches inside the abdomen even in a fit soldier.
Schwartz and Dr. John Croushorn, Chairman of the Department of Emergency Medicine at Trinity Medical Center in Birmingham, Ala., hope their inflatable wedge-shaped bladder will make a lifesaving difference.
Abdominal Aortic Tourniquet
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| Abominal Aortic Tourniquet AAT™ |
“By effectively cross-clamping the aorta with the abdominal aortic tourniquet, you are essentially turning the faucet off,” Croushorn said. “You are stopping the loss of blood from the broken and damaged blood vessels. You are buying the patient an additional hour of survival time based on blood loss.”
It was known that the knee pressed into the mid-abdomen could slow bleeding and block blood flow to the legs. The idea for the device came from studies conducted at GHSU in 2006 that quantified pressure needed to occlude the abdominal aorta. Schwartz and Croushorn started talking about turning that concept into a lifesaving device at an American College of Emergency Physicians meeting.
They first put the device on pigs, inflated it to the point there was no blood flow from the aorta to the femoral arteries and left it that way for an hour. There saw no potentially deadly increase in potassium levels in the blood and the pigs’ leg and gut tissue remained healthy. Next they used it on healthy humans for a shorter duration to ensure that the aorta could be completed occluded.
Croushorn and Schwartz have premarket clearance for the abdominal aortic tourniquet from the Food and Drug Administration and have identified a manufacturer. They already have orders for the device from the U.S. military and will teach courses on how to use it to the military and law enforcement. Device development was funded by the U.S. Department of Defense.
The physicians still want to explore their device’s potential for also helping CPR recipients. The chest compression that is the hallmark of CPR actually pushes blood all the way out to the extremities when the focus is keeping vital organs alive.
“With this device, you could, in theory, double the blood flow to the kidneys, heart and brain,” Schwartz said. They also believe it will help concentrate drugs given during CPR where they are needed. “Now when a medic pushes a cardiac drug during cardiac arrest, the drug is circulated through the toes before it reaches steady state concentrations in the heart,” Croushorn said.
Schwartz was a member of the 5th Special Forces Group (Airborne) during Operation Desert Shield and Desert Storm. He works with the Federal and Georgia Bureaus of Investigation and helped develop courses that bridge the gap between military and civilian groups that may work together during major disasters. Croushorn served as Command Surgeon, Task Force 185 Aviation in the U.S. Army in Iraq in 2004. He also works with the FBI.
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