Transporting emergency services' patients with ST-segment myocardial infarction only to those hospitals that already have percutaneous coronary intervention capability increases access to the procedure and is much more cost effective than constructing new or expanding existing PCI centers and staffing them, according to a computer-simulated study.
“Our results strongly suggest that construction and staffing of new PCI [facilities] may not be warranted if an [emergency medical service] strategy is both available and feasible,” wrote Thomas W. Concannon, Ph.D., of the Center for Cardiovascular Health Services Research, Tufts Medical Center, Boston, and his associates.
The researchers used mathematical modeling to compare the benefits and costs of various approaches for improving patient access to PCI. “We simulated EMS transport, reperfusion strategy, clinical outcomes, and costs for 2,000 patients, representing approximately 1 year of STEMIs in a municipal area the size of Dallas County, Texas.” This region comprises an ethnically diverse population in urban, suburban, and rural areas.
The models incorporated predicted rates of post-MI stroke, congestive heart failure, reinfarction, and mortality at 30 days and 6 months.
The investigators compared outcomes between a strategy in which EMS providers transported patients only to existing PCI-capable hospitals and another in which EMS providers transported patients to the nearest hospital, regardless of PCI capability. They assessed 13 scenarios in which either hospital PCI capability was constructed from scratch or existing PCI services were expanded incrementally (for example, from part-time to full-time operating hours, from basic to fuller staff coverage, and from providing no backup coronary artery bypass surgery suite to providing an on-site CABG suite).
All models increased patient access to PCI. However, the strategy in which patients were taken only to hospitals with PCI capability was by far the best, allowing 1,391 of the 2,000 patients to receive PCI, the investigators wrote (Circ. Cardiovasc. Qual. Outcomes 2010 [doi:10.1161/CIRCOUTCOMES.109.908541]).
This strategy also was the most cost effective, with a cost per quality-adjusted life-year (QALY) saved of $506.
In comparison, the most cost-effective of the 13 hospital-based scenarios—to expand existing part-time PCI centers within the two highest-volume hospitals so that they had on-call staff covering nights and weekends—allowed only 913 of the 2,000 patients to receive PCI, at a cost per QALY saved of $10,000.
The remaining scenarios increased the number of patients who received PCI to varying degrees, but did so at much higher costs of up to $85,000 per QALY saved.
None of these models explored an approach in which the STEMI patients were stratified so that only those most likely to benefit from PCI would be diverted to PCI-capable hospitals. “We believe an even stronger case could be made for a strategy that involves selective transport of only those patients who are individually predicted to benefit,” Dr. Concannon and his associates said.
“Our results suggest that regional planners should consider EMS strategies for increasing access to PCI before adopting strategies involving new construction or increased staffing of PCI hospitals,” they said.
This study was supported by the Agency for Healthcare Research and Quality; the National Heart, Lung, and Blood Institute; and a Tufts Medical Center-Pfizer career development award. No conflicts of interest were reported.