Use of critical pathways to improve the care of patients with acute myocardial infarction

PURPOSE: While critical pathways have become a popular strategy to improve the quality of care, their effectiveness is not well defined. The objective of this study was to investigate the effect of a critical pathway on proce sses of care and outcomes for Medicare patients admitted with acute myocard ial infarction. SUBJECTS AND METHODS: A retrospective cross-sectional and longitudinal coho rt study was made of Medicare patients aged 65 years and older hospitalized at 32 nonfederal Connecticut hospitals with a principal diagnosis of myoca rdial infarction during two periods: lune 1, 1992, to February 28, 1993, an d August 1, 1995, to November 30, 1995. The main endpoints of the cross-sec tional analyses for the 1995 cohort were the proportion of patients without contraindications who received evidence-based medical therapies, length of stay, and 30-day mortality. Hospitals with specific critical pathways for patients with myocardial infarction were compared with hospitals without cr itical pathways. The main endpoints of the longitudinal analyses were chang e between 1992-93 and 1995 in the proportion of patients receiving evidence -based medical therapies, length of stay, and 30-day mortality. RESULTS: Ten hospitals developed critical pathways between 1992-93 and 1995 , Eighteen of 22 nonpathway hospitals employed some combination of standard orders, multidisciplinary teams. or physician champions. Patients admitted to hospitals with critical pathways did not have greater use of aspirin wi thin the first day, during hospitalization, or at discharge; beta-blockers within the first day or at discharge; reperfusion therapy; or use of angiot ensin-converting enzyme inhibitors at discharge in 1995. The mean (+/- SD) length of stay in 1995 was not significantly different between pathway (7.8 +/- 4.6 days) versus nonpathway hospitals (8.0 +/- 4.2 days), and the chan ge in length of stay between 1992-93 and 1995 was 2.2 days for pathway hosp itals and 2.3 days for nonpathway hospitals. Patients admitted to critical pathway hospitals had lower 30-day mortality in 1995 (8.6% versus 11.6% for nonpathway hospitals, P = 0.10) and in 1992-93 (12.6% versus 13.8%, P = 0. 39), but the differences were not statistically significant. CONCLUSIONS: Hospitals that instituted critical pathways did not have incre ased use of proven medical therapies, shorter lengths of stay, or reduction s in mortality compared with other hospitals that commonly used alternative approaches to quality improvement among Medicare patients with myocardial infarction. (C) 1999 by Excerpta Medica, Inc.