“Is This ECG Real Or Artifact?”

In the world of perioperative and intensive care medicine, I’m surrounded by continuous monitors; however, it’s important to understand how monitors work (and the pitfalls associated with them) before one interprets the numbers they provide. Since most monitors don’t understand the clinical context, they will alarm incessantly for predefined thresholds. This can lead to alarm fatigue and lack of attention to subtle findings that may in fact be real.

A question I often receive and have to determine myself in practice is whether or not an ECG strip “is real.” The patient sitting comfortably, watching TV and eating lunch, probably doesn’t have ventricular fibrillation (VFib). The patient who has had atrial fibrillation (AFib) her entire adult life probably didn’t spontaneously convert to normal sinus rhythm (NSR) during a clinic visit. But sometimes, these calls are tough to make! Here’s how I approach the “artifact vs. real ECG” dilemma:

1. Stop looking at the monitors and go see the patient. Ask him/her about any acute changes. Patients know their bodies, so listen! Unfortunately, this isn’t possible when my OR/ICU patients are under anesthesia or sedated, but I’d say it’s the single most important tip.
2. Palpate the pulse. Is it strong? Is it (ir)regular?
3. Change the monitored lead, ECG pads, and/or monitor (ie, use a portable monitor). Get a 12-lead ECG.
4. Cross-check with another monitor. For example, a regular arterial line interval or a normal heart rate on a pulse oximeter can be reassuring.
5. Use a bedside ultrasound to look at the heart’s actual movement in real-time.
6. Does the arrhythmia make sense in the clinical context (ie, AFib after an esophagectomy, persistent electrolyte or acid-base derangements, etc.)
7. There is NO SHAME in asking for help or a second opinion.

Acting on a monitor can have severe consequences if the reading is erroneous. It’s important to consider patient-centered factors (e.g., symptoms, overall clinical context) before addressing or ignoring every alarm.

Drop me a comment with your thoughts!