How To Make TEG / ROTEM Useful

A lot of papers have been written on the use of thromboelastography in trauma. And pretty much any meeting or course you may attend has at least one talk on it. And I get it. It can be an important tool in treating trauma patients who have some sort of coagulation disturbance. It helps us figure out what specific part of the coagulation process is out of whack and suggests how we can fix it.

But there are a few problems, as I mentioned yesterday. And the “friction” that those issues cause overall decreases how useful it is. Here’s a partial list of the problems:

  • The equipment costs money, and the disposables that must be used for every patient do, too.
  • Where do you put the machine? Most hospitals can’t put one unit in every possible area it might be used.
  • How to you get the results to a care area if there is no unit there?
  • There is a significant learning curve for interpreting the results
  • How can it be integrated into the massive transfusion protocol?

The main issue is that the current state of TEG and ROTEM are very similar to the state of electrocardiography shortly after it’s discovery. Here’s what you got then:

In order to get the most from an EKG, you need to combine this tracing with that from other leads, do a bunch of measurements, look for abnormal shapes and elevations/depressions, etc.  This is exactly where we are with TEG and ROTEM today. Relatively crude, and it takes a lot of work to use it.

The tracing below shows where we are with EKGs today. A computer program looks at all the tracings, and rapidly applies a complex set of rules to come to a set of diagnoses. Notice in the image below that this reading is “unconfirmed.” But how many times in your career have you seen a cardiologist correct one of these? The machines are actually very good!

Bottom line: The tracing above is where we need to be with TEG and ROTEM. Instead of a clinician staring at a developing tracing and figuring out what products to give, these machines need to be just like an automated EKG machine. Sure, a human can still stare at the trace. But the machine will automatically monitor it, apply rules about what abnormalities are present and what is needed to correct them. Send off your blood specimen, and within minutes instructions like “infuse 2 units of plasma now” or “give 12u cryo now” appear. These may be displayed on a monitor in the treatment area, or be broadcast to the phone or pager of the responsible clinicians.

Current TEG/ROTEM equipment is what I would consider 1st generation. The next generation will reduce or remove much of the “friction” in the current process and allow us to really integrate TEG/ROTEM meaningfully into the massive transfusion protocol for trauma. And for anyone who develops this 2nd generation equipment, don’t forget my royalty checks for this idea! 

Related post:

What If You Don’t Have TEG For Trauma?

The new hot items in trauma care are thromboelastography (TEG) and ROTEM (thromboelastometry), a new spin on TEG from the TEM Corporation. These tools allow for in-depth assessment of factors that influence clotting. We know that rapidly recognizing and treating coagulopathy in major trauma patients can reduce mortality. So many trauma centers are clamoring to buy this technology, citing improved patient care as the reason.

But new technology is always expensive, and isn’t always all it’s cracked up to be. TEG and ROTEM require an expensive machine and a never-ending supply of disposable cartridges for use. Some hospitals are reluctant to provide the funds unless there is a compelling clinical need.

Surgeons at the University of Cincinnati compared the use of TEG with good, old-fashioned point-of-care (POC) INR testing in a series of major trauma patients seen at their Level I center.

Here are the factoids:

  • This was a retrospective review of 628 major trauma patients who received both TEG and POC INR testing using an iSTAT device over a 1.5 year period
  • Median ISS was 13, and there were many sick patients (20% in shock, 21% received blood, 11% died)
  • INR correlated with all TEG values, with better correlation in patients in shock
  • Both INR and TEG correlated well with treatment with blood, plasma, and cryoprecipitate
  • Processing time was 2 minutes for POC INR vs about 30 minutes for TEG
  • Charges for POC INR were $22,000 vs $397,000 for TEG(!!)

Bottom line: Point of care INR testing and TEG both correlate well with the need for blood products in major trauma patients. But POC INR is much cheaper and faster. Granted, the TEG gurus will say that you can tailor the products administered to meet the exact needs of the patient. But in all my travels, I have never visited a center that has fully and effectively incorporated TEG or ROTEM into their massive transfusion protocol. Before you make the financial leap to buy these new toys, make sure that you have a very good clinical reason to do so.

Related posts:

Reference: All the bang without the bucks: defining essential point-of-care testing for traumatic coagulopathy. J Trauma 79(1):117-124, 2015.

How To: Insert A Small Percutaneous Chest Tube

This short (10 minute) video demonstrated the technique for inserting small chest tubes, also known as “pigtail catheters.” It features Jessie Nelson MD from the Regions Hospital Department of Emergency Medicine. It was first shown at the third annual Trauma Education: The Next Education conference in September 2015, for which she was a course director.

Please feel free to leave any comments or ask any questions that you may have.

Related posts:
How To: Insert a regular chest tube for trauma
Pigtail catheters vs regular chest tubes
Tips for regular chest tubes 

What Does A Retained Surgical Sponge Look Like?

Surgeons and surgical residents rarely see these. And because it’s so uncommon, they frequently don’t recognize the telltale findings on radiographic studies. The TSA runs into the same problem in screening passengers for weapons and other hazards at airports. But it’s the bane of any surgeon’s existence. And it’s a major reason why OR personnel take such great pains to account for everything in the room. It is a catastrophe, and always a preventable one, when some piece of equipment goes missing and ends up left inside a patient.

A number of methods have been developed to try to eliminate this problem. They include careful counts, having someone record anytime anything is placed inside, x-rays, and most recently, RFID tags.

After counting, x-ray is the most common way to try to find missing objects. One would think that these foreign bodies would be easy to see. Metallic instruments are rather easy to spot. But many trauma professionals, even those who work in the OR, have never seen what a positive image of a sponge actually looks like. So here they are. You should never miss one on an xray now.

Surgeons typically use two types of sponges in the OR: Ray-Tec sponges and standard lap pads. Ray-Tecs look like a 4×8 piece of gauze with a mysterious blue string woven throughout it. The string is the only part that shows up on x-ray, and it is very thin and somewhat hard to see. Here are some Ray-Tec sponges outside the body:

And here’s one that was left inside. Note the little squiggle in the left lower quadrant and how easy it is to overlook.

On the other hand, a laparotomy pad is a 4×4 folded cloth pad that unfolds into a larger pad. It has a blue tag sewn in the corner, extending along one edge of the pad. Here’s what they look like outside the body:

And here’s one inside a patient. Note the irregular object in the right upper quadrant.

Bottom line: It’s important for anyone who works in the OR on any body part to be familiar with the appearance of these tags on x-rays. Since it’s generally impossible to get accurate counts before or after a trauma procedure, always image the involved body cavity looking for these telltale signs before closing the patient.

Note: These images taken from the internet. Patients not treated at Regions Hospital.

Gunshots And CT Scan Of The Abdomen

Abdominal gunshots and CT scanning are usually thought to be mutually exclusive. The usual algorithm generally means a prompt trip to the operating room. But as with many things in the management of trauma, there are always exceptions. The key is to understand when exactly one of those exceptions is warranted.

Exception 1: Did it really enter the abdomen? Gunshots have enough energy that they usually do get inside. However, freaky combinations of trajectory and body habitus do occur. There are three tests that must be passed in order to entertain the possibility that the bullet may not have made it inside your patient: physiology, anatomy, and physical exam. For physiology, the patient must be completely hemodynamically stable. Anatomically, the trajectory must make sense. If the known wounds and angles allow a tangential course make sense, then fine. But if there is a hole in the epigastrium and another next to the spine, you have to assume the bullet went straight through. Finally, the physical exam must be normal. No peritonitis. No generalized guarding. Focal tenderness only in the immediate area of any wounds. If all three of these criteria are passed, then a CT can be obtained to demonstrate the trajectory.

Exception 2: Did it enter an unimportant area of the abdomen? Well, there’s really only one of these, and that’s the area involving the right lobe of the liver and extending posteriorly and lateral to it. If the bullet hole(s) involve only this area, and the three tests above are passed, CT may confirm an injury that can be observed. However, there should only be a minimal amount of free fluid, and no soft tissue changes of any kind adjacent to bowel.

Exception 3: A prompt trauma lap was performed, but you think you need more information afterwards. This is rare. The usual belief is that the eyes of the surgeon provide the gold standard evaluation during a trauma lap. For most low velocity injuries with an easily understood trajectory, this is probably true. However, high velocity injuries, those involving multiple projectiles, or complicated trajectories (side to side) can be challenging for even the most experienced surgeon. Some areas (think retroperitoneum or deep in the pelvis) are tough to visualize completely, especially when there’s blood everywhere. These are also the cases most likely to require damage control surgery, so once the patient has been temporarily closed, warmed and resuscitated, a quick trip to CT may be helful in revealing unexpected shrapnel, unsuspected injuries, or other issues that may change your management. Even a completely unsurprising scan can provide a higher sense of security.

Bottom line: CT of the abdomen and gunshots to that area may actually coexist in some special cases. Make sure the physiology, anatomy and physical exam criteria are passed first. I also make a point of announcing to all trainees that taking these patients to CT is not the norm, and carefully explain the rationale. Finally, apply the concept of the null hypothesis to this situation. Your null hypothesis should state that your patient does not need a CT after gunshot to the abdomen, and you have to work to prove otherwise!