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 processes of care and outcomes for Medicare patients admitted with acute myocardial infarction.
Subjects and methods: A retrospective cross-sectional and longitudinal cohort study was made of Medicare patients aged 65 years and older hospitalized at 32 nonfederal Connecticut hospitals with a principal diagnosis of myocardial infarction during two periods: June 1, 1992, to February 28, 1993, and August 1, 1995, to November 30, 1995. The main endpoints of the cross-sectional 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 critical pathways. The main endpoints of the longitudinal analyses were change 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 within the first day, during hospitalization, or at discharge; beta-blockers within the first day or at discharge; reperfusion therapy; or use of angiotensin-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 change in length of stay between 1992-93 and 1995 was 2.2 days for pathway hospitals 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 increased use of proven medical therapies, shorter lengths of stay, or reductions in mortality compared with other hospitals that commonly used alternative approaches to quality improvement among Medicare patients with myocardial infarction.