Here is the fifth and final installment of my series summarizing the Austrian consensus paper on management of TBI patients with intracranial hemorrhage. The previous posts have run the gamut from diagnostic tests to detection of specific drugs to management. I’ve covered platelet inhibitors and Vitamin K antagonist reversal in previous posts, and today I’ll go over the panel’s reversal strategies for the direct oral anticoagulant drugs (DOACs).
Q1. Should idarucizumab (Praxbind) always be administered to patients with hemorrhagic TBI who are taking dabigatran (Pradaxa).
Answer: Only in cases where your laboratory is not capable of testing for thrombin time.
If thrombin time (TT) can be measured and is within the normal range, then the drug is not therapeutic and reversal should not be carried out. The consensus statement recommends giving this drug if the TT is prolonged or your lab cannot measure it. Keep in mind that there are very, very few papers on DOAC reversal in trauma patients. Most studies address the stroke population, and this may not translate well to trauma. And there are no studies yet that show that idarucizumab offers any survival benefit if given.
Q2. Should prothrombin complex concentrate (PCC) always be given to patients who are taking Factor Xa inhibitors?
Answer: Only in cases where your laboratory is not capable of testing for anti-Xa activity.
If anti-Xa activity can be measured (in a timely manner) and is low, then the drug is not therapeutic and PCC need not be given. If the level is high or your lab cannot test for it, then the group recommends administering PCC if the specific reversal agent (Andexxa) is not available.
As with dabigatran above, there is very little trauma literature to justify this recommendation. Furthermore, Andexxa is very expensive and, like idarucizumab, has not been shown to improve survival. Next week, I’ll write about why Andexxa is probably not worth the cost, in my opinion.
Q3. Should DOACs always be reversed in hemorrhagic TBI?
Answer: We don’t know.
As I just mentioned, there is little if any data showing that administration of a reversal agent is beneficial. And the decision to give it must be balanced with patient risk for thrombosis and consideration of any other agents they may be taking. Expert opinion suggests that DOACs need not be reversed in TBI without blood on the CT scan, patients with unilateral, asymptomatic chronic subdural hematoma, and those with other wounds that do not appear to be bleeding excessively.
Hopefully, this series has helped shine some light on a confusing set of problems. Next week I’ll dig a bit deeper into the DOAC reversal agents Praxbind and Andexxa.
Reference: Diagnostic and therapeutic approach in adult patients with traumatic brain injury receiving oral anticoagulant therapy: an Austrian interdisciplinary consensus statement. Crit Care 23:62, 2019.
In my last post, I reviewed a large prospective series comparing smaller (28-32 Fr) to larger (36-40 Fr) chest tubes for management of pneumothorax. The authors did not detect any significant difference because the study was underpowered given the incidence of the adverse events examined.
Today, I’ve chosen a more recent paper that attempts to do the same thing. Interestingly, it cites the previous paper as a good example showing no differences! This one is from an emergency medicine group in Fukui, Japan. It is a retrospective review of seven years worth of patients who had a chest tube inserted for hemothorax only.
Here are the factoids:
- Small bore tubes were 20-22 French, and large bore tubes were 28 French (huh?)
- The tube selection was made (once again) at the discretion of the attending physician
- Demographics and injury data from the two groups were equal
- A total of 124 tubes were placed in 116 patients, 68 small bore and 56 large bore
- Empyema occurred in 1% in each group
- Retained hemothorax occurred in 2% of small tube patients and 3% of large tube patients
- An additional tube was placed in 2% of small tube patients and 7% of large tube patients (p = 0.41)
- Pain was not evaluated
The authors concluded that “emergent insertion of the small-bore tubes had no difference in efficacy of drainage, complications or need for additional invasive procedures.”
Bottom line: Huh? Once again we have an inferior design (retrospective review) and huge potential for selection bias (no criteria or randomization for tube size). But in this case, the tube sizes are very similar! The difference in diameter between a 20 Fr tube and a 28 Fr one is only 2.5mm! Reason #1 for no apparent differences.
For reason #2, look at the sample size. First of all, this hospital placed only 124 tubes in 7 years. That’s a one tube every three weeks. Is there that little chest trauma, or is a chunk of data missing? This sample size is less than half of that in the previous post, so the statistical power is far weaker. Look at the stats above for additional tube placement. A 3.5x change was not even close to being statistically significant. In fact, this sample size would not show a significant difference for retained hemothorax until one group had nearly 8x the number! No wonder the authors assumed there was no difference. The study was not designed in such a way that it could ever show one!
So throw this study in the trash bin, too. I’ll continue my search for a more convincing “size matters” paper in my next post.
And if you think you’ve got one, send it my way so I can have a look!
Reference: Small tube thoracostomy (20-22 Fr) in emergent management of chest trauma. Injury 48(9):1884-1887, 2017.
Spondylosis. Spondylolisthesis. Spondylitis. These words are tossed about blithely by our orthopedic and neurosurgical spine colleagues. But many trauma professionals are confused by the terms. What do they mean? What do they look like?
Let’s start with the root of the word, spondylo… This part is derived from the Greek word spondylos, meaning spine. Now let’s combine it with some of the usual suffixes.
The first one is -osis, so this creates the word spondylosis. Although -osis can denote the “condition of being a …”, in medicine it frequently means a disease or pathological process. Think diverticulosis of the colon. Spondylosis usually denotes a degenerative process of the spine. This is typically due to arthritis and results in bone spurs and disc narrowing. Here is an image of a spine with significant spondylosis:
Now let’s add -listhesis. This is another Greek word that means “slipping or falling.” So in this case, the full word means one vertebra slipping over another. Here’s an image of an anterior spondylolisthesis:
Finally, let’s add -itis. This is the Greek suffix for inflammation. So spondylitis is an inflammatory process of the spine. This can be due to infectious or autoimmune causes. One of the more common types is ankylosis spondylitis, which is an autoimmune variant of rheumatoid arthritis. This causes inflammation of the facet joints and the stabilizing ligaments, leading to fused vertebra and a characteristic patient posture. Here’s a rather extreme case:
I hope this little vocabulary lesson has been helpful. Now go impress your spine specialty colleagues!
Deer hunting season is upon us again in Minnesota and Wisconsin, so it’s time to plan to do it safely. Although many people think that hunting injuries are mostly accidental gunshot wounds, that is not the case. The most common hunting injury in deer season is a fall from a tree stand.
Tree stands typically allow a hunter to perch 10 to 30 feet above the ground and wait for game to wander by. They are more frequently used in the South and Midwest, usually for deer hunting. A study by the Ohio State University Medical Center looked at hunting related injury patterns at two trauma centers.
Half of the patients with hunting-related injuries fell, and 92% of these were tree stand falls. Only 29% were gunshots. And unfortunately, alcohol increases the fall risk, so drink responsibly!
Most newer commercial tree stands are equipped with a safety harness. The problem is that many hunters do not use it. And don’t look for comparative statistics anytime soon. There are no national reporting standards. No matter how experienced you are, always clip in to avoid a nasty fall!
The image on top is a commercial tree stand. The image below is a do-it-yourself tree stand (not recommended). Remember: gravity always wins!
Reference: Tree stands, not guns, are the midwestern hunter’s most dangerous weapon. Am Surg 76(9):1006-1010, 2010.