Category Archives: Trauma

Goal-directed Hemostatic Resuscitation of Trauma-induced Coagulopathy: Time for TEG?

Along with the usual suspects in the world of emergency medicine / FOAMed podcasts, I’ve tried to start listening to the educational podcasts being generated by those outside of our specialty — the Eastern Association for the Surgery of Trauma, EAST, recently had a great episode of their podcast (“Traumcast”) that featured Dr. Gene Moore, chief of trauma at Denver Health reviewing a single-center RCT comparing the use of viscoelastic coagulation assays to traditional coagulation testing such as INR and PTT in guiding resuscitation of trauma patients.

I went to medical school in Houston and did my clinical rotations at Memorial Hermann, where John Holcomb did his work looking at the use of rotational thromboelastography, including the development of a very robust system for getting TEG results to the trauma team within 15 minutes of the arrival of a patient to the trauma bay. The system they developed also provided automated guidance for the administration of specific blood products based off of the TEG assay, and is described in the second article linked below from Blood: How I treat patients with massive hemorrhage, on which Dr. Holcomb is the coordinating author.

I felt like this made a ton of sense — in the often coagulopathic trauma patient, we have shown over and over again that saline is not the resuscitative fluid of choice, and have more recently demonstrated in large, prospective, pragmatically-designed trials the superiority of using more physiologic (or “balanced”, as many surgeons refer to them) protocols for transfusing bleeding patients. Why not use more dynamic information to help inform the choice of which product goes first to fix the specifically broken link in the cascade of coagulation, as these viscoelastic testing assays seem to offer?

In this study, patients requiring massive transfusion activation were randomized in a block fashion to either have transfusion of blood products guided by TEG or by traditional coagulation assays. MTP activation was based on the Resuscitation Outcome Consortium criteria: SBP <70 mm Hg or SBP 70–90 mm Hg with heart rate > 108 beats/min, in addition to any of the following injury patterns: penetrating torso wound, unstable pelvic fracture, or FAST suspicious of bleeding in more than one region.

One hundred eleven patients were included in an intent-to-treat analysis, evenly split between the groups. Survival in the TEG group was significantly higher than the conventional MTP group (log-rank P = 0.032, Wilcoxon P = 0.027); 20 deaths in the control group (36.4%) compared with 11 in the TEG group (19.6%) (P = 0.049). Most deaths occurred within the first 6 hours from arrival (21.8% CCA group vs 7.1% TEG group) (P = 0.032).

Keeping in mind that TEG is a diagnostic tool rather than a treatment, and the relatively small numbers in this single central study, I don’t know that anyone could definitively say that the use of TEG is responsible for the increased survival seen here, but the results are impressive. Given the additional information conveyed by the TEG or other functional coagulation assays, I think that more broad deployment (including outside the OR, as they have at Memorial Hermann, where the TEG is the first test run off of the trauma activation patient, and where the results– along with a computerized interpretation of the graph with a recommendation for transfusion– print off on a laser printer in the trauma bay automatically) makes a lot of sense.

We should all be learning how to interpret these assays, especially in EM where we are often initiating the massive transfusion and resuscitation of these sick trauma patients (or other exsanguinating patients — I think it stands to reason that functional clotting assays would be much more useful in patients with other kinds of coagulopathy, e.g. liver failure or and sepsis) — I think this is now reaching a broader audience, as just recently Josh Farkas covered the use of TEG in sepsis-induced coagulopathy on PulmCrit and an article in EM Resident magazine covered the basics of TEG. Hopefully as more and more people learn about these technologies, we’ll see wider deployment and utilization, resulting in better care and smarter transfusion strategies.

References

Gonzalez E1, Moore EE, Moore HB, Chapman MP, Chin TL, Ghasabyan A, Wohlauer MV, Barnett CC, Bensard DD, Biffl WL, Burlew CC, Johnson JL, Pieracci FM, Jurkovich GJ, Banerjee A, Silliman CC, Sauaia A. Goal-directed Hemostatic Resuscitation of Trauma-induced Coagulopathy: A Pragmatic Randomized Clinical Trial Comparing a Viscoelastic Assay to Conventional Coagulation Assays. Ann Surg. 2016 Jun;263(6):1051-9. PMID: 26720428. [PubMed] [Read by QxMD]
Johansson PI1, Stensballe J2, Oliveri R3, Wade CE4, Ostrowski SR3, Holcomb JB4. How I treat patients with massive hemorrhage. Blood. 2014 Nov 13;124(20):3052-8. PMID: 25293771. [PubMed] [Read by QxMD]

Evaluation of Cervical Spine Clearance by Computed Tomographic Scan Alone in Intoxicated Patients With Blunt Trauma

One common and vexing problem I’ve run into thus far in residency is the intoxicated patient, found down, brought in by EMS in a rigid cervical collar placed because of the presumption of possible trauma leading to an unstable cervical injury. The efficacy and necessity of cervical collars has been debated elsewhere, and I’m not looking to discuss that here — what I’m more interested is, if these patients have a negative CT scan (for better and for worse, fairly common practice in those unable to give a reliable exam, especially if they have any sign of trauma on them), can we safely remove their collar?

This study, by the “Pacific Coast Surgery Association” and published in JAMA Surgery, prospectively evaluated 1668 intoxicated adults with blunt trauma who underwent cervical spine CT scans over one year at a single Level I trauma center. Intoxication was defined based on the results of urine and blood testing, and the outcome of interest was clinically-significant cervical spine injuries that required cervical immobilization (not necessarily surgical fixation).

The authors wanted to evaluate the negative predictive value of a normal CT scan in the intoxicated patient to determine whether this would allow safe removal of their cervical collar– it is well-known that some injuries (e.g. unstable ligamentous injuries or spinal cord injuries without fractures of the vertebrae) may not be identifiable on a CT scan, and in the patient who is altered, it may be difficult to elicit exam findings that would tip a practitioner off to the presence of these injuries.

So what did they find? In intoxicated patients, the negative predictive values of a CT scan read as negative for acute injury were 99.2% for all injuries and 99.8% for unstable injuries.  There were five false-negative CTs, with 4 central cord syndromes without associated fracture. There was also one false-negative for a potentially unstable injury identified in a drug-intoxicated patient who presented with clear quadriplegia on examination. All of these were detected on MR imaging. About half of the intoxicated patients with the negative CT went on to be admitted with their cervical collar left on. None of these intoxicated patients went on to have an injury identified later, or to have any neurologic deficit, leading to a conclusion of a NPV of 100% in that cohort.

My takeaway from this paper: while there are some weaknesses, e.g. the lack of protocol-based care and the significant heterogeneity in terms of “intoxication”, it seems reasonable to take away from this that a negative CT scan done on a modern scanner and read by an experienced trauma radiologist or neuroradiologist does allow you to safely clear the collar of an intoxicated patient who does not have any gross neurologic deficits. This data lends further support to the 2015 recommendations from the Eastern Association for the Surgery of Trauma who in a systematic review and meta-analysis “found the negative predictive value for identifying unstable CSIs to be 100% and thus have made a conditional recommendation for cervical collar removal based on a normal high-quality CT scan”. Adopting this practice could help minimize unnecessary testing (including expensive MRIs that are more likely to show false positives than to identify clinically-significant injuries) , allow for earlier disposition of patients from the emergency department, increase patient comfort, and decrease the emotional and cognitive burden placed on providers who otherwise often have to continuously struggle to keep patients adherent to immobilization practices.

References

Bush L1, Brookshire R1, Roche B1, Johnson A1, Cole F1, Karmy-Jones R1, Long W1, Martin MJ2. Evaluation of Cervical Spine Clearance by Computed Tomographic Scan Alone in Intoxicated Patients With Blunt Trauma. JAMA Surg. 2016 Jun 15. PMID: 27305663. [PubMed] [Read by QxMD]