The persistent discrepancy between the door-to-balloon times of on-hours versus off-hours in STEMI patients undergoing PCI procedures can be solved through cost-effective means; however, some argue that an expensive and complex pre-activation program is needed to bring off-hour times in line with those of on-hours.
Early in 2006, the American College of Cardiology (ACC) recognized the urgent need to reduce door-to-balloon times for patients experiencing ST-segment elevation myocardial infarction (STEMI). In June of that year, the college began building the D2B Alliance, a nationwide network of hospitals, physician champions and strategic partners committed to addressing the door-to-balloon challenge.
However, recent clinical data has confirmed what many cath lab directors already knew—door-to-balloon times are much longer for patients on weekends and after regular hours, often defined as “off-hours.” As a result, many systems and methods have been recommended and implemented to improve this disparity. While several components contribute to this difference in performance, a consistent obstacle seems to be the speed in which the cath lab can be staffed.
“When a patient presents off-hours, the hospital is typically at a reduced staffing level across all departments, which affects how a patient is initially managed and how the cath lab gets activated,” says Brahmajee Nallamothu, MD, a professor in the department of internal medicine at the University of Michigan in Ann Arbor. “We are seeking certain hospital-based, cost-effective procedures that could shorten the time for treatment of STEMI patients. Although it is still under investigation, ED activation and using a single-call system, as well as a pre-hospital ECG system, could serve to better treat these patients in the off-hours.”
The D2B Alliance, led by Yale University epidemiologist Elizabeth H. Bradley, MD, recommended four strategies for reducing door-to-balloon times, regardless of presentation hour (NEJM 2006;355:2308-2320):
- Emergency department physician activates the cath lab;
- Single call to activate the cath lab;
- Cath lab operational within 20-30 minutes of activation; and
- Real-time data feedback for case review.
While these four strategies are quite effective for reducing on-hour door-to-balloon times, hospitals most likely can not eliminate the off-hour discrepancy by just implementing these four strategies, notes Henry Ting, MD, vice-chair of the division of cardiovascular disease at the Mayo Clinic College of Medicine in Rochester, Minn.
Bradley and colleagues also suggested two additional strategies, but less forcefully, because they could prove costly to a hospital:
- having an attending interventional cardiologist always present in the hospital,
- and installing a pre-hospital ECG to activate the cath lab while the patient is en route.
Even for the busiest of U.S. hospitals with 300 to 400 STEMI patients a year, it would be difficult to financially justify staffing an interventional cardiologist, plus the entire cath lab team in-house, 24/7, according to Ting. “Economically, it is a very expensive endeavor to incur for potentially 150 STEMI patients a year.”
Frank V. Aguirre, MD, of the department of internal medicine and interventional cardiology at Memorial Medical Center in Springfield, Ill., initiated in 2001 the four main strategies outlined by Bradley et al. The hospital quickly demonstrated a significant reduction in door-to-balloon times, but still had a “serious discrepancy” in its off-hour versus on-hour times. Approximately, 60 percent of STEMI patients in the U.S. present in off-hours.
To combat the problem, Memorial Medical Center, which performs an estimated 75 PCI procedures on STEMI patients yearly, adopted two other methods. First, it cross-trained the ED nurses to initiate the cath lab process before the cath lab nurses come into the hospital. Second, Aguirre adjusted working hours so some cath lab personnel began their shift about five hours later, essentially eliminating some of the unstaffed off-hours.
“By adopting these additional tactics, we further decreased the overall door-to-balloon times by 11 percent. By 2007, our overall median door-to-balloon time was 58 minutes and our off-hour door-to-balloon time was 57 minutes,” Aguirre says.
ECG with the EMS
While a pre-activation ECG is a sure-fire method of reducing door-to-balloon times, it is not necessarily the most economical. On average, a pre-activation ECG device costs the