Nothing gets your heart racing like bradycardia. Wait, that sounds backwards. How about, “Nothing makes you as diaphoretic as your patient like unstable bradycardia does.” That’s better.
On a recent episode of FOAMcast, we dove into some of the various approaches to the patient with a slow heart rate who isn’t looking well. Of course, because our mission is to bridge the world of Free Open Access Medical education (FOAM) to core content and the peer-reviewed literature, we looked at a number of FOAM resources on the topic, compared that to material in our most cherished textbooks, and then checked out some articles on PubMed. Usually, the criticism of FOAM is that it is more “cutting-edge” and “aspirational” than what you would find in reality. However, we found the peer-reviewed papers more out of touch with reality than the FOAM.
Specifically, there seems to be little to no disagreement on when to emergently pace bradycardic patients. Are patients hemodynamically unstable or worrisomely symptomatic? Do they have a high-degree AV block? Do they have sick sinus syndrome? We’re all on the same page; pace these patients!
The controversy is how to emergently pace. First, should transcutaneous pacing even be attempted? According to a lecture by Joe Bellezzo, MD, FACEP, featured on the Ultrasound Podcast (@ultrasoundpod), subtly titled, “Transcutaneous Is Just Stupid,” the answer is no. Why? First, he argues, it works less than half of the time, with a 40 percent capture rate. Additionally, patients are often diaphoretic or are sticky with nitroglycerin paste, the procedure is painful, most sedatives you would use—other than ketamine—might cause additional hypotension, and finally, the artifact from the transcutaneous pacer might mask ventricular fibrillation. An informal poll of a handful of other FOAM thought leaders revealed to us that, while he may be right that these are setbacks, transcutaneous pacing is an important adjunct while setting up for the sterile placement of the transvenous pacemaker. Placing a transvenous pacer, we are told by Dr. Bellezzo, should only take about six minutes, including setting up, getting sterile, placing the line, floating the pacer, and securing the setup.
Six minutes? We can just hear all the old-timers yelling out, “That’s ridiculous and impossible!” The next thing you know, my residents are going tell me that they heard on some fancy podcast that a transvenous pacemaker only takes six minutes to perform!
Here’s the problem, and don’t blame FOAM. Dr. Bellezzo cited the peer-reviewed literature when he quoted this number.1 Meanwhile, a previous study gave the somewhat more realistic estimate of 18 minutes.2 In reality, we all know that this procedure takes somewhere between 15 and 45 minutes, depending on a number of complexities. Just to make sure we weren’t crazy, we informally polled a handful of critical care emergency physicians. They told us we are correct about our estimate of the timing. For example, Al Sacchetti, MD, FACEP, has a video demonstrating the placement of a transvenous pacemaker (find it on YouTube) that lasts around 10 minutes, but in the video, he and his assistants are already sterile and draped. Also, the video ends before they suture the lines in place and clean up—and he is Al Sacchetti, and we most definitely are not. Where do Tintinalli and Rosen stand? Tintinalli’s Emergency Medicine says that a drawback to transvenous pacemaking is that it is “time consuming,” and by that we don’t think they mean six minutes. Rosen’s Emergency Medicine mentions both transcutaneous and transvenous pacing as options but does not weigh in on the timing.