The primary purpose of the prehospital 12 lead ECG is to detect acute coronary ischemia or injury in the prehospital setting.
That's not to say it's the only purpose for a prehospital 12 lead ECG, but it's the main reason we carry 12 lead monitors on the ambulance!
Ideally, the early identification of STEMI patients will:
- Ensure delivery of STEMI patients to facilities capable of performing prompt, expertly performed primary PCI (regional systems of care).
- Shorten door-to-balloon (D2B) times by enabling parallel processing, or early activation of the cardiac cath lab, especially during off-hours (nights, holidays, weekends) or anytime the cath lab isn't staffed 24 hours/day.
I'll start with my top 10, and open it up for discussion.
1.) Chest pain or discomfort – In my opinion, any unusual sensation, nose to navel, front or back, qualifies. This will ensure that you cast a wide net and pick up on lots of atypical presentations.
2.) Shortness of breath – I ask all chest pain patients about shortness of breath (many admit to mild dyspnea even with normal respiratory rates and clear breath sounds), and I ask all shortness of breath patients about chest pain. Both get a 12 lead ECG regardless. Be especially mindful of new exertional dyspnea, particularly in the elderly patient, and acute pulmonary edema.
3.) Syncope or near syncope – Let's face it, a lot of our syncope patients end up refusing transport to the hospital, but a small subset are at high risk for sudden death! Capture a 12 lead ECG and review it for ACS, arrhythmias, a prolonged QT/QTc, signs of hypertrophic cardiomyopathy, or Brugada's Syndrome.
4.) Diaphoresis unexplained by ambient temperature, unexplained general weakness, or unexplained nausea and vomiting. Be especially suspecious if your patient is a diabetic.
5.) Suspected diabetic ketoacidosis (which may be an atypical presentation of ACS).
6.) A feeling of impending doom – Often a patient just knows something is frightfully wrong! Usually accompanied by diaphoresis unexplained by ambient temperature.
7.) Any suspected drug overdose or metabolic derangement. Be especially alert for dialysis patients who present with general weakness and/or shortness of breath!
8.) An unconscious patient (excluding cardiac arrest). On the other hand, it's one of the first things you want to accomplish when your patient experiences ROSC.
9.) Palpitations – Defined as any uncomfortable awareness of your own heart beat. Includes "skipped" beats and "racing" heart.
10.) Any heart rate less than 50 or greater than 150.