UPDATE ON THE ABDOMINAL AORTIC TOURNIQUET

iPhoneIcon_BigAbdominal aortic tourniquets have been around as an idea for a hundred years but still haven’t been accepted as mainstream trauma care. A small study on volunteers in military medicine tests one of these devices. They seem to work.

Background
AATIEDs caused the majority of losses in the wars in Iraq and Afghanistan. While there have been advances in helmet and body armour design, the lower limbs, groin and pelvis remain relatively exposed.

Consequently injuries in the lower limbs and pelvis have become more common. Haemorrhage from junctional parts, the pelvis and the groin have emerged as leading killers.

This is why designs like the Abdominal Aortic Tourniquet has received attention from military docs and medics.

It is designed to compress the aorta at the level of the umbilicus thereby preventing infraumbilical blood flow and hopefully buying the time the victim needs to get to definite treatment.

In the image to the right the AAT is mounted on top of a standard pelvic binder demonstrating how they don’t interfere with each other. The AAT is basically a girdle with a windlass and then an inflatable balloon.

The study
The study was conducted by the UK Royal Army Medical Corps. 16 healthy, young serving soldiers volunteered for the study. The AAT was applied and then inflated  until femoral blood flow stopped according to doppler ultrasound or until a maximum pressure limit of 300 mmHg was reached.

Results
Femoral blood flow ceased completely in 15 of the 16 volunteers. In one subject it didn’t work as intended. That volunteer had a height, weight, girth and BMI greater than average. He also reported a pain score that was higher than the average. The authors speculate that abdominal wall tension, due to the volunteer being uncomfortable, could have contributed to failure. The authors also speculate that this would be less of an issue in anesthesised, shocked or unconscious patients.

Take-home message
This is data suggesting the abdominal tourniquet principle is useful. For me, this is relevant in pelvic trauma, untourniquetable lower limb bleeds or in gyn/obs bleeds. Traditionally, external aortic compression is achieved by putting a knee or fist in the groin with all your body-weight on it. A made-for device could do this job better (especially in prehospital care or retrieval). I am surprised these devices haven´t entered the mainstream yet.

The evaluation of an abdominal aortic tourniquet for the control of pelvic and lower limb hemorrhage. Taylor DM, Coleman M, Parker PJ. Mil Med. 2013;178(11):1196-201. doi: 10.7205/MILMED-D-13-00223.

 
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10 Responses to UPDATE ON THE ABDOMINAL AORTIC TOURNIQUET

  1. Scott says:

    One thing competing with this device in the in-hospital environment is the sexiness of REBOA. But as you say, I see this as a perfect prehospital device and a transition in the ED until REBOA can be applied (keep it on until you have your sheath in the femoral (which would obviously need to be placed via ultrasound).

  2. …and even the obstetricians could use it, as an adjunct in catastrophic PPH

  3. Oliver Hawksby says:

    The authors do voice a concern about the use of these devices in older, more atherosclerotic aortas and how they might function then, but for young populations seems a good idea.

  4. Good day,
    Speer Operational Technologies is the master distributer in the US for the Item recently renamed the Abdominal Aortic and Junctional Tourniquet (AAJT). The renaming was due to recent clearances granted to the AAJT by the FDA. These are listed below. If you have additional questions or would like some additional information, please send us a note at Info@speeroptech.com.
    Thank you
    Chris

    FDA Clears a new 510(k)! The AAT is now the AAJT, the Abdominal Aortic and Junctional Tourniquet… its not just for the abdomen anymore!

    The new FDA clearance provides for the following changes:
    - The AAJT is now the only device to carry an indication for Pelvic bleeding
    - The AAJT is cleared for use in the groin and axilla for 4 hours
    - the hard time limit for the abdomen has been removed, it should be left in place until directed by a physician to be removed.
    - there is no longer any contraindication for penetrating abdominal trauma.

    The AAJT remains the only Class II medical device cleared for junctional hemorrhage. It is in use in almost a dozen countries around the world. It is still the only junctional device with human studies to show its efficacy and safety. And it is the only device to have saved lives in both upper and lower junctional hemorrhage.

    Chris Crossley
    Speer Operational Technologies
    Military Program Manager

  5. Another life saved. April 5th, 2014
    This time it is on a gun shot victim and a left groin application of the Abdominal Aortic and Junctional Tourniquet (AAJT).
    Heart rate 150 bpm, no felt pulse and unobtainable blood pressure. The diaphoretic patient was shot three times, twice in the right leg and once in the left leg. Neither of the wounds in the right leg were bleeding. The wounds in the left leg reflected an entry in the high lateral thigh and exit in the proximal inner thigh with a large amount of blood still coming out of the hole in the inner thigh. A CAT tourniquet was placed above the wounds on the proximal left leg and tightened and the blood flow stopped. The patient was quickly given 2 units of emergency release blood and a liter of saline. His systolic blood pressure came up to a detectable 75 mm Hg. And his heart rate began to drop but only to 130 bpm. At this point the wound began bleeding again. There was no room to fit another CAT tourniquet above the first so a junctional tourniquet was used. The patient was now more alert asking to have the CAT removed. The AAJT was placed in the left inguinal region, secured, tightened and inflated. No further bleeding was noted from the wound. The CAT was not removed but was loosened. The patient reported that the AAJT was far more comfortable than the CAT. We arranged transport to a local level one trauma center. Prior to transport he received two additional units of emergency release blood and an additional liter of saline. He was completely alert and oriented, his pulse now down to 108 and his systolic blood pressure up to 112. He arrived at the trauma center without having to have the AAJT adjusted or further inflated. He went to surgery, survived and walked out of the hospital on postoperative day 3.

    • Thomas D says:

      Hi Chris,

      Thanks for the case report. Great save! I can almost feel the stressed thrill of the team saving him! Please let us know if/when this is published as a case report in a medical journal.

      Can I ask if this was a military or civilian trauma? Sounds like this would be a difficult, or even impossible, save without the use of tourniquets.

      Interesting to note that the AAJT was more comfortable than a traditional tourniquet. Not paramount when life’s at stake, but surely helps both the patient and the resus situation if the patient is in less pain.

      Just a few points for the sake of discussion: As a general rule, trauma management in massive hemorrhage relies on giving blood and blood products and avoiding clear fluids. But that’s not always possible in practical handling of patients. Also, keeping patients in permissive hypotension is often a goal to shoot for – but as the bleeding is (for all practical purposes) stopped by the AAJT, I guess closer to normotension is good. All this mentioned for the sake of discussion, and with the use of the awesome rectrospectoscope.

      Having said that, like I mentioned, a great save! Good job by the team! This is the type of patient that could easily and quickly bleed to death, or spend too long in the OR of a non-trauma hospital trying to stop the bleed.

      I also greatly appreciate you commenting with full disclosure of your ties to the AAJT. Transparency like that isn’t always followed, but is surely the way to go! Thanks!

      • I write frequently about Junctional Hemorrhage, but what is it?

        What is Junctional Hemorrhage?

        Junctional hemorrhage, bleeding from the areas at the junction of the trunk and its appendages, is a difficult problem in trauma. These areas are not amenable to extremity tourniquets because the area that is bleeding will not allow placement that can create circumferential pressure around the extremity and above the wound. Junctional arterial injuries can rapidly lead to death by exsanguination prior to care in the hospital so out-of-hospital control of junctional bleeding can be lifesaving.1

        For the study interval between October 2001 and June 2011, 4,596 battlefield fatalities were reviewed and analyzed. The stratification of mortality demonstrated that 87.3% of all injury mortality occurred pre-Military Treatment Facility (MTF). Of the pre-MTF deaths, 75.7% (n = 3,040) were classified as non-survivable, and 24.3% (n = 976) were deemed potentially survivable (PS). In this study the injury/physiologic focus of PS mortal wounding was largely associated with hemorrhage (90.9%) and the primary site of lethal hemorrhage was truncal (67.3%), followed by junctional (19.2%), and then peripheral-extremity (13.5%) hemorrhage.2

        From the statistics cited above we can deduce that there were 976 PS patients, with 91% of those involving hemorrhage. This results in a total of 888 PS patients that died as a result of hemorrhage. From these hemorrhagic cases we find that 19.2% involved junctional hemorrhage resulting in a potentially survivable subgroup of 171 patients from this study. Therefore, if a device that can control junctional hemorrhage had been available, 171 persons with life threatening hemorrhage from junctional regions could have been treated near the point of injury most probably resulting in reduced mortality in this subgroup. And if that junctional device were multi-site capable so it could also be used to control extremity hemorrhage if needed then perhaps more in the peripheral-extremity sub-group could have survived. Additionally it is unclear to what extent that the authors of this study categorized inter-pelvic bleeding, a common component of both amputations from blast and from blunt trauma like motor vehicle accidents, as truncal hemorrhage. However it is very clear that if a device were capable of controlling not only junctional hemorrhage but was also clearly indicated and effective for controlling inter-pelvic hemorrhage, it could potentially change which injuries are viewed as “potentially survivable” in this study and thereby further expand survivability.

        Fortunately there is such a device and it is currently in use in both military and civilian pre-hospital and hospital environments. The device to which I am referring is the Abdominal Aortic and Junctional Tourniquet (AAJT TM), previously known as the Abdominal Aortic Tourniquet (AAT TM). The AATTM was selected as one of the Popular Science Magazine “Top Ten Inventions for 2012” and is capable of shutting off all blood flow to the lower extremities when it is applied to the mid abdomen. When applied in the abdominal placement area (easily identified by the belly button) the strap is pulled snug and the windlass is turned to remove any remaining slack. Then the hand pump is used to inflate a wedge-shaped bladder until the pressure gauge reads green at approximately 250mm Hg. At this point the wedge is creating a pressure bar that is compressing the aorta against the spine and shutting off all blood flow to the pelvis and both lower extremities.3 This keeps oxygenated blood circulating in the core and insures perfusion of the vital organs and the brain until surgical repair to the damaged vessels can be made.

        The AAJTTM is also unique because it has actually saved lives in all three junctional hemorrhage placement areas. These placement areas are the axilla (left or right), the inguinal crease/groin (left or right), and the mid-abdomen. The following is excerpt is from the Summer Edition of the JSOM, May 2013:

        “The Abdominal Aortic TourniquetTM was used recently in Afghanistan to control severe hemorrhage in a casualty who had traumatic bilateral amputations of the lower extremities. A medical provider in charge of the evacuation of the casualty was given access to an AAT and followed the packaged instructions for use in applying it. There was minimal respiratory effort with only small CO2 complexes showing on the monitor. The casualty had no palpable carotid pulse. Current generation Combat Application Tourniquets (CATs) were placed around both thighs; his lower legs were mangled, and there was a pool of bright red blood on the stretcher between his knees. Despite continued transfusion, given the lack of a carotid pulse and a catastrophically low EtCO2, the AAT was placed using the log roll as an opportunity to do this- The AAT was inflated; in doing so, the ETCO2 rose immediately…and the patient had a carotid pulse on arrival. The patient required no sedation, and care was transferred to the trauma team. The AAT was transitioned in the operating room for surgical hemorrhage control, and the patient survived. The patient underwent a through-the-knee amputation on one leg and an above-the-knee amputation on the other leg.”4

        In June 2013 the AAT was also successfully applied to the axilla in order to control hemorrhage caused by a bullet severing the brachial artery in a 41-year-old male in Birmingham, Alabama. This case reports says that the AAT was placed against the upper chest wall in the axilla and the belt was secured around the patient’s opposite shoulder. The patient was transported to the operating room wearing the AAT and the axillary artery was encircled with vascular tape and tightened to control hemorrhage after the AAT was removed. A vascular repair was done using an 8 cm section of the Saphenous vein and three days post surgery the patient was extubated, moving his hand on the side of injury, and following commands.5

        In April 2014 the AAJT was applied around the hips with the bladder against the left groin to control hemorrhage caused by gunshot wounds. The patient was shot three times: twice in the right leg and once in the left leg. The patient presented with a thready carotid pulse, tachycardia, and an unobtainable blood pressure. Neither wound in the right leg was actively bleeding upon examination. The wounds in the left leg reflected an entry in the high lateral thigh and exit in the proximal inner thigh with a large amount of blood still coming out of the hole in the inner thigh. An extremity tourniquet (ET) was placed high on the left thigh but the bleeding continued. Since there was no additional room on the thigh for the placement of an additional ET, the AAJT was placed in the left inguinal region, secured around the waist, tightened and inflated to 250mm Hg. Upon inflation of the AAJT no further bleeding was noted from the wound. The tension supplied by the ET was then removed by releasing the windlass but it was not removed from around the patients’ leg. The patient reported that the AAJT was far more comfortable than the ET had been when it was tightened. After surgical evaluation the patient was deemed stable enough to transfer to a local Level 1 trauma center and the AAJT prevented further blood loss and remained inflated throughout the transport without adjustment. Surgery revealed transection of the left deep femoral artery and it was ligated; the patient survived and walked out of the hospital on post-operative day three.6

        The AAJT has clearly demonstrated that it is capable of increasing a patients’ chance of survival from upper and lower junctional hemorrhage with successful applications in all three placement sites. Additionally, the safety and efficacy of the AAJT is well established through independent human research studies that are available at http://www.compressionworks.net/.

        For additional information about the AAJT, please email us at Info@speeroptech.com .

        References:

        1. http://www.ncbi.nlm.nih.gov/pubmed/24048982
        2. http://cdn.shopify.com/s/files/1/0227/4639/files/Eastridge_Death_on_the_Battlefield_J_Trauma_2012.pdf
        3. http://www.popsci.com/diy/article/2012-05/inflatable-tourniquet-stops-abdominal-bleeding
        4. http://www.compressionworks.net/resources/AAT-JSOM_SUMMER13.pdf
        5. http://www.compressionworks.net/resources/AAT-JSOM_FALL13.pdf
        6. Compression Works Face Book page: https://www.facebook.com/compressionworks?fref=ts

  6. Thomas,
    Thank you for the feedback.
    It was a civilian victim. I do not know the exact circumstances of the shooting.
    I am currently working on getting the case report from the attending physician and as soon as I receive that, I will provide you the information.

    Thank you again sir.
    Chris

  7. The AAJT Stabilizes the Pelvis!
    1 May 2014 – The FDA recognized that the “Inguinal Placement provides for pressure over the hips and pelvis allowing for pelvis stabilization in the event that the pelvis is broken.”
    The Instructions for use included in the packaging has been updated.

  8. vincent carlier says:

    Being a medic in the Belgian Army i would like to purchase the AAJT. My people will be sent shortly to the Central Africain Republic. Where can i purchase it?

    Thank you

    Vincent Carlier

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