All posts by TheTraumaPro

Carotid and Vertebral Artery Injury From Blunt Trauma

Blunt injury to the carotid or vertebral arteries (BCVI) is relatively uncommon, but potentially very deadly. Up to 2% of patients with high energy blunt trauma suffer this injury. Many are not diagnosed until the patient has ischemic symptoms or a stroke. However, more aggressive screening has shown a higher incidence that previously thought and may allow intervention before neurologic injury occurs.

Recently, a series of 222 patients with 263 BCVI was retrospectively reviewed, with an eye toward effectiveness of interventions. A total of 29 strokes occurred in the hospital in these patients, but only 7 of these occurred after diagnosis of the BCVI. Mortality was much higher in the stroke group (34% vs 7%). The authors looked at both medical and interventional therapies.

This paper identified the following items:

  • Car crash was the most common mechanism of injury (81%)
  • Vertebral arterial injury was slightly more common than carotid artery BUT
  • Women were much more likely to sustain a carotid injury
  • Older patients were more likely to have a vertebral injury

These authors found that CT angio was not sufficiently sensitive to identify all BCVI. They recommend a formal 4-vessel arteriogram in patients with a negative CT angio who have significant risk factors (unexplained neurologic deficit, Horner’s syndrome, LeFort II or III injury, cervical spine injury, soft tissue injury of the neck).

If a BCVI is identified, the patient should be heparinized until all other injuries are definitively managed. At that point, they should be preloaded with clopidogrel and aspirin and a repeat arteriogram should be performed. Endovascular stenting using a bare metal stent should be performed when possible because it results in the lowest stroke rate and requires the shortest duration of anti-platelet therapies. Patients then continue on aspirin and clopidogrel for an appropriate period of time.

To download the algorithm used by the authors, click here.

Reference: Optimal outcomes for patients with blunt cerebrovascular injury (BCVI): tailoring treatment to the lesion. J Am Coll Surg 212(4):549-559, 2011.

Predicting Bleeding In Patients With Stable Pelvic Fractures

Bleeding is a well-recognized complication of severe pelvic fracture. Certain fracture patterns, usually with significant involvement of the posterior portions of the ring, are associated with significant bleeding. Most of these fractures are unstable to some degree.

Stable pelvic fractures (those that do not require internal or external fixation) are not generally prone to a large amount of bleeding. However, it can occur on occasion, and surgeons at the Massachusetts General Hospital have devised a simple prediction system so patients more likely to bleed can be identified and monitored more closely.

They retrospectively looked at their stable pelvic fracture population over 5+ years. A total of 391 patients with stable pelvic injury were identified. Of those, 280 never required transfusion and 111 did. Of the latter, only 15 bled from their stable pelvic fractures. 

The authors found the following three significant indicators of bleeding from stable pelvic fractures:

  • Admission hematocrit < 30%
  • Pelvic hematoma on CT
  • Any systolic blood pressure < 90 mm Hg

Bottom line: This is a simple, retrospective study with low numbers. However, the three indicators commonly indicate significant early bleeding in any trauma patient, so it makes sense to apply it here, too. If a patient meets one or two criteria, consider monitoring in the ICU and consider angiography. If all three or met, strongly consider appropriate intervention (angiography if good blood pressures can be maintained, or fixation and/or preperitoneal packing if not).

Reference: Predictors of bleeding from stable pelvic fractures. Arch Surg 146(4):407-411, 2010.

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Technology: A New Teaching Tool For Orthopedic Injury

Here’s a look at some new technology (made from five pieces of old technology) to help injured patients follow their activity and exercise regimens better after injury. It allows patients to “look beneath the surface” of their injured extremity to get a better idea of what is wrong and why they need to be compliant to heal.

Microsoft Research Labs cobbled together a projection unit from a handheld projector, a digital camera and an infrared camera. The control unit consists of a wireless controller and a laser pointer. Put them together and you can superimpose stock injury images over a patient’s extremity, or review images on a wall.

Two physical therapists did an uncontrolled test on several patients and indicated that overall compliance with the therapy regimen seemed to be better. Obviously, this is not sound science. But it does have some potential in allow physicians and therapists to give a better explanation about what is injured and what needs to be done about it. In my opinion, this could be generalized to just about any internal injury, and can provide an easy to understand teaching tool for trauma professionals.

Anatomic injury projector

How To Troubleshoot Air Leaks in Chest Tube Systems

An air leak is a sure-fire reason to keep a chest tube in place. Fortunately, many air leaks are not from the patient’s chest, but from a plumbing problem. Here’s how to locate the leak.

To quickly localize the problem, take a sizable clamp (no mosquito clamps, please) and place it on the chest tube between the patient’s chest and the plastic connector that leads to the collection system. Watch the water seal chamber of the system as you do this. If the leak stops, it is coming from the patient or leaking in from the chest wall.

If the leak persists, clamp the soft Creech tubing between the plastic connector and the collection system itself. If the leak stops now, the connector is loose.

If it is still leaking, then the collection system is bad or has been knocked over.

Here are the remedies for each problem area:

  • Patient – Take the dressing down and look at the skin entry site. Does it gape, or is their obvious air hissing and entering the chest? If so, plug it with petrolatum gauze. If not, the air is actually coming out of your patient and you must wait it out.
  • Connector – Secure it with Ty-Rap fasteners or tape (see picture). This is a common problem area.
  • Collection system – The one-way valve system is not functioning, or the system has been knocked over. Click here for an example. Replace it immediately.

Note: If you are using a “dry seal” system (click here for more on this) you will not be able to tell if you have a leak until you fill the seal chamber with some water.

Medication Alert! Dabigatran and Head Trauma

First, there was warfarin, a cheap and effective way of treating deep venous thrombosis (DVT) and pulmonary embolism (PE) in trauma patients. Unfortunately, there is plenty of literature that shows the added risk that this drug poses in injured patients, particularly in head injury. Because of this, many trauma centers have developed “rapid reversal protocols” to quickly restore vitamin K dependent clotting factors in an attempt to improve outcomes. To see our protocol, click here.

Next came clopidogrel (Plavix), which is used to prevent clotting in vascular disease. It irreversibly inhibits platelet aggregation. Counteracting this drug is more complicated due to its long half-life. Platelet infusions are required, but the infused platelets are inhibited by any remaining drug in the plasma. This requires the use of lots of platelets to get some meaningful clot to form again.

Now, we have direct thrombin inhibitors (DTI). Hirudins were the first used, and were never an issue in trauma patients. And their short half-lives obviate the need for reversal. The newest DTIs (argatroban and dabigatran) are a real problem in trauma. Argatroban is not a problem, because it is given by IV only. But dabigatran (Pradaxa) has just been approved for oral use within the last year.

According to the package insert, “there is no antidote to dabigatran etexilate or dabigatran.” And also “dabigatran can be dialyzed (protein binding is low), with the removal of about 60% of drug over 2 to 3 hours; however, data supporting this approach are limited.”

We will be seeing patients taking this drug in the near future. What do we do if they are trauma victims with bleeding in critical places, like the brain? At Regions, we have developed a proposed guideline that combines oral charcoal, dialysis, transfusions and optionally, activated Factor VII. Click here to download the protocol.

If anyone has any experience with these patients, please comment below. And everyone else, keep your fingers crossed!

Related posts:

Protocols:

Thanks to Colleen Morton MD for developing the dabigatran reversal protocol