Clinical Editor's Corner

The STEMI Box– Shorten D2B and Cath Lab Prep in the Emergency Department

Morton Kern, MD Clinical Editor Professor of Medicine Associate Chief Cardiology University of California Irvine Orange, California
Morton Kern, MD Clinical Editor Professor of Medicine Associate Chief Cardiology University of California Irvine Orange, California
(Note: Please visit to read this month's "Letters to the Clinical Editor." The letters missed the March print edition and will be published in the April edition). There is no doubt that the national initiative to save lives by reducing the time to reperfusion in the acute myocardial infarction patient is working and in full swing for STEMI receiving center cath labs. Reducing the door-to-balloon time (D2B) has been discussed in Cath Lab Digest almost every other month for many years. CLD strives to inform, train, demonstrate, and encourage all parties involved to shorten D2B times. Multi-center studies and even some single-center studies reinforce the benefit of streamlining the process of moving the patient from his home through the emergency department (ED) to the cath lab for angioplasty. The American Heart Association has educated the community in an effort to shorten the time it takes for the patient to recognize symptoms and call EMS. The evaluation of the patient by EMS has been shortened in some centers with transmission of the ECG by fax, phone or email, and activation of the cath lab from the field. However, most of the time, the patient arrives in the ED with a preliminary ECG and once through the door, the clock starts ticking. An analysis of our facility’s D2B times demonstrated inconsistent achievement of our 90-minute goal. A quality review process demonstrated where and why we were not meeting our D2B time. It showed us two bottlenecks causing procedure delays. One place was the time in the ED until transfer to the cath lab and the other was a somewhat variable time for the cath lab to prep the patient, since some of the prep time was used in cath lab nurse arrival time. (The call team lives 30-45 minutes away.) Once in the cath lab, the time to access the circulation and enter the infarct-related artery was generally not a concern. Here’s where our nurses helped shorten the transit through the ER and cath prep. The cath lab nurses and technologists came up with a way to shorten the prep time in the cath lab, one I think is worth sharing. They invented the STEMI box. The STEMI box is a large plastic box, like a fishing tackle box, which contains 1) forms for documentation, consent, and education, and 2) supplies needed for the patient to help the cath lab shorten preparation time. The forms are an ER STEMI nursing checklist, EMS STEMI report form, consent form, conscious sedation record form, and STEMI education booklet. The STEMI box supplies include a cath lab gown, two long IV extension tubings, translucent ECG leads (x10), and translucent defibrillator pads. We have two STEMI boxes, one in the ER and another in the cath lab. When the STEMI patient arrives from the ED with the STEMI box, a new STEMI box is given to the ED nurses to take back to the ED after they deliver the patient to the lab. The cath lab restocks the STEMI box each time it is used, and keeps it ready to be traded for the one in use. Where does the 90 minutes of the D2B time go? The STEMI receiving center process begins with a call from EMS to the ED, informing the ED that they are bringing a STEMI patient. The ED activates the cath lab by calling the hospital operator. The operator pages the cath lab call team and everybody heads into the hospital. At this time, most hospitals do not have in-house cath lab call teams. In the ED, the ECG is confirmed as a STEMI, and ED nurses proceed to evaluate the patient, begin ECG and pressure monitoring, insert another IV line and administer medications as needed. Stabilization and documentation consume most of their time. In our system in years past, there was a delay caused by prolonged ED evaluation, with a hold-up of transfer by nurses completing their notes before moving the patient upstairs. This is no longer the case and in fact, this was one of the two changes that dramatically shortened patient time in the ED. The first remedy was to institute a “no-hold” in the ED for any reason once the cath lab was ready. Giving the STEMI box to the ED nurses also made the process shorter by providing the right paperwork at hand with the IV lines and ECGs plus defib patches ready to go. While this doesn’t sound very time-consuming, all cath lab nurses and techs appreciate the fact that transferring a critically ill patient from a stretcher to the x-ray table is very difficult when the IV lines are tangled or too short. The IV is the patient’s lifeline. The step of ensuring that the IV line is functional cannot be skipped. The same can be said about lucent ECG leads and defib pads. Changing ECG leads takes 3-4 minutes, adds unnecessary delay and some degree of frustration. In our lab, the STEMI box has eliminated this problem. Exactly how much time should each of the transition points in the STEMI D2B process take? Bradley et al discussed exactly how successful hospitals achieve D2B times that meet quality guidelines.1 This paper is revealing and should be required reading for all STEMI programs. I extracted a figure from this article to show us where the time goes (Figure 1). After the patient arrives to the door of ED, the ED physician uses 8 minutes to review the ECG and diagnoses STEMI. The ED activates the cath lab over the next 5 minutes. The ED then uses another 30 minutes to stabilize the patient. After activation, it is estimated that the cath lab arrival time should be 20 minutes to the hospital and cath lab set up time will be another 20-30 minutes. ED transport to cath lab takes 5 minutes. In the cath lab, there are an additional 5 minutes to check the consents, transfer the patient, and 10 minutes to prep and drape the patient. The cath lab operators then use another 20-25 minutes for access, coronary angiography and angioplasty guidewire passage to stop the STEMI clock. Total time from ED door to vascular access is 60 minutes, with 30 minutes to cross the lesion, achieving the goal of D2B in less than 90 minutes. What if we don’t make the D2B time? While a highly desirable goal, making the ideal D2B time is not always possible. More importantly, there may be occasions when the rush to achieve the 90-minute D2B time might be harmful, should the patient’s condition require more stabilization before catheterization. The 90-minute D2B time should be a guide, not a law. Patient care should never be compromised to achieve the D2B time, especially when the patient needs stabilization, reassessment, new diagnosis and appropriate treatment. All of these actions may require more time than is planned. Managing hypotension, arrhythmias, heart block, vomiting, hypoxia, and the patient’s mental status require more time, pushing the D2B time to or beyond its limit. No patient care should be sacrificed in order to meet that D2B time. Always remember that ‘safety first’ is especially true for the STEMI patient. If you need time to insert a pacemaker or intra-aortic balloon pump (IABP), or begin dopamine before entering the infarct artery, take the time to do it right. The STEMI box can save 5-10 minutes or more, and was a great invention from our cath lab nurses and techs which is now widely employed by the ED nurses. The time in the ED and cath lab prep time has been reduced, and we are making our 90-minute number more than 85% of the time. The old cliché, “Necessity is the mother of invention,” is true and there is no better group than the cath lab team to invent aids to help their patients before, during and after the cath lab visit. Dr. Kern can be contacted at References 1. Bradley EH, Roumanis SA, Radford MJ, et al. Achieving door-to-balloon times that meet quality guidelines: how do successful hospitals do it? J Am Coll Cardiol 2005 Oct 4;46(7):1236-1241. 2. Berger PB, Ellis SG, Holmes Jr. DR, et al. Relationship between delay in performing direct coronary angioplasty and early clinical outcome in patients with acute myocardial infarction: Results from the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes (GUSTO-IIb) trial. Circulation 1999;100:14-20. 3. Cannon CP, Gibson CM, Lambrew CT, et al. Relationship of symptom-onset-to-balloon time and door-to-balloon time with mortality in patients undergoing angioplasty for acute myocardial infarction JAMA 2000;283:2941-2947.