It happens from time to time. Your patient has a hemothorax or pneumothorax and you insert a chest tube. Well done! But then the xray comes back:
The last hole in the drain is outside the chest! What to do???
Here are the questions that need to be answered:
Leave comments below regarding what you do. Hints and final answers in my next post!
Trauma patients tend to try to bleed to death. And trauma professionals try to stop that bleeding. They also frequently have to replace the blood products that were lost, which includes red blood cells, plasma, platelets, and more.
From a red blood cell standpoint, we have a long history of using group O- packed red cells as the so-called universal donor product. The problem is that only about 5% of the world population has this blood type, so it can be scarce.
To address this, many centers have moved toward using O+ blood for select patients. This blood type is much more prevalent (about 50% worldwide). The only difference is the positive Rh factor which has little impact on males, or females who are not in their child-bearing years. If an allergic reaction occurs, it is typically mild.
But what about plasma? This is interesting stuff. When selecting red cells, we want them to have no ABO group antigens on them so they don’t provoke a reaction. But plasma is just the opposite. We don’t want any ABO group antibodies in it. And the only plasma without antibodies comes from people who have all of them (A and B) on their red cells. This means people with type AB+ blood. Unfortunately, this is the other rare blood type, so there’s not a lot to go around. Worldwide, about 5% of people are AB+ and less than 1% are AB-.
So why couldn’t we do something like we did with packed red cells and substitute a more common blood type that evokes little immune response? The American Association of Blood Banks (AABB) has authorized both AB and A plasma for use in emergency situations. Unfortunately, the safety profile for using group A has not been very well studied, particularly in trauma patients needing massive transfusion.
The authors of the PROPPR study re-analyzed the data from it to try to answer this question. As you may recall, PROPPR was published in 2015 and compared safety and effectiveness of transfusion ratios at 1:1:1 to 1:1:2 (plasma : platelets : red cells).
The study group selected patients from the dataset who received at least one unit of emergency release plasma (ERP), defined as product given before the patient’s ABO type had been determined. Nicely enough, 12 sites transfused group AB ERP and 9 sites gave group A. One site gave both A and AB.
The authors looked at in-hospital mortality at 30 days, and a host of complications. Here are the factoids:
The authors concluded that, statistically, the use of group A plasma was not inferior to the use of group AB. The authors stated that cautious use of group A is an acceptable option, especially if group AB is not readily available.
Bottom line: Here we go again. Always be careful when reading a study that suggests non-inferiority of one thing compared to another. There are a lot of potential issues here:
So with significant baseline differences in study groups and a potentially underpowered study, don’t read non-inferiority as meaning that use of group A plasma is okay. We still just don’t know. What this study really shows is that you can “get away with” using low titer group A plasma if you run out of AB. But it shouldn’t be your go to product yet. To figure out the real safety profile, we need to do a real “PROPPR” study. Get it?
Reference: Group A emergency-release plasma in trauma patients requiring massive transfusion, J Trauma 89(6):1961-1067, 2020.
Syncope accounts for 1-2% of all ED visits, and is a factor in some patients with blunt trauma, especially the elderly. If syncope is suspected, a “syncope workup” is frequently ordered. Just what this consists of is poorly defined. Even less understood is how useful the syncope workup really is.
Researchers at Yale retrospectively looked at their experience doing syncope workups in trauma patients. They were interested in seeing what was typically ordered, if it was clinically useful, and if it impacted length of stay.
A total of 14% of trauma patients had syncope as a possible contributor to their injury. The investigators found that the following tests were typically ordered in these patients:
Most of this testing was normal. About 3% of cardiac enzymes were abnormal, as were 5% of carotid imaging and 4% of echocardiograms.
Important! Of the patients who underwent an intervention after workup, 69% could have been identified based on history, physical exam, or EKG and did not depend on any of the other diagnostic tests.
Is it possible to determine a subset of this population that may show a higher yield for this screening? Surgeons at Temple University in Philadelphia found that there was little utility in using carotid duplex studies. They did note that patients with a history of heart disease were more likely to have an abnormal EKG, and that an abnormal EKG predicted an abnormal echo. Overall, only patients with a history of significant cardiac comorbidity, older age, and higher ISS had findings requiring intervention.
Bottom line: Don’t just reflexively order a syncope workup when there is a question of this problem. Think about it first, because the majority of these studies are nonproductive. They are not needed routinely in trauma patients with “syncope” as a contributing factor. Obtain a good cardiac history, and if indicated, order an EKG and go from there. See the practice guideline proposed by the Temple group below. And be sure to include the patients primary doctor in the loop!
References:
In my last post, I explained why TEG is not so easy to use. Today, I’ll share the new Eastern Association for the Surgery of Trauma (EAST) practice management guidelines for using TEG and its twin, ROTEM for bleeding patients.
TEG first appeared in the trauma literature in 2008. A paper by John Holcomb showed that it was superior to the standard lab tests (PT, aPTT, and activated clotting time) in monitoring hemorrhagic shock in pigs. Since then, research has exploded with TEG papers. There have been about 50 published annually for the last four years.
In this month’s Journal of Trauma, EAST published their most recent practice management guideline, dedicating it to TEG. They identified over 6,000 potential papers and ultimately settled on 38 articles. They used them to attempt to answer three questions regarding use of these devices during resuscitation.
Question 1
In adult trauma patients with ongoing hemorrhage, should TEG/ROTEM be used vs non-TEG/ROTEM monitoring to guide transfusion strategy in order to reduce mortality, blood product transfusions and the need for additional hemostatic interventions such as angioembolization, endoscopy, or operation?
Answer: Only seven studies were found regarding this question. All but one showed no difference in 24 hour and hospital mortality. They also showed an inconsistent effect on blood product usage with some showing no difference and some shower less transfused product.
Nonetheless, EAST “conditionally recommended” the use of TEG/ROTEM. This is based solely on the presumption that it can reduce the risk of blood transfusions by using a test that is harmless.
Question 2
In adult surgery patients with ongoing hemorrhage, should TEG/ROTEM be used vs non-TEG/ROTEM monitoring to guide transfusion strategy in order to reduce mortality, blood product transfusions and the need for additional hemostatic interventions such as angioembolization, endoscopy, or operation? Note the shift here to non-trauma patients.
Twenty one studies were found addressing this question. Most papers showed no difference in reoperation rate. There were also no consistent differences in transfusion of various blood products. And the vast majority showed no difference in mortality.
But once again, EAST conditionally recommended the use of this test in these patients, mainly because it is believed to be harmless.
Question 3
In adult critically ill patients with ongoing hemorrhage, should TEG/ROTEM be used vs non-TEG/ROTEM monitoring to guide transfusion strategy in order to reduce mortality, blood product transfusions and the need for additional hemostatic interventions such as angioembolization, endoscopy, or operation?
There were only 10 studies relating to this question, and they included patients with a variety of surgical and medical problems. TEG/ROTEM was no better than non-TEG parameters in predicting the need to transfuse, but did somewhat better than clinical judgement. Once again, there was no consistent effect on the number of transfusions given, although some studies showed that use of non-TEG/ROTEM studies resulted in fewer units of red cells, platelets, and cryoprecipitate given.
Interestingly, although there was little difference in the number of units transfused, fewer patients required transfusion using TEG/ROTEM. There was no difference in mortality or interventions to stop bleeding.
Yet again, EAST conditionally recommended use of TEG/ROTEM in these patients despite the very low level of evidence. Again, this is mainly because of the lack of perceived harm in using it, and the possibility that it might reduce exposure to blood products.
Bottom line: Hmm. I remain skeptical. What EAST is saying is that, hey it’s harmless and there’s a chance that it might reduce a patient’s exposure to blood products, so why not? I have a vial of bat wings and eye of newt that might do the same thing. As long as it’s harmless, right?
Well, it may be clinically harmless, but it costs money and time. First, you have to buy the machine. Luckily, they are much cheaper than a CT scanner. But then the manufacturer kills you with the disposables. Like a cheap inkjet printer, you have to keep buying $40 ink cartridges every few weeks to keep it working. Except TEG cartridges cost more than $40.
And don’t overlook the time spent training people in how to interpret the curves. And developing a system to obtain the specimen and pay people to run the equipment. It all adds up, and yet the papers can’t show us any dramatic clinical results.
I’ll probably irritate the TEG/ROTEM true believers, but it still seems like a device searching for a great clinical problem to solve. IMHO we need much more high-quality research to help us figure out how this tool can help us with our trauma / surgical / critical care patients.
Reference: Thromboelastography and rotational thromboelastometry in bleeding patients with coagulopathy: Practice management guideline from the Eastern Association for the Surgery of Trauma. J Trauma 89(6):999-1017, 2020.
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. And the “friction” that those issues cause overall decreases how useful it is. Here’s a partial list of the problems:
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!
In my next post, I’ll review the new EAST guidelines for the use of TEG and ROTEM.