A 50-year old man with no known medical history (“I don’t see doctors. I don’t like doctors.”) presents to the ED because he crashed his car into a pole after driving after a “wintry mix” weather event (#blizzard2015). There was no loss of consciousness. Airbags deployed. The car sustained damage to the bumpers and one window broke. He complains primarily of chest pain. Vitals are normal and his exam is unimpressive other than mild bruising on the upper left chest where the airbag hit him.
On cross-examination, he admits he had chest pain immediately *before* he crashed the car, which leads you to order an ECG. It shows a slam-dunk ST-elevation Myocardial Infarction (STEMI) of the lateral territory.
The remainder of his trauma exam is normal (normal head and neck, normal neurological exam, heart, lungs, and abdomen clear, no other deformities or skin changes). Due to the mechanism of the accident, you do not clear his c-spine (collar in place).
Free pearl: Get a good history on trauma patients. ST-elevation myocardial infarction (STEMI) can cause a motor vehicle accident!
But what if, WHAT IF, the patient only had pain after the accident?
What screening is necessary for ruling out Blunt Cardiac Injury? ECG? Troponin? Echo? CT coronary? MRI? Admission?
Do sternal fractures impact your testing thresholds?
According to the Eastern Association for Surgery of Trauma guidelines (2012), all patients at risk for blunt cardiac injury (high energy mechanism traumas including MVC, fall from height, pedestrian struck, sports injury) should have a 12-lead ECG (Level I recommendation) and a troponin (Level 3 recommendation). If the ECG is normal or unchanged, and the troponin is normal, no further evaluation is required for ruling out blunt cardiac injury.
Patients with abnormal ECG findings that are new (arrhythmias, ST changes, ischemic pattern, heart block) and/or a positive troponin assay should be admitted to the hospital in a monitored setting.
Echocardiograms are not recommended as an effective screening tool for blunt cardiac injury in hemodynamically stable patients. If unstable, a trans-thoracic echo (TTE) should be attempted; if insufficient, a trans-esophageal echo (TEE) should be obtained. Cardiac CT or MRI can be used to distinguish myocardial infarction from blunt cardiac injury.
Sternal fractures should not change pre-test probability for blunt cardiac injury
References:
Clancy K et al. Screening for blunt cardiac injury: an Eastern Association for the Surgery of Trauma practice management guideline.
J Trauma Acute Care Surg. 2012 Nov;73(5 Suppl 4):S301-6. doi: 10.1097/TA.0b013e318270193a.
Thanks to Dr. Hexom and Dr. Nassisi for input on this case!
