All posts by The Trauma Pro

Using Your ABCs To Predict Massive Transfusion

It’s nice to have blood available early when major trauma patients need it. Unfortunately, it’s not very practical to have several units of O neg pulled for every trauma activation, let alone activate a full-blown massive transfusion protocol (MTP). Is there any way to predict which trauma patient might be in need of enough blood to trigger your MTP?

The Mayo Clinic presented a paper at the EAST Annual Meeting today that looked at several prediction systems and how they fared in predicting the need for massive transfusion. Two of the three systems (TASH – Trauma Associated Severe Hemorrhage, McLaughlin score) are too complicated for practical use. The Assessment of Blood Consumption tool is simple, and it turns out to be quite predictive. 

Here’s how it works. Assess 1 point for each of the following:

  • Heart rate > 120
  • Systolic blood pressure < 90
  • FAST positive
  • Penetrating mechanism

A score >=2 is predictive of massive transfusion. In this small series, the sensitivity of ABC was 89% and the specificity was 85%. The overtriage rate was only 13%.

The investigators were satisfied enough with this tool that it is now being used to activate the massive transfusion protocol at the Mayo Clinic.

Bottom line: ABC is a simple, easy to use and accurate system for activating your massive transfusion protocol, with a low under- and over-triage rate.

Reference: Comparison of massive blood transfusion predictive models: ABC, easy as 1,2,3. Presented at the EAST 24th Annual Scientific Assembly, January 26, 2011, Session I Paper 4. Click here to view the abstract.

EAST 24th Annual Scientific Assembly

I’m currently attending the EAST annual meeting. I’ll be tweeting about all the interesting papers and events that are presented. In order to make them easy to find, I’ll be using the hashtag #east2011

In addition I’ll also be doing a more in-depth analysis of some of the more interesting abstracts. You can find the abstracts for all the oral presentations here. Feel free to send me requests to talk about the ones you find fascinating!

Does Interrupting DVT Prophylaxis Increase Risk for DVT/PE?

Deep venous thrombosis is a common concern in trauma care. Most trauma centers have well defined protocols for prophylaxis and surveillance. Ongoing use of pharmacologic thromboprophylaxis (PTP) in patients with traumatic brain injury (TBI), or in patients who need surgical procedures is controversial.  We have all experienced some form of “prophylaxis interruptus”, where our orthopedic or neurosurgical colleagues want us to forego or interrupt ongoing administration of heparin products. Does this create new problems?

A trial was conducted at two Denver trauma centers, trying to clarify the optimal administration of PTP in patients with stable TBI. One cohort received PTP, the other did not (either not indicated, short stay, or already on blood thinners). The group receiving PTP was also stratified into those who received it continuously and those who had interruptions in treatment.

They found that the incidence of DVT and PE was similar for patients receiving PTP vs those not receiving it. The two groups were very different, though, because the ones who did not receive it had less severe injuries and were more likely to be ambulating by discharge.  The most interesting finding was that being started on PTP and then interrupting it increased the incidence of DVT fourfold.

What is it about prophylaxis interruptus that is so risky? First, there were only 480 patients in this study, so statistical anomalies could be present. Could it be that the conditions (TBI) and operations that cause it to be interrupted greatly increase the risk? Unfortunately this study can’t answer those questions.

The bottom line: DVT and its prophylaxis is still a muddy concept. What we really need to do is to find out if PTP is really necessary in all the patients in whom we are using it. It would also be helpful if we knew how harmful it really is in patients with significant bleeding in their head, or in patients who need to undergo surgery. One alternative, if this paper pans out, is to begin with mechanical prophylaxis until cleared by neurosurgery and all operations are completed. For now, it’s not yet appropriate to change your existing practice and procedures.

Reference: Interrupted pharmocologic prophylaxis increases venous thromboembolism in traumatic brain injury. J Trauma 70(1):19-26, 2011.The term “prophylaxis interruptus” was coined by Tom Esposito in his discussion of this paper.

AAST Revises Renal Injury Grading

Organ injury scaling was developed to give clinicians and researchers a common language for describing and studying the effects of trauma. The Organ Injury Scaling classification for kidney injuries was developed by the AAST in 1989. Over time, it was recognized that grades IV and V were somewhat confusing, and some injuries were not originally included. An updated grading system was published this month to correct these shortcomings.

Grades I, II, and III remain unchanged. Grades IV and V are updated as follows:

  • Grade IV – originally encompassed contained injuries to the main renal artery and vein, and collecting system injuries. Revision: adds segmental arterial and venous injury, and laceration to the renal pelvis or ureteropelvic junction. Multiple lacerations into the collecting system used to be considered a shattered kidney (Grade V), but now remains Grade IV.
  • Grade V – orignally included main renal artery or vein laceration or avulsion, and multiple collecting system lacerations (shattered kidney). The revised classification includes only vascular injury (arterial or venous) and includes laceration, avulsion or thrombosis.

Reference: Revision of current American Association for the Surgery of Trauma renal injury grading system. J Trauma 70(1):35-37, 2011.

How To Identify Sick Pediatric Trauma Patients Before They Get Too Sick

We all have a pretty good idea of when an inpatient adult trauma patient is getting into trouble. Most rapid response teams have a set of criteria that are used by nursing personnel to initiate an RRT response. However, children who are beginning to decompensate can show it in more subtle ways. Fortunately, there is a tool that can be used to identify children who are showing early signs of developing problems.

The Pediatric Early Warning Signs tool (PEWS) is an objective system for assessing the potential for deterioration in a child. It can be customized based on institutional needs, and typically has behavioral, cardiovascular, and respiratory components. At our pediatric trauma center, we added a urinary output component as well. Scoring for each component ranges from 0 (best) to 3 (worst).

The total score is calculated, and is used to classify the child as green (benign) to red (immediate action needed). Again, these thresholds can be adjusted by each hospital. At our center, nursing calculates the PEWS score every 4 hours on non-ventilated patients.

Score category and actions are as follows:

  • Green (0-3 points) – no action, reassess as ordered
  • Yellow (4-6 points) – notify charge nurse, resident and attending physician
  • Red (7 or more points) – call rapid response team, resident and attending physician
  • A score of 3 in any category – call resident and attending physician

We implemented this system earlier this month and will be validating it during the coming year. Our hope is that it will reduce the number of RRT and code calls by identify deterioration at a much earlier stage.

You can download a copy of our PEWS instrument here. Thanks to Tracy Larsen RN, our pediatric Trauma Program Manager, for providing information on this system.