Category Archives: Resuscitation

Resuscitation

When To Stop The Massive Transfusion Protocol

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Initiating the massive transfusion protocol (MTP) is generally easy. Some centers use the Assessment of Blood Consumption score (ABC). This consists of four easy parameters:

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

The presence of two or more indicators reliably predicts a 50% chance of needing lots of blood.

The shock index (SI) is also used. It’s more quantitative, just divide the heart rate by the systolic blood pressure. The normal value is < 0.7. As it approaches 0.9, the risk for massive transfusion doubles. This technique requires a little calculation, but is easily doable.

Or you can just let your trauma surgeons decide when to order it. Unfortunately, this sometimes gets forgotten in the mayhem.

However it got started, your MTP is now humming right along. How do you know when to stop? This is much trickier, and unfortunately can’t be as easily quantified. Here are the general principles:

  • All surgical bleeding must be controlled. Hopefully your patient didn’t get too cold or acidotic during the case, resulting in lots of difficult to control nonsurgical bleeding (oozing).
  • Hemodynamics are stabilizing. This doesn’t necessarily mean they are quite normal yet, just trying to approach it.
  • Vasopressors are off, or at least being weaned.
  • Volume status is normalizing. You may need an echo to help with this assessment.

If you have TEG, it probably wasn’t very useful. Until now. This is the ideal time to run a sample so you can top off any specific products your patient might need.

If you don’t have TEG, get a full coag panel including CBC, INR, PTT, lytes with ionized calcium.

Once the patient is in your ICU, continue monitoring and tweaking their overall hemodynamic and coagulation status until they are approaching normal. Then watch out for additional insults or any new and/or unsuspected bleeding. If this does occur, the threshold for return to the OR should be low. Unfortunately it is common for arteries in spasm to resume bleeding after warming and vasodilation.

When you are finally satisfied that there is no more need for the MTP, let your blood bank know so they can start restocking products and getting ready for the next go around!

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Resuscitation

Blunt Traumatic Arrest In Kids: Are They Little Adults?

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Over and over, we hear that children are not just little adults. They are a different size, a different shape. Their “normal” vital signs are weird. Drug doses are different; some drugs don’t work, some work all too well.

But in many ways, they recover more quickly and more completely after injury. What about after what is probably the biggest insult of all, cardiac arrest after blunt trauma? The NAEMSP and the ACS Committee on Trauma previously released a statement regarding blunt traumatic arrest (BTA):

 “Resuscitation efforts may be withheld in any blunt trauma patient who, based on out-of-hospital personnel’s thorough primary patient assessment, is found apneic, pulseless, and without organized ECG activity upon arrival of EMS at the scene.“

The groups specifically point out that the guidelines do not apply to the pediatric population due to the scarcity of data for this age group.

The Children’s Hospital of Los Angeles and USC conducted a study of the National Trauma Data Bank, trying to see if children had a better outcome after this catastrophic event. Patients were considered as children if they were up to and including age 18.

Here are the factoids:

  • Of 116,000 pediatric patients with blunt trauma, 7,766 had no signs of life (SOL) in the field (0.25%)
  • The typical male:female distribution for trauma was found (70:30)
  • 75% of those without SOL in the field never regained them. Only 1.5% of these survived to discharge from the hospital.
  • 25% regained SOL with resuscitation, and 14% of them were discharged alive.
  • 499 patients underwent ED thoracotomy, and only 1% survived to discharge. There was no correlation of thoracotomy with survival.
  • It appeared that there was a tendency toward survival for the very young (age 0-4) without SOL, but statistical analysis did not bear this out

Bottom line: Children are just like little adults when it comes to blunt cardiac arrest after trauma. Although it is a retrospective, registry-based study, this is about as big as we are likely to see. And don’t get suckered into saying “but 1.5% with no vital signs ever were discharged!” This study was not able to look at the quality of life of survivors, but there is usually significant and severe disability present in the few adult survivors after this event.

Feel free to try to re-establish signs of life in kids with BTA. This usually means lots of fluid and/or blood. If they don’t respond, then it’s game over. And, like adults, don’t even think about an emergency thoracotomy; it’s dangerous to you and doesn’t work!

Reference: Survival of pediatric blunt trauma patients presenting with no signs of life in the field. J Trauma 77(3):422-426, 2014.

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Resuscitation

REBOA For Pelvic Fractures

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Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) is one of the newer shiny toys that trauma professionals have adopted over the past 8 years or so. It is used to buy time for a patient who is near arrest in order to temporarily stop bleeding and get them to the operating room.

And as with all new toys, everyone wants one! I have always advised caution. Adopt a data-based approach to toy usage. Unfortunately information has been accumulating ever so slowly on this one. To help remedy this, the AAST created a registry in 2013 to consolidate the low REBOA experience numbers accruing across the US.

A group of seven surgeons representing higher-volume REBOA centers collaborated to review the AAST AORTA registry, which prospectively collects data on patients who undergo aortic occlusion. They retrospectively reviewed over six years of data on adult patients receiving REBOA for pelvic injury. They examined demographic, procedural, and outcome data in patients who underwent this procedure, both with and without other interventions like preperitoneal packing, angioembolization, or external fixation. For inclusion in the study, patients needed to have sustained blunt trauma and survived beyond the emergency department.

Here are the factoids:

  • Of the 207 patients with pelvic (Zone 3) REBOA in the registry, only 160 met inclusion criteria
  • Patients who only had REBOA suffered a mortality rate of 40% (5% in OR and 35% in the ICU)
  • Patients who had REBOA plus one of the other interventions had a 31% mortality rate (6% in OR and 25% in ICU)
  • Patients who had REBOA plus two other interventions also had a 31% mortality rate (12% in OR and 30% in the ICU)
  • Adding external fixation with or without another adjunct appeared to decrease mortality by half (from 50% to about 25%)
  • Complications were very common in all subsets, ranging from 35% to 86%
  • Patients receiving more interventions typically were more severely injured
  • No combination of REBOA and adjuncts was superior, but addition of an external fixator did appear to improve survival
  • Patients receiving angiographic embolization had a higher incidence of AKI, sometimes resulting in the need for dialysis
  • There were no significant outcome differences with REBOA use alone or with additional adjuncts

Bottom line: This was a primarily a descriptive study of how REBOA is integrated into pelvic fracture care at select US trauma centers. It was not really designed to compare the efficacy of REBOA vs preperitoneal packing vs angioembolization vs external fixation of the pelvis.

But it does show that survival remains dismal in these patients and the complication rates of REBOA + adjunct use are considerable. The authors correctly conclude that REBOA is being used in the treatment of pelvic fractures, frequently with the addition of other adjuncts. They state that the benefit of more interventions must be balanced against the potential for complications. And finally, they note that there is a need to fill in the evidence base if we are ever to adopt REBOA as a standard of care for select pelvic fractures.

What does this mean to all of you who are thinking of playing with this toy? Proceed with caution! The learning curve is steep. The complication rate is high. The opportunity for mayhem is great. This means that you must proceed deliberately. Get some advanced training with this technique. Use your performance improvement program to impartially critique its use with every deployment. And submit your experience to the national registry so we can all learn from your experience and figure out how to optimize use of this tool.

Reference: Patterns and outcomes of zone 3 REBOA use in the management of severe pelvic fractures: Results from the AAST Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery database. J Trauma 90(4):659-665, 2021.

 

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Prehospital, Resuscitation

Best Of EAST #16: More On TXA

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Here’s another abstract dealing with TXA. But this one deals with the classic CRASH-2 use for patients with major bleeding. The original patient showed that TXA improves survival if given within 3 hours of injury. More and more prehospital units (particularly aeromedical services) have been administering TXA enroute to the trauma center to ensure that this drug is given as early as possible.

Many of these same services carry packed cells (or in rare cases, whole blood) so that proper resuscitation can be started while enroute as well. A multicenter group led by the University of Pittsburgh evaluated the utility of giving both TXA and blood during prehospital transport.

Their study summarizes some of the results of the Study of Tranexamic Acid During Air and Ground Medical Prehospital Transport Trial (STAAMP Trial). This study ran from 2015 to 2019 and randomized patients to receive either TXA or placebo during air or ground transport to a trauma center. It included blunt or penetrating patients at risk for hemorrhage within 2 hours of injury who were either hypotensive or tachycardic. Outcome measures included 30-day mortality, 24-hour mortality, and a host of complications.

This abstract outlines a secondary analysis that retrospectively reviewed the impact of using prehospital packed red cells (pRBC) in addition to the TXA/placebo during transport. 

Here are the factoids:

  • There were 763 patients in total, broken down as follows
    • TXA only – 350
    • pRBC only – 35
    • TXA + pRBC – 22
    • Neither – 356
  • Patients who received blood with or without TXA were more severely injured with ISS 22 vs 10-12 in the non-pRBC groups
  • Mortality was higher in the pRBC (23%) and TXA+pRBC groups (29%)
  • TXA alone did not decrease mortality
  • TXA + pRBC resulted in a 46% reduction in 30-day mortality but not at 24 hours
  • packed cells alone decreased 24-hour mortality by 47%

The authors concluded basically what was stated in the results: short term mortality was decreased by pRBC alone, and 30-day mortality with TXA + pRBC. They recommended further work to elucidate the mechanisms involved.

Bottom line: This abstract may also suffer from the “low numbers” syndrome I’ve written about so many times before. The conclusions are based on two small groups that make up only 7% of the entire study group. And these are the two groups with more than double the ISS of the rest of the patients. The authors used some sophisticated statistics to test their hypotheses, and they will need to explain how and why they are appropriate for this analysis. Nevertheless, the mortalities in the blood groups number only in the single digits, so I worry about these statistics.

Here are my questions for the authors and presenter:

  • How do you reconcile the significantly higher ISS in the two (very small) groups who got blood? How might this skew your conclusions regarding mortality? Couldn’t the TXA just be superfluous?
  • How confident are you with the statistical analysis? Could the results be a sampling error given that red cells were given to only 7% of the overall study group?
  • I am having a difficult time understanding the conclusion that mortality was reduced in the blood groups. Specifically, it is stated that 24-hour mortality is reduced by 47% in the blood-only group.  But the mortality is 14% (5 patients)! Reduced 47% from what? I don’t see any other numbers to compare with in the table. Confusing!

Obviously, there must be more information that was not listed in the abstract. Can’t wait to see it!

Reference: PREHOSPITAL SYNERGY: TRANEXAMIC ACID AND BLOOD TRANSFUSION IN PATIENTS AT RISK FOR HEMORRHAGE. EAST 35th ASA, oral abstract #39.

 

 

Reference: PREHOSPITAL SYNERGY: TRANEXAMIC ACID AND BLOOD TRANSFUSION IN PATIENTS AT RISK FOR HEMORRHAGE. EAST 35th ASA, oral abstract #39.

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Head, Resuscitation

Best Of EAST #15: Prehospital TXA

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The world is divided into trauma centers that are TXA believers and those that are TXA nonbelievers. It all depends on how one interprets the CRASH-2 data and subsequent studies. Then came CRASH-3 with TXA use for patients with TBI. This large study found improved survival in patients with mild to moderate head injury when given “early.”

The group at Oregon Health Science University tried to better define this concept of “early.” They examined early vs later administration of TXA in patients with moderate to severe TBI. Note that this degree of head injury is a bit different than CRASH-3 (mild to moderate in CRASH-3 and moderate to severe in this one). This was a multicenter trial that included patients with GCS < 12 and who were hypotensive with SBP < 90. Patients received either a 1g bolus followed by a 1g infusion over 8 hours, or a 2 g bolus only. The authors subdivided these patients into early administration (<45 minutes after injury) or late (45 minutes to 2 hours after injury).

Here are the factoids:

  • There were 354 patients in the early administration group and 259 in the late group
  • All outcomes, including 1 month and 6 month mortality and the extended Glasgow outcome scale were not significantly different between early and late groups (exact numbers were not given)
  • There was no difference in secondary complications between the groups (again, exact numbers or complication types were not given)

The authors concluded that there was no difference in outcomes in early vs later administration of TXA in these head injured patients. They suggest that patients can be given TXA anytime within two hours without loss of benefit.

Bottom line: Essentially, this ends up as a noninferiority study. The biggest question with this type of study is, do you have enough subjects to detect a significant difference? Taken to an extreme, let’s say you have 5 patients who receive a drug who are compared to 5 who did not for some mystery condition. Three who did not get the drug die (60% mortality), but only two who get it do (40% mortality). In relative terms, there was 33% decrease in mortality with the drug. But in absolute terms, it was one patient. Would anyone see this as a significant result with such small numbers?

But now multiply by a thousand, and 300 die without the drug and only 200 die who were given it. The relative difference is the same, but the absolute difference is beginning to look large and significant.

So the smaller study won’t meet the test of significance but the larger one will. The key question in the TXA study here is, do they have enough patients enrolled to show there is no real difference between the groups? I love doing back of the napkin power analyses, and I admit I certainly don’t have all the numbers and probabilities needed for a precise calculation. But the groups sizes in this study (354 vs 259) seem a bit small to achieve significance unless there are large disparities in outcomes. 

I certainly recognize that it’s just not possible to put all the relevant information for a research project into a four paragraph abstract. One would need to be able to submit 12 slide PowerPoint decks. So I’m sure more info will be available as I take in the presentation next Friday.

Here are my questions for the authors and presenter:

  • The study is nicely designed as a randomized, double-blind trial, but how did you blind one vs two doses? Did everyone get an infusion of something, TXA vs saline?
  • Why did you select 45 minutes as the cutoff for early vs late administration? Was this arbitrary or is it based some data?
  • Show us the power analysis that demonstrates the total number of patients in the study is sufficient to show us true non-significance in your results.
  • And I’m sure you will show the actual survival and complications numbers (and type) in the presentation, since they were not available in the abstract.

Reference: THE EFFECTS OF TIMING OF PREHOSPITAL TRANEXAMIC ACID ON OUTCOMES AFTER TRAUMATIC BRAIN INJURY. EAST 35th ASA, oral abstract #40.

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