The introduction of basic critical care echocardiography reduces the use of diagnostic echocardiography in the intensive care unit

Abstract

Background: Basic critical care echocardiography (CCE) is routinely used by intensive care unit (ICU) providers to rapidly address key hemodynamic questions for the critically ill. By comparison, diagnostic echocardiography (DE) uses a comprehensive examination with more traditional workflow and sophisticated techniques. Despite these differences, both are frequently used to answer similar questions in ICU. This overlap raises questions of duplicate testing and redundancy of hospital resources. We therefore evaluated the effect of the introduction of basic CCE over the use of DE in Victoria Hospital, a tertiary care ICU in London Ontario, Canada.

Methods: The monthly mean ratios of basic CCE and DE studies to patient care days (PCD) were plotted and general linear models were used to test for trends over time. Student t test was used to compare the mean DE/PCD before and after the introduction of basic CCE. The ratio of management actions for basic CCE studies was described. Outcome measures were compared using Pearson χ(2) test of association or the Wilcoxon rank sum test.

Results: Over the 2-year study period, 1264 basic CCE studies were performed. Over this time, the ratio of CCE/PCD increased significantly (P<.001), whereas the ratio of DE/PCD decreased significantly (P=.004). When comparing the pre- and post-CCE periods, the mean DE/PCD decreased significantly from 5.27% to 4.51% (P=.01). There was no adverse change in ICU outcomes before and after the introduction of basic CCE. Mortality rates (pre- and post-CCE) were 23.69% and 24.61% (P=.48); median length of stay was 4.18 and 3.53 days (P<.001); and ventilated patient day rate was 64.96% and 64.93% (P>.9). There was a significant increase in vasoactive/inotropic drugs from a 20.47% vasoactive/inotropic drug/patient day rate to 21.99% (P<.001). Of all basic CCE studies, 61% led to a specific management action, including ordering a DE in 10.7% of cases.

Conclusion: In a hospital with a significant increase in basic CCE use, an associated significant decrease in DE use was observed with no increase in adverse outcomes. The significant increase in basic CCE use resulted in a change of management in most cases including the request for DE in a minority of cases.

Keywords: Cardiovascular imaging; Critical care echocardiography; Diagnostic echocardiography; New technology; Resource use; Ultrasound.