Rationale: Regionalization has been proposed as a method to improve outcomes for medical patients receiving mechanical ventilation in the intensive care unit.
Objectives: To determine the number of patients who would be affected by regionalization and the potential mortality reduction under a regionalized system of care.
Methods: We performed a retrospective cohort study with Monte Carlo simulation, using 2001 state discharge data from eight states representing 42% of the U.S. population. Adult medical patients undergoing invasive mechanical ventilation were identified. Patient location and hospital mortality rates were obtained from the discharge data; estimates of the relative risk reduction in hospital mortality for high-volume hospitals compared with low-volume hospitals were obtained from the published literature and applied to the cohort.
Measurements and main results: Of 180,976 adult medical patients who underwent mechanical ventilation at 1,170 nonfederal hospitals, 83,050 (46%) received mechanical ventilation at 887 (76%) hospitals with low annual volumes (fewer than 275 patients per year). Using published risk estimates, approximately 4,720 lives per year (95% range, 2,522-6,744) could potentially be saved in the 8 states by routinely transferring patients from low- to high-volume hospitals, representing a number needed to treat of 15.7. The median distance that patients would need to travel to reach a high-volume hospital was 8.5 miles (interquartile range, 4.0-21.2 mi).
Conclusions: Regionalization of intensive care could potentially improve survival for patients undergoing mechanical ventilation. Transfer distances are modest for most patients.