Thromboelastography (TEG) and its fraternal twin rotational thromboelastometry (ROTEM) are relatively new toys in the trauma community. They allow for (somewhat) rapid assessment of clotting function, and allow the trauma professional to surmise what products might push abnormal clotting characteristics back toward normal.
Many trauma centers already own this technology due to its use by non-trauma services. But there have been a growing number of research presentations on the topic over the last five years, and many centers are clamoring to buy these units for use in their MTP.
But remember, new technology is usually expensive, and isn’t always all it’s cracked up to be. TEG and ROTEM require a (often-times) new machine and a never-ending supply of disposable cartridges for use, like your ink jet printer. 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 correlated 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’ve see very few centers that have fully, effectively, and contemporaneously incorporated TEG or ROTEM into their massive transfusion protocol from start to finish.
The area where TEG and ROTEM are most helpful are in the “mop up” phase at the tail end of the MTP. These tools allow trauma professionals to determine exactly which products are needed to normalize parameters, and they frequently diverge from the 1:1:1 to 1:1:2 ratios at that point to achieve this.
If you don’t have one of these toys yet, make sure that you have a very good clinical reason to do so. If you do, think very carefully about how you can meaningfully incorporate it in the massive transfusion process and write it into your protocol.
Reference: All the bang without the bucks: defining essential point-of-care testing for traumatic coagulopathy. J Trauma 79(1):117-124, 2015.