Case Study: Pradaxa

Case Study

The Franktown Fire Protection District (FFPD) provides service to 155 square miles in unincorporated Douglas County, CO. A combination full-time paid and volunteer agency, FFPD provides BLS and ALS services to its citizens.

At 11:44 a.m. on a warm, summer day, the FFPD is called to a two lane winding road for a “tractor accident with injuries.” Upon arrival, crews discover a 61-year-old male standing in the front yard, learning forward against an overturned riding lawnmower. The scene is secure and safe. Crews are greeted by a woman identifying herself as the man’s wife, who tells them her husband was mowing the lawn when he drove too close to the edge of a retaining wall on the tiered lawn. The riding mower rolled over, fell approximately 5 feet and landed approximately 10 feet away from the base of the wall. Furthermore, the wife states the mower “rolled over” the patient. She claims her husband was unconscious for approximately 30 seconds.

Assessment

The patient is alert and oriented. Even before reaching him, there are injuries visible from several feet away. He is not wearing a shirt, and a deformity to his right posterior ribs directly below the scapula is noted. His wife insists this is new, while he argues the deformity is an old one. He does, however, complain of pain in his back, midline at T6–T8 as well as L2–L4. His skin is pink, warm and diaphoretic. Pupils are equal and reactive. Lungs are clear and equal bilaterally. He is on home oxygen at 2 l/m. He tells providers he had a cardiac ablation, cardioversion and a stent placed one week ago. His wife retrieves the patient’s list of medications from the house. They include: hydrochlorothiazide (HCTZ), Lisinopril, Norvasc, Digoxin, Lasix, Cialis and Pradaxa. The patient is allergic to codeine.

Prehospital Care

Since the patient is standing, the decision is made to board him standing and then lay him down. Every available blanket, sheet and towel is taken off the ambulance to provide ample padding around the deformity and to fill in void spaces. A cervical collar is applied, and he is tilted back and brought to the ground. Head blocks are ineffective because of all the padding, so a blanket rolled into a horseshoe shape is used to stabilize his head. Final packaging is done, and the patient is loaded into the ambulance. Then, he is transported emergent to the nearest trauma center.

Initial vital signs are as follows: BP = 158/118, P = 72, RR = 20, blood glucose = 131 mg/dl, pulse ox is 99% on 15 l/m O₂. Prehospital treatment includes a large bore (14g) IV, EKG monitoring and continually reassessing the patient from head to toe. Two minutes from the hospital, he begins to complain about leg numbness. He is brought into the emergency department and care is transferred to the trauma team.

ED Assessment

BP = 112/72; P = 84, RR = 32, temp = 93.4; pulse ox is 95% on 4 l/m of O₂. Lung sounds are equal bilaterally with no obvious rales. No subcutaneous emphysema is noted. Although there is an increase in respiratory rate, the patient states he has post-polio syndrome and takes shallow respirations normally. The patient states there is tenderness upon palpation at the base of the ribs bilaterally. A chest x-ray appears normal, with no consolidation or effusion present. No signs of a hemothorax or pneumothorax were found.

The patient is sent for a CT of the head and spine, which are both negative. However, a CT of the abdomen and pelvis reveals a burst fracture of T-11, T-12 and L-1, as well as non-displaced fractures of ribs 5, 6 and 9 on the right side. It’s determined that a right-sided comminuted scapular fracture is also present. Further imaging tests reveal a possible hemothorax posterior to the right lung.

Upon returning from CT the patient’s blood pressure drops precipitously, and is now in the upper 80s. Another large bore IV is established and volume replacement is initiated.

After transfer to the ICU, the patient’s hypotension becomes more acute, falling into the low 70s. It’s decided to transfuse two units of blood, followed by an additional four units of packed red blood cells, as the patient’s hematocrit has fallen precipitously (from 13.3 upon admission to 8.8).

Complicating matters is the fact that this patient was recently placed on Pradaxa as a result of his ablation and stent placement the week before. A consult with trauma services and pharmacy leads to a phone call with Boehringer-Ingelheim, the manufacturer of the drug. It’s learned that no reversal agent exists for Pradaxa. Short of dialysis, or simply waiting for the drug to metabolize out of the patient’s system on its own, there’s no documented way to reverse its affects.

Subsequently, the patient is given two units of fresh-frozen plasma and 5 mg of vitamin K intravenously. Profilnine (factor IX complex) is obtained from a neighboring hospital and also administered to the patient.

After the patient’s blood pressure stabilizes, a repeat CT of the right lung reveals the existence of a large hemothorax, requiring placement of a chest tube and the evacuation of 2.5 liters of blood—2 liters of which are autotransfused back into the patient.

Making this case even more challenging, prior to placement of a chest tube the patient experiences two episodes of supraventricular tachycardia (SVT), causing his blood pressure to drop into the 50s during each event. Each episode resolves spontaneously without the need for interventional medications or cardioversion.

Hospital Course

Once the patient is deemed stable he undergoes surgery to repair the trauma-related injuries to his back. A partial laminectomy, medial facetectomy and foraminotomy of T-9 thru L-2 are performed with no complications. The patient is discharged to a rehabilitation facility 10 days later. Three months later, the patient visits the FFPD station to thank the crew for taking care of him.

He also asks if anybody wants to buy a used—and banged up—riding lawnmower.

Pradaxa and the Multi-System Trauma Patient

Pradaxa (dabigatran etexilate) is an oral anticoagulant from the class of the direct thrombin inhibitors. It is primarily used to prevent blood clots and reduce the risk of stroke in people with atrial fibrillation not caused by valve disease or defect.

The U.S. Food and Drug Administration (FDA) approved Pradaxa on Oct. 19, 2010, for prevention of stroke in patients with nonvalvular atrial fibrillation. For millions of heart patients, this marked the first time there was an alternative to Coumadin (warfarin) in more than 60 years. In less than one year on the U.S. market, pharmacies dispensed approximately 1.1 million Pradaxa prescriptions to patients.

Pharmaceutically, these two drugs differ greatly (Figure 1). Pradaxa is a direct thrombin inhibitor, (i.e., it prevents formation of blood clots by blocking the production of thrombin). Warfarin is a vitamin K antagonist (i.e., it stops clots by directly interfering with vitamin K). The benefit to the patient is there’s no longer a need for monitoring. With Pradaxa, there is no need for regular blood tests to see if your blood-thinning level is in the right range. However, when you take Coumadin, you need to have a regular blood test to measure international normalized ratio (INR) to determine the time it takes for your blood to clot. Unlike Coumadin, there is no specific way to reverse the anticoagulant effect of Pradaxa in the event of a major bleeding event.

Since Pradaxa keeps your blood from coagulating to prevent unwanted blood clots, this medicine can also make it easier for you to bleed—even from a minor injury, such as a fall or a bump on the head.

It’s important to note that medications having similar anticoagulation properties as Pradaxa—such as Xarelto (rivaroxaban)—are becoming more commonplace in medicine. Like Pradaxa, Xarelto currently has no mechanism of reversal other than time, which creates challenges for healthcare providers treating trauma patients.

Lessons Learned

For FFPD personnel, a key take-away lesson from this case was to perform a thorough patient history on all patients respective to the medications they may be taking. Although eliciting a history of Pradaxa use would not alter prehospital treatment for trauma patients, it does provide the receiving facility or trauma center with key information on how to treat the multi-system trauma patient they’re about to receive.

In fact, it’s quite possible the receiving facility may not even be aware of the difficulties associated with reversing the effects of Pradaxa. Awareness and education of the hospital staff by field personnel may be the single, most important benefit of identifying patients taking these new types of anticoagulants early on in the course of the prehospital assessment.

Bryan Kendall is a paramedic/firefighter at Franktown (CO) Fire Protection District. He has been in EMS since 1992 and has been a paramedic since 1998.