We often get questions regarding hemostaics:
Which is the best?
How do they work?
What is the mechanism of action?
The TCCC recommendation of Combat Gauze (TM) has clouded the issue of effectiveness with respect to other available agents. That is to say, there are others on the market that were just as effective in studies that were not chosen. Hopefully, the attached study summarizes the pros and cons of most available agents.
Below is an excerpt from a lessons learned compilation titled “First to Cut: Trauma Lessons Learned in the Combat Zone.” Though it is geared toward FST surgeons and forward medical providers, some of the lessons are applicable to tactical medics and mountain rescue. The larger take-away point is that the physiology occurring distally to a tourniquet applied for a long duration needs to be considered when changing or loosening, especially in environments where medical care may be limited (e.g., Third World).
“26 y.o. male with foot traumatic amputation and
multiple frag wounds to the right leg with a high thigh
field tourniquet in place. Arrived to the CSH with SBP of
100 HR of 120. we had no report on duration of the
tourniquet. We took down the tourniquet and he promptly
coded. We put the tourniquet back up, intubated him and
gave him fluid and bicarb and he came back. We found
out later that the tourniquet had been in place for over 4
hours….”
The use of tourniquets – while rare in civilian trauma is
very common in combat injuries. Tourniquets are the
number 1 instrument that a medic can employ to lower the
KIA numbers. The use of tourniquet with application until
the absence of a distal pulse by default causes distal
ischemia. Release of a functioning tourniquet after several
hours can result in the release of acidic fluid and potassium.
The patient intubated and without a head injury can be
briefly hyperventilated. Before taking down a long
duration tourniquet make sure the patient is well hydrated,
resuscitated, adding an ampule of sodium bicarbonate or
THAM can prophylax against the release of “bad humors”,
lactic acid, and potassium. Also release the tourniquet
slowly – if the rare arrhythmia arises re–employ the
tourniquet and retry after further bicarb and fluid. If the leg
is necrotic remember “life before limb” and perform an
amputation.
Lessons Learned:
–Prolonged tourniquet times can result in the release
of acidotic fluid and hyperkalemia
–Perform 4 compartment fasciotomy with all lower
extremities with significant tourniquet times
Summary
This study was designed to identify the most effective underbody
position when using the patient’s own body weight as an
infusion device. Twenty volunteers had an air-less 500ml bag of
saline located at various under-body positions. Mean pressures
and flow rates through a 14G cannula were measured in vitro at
room temperature. Locating the fluid bag at the buttock cleft
delivered the highest mean flow rate at 135ml/min. This underbody position may provide flow rates sufficient to achieve the clinical aim of fluid resuscitation in the military pre-hospital
environment.
A dictum of tactical medicine is to carry equipment that has dual use. In the case of fluid infusion, medics are instructed to use their blood pressure cuffs or the patient if no other device is available. Medics have the option of carrying pre-made fluid infusers or an extra BP cuff, but the former violates the rule of dual use and the latter may be too bulky. The above article offers a valid, though not new, solution, because it explores the best location if a medic chooses to use the casualty.
Early use of anti-biotics in combat trauma is now commonplace amongst most military medical circles. The liberal use of antibiotics in a tactical or combat environment has spawned numerous products to ease the process. Some of the items are very useful while others have little suitability to the injuries associated with trauma created by high-velocity fragments or penetrating trauma.
Antibiotics currently recommended for administration in the tactical environment generally are in pill or injectable form and they function on a systemic level instead of a local level. When considering the depth of the injuries associated with combat, placing a bandage impregnated with an antibiotic on the surface of an injury is almost senseless. It will serve to minimize or eliminate microbial activity at the surface of the wound, but it does nothing for the majority of the injury.
The real danger is when this type of dressing is used as a substitute for administering antibiotics in the field. Topical antibiotic treatment of penetrating trauma is similar to attempting to drink water without opening your mouth. You will wet your lips, which might make you feel better, but does little to help hydrate the body. These dressings do serve a purpose, however. For lacerations, abrasions and burns they are a sensible solution, but you wouldn’t treat a gunshot wound with Bacitracin. Therefore, don’t rely on the same concept in a different form. Administration of systemic antibiotics is the current accepted standard for combat trauma. Don’t accept anything less if you have the choice.
Tourniquets are an effective means of arresting life-threatening
external haemorrhage from limb injury. Their use has not
previously been accepted practice for pre-hospital civilian
trauma care because of significant concerns regarding the
potential complications. However, in a few rare situations
tourniquet application will be necessary and life-saving. This
review explores the potential problems and mistrust of
tourniquet use; explains the reasons why civilian pre-hospital
tourniquet use may be necessary; defines the clear indications
for tourniquet use in external haemorrhage control; and
provides practical information on tourniquet application and
removal. Practitioners need to familiarise themselves with
commercial pre-hospital tourniquets and be prepared to use
one without irrational fear of complications in the appropriate
cases.
See Paper Here: TQs in Civilian Trauma Care
It is important to understand that science has not yet isolated the compounds essential in the production of fairy dust. Modern hemostatic agents require proper technique and training to function properly. Simply placing these products onto or into wounds does not solve all of your problems. If members of your organization are issued hemostatic agents, it is essential that they are trained on the agents and fully understand their limitations.
There are four steps you ought to follow when using hemostatic agents:
2) Identify the bleed. Placing or pouring an agent onto or into a wound without identifying the bleed is unwise. If you have a large cavity that requires hemostatic agent, you must make sure the agent is placed DIRECTLY ONTO THE damaged vessels in order for it to work. Otherwise, you are wasting blood cells and agent.
3) Proper placement. After identifying the bleed, you must ensure the agent is placed DIRECTLY ONTO THE BLEEDER. If you do not, you run the risk of creating a “crust” made of blood and agent above the vessels. In so doing, you have visibly stopped the bleeding by forming a large clot, but it has not stopped the bleed.
4) Pressure. Hemostatic agents do not relive you of the basics that are required for hemorrhage control. After using a hemostatic agent, you MUST place gauze behind it in order to create pressure, so as to allow a clot to form. Otherwise, you run the risk of the agent being washed away or of a “crust” forming and creating a hematoma. It is also necessary to use the gauze to hold the agent in place and prevent it from shifting during patient movement. A minor shift during movement can cause a re-bleed which could be fatal if overlooked during re-assessments
Considerations/limitations
The ability to pack a wound is an essential skill for the tactical medic. While a tourniquet is an excellent tool for controlling hemorrhage in extremity trauma, there are many areas that do not allow proper application of a tourniquet. The video on wound packing was produced to show the fundamentals of wound packing.
A. Identify the bleed-
It is essential that the medic identify the source of the serious hemorrhage. Simply stuffing gauze into a cavity is not always effective. Often times the pressure is not applied where it is needed and the gauze only acts as a sponge. What makes packing a wound effective is that is provides focused pressure directly on the damaged vessel. By occluding the lumen of the vessel with the gauze you get hemorrhage control. If it is not completely controlled it at least slows the hemorrhage to a point where the body’s natural clotting factors can interact with the gauze to form a clot. There are three main methods to identify the location of a bleed.
2. Tactile assessment
Feel works well if you are in a relatively calm mental state and have complete awareness of your senses. It is not a reliable source when you have been carrying heavy loads, firing weapons for long periods of time or participating in any activity that has caused your hands to fatigue. It’s also unreliable if you are wearing multiple layers of gloves.
3. Anatomy
A basic understanding of the vascular structure of the human body goes a long way in this situation. It isn’t as good of an indicator as visualizing the bleed, but if you are pressed for time it can be a good solution. It is best when used in conjunction with the other methods. It is also helpful when determining the best angle to pack from.
B. Pack into the Bleed
Notice what the section is titled, “Pack into the bleed”. It does not say pack into the wound. Your first few sections of gauze should go directly to the source of the major hemorrhage. After that hemorrhage has been staunched, the remaining gauze should be packed tightly around it to keep it in place. Your goal is NOT to create a sponge inside the wound, but a solid mass that applies pressure where it is needed. This is a very important point. An often-asked question is, “how much blood does the Olaes bandage absorb?” The answer is this: hopefully none. The purpose of bandages is not to absorb the most blood, it is to STOP bleeding, in order to keep blood where it needs to be: in the body. You don’t put bandages on to keep your vehicle clean.
C. Pack to the bone
The major vessels of the body are not inside muscular tissue! Most vessels run near the major bones in the body. If the wound is in a location that allows you to use the bone as a rigid object to maintain pressure on the damaged vessel, use it. Start by packing into the bleeder, and then use the gauze to squeeze the vessel between it and the bone. This creates the same effect as a vascular tourniquet, or simply holding pressure with your finger.
Educating medical directors and command surgeons in the importance of wound packing is essential. The ability to pack wounds is a necessary skill in an environment with the potential for delayed evacuation times and limited manpower. The idea that you will hold direct pressure for 3-5 minutes during a fire fight is ridiculous. Packing a wound reduces the need for this and frees the medic’s hands up to engage more important things, like the enemy. When used in conjunction with hemostatic agents, it is even more effective. We will cover how these two work together in a future entry.
With the increased use of tourniquets in tactical medicine, there is an active debate concerning the best location and proper method of storing a tourniquet on an individual’s equipment. While in the end it comes down to individual preference or unit SOP, there are some locations and methods that don’t make sense.
A tourniquet is an immediate lifesaving intervention and it should be treated similarly to a secondary firearm. Chances are your pistol is not carried in its original box packed away so you can claim a capability. It is positioned so the operator has access to it in seconds, under the most extreme circumstances. The same standards for accessibility and immediate operational use should be applied to your tourniquet. The time taken to implement this intervention should be kept to an absolute minimum. Storing a tourniquet in its plastic wrapper can be a fatal mistake. While it increases the service life of the product, it can create a situation in which the tourniquet cannot be accessed by the individual in need. The same situation can be created by storing the tourniquet inside a difficult-to-open, tightly-packed zippered pouch. While storing the tourniquet in a pouch attached to your equipment is advantageous if you are the victim of a large blast since it is far less likely to be torn from your gear, the disadvantages of this location (e.g., not being able to access it quickly) outweigh the advantages.
The best location for a tourniquet in a tactical environment is on the armor, along the midline of the operator’s body, unwrapped and pre-rigged for application. One technique is to secure the tourniquet with multiple rubber bands. The tourniquet can be accessed with either hand, is secured tightly to your individual equipment and is easily removed when needed. Furthermore, storing the tourniquet exposed rather than in a case or pouch provides the oft-needed visual stimulus for a rescuer or casualty to begin the act of tourniquet application. There is a lot to be said for having the answer staring you in the face when you look down or look at a casualty. The stress response to seeing a friend severely injured can often cause a brief period of inaction. Having the tourniquet readily available is one small step to combat this condition.
If your unit SOP is to carry tourniquets wrapped in plastic and stored tucked away inside of a pouch, you should seriously consider reevaluating the standard.
A tourniquet is a piece of live saving equipment. With that in mind, it is troubling to know that officers are either carrying tourniquets, or contemplating the purchasing of tourniquets, that are questionable with regard to effectiveness. What is more, they are making these decisions based on a questionable scientific study, most of which they did not completely read ( TQReport). It is not being hyperbolic to state that what it is arguing is a matter of life or death. If you question that, then please revisit the last blog entry.
One not wanting to read the entire study is understandable. It is 90 pages of dry, scientific writing. At first glance, the study is methodologically sound. It is constructed to test the effectiveness of tourniquets in an environment that simulates combat conditions. However, after one reads the study completely, there is one glaring deficiency. The study did not test which tourniquets achieved 100% occlusion. I Repeat: IT DID NOT TEST IF TOURNIQUETS ACHIEVED 100% OCCLUSION. That should be the FIRST criterion a tourniquet must meet to continue a study. While the ISR study (see below) tested tourniquets that could achieve 100% occlusion, the Navy study did not, so all other criteria are irrelevant. Instead, it tested how easy it was to apply an ineffective tourniquet. As the study states:
Applications to arms were performed one-handed, but use of both hands was allowed for applications to thighs. A maximum of 5 minutes was allowed to apply the tourniquet, after which time the trial was terminated as an “application failure.” Application of the tourniquet was successful if the subject vocally declared, “Tourniquet on” — indicating that he had reached a point just before continued tightening would produce unbearable pain and had secured the device — within 5 minutes of being handed the test tourniquet. Upon such a declaration, a double event mark was recorded to mark the end of the application time period. The subject was asked to remain still throughout the remainder of the procedure.
Although the above may not seem like an issue, it is. First, applying a tourniquet until one thinks he/she has achieved hemorrhage control is not how it works. One applies a tourniquet to stop bleeding. One must continue to apply pressure until the bleeding stops. It is as simple at that. Second, using pain as indicator to cease applying pressure is not a good indicator. Doing so requires one to extrapolate the findings of a conscious, non-traumatic subject and apply them to an injured patient that has experienced enough trauma to require catastrophic-hemorrhage control.
Savvy distributors and manufacturers of different tourniquets have begun using this study to tout the effectiveness of their product. Beware. They are doing so based on the age-old assumption that consumers will not take the time to read all 90 pages. For example, they are giving potential consumers a chart that gives you a snapshot of the test that enumerates the tourniquets from best to worst. Please read the studies for yourself and make an educated decision. There are two tourniquets approved for use by the Army’s Institute for Surgical Research (ISR) (ISR Tourniquet Study). Do not let the desire to carry a tourniquet that is small–and possibly ineffective–outweigh the need to achieve hemorrhage control. Furthermore, short transport times DO NOT compensate for an ineffective tourniquet that can INCREASE bleeding. Finally, rid yourself of the disturbingly-common attitude that you will not actually need one . If that is the case, save yourself both money and weight and just don’t carry one. However, read the below post before doing so.
If you have any comments, please email them to alan@tacmedsolutions.com
