Decoding the proper triage sequence

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What’s the key to saving the most lives possible?

There were once two quarreling brothers who pulled their pistols on each other. One had a 9mm and the other had a .45 pistol. Their injuries left questions that I could not find answers in the medical literature. How did only one survive with a seemingly lethal wound to the mid-sternum and the other succumbed to a wound in the right mid axillary line, when both were shot in the thoracic cavity at the same distance? This started a decade long quest that led to Oct. 1, 2017, where the Menes Triage Method was put to the test in the triage of over 100 patients in minutes.


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With seconds to evaluate the gunshot wounds, precision was key to finely stratify patients that were all red tags under the legacy Mass Casualty System. The Menes Triage Method (MTM) consists of a list of eight factors used in primary triage.

Gunshots to the head, neck, torso and proximal extremity all qualify as red tags in any legitimate MCI triage system. However, in the surge of a mass casualty incident, this broad criterion can result in hundreds of red tags. If you chose to work on patient #75 in the salvageability-timeline, instead of the 74 more critical patients solely because #75 was the first red tag you came across, the 74 more critically injured would die in the process. Dozens will continue in a sequential order that is not predicted by any other legacy triage system. Decoding that sequence is the key to saving every life possible in the Golden Hour.

To decode this, you must separate the large group of legacy red tags into groups by their predicted time-until-death.


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Red – Patients that are dying now. This would include the legacy gray tags brought in by scoop-and-run.

Orange – The patients whose time-until-death is in the second 20 minutes of the Golden Hour, after the red tags.

Yellow – The subgroup of patients whose time-until-death is during the last 20 minutes of the Golden Hour.

This fine stratification of red, orange and yellow tags was the key to organizing the needles in the haystack and decoding the sequence of the salvageability timeline. It allowed four emergency physicians to survive the Golden Hour and successfully resuscitate the largest surge of critically injured victims in the largest penetrating mass casualty in recent American history.


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It is impossible to cover the details of each topic here so the following is an abbreviated explanation of these eight factors.

1.Skin Color 

Skin color is a visual indicator that can quickly identify cyanosis, anemia, or hypoperfusion. In penetrating trauma, this indicates a significant injury and a need for immediate resuscitation.

2.Mental Status

Decreased mental status is a visual indicator of hypoxia, hemorrhage, or CNS injury. In penetrating trauma, this indicates a significant injury and need for immediate resuscitation.

3.Pulse

Palpating a carotid pulse is the fastest way to estimate the blood pressure. A thready carotid pulse indicates hemorrhagic shock and need for immediate resuscitation.

Rule #1: If any 1 of these 3 factors exist in a Penetrating Mass Casualty Incident, the patient is a Red tag needing immediate resuscitation.

Rule #2 If any 1 of these 3 factors present later in an orange or yellow or even green tag, the patient is upgraded to a Red tag needing immediate resuscitation.

As emergency physicians, we learn how to visually identify sick patients. The first three factors are an efficient use of known medical physical exam findings obtained in seconds using two visual and one tactile physical exam finding. These factors can be easily identified by those with minimal to extensive medical expertise. In conjunction, these three factors rapidly identify red tags and can differentiate black tags (pulseless victims), without sacrificing gray tags (apneic with a pulse).

Applied Ballistics and Wound Estimation

Using the first three criteria, dying patients can be rapidly identified. What about the rest of the red tags that are going to die next in the Golden Hour? Who will be next to die?

We typically use imaging to give us information, then take an educated guess on that time period. In an MCI, that is impossible. Stratifying patients by imaging would result in numerous deaths as time used in imaging deducts time away from resuscitation.

The solution to the question of what is the time-until-death of a patient is found in factors 4-8 of the Menes Triage Method, under the Applied Ballistics and Wound Estimation (ABWE) section. This uses your sight to make the rapid judgment call. In ABWE, the penetrating object can be a knife, shrapnel or bullet, so the information here can be used widely for triaging a range of penetrating trauma.

4.Trajectory

As a bullet enters the body, the bullet leaves a permanent and temporary cavity in its wake. The trajectory of this cavity is normally found by imaging, a luxury in a MCI. Trajectory of the bullet is essential for estimating the linear path of the permanent and temporary cavities.

There were dozens of bodies from the weekend packed into the Wayne County Coroner’s office. coroner’s office. In the room was a detective from Detroit Police Homicide, the coroner and a newly minted ER resident. In seconds, the coroner immediately identified the gunshot wounds, left axillary, right flank above the hip in the first body. He pulled out a long wooden dowel and pushed it through the left axillary wound. Effortlessly it slid in an inferior angle and exited out of the GSW above the right hip. The homicide detective commented how the trajectory of the bullet matched the victim’s orientation to the shooter.

They continued discussions further on the caliber and distance, but my mind was so fascinated that this wooden skewer could tell someone the trajectory of a bullet, without any imaging. As the coroner made the Y-incision, the anatomy confirmed the coroner’s assertion of the trajectory. I knew it was unethical to place a wooden dowel through a GSW in a trauma bay, but the thought that within seconds, the coroner identified the bullet trajectory, without any imaging, amazed me. The Straight-line Theory and Minimum Bullet-to-hole Ratio were developed to replace the coroner’s wooden dowel to estimate trajectory.

Straight-line Theory(SLT) A single bullet enters the body, forms the permanent/temporary wound cavities, and then exits the body, forming two holes. When a patient presents with two holes, connect both holes with an imaginary dowel like a vector in geometry. This vector is the permanent cavity, and the elliptical volume surrounding this vector is the temporary cavity. Unfortunately, if there is only one wound, the trajectory can be a vector in any combination of the xyz planes.

Minimum Bullet-to-hole Ratio(MBHR) It’s hard to hit a moving object. MBHR is the concept that multiple gunshot wounds do not always mean multiple bullets entered the body. When a patient presents with multiple gunshot wounds, apply the Straight-line Theory. Then look to see if the other GSWs are along permanent cavity vector. If the other gunshots line up, MBHR states that one bullet accounts for all of the wounds along that vector, then the trajectory of the bullet is along that single vector.  If the wounds don’t line up, then more than one bullet entered the body.

An unstable drop-off gunshot patient presented with multiple gunshot wounds. There was a wound to the left flank inferior to the ribs, as well as horizontally through the left antecubital fossa. As I brought the left arm down to the side of the victim, MBHR showed that the three holes lined up, indicating 1 bullet. SLT showed that the vector of the bullet traveled through the left arm and into the left upper quadrant, and the vector was estimated to traverse the spleen. This was estimated prior to imaging and Trauma’s arrival. This was verified by the splenectomy and hemicolectomy that was performed by the trauma surgeon.

5.Caliber

Differences in bullet caliber covers many topics that cannot be covered in this limited space. Essentially, the bullet creates a football shaped injury that is along the path of the trajectory vector. The size and shape of the football is dependent on the caliber. Any anatomical structure within this football has the potential to be damaged. The closer it is to the permanent cavity, the more severe the damage.

6. High Flow vs. Low Flow

Flow of blood is dictated by blood pressure and vessel diameter. For example, the proximal Aorta (high pressure/wide diameter) will have a higher flow rate of blood compared to the Saphenous vein (low pressure/small diameter).

7.Large Leak vs. Small Leak 

Injury to the blood vessel is the true issue in penetrating trauma. The hole in the blood vessel determines the flow of blood loss. The size of this leak can be even more important than the rate of flow in the vessel. A complete femoral vein transection (large leak/low flow vessel) can cause more blood loss than a nick of the Aorta (small leak /high flow vessel). The idea of leaking is also applicable to highly vascular organs such as the kidney, spleen, liver, heart and lungs; with emphasis on the arterial organs.

8.Organs Injured 

In ATLS, Airway, Breathing, and Circulation is the order we address traumatic injuries. As we correct these, we correct the most lethal triad in penetrating trauma; Hypoxia, Hemorrhage and Shock. Injuries to the airway, lungs and heart need to be efficiently addressed. This is why these constitute red tags in any system. Large blood vessels and highly vascular organs (kidney, spleen, and liver) can lead to significant blood loss over time, so these are almost as important. The blood loss from these is dependent on the size of the leak, so injuries to these organs can present as red, orange or yellow tags as the rate of blood loss will influence the time-until-death.

menes triage diagram

The Triage System

How to tag patients using the Menes Triage Method.

Step 1: Red tags

Start by using the first three factors: Skin Color, Mental Status and Pulse. If any one factor is off, the patient is an automatic red tag. Applied Ballistics is not used to identify Red tags.

Step 2: Orange tags 

Use Applied Ballistics and Wound Estimation (ABWE). If the trajectory crosses the head, neck, the thoracic cavity or the large vessel window, but initially has an intact pulse, mental status and skin color; they were placed in the orange tag section. These patients have a high probability for decompensating next.

Step 3: Yellow tags 

Use Applied Ballistics and Wound Estimation (ABWE). If the trajectory crosses only the abdominal cavity (and misses the abdominal aortic window) or proximal extremity (bleeding controlled by tourniquet), and the patient initially has an intact pulse, mental status and skin color, they were placed in the yellow tag section. These patients are likely to decompensate after the orange tag patients.

Step 4: Green tags

All other penetrating injuries that do not qualify as red, orange or yellow tags.

It was a “Homie-drop-off” with a left upper quadrant (LUQ) GSW. I took the left side chest position, Dr. Patrick Flores was on the right. The primary survey showed no signs of airway injury, symmetrical breath sounds were noted by Bag-Valve-Mask, so I jumped right into circulation. As the rapid transfuser was being set up to receive the Massive Transfusion Protocol, Flores stated, “There’s a bullet here in the mid-axilla, right under the skin.”

I’d been practicing the Menes Triage Method (MTM) for years now, but in the trauma bay, as all of the eyes in the ER stared, the Straight-Line-Theory connected the LUQ GSW to this right mid-axillary, sub-cutaneous foreign body. The ballistics estimated that the football shaped injury hit the left lower lobe, hilum, great-vessels, and right upper lobe before stopping subcutaneously under Flores’ gloved hand.

To those observing, an ER doctor was making the preliminary left chest wall incision of an ED thoracotomy on a GSW to the LUQ of the abdomen. As I made my cuts through the left intercostal muscles, I kept thinking, “If there is no blood in this left chest, you will not have a leg to stand on in front of the ethics committee.”

With each intercostal cut towards the axilla, the initial trickle of blood soon became a deluge, as the patient’s blood emptied onto the bed. My right hand dove into the pool of blood as my index finger cross-clamped the aorta while simultaneously initiating internal cardiac massage with my left. With each squeeze, streams of blood came from the left hilum and great vessels. As I surveyed volumes of blood that exited the circulatory system, I surmised that the wounds were not survivable.

What started with wooden dowels in the coroner’s office, a fight between two brothers, and a LUQ GSW, climaxed Oct.1, 2017. Hundreds of gunshot victims unknowingly put their trust in a theory that you could visually estimate the trajectory of a gunshot, and from that, time-until-death. Visual triage quickly sorted a massive surge of penetrating trauma without using vital signs. The MTM would find the gray tags for a small team of resuscitologists and prevent the disorganization that is the plague of every previous mass casualty incident.

The Menes Triage Method is not an exact science. It does not replace the current diagnostic tools. It is a practical educated guess used to survive a catastrophic situation of a massive bolus of penetrating trauma. As you continue your practice, mentally rehearse the MTM after you have saved your penetrating trauma and have the luxury of imaging. I secretly rehearsed this for years. My hope is that you will never have to use it in practice.

ABOUT THE AUTHOR

Dr. Kevin Menes is an Emergency Room Physician in Las Vegas and was working the night of the Oct. 1 shooting. The team's non-standard approach to MCI was credited in saving hundreds of lives. His interests include Resuscitology, MCI, trauma, procedures and all the aspects of prehospital care and Emergency Medicine. He is a tactical physician with the Las Vegas Metropolitan Police Department SWAT team. He has taught various military special forces and other groups. He traveled to numerous locations teaching Mass Casualty Preparedness. He credits his residency in Emergency Medicine at St. John Hospital, Detroit for his knowledge and experience.
 

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